Post by Terry S. Singeltary Sr. on Jul 14, 2023 9:13:58 GMT -6
TEXAS CWD Detected in Additional Breeding Facilities in Frio and Zavala Counties
Chronic Wasting Disease Detected in Additional Breeding Facilities in Frio and Zavala Counties
July 13, 2023
Media Contact: TPWD News, Business Hours, 512-389-8030 News Image Share on Facebook Share Release URL
AUSTIN — Texas Parks and Wildlife Department (TPWD) received notification of two new cases of Chronic Wasting Disease (CWD) in deer-breeding facilities in Frio and Zavala Counties.
In Frio County, a 2-year-old white-tailed doe died in a deer-breeding facility and was post-mortem tested following CWD surveillance testing requirements. This is the second deer-breeding facility in Frio County to have a positive CWD detection.
In Zavala County, a 3-year-old white-tailed buck died in a deer-breeding facility and was post-mortem tested following CWD surveillance testing requirements. This is the second deer-breeding facility in Zavala County to have a positive CWD detection.
Texas A&M Veterinary Medical Diagnostic Laboratory in College Station initially analyzed postmortem samples; the National Veterinary Services Laboratory in Ames, Iowa, provided a CWD-positive confirmation for both samples.
During the upcoming August meeting of the Texas Parks and Wildlife Commission, TPWD staff will propose the development of CWD surveillance zones within the general vicinity of both CWD-positive facilities. If the proposal passes, the zones will include mandatory sampling of hunter harvested deer, as well as carcass movement and disposal requirements to take effect during the upcoming deer season.
CWD has an incubation period that can span years, meaning the first indication in a herd may likely come through surveillance testing rather than observed clinical signs. Early detection and proactive monitoring improve the state’s response time to a disease outbreak and can greatly reduce the risk of further disease spread.
CWD is a fatal neurological disease found in certain cervids including deer, elk, moose and other members of the deer family. This slow, progressive disease may not produce visible signs in susceptible species for several years after infection. As the disease progresses, animals with CWD may show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears, and excessive thirst, salivation or urination.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border. CWD has since been detected in Texas captive and free-ranging cervids, including white-tailed deer, mule deer, red deer and elk. For more information on previous detections in Texas and CWD best management practices for hunters and landowners, visit TPWD’s CWD page.
tpwd.texas.gov/newsmedia/releases/?req=20230713a
Texas Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
For Immediate Release
April 11, 2023
Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
AUSTIN, TX – Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of two new cases of Chronic Wasting Disease (CWD) in separate deer breeding facilities in Hamilton and Frio counties. These cases mark the first detection of the disease in each county.
A single case in a Hamilton County facility was detected using antemortem (live animal) testing conducted to determine if the animal was movement qualified to transfer from the property to a registered release site. A single case in a Frio County facility was detected using postmortem testing following a natural mortality conducted to meet TPWD surveillance requirements.
The samples submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory in College Station were ultimately sent to the National Veterinary Services Laboratory (NVSL) in Ames, Iowa, where the presence of CWD was confirmed in all samples. Officials took immediate action to secure all deer at the facilities. TPWD and TAHC plan to continue working together to conduct additional investigations into the extent of the disease within the facilities.
With an incubation period that can span years, the first indication of CWD in a herd may likely come through testing, rather than observing clinical signs. Early detection and proactive monitoring improve the state’s response time to a disease outbreak and can greatly reduce the risk of further disease spread. Antemortem testing provides a continuous testing baseline that can further clarify the epidemiological uncertainties related to the origin of a disease outbreak. In addition to postmortem testing and other surveillance requirements, this testing helps guide future changes to the disease management strategy.
CWD is a fatal neurological disease found in certain cervids including deer, elk, moose and other members of the deer family. CWD is a slow and progressive disease. Due to a long incubation, cervids infected with CWD may not produce any visible signs for several years after becoming infected. As the disease progresses, animals with CWD show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, excessive thirst, salivation or urination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border. CWD has since been detected in captive and free-ranging cervids in the state including, white-tailed deer, mule deer, red deer and elk. For more information on previous detections in Texas, visit TPWD’s CWD page.
To date there are no known cases where CWD has infected a human; however, recent research suggests that CWD transmission from infected animals to humans should not be ruled out. As a precaution, it is recommended that hunters test harvested cervid species for CWD, and not consume the meat of infected animals.
For more information about CWD, visit the TPWD website or the TAHC website.
### The Texas Animal Health Commission (TAHC) was established in 1893 as the Livestock Sanitary Commission and charged with protecting the state’s domestic animals “from all contagious or infectious diseases of a malignant character.” TAHC remains true to this charge while evolving with the times to protect the health and marketability of all Texas livestock and poultry. Learn more about the TAHC visit www.tahc.texas.gov.
www.tahc.texas.gov/news/2023/2023-04-11_CWD_FrioHamilton.pdf
Texas CWD seven new cases three separate deer-breeding facilities in Zavala, Washington and Gonzales counties 471 confirmed to date
Chronic Wasting Disease Discovered in Deer-Breeding Facilities in Zavala, Washington and Gonzales Counties
March 21, 2023
Media Contact: TPWD News, Business Hours, 512-389-8030 News
Additional Case Detected at High-Fence Release Site in Hunt County
AUSTIN – The Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of seven new cases of chronic wasting disease (CWD) in three separate deer-breeding facilities in Zavala, Washington and Gonzales counties. These cases mark the first detection of the disease in each county.
Three cases in a Zavala County facility and one case in a Washington County facility were detected through antemortem (live animal) testing conducted prior to their transfer from the properties to registered release sites. Three cases in a Gonzales County facility were detected by antemortem and postmortem testing, as required by a CWD Herd Plan established after the facility received CWD-exposed deer from an Uvalde County deer breeding facility in which CWD was detected in 2021.
The samples were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory in College Station and were ultimately sent to the National Veterinary Services Laboratory in Ames, Iowa, where the presence of CWD was confirmed in all seven samples. Officials have taken immediate action to secure all deer at the facilities; TPWD and TAHC plan to continue working together to conduct additional investigations looking into the extent of the disease within the facilities.
“It continues to be imperative for producers to stay diligent with testing susceptible species for CWD,” said Dr. Andy Schwartz, TAHC executive director and state veterinarian. “With an incubation period that can span years, the first indication of this degenerative disease in a herd may likely come through testing, rather than observing clinical signs. Early detection and proactive monitoring improve the state’s response time and can greatly reduce the risk of further disease spread.”
Since November 2021, when the Texas Parks and Wildlife Commission adopted a requirement to antemortem test deer for CWD prior to liberation, this disease surveillance tool has detected CWD in five deer breeding facilities where it was not previously known to exist. Transferring even one CWD-infected deer from a breeding facility could ultimately affect all deer in the vicinity of the transfer, with irreversible impacts.
“With disease surveillance, our goal is to monitor and identify disease expeditiously to minimize the impact of outbreaks,” said Dr. Hunter Reed, TPWD wildlife veterinarian. “This is a continuous process that hopefully results in little to no disease being detected since [ideally] our disease management strategies are effective in limiting transmission. This additional surveillance from antemortem testing not only allows us to respond more quickly to an outbreak, but it also provides us with a robust, continuous testing baseline that can further elucidate the epidemiological uncertainties related to the origin of the disease outbreak, in addition to guiding future changes to our disease management strategy.”
In Hunt County, TPWD and TAHC received confirmation of CWD in a white-tailed doe harvested on a release site located adjacent to a breeding facility already known to have CWD. This is the first positive detection in a free-range deer in the county.
First recognized in the U.S. in 1967, CWD has since been documented in captive and/or free-ranging deer in 30 states and three Canadian provinces.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border and has since been detected in 471 captive or free-ranging cervids — including white-tailed deer, mule deer, red deer and elk — in 20 Texas counties. For more information on previous detections, visit TPWD’s CWD page.
CWD is a fatal neurological disease found in certain cervids, including deer, elk, moose and other members of the deer family. CWD is a slow and progressive disease. Due to a long incubation, cervids infected with CWD may not produce any visible signs for several years after becoming infected. As the disease progresses, animals with CWD show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, excessive thirst, salivation or urination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears.
To date there are no known cases where CWD has infected a human; however, recent research suggests that CWD transmission from infected animals to humans should not be ruled out. Consequently, as a precaution, it is recommended that hunters test harvested cervid species for CWD, and that no one consumes the meat of infected animals.
For more information about CWD, visit the TPWD website or the TAHC website.
tpwd.texas.gov/newsmedia/releases/?req=20230321b
“A total of 505 cervids (including white-tailed deer, mule deer and elk) have tested positive for CWD in Texas. Free-ranging deer have accounted for 101 of those cases while 404 are associated with a breeding facility or breeder release site.”
Texans spend $4.3 billion annually hunting white-tailed deer, Texas A&M study shows
TEXAS SPORTS NATION
GENERAL
Texans spend $4.3 billion annually hunting white-tailed deer, Texas A&M study shows
Matt Wyatt Staff writer May 26, 2023
Deer hunters and landowners participating in Texas' hugely popular Managed Lands Deer Program, which offers a longer deer season and other liberalized deer hunting rules, will begin paying a modest annual fee for the voluntary program under a law recently adopted by the Texas Legislature. Shannon Tompkins/Houston Chronicle
Few states, if any, can claim a closer connection to white-tailed deer hunting than Texas.
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“One of the things that there was an interest in was better understanding the overall value, or economic importance of whitetail deer within the context of various other ongoing challenges or issues, including chronic wasting disease,” Lopez said.
“There was an interest in trying to better understand the potential economic implications of a challenging issue like chronic wasting disease to this very specific industry.”
A total of 505 cervids (including white-tailed deer, mule deer and elk) have tested positive for CWD in Texas. Free-ranging deer have accounted for 101 of those cases while 404 are associated with a breeding facility or breeder release site.
There is currently no cure for CWD, and it is considered impossible to eradicate once it becomes established.
As this disease continues to creep across the Texas landscape, it could eventually have negative impacts on white-tailed deer populations.
A decline in white-tailed deer numbers could cut into the $4.3 billion spent every year on hunting, spelling disaster for the local economies and communities that depend on that money and the other wildlife species that benefit from it.
www.houstonchronicle.com/texas-sports-nation/general/article/texas-whitetail-deer-hunting-spending-18121324.php
ECONOMIC VALUES OF WHITE-TAILED DEER IN TEXAS
2022 SURVEY: PART I
nri.tamu.edu/media/3702/economic-values-of-white-tailed-deer-in-texas-2022-survey-part-i.pdf
Chronic Wasting Disease (CWD):
2021 Incident
7 Positive Facilities
3 Facilities in Uvalde, 1 in Duval, 1 in Hunt, 1 in Matagorda, & 1 in Mason
1 release site in Hunt co. associated with a positive 2021 facility - NVSL confirmed March 17, 2023.
302 Trace Herds: 177 Breeder Facilities, 116 Release Sites, 4 Nursing Facilities, 5 DMP Sites
Status
Released after meeting requirements: 165 Breeder Facilities, 59 Release Sites/DMPs /Nursing Facilities
Under a Herd Plan: 5 Breeder Facilities (includes positive facilities), 25 Release Sites/DMP
Pending a signed herd plan: 7 Breeder Facilities (includes positive facilities), 41 Release Sites/DMP
Out of State - 8 Facilities
2022 Incident - 84 total involved herds
2 Positive Facilities
Gillespie County – Confirmed August 30, 2022
Limestone County – Confirmed September 13, 2022
82 Trace Facilities
22 Breeder Facilities
59 Release Sites
1 DMP Site
Status
Released after meeting requirements: 10 Breeder Facilities, 5 Release Sites
Signed Herd Plan – 14 Release Sites
Pending Signed Herd Plan: 14 Breeder Facilities (includes positive facilities), 41 Release Sites/DMP
Summary Minutes of the 415th Commission Meeting – 4/04/2023
4
2023 Incident - 44 total affected herds
4 Positive Facilities
Zavala County – confirmed March 10, 2023
Washington County – confirmed March 7, 2023
Gonzales County – confirmed March 17, 2023
Hamilton County – confirmed March 21, 2023
40 Trace Facilities: 10 Breeder Facilities, 28 Release Sites, 1 DMP Site, 1 Nursing Facility
Status
Released after meeting requirements – 1 Breeder Facility
Under a Herd Plan- None at this time: Unconfirmed Frio County Facility- suspect positive notification received March 17, 2023
1 Positive Facility
17 Trace Facilities: 2 Breeder Facilities, 13 Release Sites, 2 DMP Sites
Released after meeting requirements – 2 Breeder Facilities
USDA VS review of the Texas CWD HCP
TAHC is working with TPWD to modify the TWIMS database to better support the HCP
Review of all enrolled herds has begun, and is to be completed by the end of February 2023
Update: USDA extended the deadline. Reviews have been completed in four of the six regions, with good progress being made in the remaining two regions.
www.tahc.texas.gov/agency/meetings/SummaryMinutesCommissionMeeting415.pdf
“Regarding the current situation involving CWD in permitted deer breeding facilities, TPWD records indicate that within the last five years, the seven CWD-positive facilities transferred a total of 2,530 deer to 270 locations in 102 counties and eight locations in Mexico (the destinations included 139 deer breeding facilities, 118 release sites, five Deer Management Permit sites, and three nursing facilities).'' ...
It is apparent that prior to the recent emergency rules, the CWD detection rules were ineffective at detecting CWD earlier in the deer breeding facilities where it was eventually discovered and had been present for some time; this creates additional concern regarding adequate mitigation of the risk of transferring CWD-positive breeder deer to release sites where released breeder deer come into contact with free-ranging deer...
Commission Agenda Item No. 5 Exhibit B
DISEASE DETECTION AND RESPONSE RULES
PROPOSAL PREAMBLE
1. Introduction.
snip...
A third issue is the accuracy of mortality reporting. Department records indicate that for each of the last five years an average of 26 deer breeders have reported a shared total of 159 escapes. Department records for the same time period indicate an average of 31 breeding facilities reported a shared total of 825 missing deer (deer that department records indicate should be present in the facility, but cannot be located or verified).
tpwd.texas.gov/business/feedback/meetings/2022/1104/agenda/item.phtml?item=5
Commission
September 22, 2020
Chronic Wasting Disease (CWD):
A new CWD positive breeding herd was disclosed in February 2020 in Kimble County. This herd depopulation was completed in July 2020. Including the two index positive deer, an additional eight more positive deer were disclosed (approximate herd prevalence 12%). Since July 2015 and prior to this discovery, five positive captive breeder herds have been disclosed and four of those are in Medina County. One herd in Lavaca and three herds in Medina County were depopulated leaving one large herd in Medina County that is managed on a herd plan. A new zone was established in Val Verde County in December 2019 as a result of a positive free-ranging White-tailed Deer (WTD). A second positive WTD was also disclosed in February 2020 in the same area.
SUMMARY MINUTES OF THE 407th COMMISSION MEETING – 9/22/2020
Scrapie: The flock identified in April 2016 remains under quarantine in Hartley County.
SUMMARY MINUTES OF THE 407th COMMISSION MEETING – 9/22/2020
Texas CWD Herd Kimble County Has approximate prevalence 12% to date
web.archive.org/web/20201020110225/https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22.pdf
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas. Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
CWD poses a significant threat to the future of hunting in Texas. Deer population declines of 45 and 50 percent have been documented in Colorado and Wyoming. A broad infection of Texas deer populations resulting in similar population impacts would inflict severe economic damage to rural communities and could negatively impact land markets. Specifically, those landowners seeking to establish a thriving herd of deer could avoid buying in areas with confirmed CWD infections. As they do with anthrax-susceptible properties, land brokers may find it advisable to inquire about the status of CWD infections on properties that they present for sale. Prospective buyers should also investigate the status of the wildlife on prospective properties. In addition, existing landowners should monitor developments as TPWD crafts management strategies to identify and contain this deadly disease.
Dr. Gilliland (c-gilliland@tamu.edu) is a research economist with the Texas Real Estate Research Center at Texas A&M University.
www.recenter.tamu.edu/articles/tierra-grande/oh-deer-2314
Texas CWD Surveillance Positives
tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD
Counties where CWD Exposed Deer were Released
tpwd.texas.gov/documents/257/CWD-Trace-OutReleaseSites.pdf
Number of CWD Exposed Deer Released by County
tpwd.texas.gov/documents/258/CWD-Trace-OutReleaseSites-NbrDeer.pdf
Chronic Wasting Disease CWD Captive Herds updated April 2023
www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/cervid/cervids-cwd/cervids-voluntary-hcp
Chronic Wasting Disease CWD Captive Herds updated April 2023
www.aphis.usda.gov/animal_health/animal_diseases/cwd/downloads/status-of-captive-herds.pdf
Listing of CWD Cases in Texas
tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD
“Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.”
PART 2. TPWD CHAPTER 65. DIVISION 1. CWD
31 TAC §§65.82, 65.85, 65.88
The Texas Parks and Wildlife Commission in a duly noticed meeting on May 25, 2023 adopted amendments to 31 TAC §§65.82, 65.85, and §65.88, concerning Disease Detection and Response, without changes to the proposed text as published in the April 21, 2023, issue of the Texas Register (48 TexReg 2048). The rules will not be republished.
Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.
www.sos.texas.gov/texreg/archive/June302023/Adopted%20Rules/31.NATURAL%20RESOURCES%20AND%20CONSERVATION.html#57
TEXAS CWD STRAIN
“Wow,” he said. “Unlike anything we've seen before.”
The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.
TEXAS CWD STRAIN
77. Assessing chronic wasting disease strain differences in free-ranging cervids across the United States
Kaitlyn M. Wagnera, Caitlin Ott-Connb, Kelly Strakab, Bob Dittmarc, Jasmine Battend, Robyn Piercea, Mercedes Hennessya, Elizabeth Gordona, Brett Israela, Jenn Ballarde and Mark D Zabela
aPrion Research Center at Colorado State University; bMichigan Department of Natural Resources; cTexas Parks and Wildlife Department; dMissouri Department of Conservation, 5. Arkansas Game and Fish Commission CONTACT Kaitlyn M. Wagner miedkait@rams.colostate.edu
ABSTRACT
Background/Introduction: Chronic wasting disease (CWD) is an invariably fatal prion disease affecting captive and free-ranging cervids, including white-tailed deer, mule deer, moose, elk, and reindeer. Since the initial description of the disease in the 1960’s, CWD has spread to 23 states, 3 Canadian Provinces, South Korea, Norway and, most recently, Finland. While some outbreaks of CWD were caused by transport of infected animals from endemic regions, the origin of CWD in other epizootics is unclear and has not been characterized. Previous studies have shown that there are two distinct strains of CWD. However, the continuous spread and the unclear origin of several outbreaks warrant continued surveillance and further characterization of strain diversity.
Materials and Methods: To address these knowledge gaps, we used biochemical tests to assess strain differences between CWD outbreaks in Michigan, Texas, Missouri, and Colorado, USA. Brain or lymph node samples were homogenized and digested in 50 µg/mL proteinase K (PK). These samples were then run on a Western blot to assess glycoform ratio and electrophoretic mobility. Texas samples were digested in 100 µg/mL PK. To assess conformational stability, brain or lymph node homogenates were incubated in increasing concentrations of guanidine hydrochloride from 0 M to 4 M in 0.5 M increments. Samples were then precipitated in methanol overnight, washed and PK digested in 50 µg/mL PK before slot blotting.
Results: Our results have found significant differences in glycoform ratio between CWD from Michigan and Colorado, but no differences were observed in conformational stability assays. Interestingly, when testing our CWD isolates from Texas to analyse electrophoretic mobility and glycoform ratio, we found that these samples did not exhibit the characteristic band shift when treated with PK, but PK resistant material remained. Additionally, results from our conformational stability assay demonstrate a unique profile of these Texas isolates. Testing of samples from Missouri is currently underway.
Conclusions: Thus far, our data indicate that there are strain differences between CWD circulating in Michigan and CWD in Colorado and provide important insight into CWD strain differences between two non-contiguous outbreaks. We have also identified a unique strain of CWD in Texas with biochemical strain properties not seen in any of our other CWD isolates. These results highlight the importance of continued surveillance to better understand this devastating disease. These results have important implications for CWD emergence, evolution and our understanding of prion strain heterogeneity on the landscape.
www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
CWD TEXAS SUTTON COUNTY FACILITY
www.tahc.texas.gov/news/2023/2023-05-08_CWD_Sutton.pdf
"Initial investigations indicate 10 additional breeding facilities and 18 release sites may have been impacted from previous transfers received from deer that originated in the Sutton County facility."
TEXAS REPUBLICAN SB 1372 TAXPAYERS TO PAY FOR GAME FARMS CWD DEPOPULATION?
SB 1372
A BILL TO BE ENTITLED
AN ACT relating to costs associated with the destruction of certain deer.
BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF TEXAS:
SECTION 1. Section 43.955, Parks and Wildlife Code, is amended to read as follows:
Sec. 43.955. COST OF ASSESSMENT AND DESTRUCTION OF DEER [RECOVERY]. (a) The applicable permit holder shall pay all costs associated with:
(1) an epidemiological assessment conducted under this subchapter to the animal health commission; and
(2) except as provided by Subsection (b), the destruction of deer under this subchapter to the department.
(b) Except as provided by Subsection (c), the department shall waive the costs associated with the destruction under this subchapter of breeder deer at a facility covered by a permit issued under Subchapter L where a breeder deer has tested positive for chronic wasting disease in a test performed by a testing laboratory accredited by the Animal and Plant Health Inspection Service of the United States Department of Agriculture.
(c) The department may not waive costs under Subsection (b) if the department determines that the permit holder or an agent of the permit holder, in violation of this chapter or a regulation of the commission, caused:
(1) the introduction of chronic wasting disease into the facility; or
(2) a delay in the detection of chronic wasting disease at the facility.
SECTION 2. Section 43.955, Parks and Wildlife Code, as amended by this Act, applies only to the payment of costs arising from the destruction of deer commenced on or after the effective date of this Act.
SECTION 3. This Act takes effect immediately if it receives a vote of two-thirds of all the members elected to each house, as provided by Section 39, Article III, Texas Constitution. If this Act does not receive the vote necessary for immediate effect, this Act takes effect September 1, 2023.
legiscan.com/TX/text/SB1372/2023
That can mean the killing of hundreds of expensive animals, and the financial ruin of their rancher.
snip...
“This bill essentially allows Parks and Wildlife to absorb that cost, which we believe helps remove the threat from the landscape quicker, with better landowner relations for the department, and ultimately we think that moves the needle as far as managing the disease,” Dreibelbis said.
snip...
In order to become law, the CWD bill still has to pass the House chamber with a majority vote and then be signed by Gov. Greg Abbott. The chair of the House committee that most recently approved the bill, Rep. Trent Ashby, said in an emailed statement that he was pleased to see the bill making its way through the legislature.
TEXAS REPUBLICAN SB 1372 TAXPAYERS TO PAY FOR CWD TSE PRION DEPOPULATION OF GAME FARMS
The chair of the House committee that most recently approved the bill, Rep. Trent Ashby, said in an emailed statement that he was pleased to see the bill making its way through the legislature.
www.star-telegram.com/news/state/texas/article274737181.html
SO, the taxpayers will have the burden of paying for deer breeders cost of depopulation of their CWD deer herd?...that's crazy if true, and everyone should write Governor Abbott and tell him...taxpayers should not have to pay for game farms cwd depopulation...IMO...terry
what's Governor Abbott history with supporting deer farms?
Governor Abbott on HOW TO LEGISLATE SPREADING CWD TO HELL AND BACK IN TEXAS $$$
i picked up on something that was said, there were several folks complaining that the breeders were getting picked on, and someone said something about trying to 'legislate' there way out of this. folks, this is terrible, i have seen this in other states, and it just spreads cwd even more. hell, it happened right here in Texas in the early days, that's why we are where were at now, you cannot let a bunch of Austin Legislative Socialites regulate CWD, just look what happened in Wisconsin. but i bet this attempted swaying of regulatory power shift from TPWD et al to the Texas Legislature in Austin is happening as we speak. we can't let this happen...
SUNDAY, JANUARY 22, 2017
Texas 85th Legislative Session 2017 Chronic Wasting Disease CWD TSE Prion Cervid Captive Breeder Industry
FRIDAY, JANUARY 27, 2017
TEXAS, Politicians, TAHC, TPWD, and the spread of CWD TSE Prion in Texas
SUNDAY, MAY 14, 2017
85th Legislative Session 2017 AND THE TEXAS TWO STEP Chronic Wasting Disease CWD TSE Prion, and paying to play $$$
Powerful Abbott appointee's lobbying sparks blowback in Legislature
In an ironic twist for Gov. Greg Abbott, who has made ethics reform an urgent political priority, the Texas House is taking aim at what critics call a "pay to play" culture among his appointees.
BY JAY ROOT MAY 12, 2017 12 AM
Houston billionaire Dan Friedkin is chairman of the Texas Parks and Wildlife Commission.
Texas Parks and Wildlife Commission
When Gov. Greg Abbott tapped one of his top campaign donors to become chairman of the Texas Parks and Wildlife Commission, he didn’t get a part-time appointee who would merely draft rules and implement conservation laws passed by the Legislature.
In Dan Friedkin, the governor got a Houston billionaire — with a team of privately funded lobbyists — willing to use his influence to ensure his wildlife interests are taken into account by the Legislature before they pass those laws, interviews and records show.
On the receiving end of that influence, and not in a happy way, is state Rep. Chris Paddie, R-Marshall. Paddie said a lobbyist working for Friedkin’s business empire, which includes a massive South Texas hunting ranch, has been working against his deer breeder management bill, which many large ranchers oppose. The state Parks and Wildlife Department oversees deer breeding regulations in Texas.
“Many times these appointees are well-heeled, very influential people,” Paddie said. “Overall, I feel that it’s inappropriate for an appointee of a board or commission to have personal lobbyists lobbying on issues related to that board or commission.”
Under Texas law, state agencies are barred from lobbying the Legislature. But the powerful people who oversee them aren’t.
If Paddie and dozens of his colleagues get their way, that practice soon will be a Class A misdemeanor.
Last weekend, Paddie attached a ban on appointee lobbying — which would apply to any issues intersecting with their state responsibilities — to an ethics bill that already had powerful friends of the governor in its crosshairs. The provision was adopted unanimously and the bill sailed out of the Texas House on a 91-48 vote Saturday.
The ethics bill, authored by Rep. Lyle Larson, R-San Antonio, would bar big campaign donors from getting appointed by governors in the first place. Anyone who contributed over $2,500 would be barred from serving on state boards and commissions.
Larson pointed to news articles documenting the amount of campaign money appointees have collectively given governors. Last year the San Antonio Express-News calculated that Abbott had received nearly $9 million from people he’s picked for appointed office; before that, a widely cited report from Texans for Public Justice found former Gov. Rick Perry had received $17 million from his own appointees.
Larson said 20 years from now, Texans will be reading the same stories about a future governor unless the Legislature does something about it now.
“We’ve read that article for the last three decades,” Larson said during a brief floor speech. “This is your opportunity to say, 'We need to stop this.' The most egregious ethics violation we’ve got in the state is the pay to play in the governor’s office.”
A prodigious fundraiser, Abbott has put plenty of big donors on prestigious boards and commissions. On the Parks and Wildlife Commission alone, he has installed three mega-donors — pipeline mogul Kelcy Warren, who’s given Abbott more than $800,000 over his statewide political career; Houston businessman S. Reed Morian, who has given $600,000; and Friedkin, who personally donated more than $700,000 — while his Gulf States Toyota PAC gave Abbott another $100,000, according to Ethics Commission records.
Passage of Larson’s HB 3305 represents an ironic twist for Abbott, who for the second session in a row has made ethics reform an urgent political priority — resulting in a bill that's now taking aim at his gubernatorial appointments. Abbott, who has made a habit of ignoring tough questions, hasn't made any public statements about the bill, and his office did not respond to multiple requests for comment.
Friedkin — whose wealth is estimated at $3.4 billion by Forbes — is the owner and CEO of Gulf States Toyota, founded in 1969, which has had the exclusive rights to distribute new Toyotas in Texas and four nearby states. He’d also been a mega-donor to former Gov. Rick Perry, who first appointed Friedkin to the Parks and Wildlife Commission in 2005. Abbott made Friedkin chairman of the commission in 2015.
Requests for comment from Friedkin's office went unanswered.
In addition to his public role as parks and wildlife chairman, a perch that gives him significant influence over deer management issues, Friedkin has private wildlife interests. He owns the sprawling Comanche Ranch in South Texas, according to published news accounts.
The January 2014 edition of Texas Wildlife, published by the Texas Wildlife Association, described Friedkin’s Comanche Ranch as “privately owned and privately hunted” and said it’s “in the business to produce as many trophy bucks as possible, without damaging the native habitat.”
The association, which advocates for private landowners and hunting rights, has locked horns with deer breeding interests at Parks and Wildlife and the Capitol. They compete against each other in the lucrative trophy deer hunting market — and the battle between them perennially spills into the rule-making process at the Parks and Wildlife Commission.
One of their battles centers on how captive deer are tagged so that game wardens and others can distinguish them from native deer. Current law requires a combination of tags and tattoos, and the ranchers and large landowners want to keep it that way. The breeders, meanwhile, favor tagging deer with microchips, which they contend are more accurate and foolproof.
The Wildlife Association said in a Facebook post that removing visible tag or tattoo requirements and allowing microchip tracking “creates real biosecurity risks and blurs ethical lines in the hunting community, as captive deer breeders are allowed to transport and release these animals to be co-mingled with pasture-born deer.” Proponents of the current system say tough rules on breeders are needed to keep out imported deer that may carry Chronic Wasting Disease, which has been found in Texas.
On the other side of the issue is the Texas Deer Association, which represents breeder interests. Executive Director Patrick Tarlton said opposition to his $1.6 billion industry stems less from environmental and health concerns and more from wealthy ranch owners who want to boost profits from trophy-seeking hunters. He notes that Chronic Wasting Disease has been found in both free range and captive deer.
Paddie sided with the breeders by filing House Bill 2855, which would allow breeders to track their deer with microchips instead of relying on physical tags that they say can be torn off.
No one identifying themselves as a Friedkin corporate lobbyist opposed the deer breeding bills during public hearings, according to House and Senate committee records published online.
Behind the scenes, it was a different story.
Paddie said his chief of staff reached out to Laird Doran, one of several lobbyists for Friedkin’s Gulf States Toyota, after hearing that he was trying to convince other legislators to help defeat Paddie's deer microchip bill.
“My chief called him and said, 'Hey, if you’ve got a problem with our bill why aren’t you talking to us?’ ” Paddie said. “He said he represented the Friedkin Group when that happened.”
According to an email from an aide to Sen. Craig Estes, R-Wichita Falls, who is carrying the deer breeding bill in the Senate, Doran also identified himself as a representative of the “Friedkin Group.” That’s the name of the consortium that contains Friedkin's Gulf States Toyota, according to the company’s Linked-In page. He told Estes’ aide that the Friedkin group was opposed to any bill that would “remove requirements for (deer) ear tags,” the senator’s office confirmed.
It’s not clear exactly which Friedkin interests Doran was advancing. Doran is registered at the Texas Ethics Commission with a single entity — Gulf States Toyota — and the agency has no record of a lobbyist working for an entity or individual with the name Friedkin in it, the commission confirmed Wednesday afternoon.
However, Doran checked a variety of non-automotive subject areas in which he is lobbying during this legislative session on behalf of Friedkin’s lucrative distributorship, including “animals,” “parks & wildlife,” “state agencies, boards & commissions,” “environment” and more, his detailed lobby disclosures show.
Doran, director of government relations and senior counsel at the Friedkin Group, did not return phone and email messages left by The Texas Tribune.
Estes said he didn’t have a problem with a governor's appointee engaging in lobbying on issues that affected their private interests, as long as they keep that separate from their state roles.
“I don’t think they should be barred from expressing their views as long as they’re careful to say these are my views, not the views of the agency I’m representing,” Estes said.
But Tarlton, the deer association director, said Friedkin’s use of lobbyists to oppose deer breeders in the Legislature gives the breeders' opponents a huge advantage.
“I think that if the commissioner of Texas Parks and Wildlife is actively lobbying against an industry which his department directly oversees, it absolutely sets up an unfair and closed system of government,” Tarlton said. “The commission is supposed to be the unbiased and equitable oversight for everything wildlife.”
Paddie hopes his amendment to Larsen's ethics bill will even the playing field. He referred to the wealthy Parks and Wildlife chairman (see the 2:29:00 mark in this recorded exchange) when he tacked the appointee-lobbying provision onto Larson’s bill.
Paddie said he’s not singling out anyone. He said it would apply to other powerful gubernatorial appointees in a position to do the same.
“I could have named any number of examples as far as the agencies in particular,” Paddie said. “I want to stop it if anyone serving on any agency is doing this.”
Ryan Murphy contributed to this report.
Disclosure: The Texas Wildlife Association, Texas Parks and Wildlife Department and Gulf States Toyota have been financial supporters of The Texas Tribune. A complete list of Tribune donors and sponsors is available here.
www.texastribune.org/2017/05/12/powerful-abbott-appointees-lobbying-sparks-blowback-legislature/
MONDAY, MAY 15, 2023
TAHC Chapter 40, Chronic Wasting Disease and Scrapie Chapter 60, Singeltary Comment Submission
Greetings TAHC et al,
Thank you kindly for giving me the opportunity to once again comment on CWD and Scrapie.
I want to thank the TAHC and the TPWD for coming together and seems now bring forth sound science, of the real risk factors for both CWD and Scrapie.
With great urgency, i wish to bring your attention on updated Science on Chronic Wasting Disease CWD and Scrapie TSE Prion Environmental Factors and Zoonotic factors, spillover risk factors of CWD and Scrapie to other species i.e. PIGS, our failed feed ban of which now should include all cervid and pigs imo. i saw no mention of atypical Scrapie and the new science from EFSA, i shall include that as well. there is a new TSE Prion disease in a new livestock species the Camel, you should all be aware of. all of this is most important, and should be addressed in any cwd update imo, especially with CWD and Scrapie transmitting to pigs by oral routes.
i will post my concerns below, Thank You Kindly...terry
TAHC Chapter 40, Chronic Wasting Disease and Scrapie Chapter 60, Singeltary Comment Submission
transmissiblespongiformencephalopathy.blogspot.com/2023/05/tahc-chapter-40-chronic-wasting-disease.html
WEDNESDAY, JUNE 14, 2023
Texas TPWD CWD 508 Cases Confirmed To Date
chronic-wasting-disease.blogspot.com/2023/06/texas-tpwd-cwd-508-cases-confirmed-to.html
TUESDAY, MAY 30, 2023
Texas Chronic Wasting Disease Detected in a Free-Range Deer in Bexar County 506 Cases and Mounting
chronic-wasting-disease.blogspot.com/2023/05/texas-chronic-wasting-disease-detected.html
SATURDAY, MAY 27, 2023
TEXAS CWD NOW CONFIRMED 505 Cervid, 101 Wild and 404 associated with breeding facility or breeder release site
chronic-wasting-disease.blogspot.com/2023/05/texas-cwd-now-confirmed-505-cervid-101.html
MONDAY, MAY 08, 2023
TEXAS Chronic Wasting Disease Discovered in Deer Breeding Facility in Sutton County
chronic-wasting-disease.blogspot.com/2023/05/texas-chronic-wasting-disease.html
TUESDAY, APRIL 11, 2023
Texas TAHC Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
chronic-wasting-disease.blogspot.com/2023/04/texas-tahc-chronic-wasting-disease.html
TUESDAY, MARCH 21, 2023
Texas CWD seven new cases three separate deer-breeding facilities in Zavala, Washington and Gonzales counties 471 confirmed to date
chronic-wasting-disease.blogspot.com/2023/03/texas-cwd-seven-new-cases-three.html
FRIDAY, FEBRUARY 17, 2023
TEXAS OVERVIEW OF STATE RESPONSE TO CHRONIC WASTING DISEASE CWD TSE PRION April 2019 a Review
chronic-wasting-disease.blogspot.com/2023/02/texas-overview-of-state-response-to.html
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
Greetings APHIS et al, i would kindly like to comment on Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004.
Greetings APHIS et al, i would kindly like to comment on Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004.
***> 1st and foremost your biggest problem is 'VOLUNTARY'! AS with the BSE 589.2001 FEED REGULATIONS, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.
***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.
***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently.
***> 4th Captive Farmed Cervid, INDEMNITY, NO MORE Federal indemnity program, or what i call, ENTITLEMENT PROGRAM for game farm industry. NO MORE BAIL OUTS FROM TAX PAYERS. if the captive industry can't buy insurance to protect not only themselves, but also their customers, and especially the STATE, from Chronic Wasting Disease CWD TSE Prion or what some call mad deer disease and harm therefrom, IF they can't afford to buy that insurance that will cover all of it, then they DO NOT GET A PERMIT to have a game farm for anything. This CWD TSE Prion can/could/has caused property values to fall from some reports in some places. roll the dice, how much is a state willing to lose?
***> 5th QUARANTINE OF ALL FARMED CAPTIVE, BREEDERS, URINE, ANTLER, VELVET, SPERM, OR ANY FACILITY, AND THEIR PRODUCTS, that has been confirmed to have Chronic Wasting Disease CWD TSE Prion, the QUARANTINE should be for 21 years due to science showing what scrapie can do. 5 years is NOT near long enough. see; Infectious agent of sheep scrapie may persist in the environment for at least 16 to 21 years.
***> 6th America BSE 589.2001 FEED REGULATIONS CWD TSE Prion
***> 7TH TRUCKING TRANSPORTING CERVID CHRONIC WASTING DISEASE TSE PRION VIOLATING THE LACEY ACT
***> 8TH ALL CAPTIVE FARMING CERVID OPERATIONS MUST BE INSURED TO PAY FOR ANY CLEAN UP OF CWD AND QUARANTINE THERE FROM FOR THE STATE, NO MORE ENTITLEMENT PROGRAM FOR CERVID GAME FARMING PAY TO PLAY FOR CWD TSE PRION OFF THE TAX PAYERS BACK.
***> 9TH ANY STATE WITH DOCUMENTED CWD, INTERSTATE, NATIONAL, AND INTERNATIONAL MOVEMENT OF ALL CERVID, AND ALL CERVID PRODUCTS MUST BE HALTED!
***> 10TH BAN THE SALE OF STRAW BRED BUCKS AND ALL CERVID SEMEN AND URINE PRODUCTS
***> 11th ALL CAPTIVE FARMED CERVID AND THEIR PRODUCTS MUST BE CWD TSE PRION TESTED ANNUALLY AND BEFORE SALE FOR CWD TSE PRION
SEE FULL SCIENCE REFERENCES AND REASONINGS ;
***> 1st and foremost your biggest problem is 'VOLUNTARY'!
''APHIS created a cooperative, voluntary Federal-State-private sector CWD Herd Certification Program designed to identify farmed or captive herds infected with CWD.''
key word failure is 'voluntary'.
WE know for a fact now that voluntary does NOT WORK!
AS with the BSE 589.2001 FEED REGULATIONS (see , another colossal failure, and proven to be a sham, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.
***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.
***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently. ...snip...see full text submission with science references...TSS
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
www.regulations.gov/comment/APHIS-2021-0004-0002
downloads.regulations.gov/APHIS-2021-0004-0002/attachment_1.pdf
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification
www.regulations.gov/document/APHIS-2018-0011-0003
downloads.regulations.gov/APHIS-2018-0011-0003/attachment_1.pdf
The disease devastating deer herds may also threaten human health
Scientists are exploring the origins of chronic wasting disease before it becomes truly catastrophic.
Rae Ellen Bichell
Image credit: David Parsons/Istock
April 8, 2019
This story was published in collaboration with the Mountain West News Bureau, a collaboration between Wyoming Public Media, Boise State Public Radio in Idaho, KUER in Salt Lake City and KRCC and KUNC in Colorado.
SNIP...
One day in late February, in their laboratory in Fort Collins, Colorado, Wagner and Zabel compared the prions from the brains of CWD-infected deer in Texas with those of elk in Colorado. They want to know if the proteins were all mangled in the same way, or not. “If they are different, this would suggest that we have different strain properties, which is evidence as we're building our case that we might have multiple strains of CWD circulating in the U.S.,” says Wagner.
Step one is to see if they’re equally easy to destroy using a chemical called guanidine. The shape of a prion dictates everything, including the way it interacts with an animal’s cells and the ease with which chemicals can unfold it.
“Moment of truth,” said Wagner, as she and Zabel huddled around a computer, waiting for results to come through. When they did, Zabel was surprised.
“Wow,” he said. “Unlike anything we've seen before.”
The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.
Now, these are only the preliminary results from a few animals. Wagner and Zabel have a lot more experiments to do. But if future tests come to the same conclusion, it would support their hypothesis that there are multiple strains of chronic wasting disease out there, all with different origins. That, in turn, could mean that this disease will become even trickier to manage than it already is.
And, Zabel adds, there’s something else. “If it's still evolving, it may still evolve into a form that could potentially, eventually affect humans,” he says.
Zabel is not the only one worried about that possibility.
OSTERHOLM, THE EPIDEMIOLOGIST from Minnesota, is also concerned. He directs the Center for Infectious Disease Research and Policy at the University of Minnesota, and is serving a one-year stint as a “Science Envoy for Health Security” with the U.S. State Department. In February, he told Minnesota lawmakers that when it comes to chronic wasting disease, we are playing with fire. “You are going to hear from people that this is not going to be a problem other than a game farm issue. You're going to hear from people that it's not going to transmit to people, and I hope they're right, but I wouldn't bet on it,” he said. “And if we lose this one and haven’t done all we can do, we will pay a price.”
If that wasn’t warning enough, he added: “Just remember what happened in England.”
He was talking about mad cow disease. Decades ago, Osterholm got involved in studying the potential for the newly emerging condition — bovine spongiform encephalopathy, or BSE for short — to be transmitted to humans.
At that point, researchers had yet to document a prion disease in animals that could infect people. They did, however, have a few pieces of the puzzle. For one, work in Papua New Guinea had shown that people could transmit prion diseases to each other if they practiced cannibalism, especially of the brain-eating variety. They also knew that BSE was spreading quickly between cattle. Osterholm says he and others worried that the more widespread it became, the more chances it might have to change into something that could sicken people.
“A lot of people thought that it was an overreaction,” says Osterholm. “Then, of course, in 1996, 10 years later, we recognized that in fact transmission had occurred.” Variant Creutzfeldt-Jakob disease, as the illness is called when it appears in human beings, has infected about 230 people worldwide. Osterholm says he feels like he’s having déjà vu, except that instead of mad cow, now it’s chronic wasting disease that’s spreading in animals, with the potential to cross the species barrier to infect humans.
SNIP...SEE FULL TEXT;
www.hcn.org/articles/wildlife-the-disease-devastating-deer-herds-may-also-threaten-human-health-science
***> TEXAS BREEDER DEER ESCAPEE WITH CWD IN THE WILD, or so the genetics would show?
OH NO, please tell me i heard this wrong, a potential Texas captive escapee with cwd in the wild, in an area with positive captive cwd herd?
apparently, no ID though. tell me it ain't so please...
23:00 minute mark
''Free Ranging Deer, Dr. Deyoung looked at Genetics of this free ranging deer and what he found was, that the genetics on this deer were more similar to captive deer, than the free ranging population, but he did not see a significant connection to any one captive facility that he analyzed, so we believe, Ahhhhhh, this animal had some captive ahhh, whatnot.''
youtu.be/aoPDeGL6mpQ?t=1384
Biologists Stress Testing Harvests for Chronic Wasting Disease During Deer Season
Dec. 2, 2022
Media Contact: TPWD News, Business Hours, 512-389-8030
tpwd.texas.gov/newsmedia/releases/?req=20221202b
April 22, 2016
Scrapie Confirmed in a Hartley County Sheep
AUSTIN - Texas Animal Health Commission (TAHC) officials have confirmed scrapie in a Hartley County ewe. The ewe was tested by TAHC after the owner reported signs of weight loss and lack of coordination to their local veterinarian. The premises was quarantined and a flock plan for monitoring is being developed by the TAHC and USDA.
"The TAHC is working closely with the flock owner, sharing all of the options for disease eradication," said Dr. David Finch, TAHC Region 1 Director. "We are thankful the producer was proactive in identifying a problem and seeking veterinary help immediately."
Texas leads the nation in sheep and goat production. Since 2008, there have been no confirmed cases of scrapie in Texas. The last big spike in Texas scrapie cases was in 2006 when nine infected herds were identified and the last herd was released from restrictions in 2013.
According to USDA regulations, Texas must conduct adequate scrapie surveillance by collecting a minimum of 598 sheep samples annually. Since USDA slaughter surveillance started in FY 2003, the percent of cull sheep found positive for scrapieat slaughter (once adjusted for face color) has decreased 90 percent.
Scrapie is the oldest known transmissible spongiform encephalopathies, and under natural conditions only sheep and goats are known to be affected by scrapie. It is a fatal disease that affects the central nervous system of sheep and goats. It is not completely understood how scrapie is passed from one animal to the next and apparently healthy sheep infected with scrapie can spread the disease. Sheep and goats are typically infected as young lambs or kids, though adult sheep and goats can become infected.
The most effective method of scrapie prevention is to maintain a closed flock. Raising replacement ewes, purchasing genetically resistant rams and ewes,or buying from a certified-free scrapie flock are other options to reduce the risk of scrapie. At this time the resistant genetic markers in goats have not been identified, therefore it is important to maintain your sheep and goat herds separately.
The incubation period for Scrapie is typically two to five years. Producers should record individual identification numbers and the seller's premise identification number on purchase and sales records. These records must be maintained for a minimum of five years.
Producers should notify the Texas Animal Health Commission (800-550-8242) or the USDA-Austin Office (512-383-2400) if they have an adult sheep or goat with neurologic signs such as incoordination, behavioral changes, or intense itching with wool loss. Producers may order scrapie identification tags by calling 866-873-2824. For more information, please visit our website at:
www.tahc.texas.gov/animal_health/scrapie/scrapie.htm
web.archive.org/web/20160607024701/http://www.tahc.texas.gov/news/pr/2016/2016-04-22_TAHCScrapie.pdf
Scrapie: The flock identified in April 2016 remains under quarantine in Hartley County.
www.tahc.texas.gov/agency/meetings/minutes/Minutes_CommMtg_2020-09-22.pdf
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie TSE Prion Experiment 1964 How Did CWD Get Way Down In Medina County, Texas?
DISCUSSION
Observations of natural outbreaks of scrapie indicated that the disease spread from flock to flock by the movement of infected, but apparently normal, sheep which were incubating the disease.
There was no evidence that the disease spread to adjacent flocks in the absent of such movements or that vectors or other host species were involved in the spread of scrapie to sheep or goats; however, these possibilities should be kept open...
snip...PLEASE READ THE FULL REPORT ON THE SCRAPIE FIELD TRIAL EXPERIMENTS IN MISSION, TEXAS!!!
web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
4 MOST ENDANGERED WHITETAIL DESTINATIONS IN AMERICA
Mark Kenyon
MARK KENYON Jun 3, 2022
4 Most Endangered Whitetail Destinations in America
It would not be hyperbole to say that we’re quite possibly living in the “golden age” of whitetail deer hunting.
Deer populations might be higher now than ever before and, at least since records have been kept, bigger, older bucks have never been more numerous. Hunters smash world and state records every year. The good times sure seem to be rolling.
But this isn’t true across all aspects or locales within the whitetail range, nor is it guaranteed to remain true into the future. All good things can and do come to an end.
The future of deer and deer hunting, as is the case with almost every aspect of the natural world today, exists on a precipice. Serious threats like disease, habitat loss, resource management, and public opinion all loom on the horizon. Four specific threatened locations, in particular, stand out as representative of larger issues threatening our nation’s deer hunting future. These are, in our estimation, the four most endangered whitetail destinations in America.
Read on for an introduction to these special yet threatened whitetail locales. And find out what we can do as deer hunters and stewards of the land to address the challenges in these specific locations and across the nation.
SOUTHWESTERN WISCONSIN
Greatest Threat: Chronic Wasting Disease
Southwest Wisconsin, a world-renowned big buck destination, is also ground zero for chronic wasting disease. The 100% fatal neurological disease impacting whitetails and other deer species has now spread to 29 states across the country. CWD is widely recognized as possibly the greatest existential threat to the future of whitetail hunting, and no place is it more ubiquitous than Wisconsin’s driftless area.
In some regions here, hunters are observing population-level impacts and CWD prevalence rates have hit as high as 30%. In more practical terms, this means that some areas of the whitetail-crazy state of Wisconsin might be experiencing the beginnings of downward trends in populations due to CWD. Almost one in three deer tested in these areas are testing positive. While CWD’s large-scale impact on deer populations is no joke, an equally concerning risk is the impact that positive tests have on the desire to hunt and eat deer at all. While transmission from deer to humans hasn’t been documented, it’s theoretically possible—akin to what happened with Mad Cow Disease in the 1990s. For this reason, the CDC currently advises hunters not to consume venison from a CWD-positive deer. The result of all this is that a lot of hard-earned venison is getting thrown in the dump already, and things, hypothetically, stand to worsen.
This worst-in-class state of affairs is partly due to a passive approach to CWD management that Wisconsin adopted in 2012, moving away from their “earn a buck” rule, stopping targeted population controls, and making testing in known CWD areas only voluntary.
“Because of the passive management approach taken by Wisconsin, CWD is endemic to five southwest counties, has spread to surrounding counties, and has been found in 38 of the state’s 72 counties,” said southwestern Wisconsin resident, hunter, and land consultant Doug Duren. “In some areas in those counties where prevalence is being studied, over 50% of adult bucks and over 35% of adult does are CWD positive.”
In conversations with other area residents, Duren heard anecdotal reports of seeing fewer older deer and mature bucks, increasing numbers of late-stage infected animals in need of putting down, and already dead deer. “One member of a group of hunters with a lease in Iowa County, Wisconsin told me they decided to give up their lease and find opportunity elsewhere as every buck they killed in the past three years tested positive for CWD,” he said. “This is a cautionary tale.”
While there is no single simple fix to this problem, the recently introduced Chronic Wasting Disease Research and Management Act would designate $35 million in badly needed funding for CWD research and another $35 million for management and surveillance that would certainly help the situation in Wisconsin and beyond. Click here to let your senators know this is an issue of supreme importance to deer hunters in your state.
SNIP...
TEXAS
Greatest Threat: Captive Deer Industry
The great state of Texas sports one of the most robust and proud deer hunting cultures in the nation, but it’s also home to what some consider the greatest threat to deer hunting in all of America: the captive deer industry.
The debate around the captive deer industry is complicated, long-standing, and fraught, but the issues can be distilled into two main categories. First is the well-documented risk of spreading CWD by way of the transfer and sale of captive deer. Second is the negative impact that captive deer shooting facilities, and the media created around them, can have on the public perception of hunting in America and the North American Model of Conservation.
Texas is home to more captive deer facilities than any other state by a long shot, with 858 locations. The conditions present at such facilities, with high numbers of animals in close quarters, are well known to be a perfect storm for the spread of CWD. Not to mention the fact that given the transactional nature of captive deer breeding, many animals are sold and shipped across wide swaths of the country, potentially cross-contaminating new herds of deer all along the way.
While there have been increasing amounts of testing and monitoring of these herds for CWD, the effectiveness of these efforts are feared to be sub-par at best. “The profit motive is so great, it is common for deer breeders to hide infections, or simply not test, and thus spread the disease,” writes Whit Fosborg, CEO of the Theodore Roosevelt Conservation Partnership.
All of this makes Texas a likely ground zero for future CWD issues, a perfect example being a 2021 investigation that identified the release of more than 1,700 deer from seven Texas captive deer facilities that could have been exposed to chronic wasting disease. “Overwhelmingly, the CWD hot zone maps radiate from captive facilities across the state,” said Texas resident and bowhunter K.C. Smith.
Furthermore, the proliferation of captive deer facilities and “canned shooting preserves” threaten to shine a poor light on the larger hunting public, potentially hemorrhaging support for the free-range pursuit of whitetails in Texas and elsewhere. While the vast majority of non-hunters support hunting for food, those figures reverse when considering “trophy hunting.” Animals that are custom-bred to grow the largest antlers possible and then housed in high-fenced small enclosures and sold off to be shot by the highest bidder represents the most egregious example of what trophy hunting could be percieved as. Regardless of whether or not most high-fence facilities fit this description, the worst offenders are unfortunately what most people notice. We as whitetail hunters risk being defined by our most fringe element, especially in the Lone Star state.
It’s important to note that many of the high fence deer facilities in Texas very well might be well-managed and owned by good honest deer-loving people, Smith was quick to remind me. This is not as cut and dry of an issue as some non-Texans want to believe it is.
“I have an easy set of values to live by: don’t hurt people and don’t take their stuff,” he said. “However, when the deer ‘owned’ by another person are threatening to take away the future of my kids’ and everyone’s deer hunting, something must be done.”
Support for the Chronic Wasting Disease Research and Management Act will help just as much here as in Wisconsin, as would advocating for greater oversightof the captive deer industry in Texas and beyond.
www.themeateater.com/wired-to-hunt/whitetail-management/4-most-endangered-whitetail-destinations-in-america
Detection of infectious prions in tissues of feral hogs
PAULINA SOTO1,2, Francisca Bravo-Risi3,4, Rebeca Benavente3, Michael J. Bodenchuk5, Patrick Whitley Whitley6, Clint Turnage6, Tracy A Nichols7, Terry Spraker, Vienna R Brown6, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile. 3Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Chile. 4Universidad Bernardo O’Higgins, Santigo, Chile. 5United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, San Antonio, USA. 6USDA APHIS Wildlife Services, Fort Collins, USA. 7Veterinary Services Cervid Health Program, United States Department of Agriculture, Animal and Plant Health Inspection Service, Fort Collins, USA
Abstract
Chronic wasting disease (CWD) is the prion disease with the greatest potential for spreading, affecting at least seven cervid species. An essential feature of prions lies in their ability to infect some species and not others. This phenomenon, known as a species barrier, seems to be largely dictated by the similarities between the donor (infectious) and recipient prion protein (PrP) sequences. Considering this, some potentially susceptible carnivores are proposed to act as vectors of CWD transmission as they may get infected. Alternatively, predators or scavengers may not get infected but spread infectious particles after they cross their digestive tracts. This project aims to identify the presence of infectious prions in feral hogs living in CWD-endemic areas. To do this, PMCA seeding activity was analyzed on feral hogs tissues such as the brain and retropharyngeal and submandibular lymph nodes using homologous pig PrP substrate or heterologous deer PrP substrate. We furthe! r injected selected feral hogs tissues into mice expressing the cervid and porcine versions of the prion protein to assess their potential to transmit disease. Our results show positive in vitro PrPSc detection using porcine and cervid substrates. The considerably higher detection using cervid substrate suggests that although feral hogs are exposed to CWD prions, disease transmission is inefficient. Bioassays confirmed these results and demonstrated that the infectivity carried by feral hogs is not enough to induce disease. In summary, these results suggest that feral hogs may play a role in disseminating CWD prions across the landscape.
***> In summary, these results suggest that feral hogs may play a role in disseminating CWD prions across the landscape.
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intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
THURSDAY, MARCH 08, 2018
WILD HOGS AND CHRONIC WASTING DISEASE CWD TSE PRION
i have been worried about this for some time, but i don't see why others are not worried as well. these feral hogs that run rampant across states, can dig up a great deal of territory. what else can they dig up? i.e. CWD TSE PRION, and can they spread cwd tse prion to hell and back?
CWD TO PIGS
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Location: Virus and Prion Research
Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Author item Moore, Sarah item Kunkle, Robert item Kondru, Naveen item Manne, Sireesha item Smith, Jodi item Kanthasamy, Anumantha item West Greenlee, M item Greenlee, Justin
Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:
Technical Abstract: Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study, neurological signs consistent with prion disease were observed only in one pig: an intracranially challenged pig that was euthanized at 64 months post-challenge. The purpose of this study was to use an antigen-capture immunoassay (EIA) and real-time quaking-induced conversion (QuIC) to determine whether PrPSc is present in lymphoid tissues from pigs challenged with the CWD agent.
Methods: At two months of age, crossbred pigs were challenged by the intracranial route (n=20), oral route (n=19), or were left unchallenged (n=9). At approximately 6 months of age, the time at which commercial pigs reach market weight, half of the pigs in each group were culled (<6 challenge="" groups="" month="" pigs="" remaining="" the="">6 month challenge groups) were allowed to incubate for up to 73 months post challenge (mpc). The retropharyngeal lymph node (RPLN) was screened for the presence of PrPSc by EIA and immunohistochemistry (IHC). The RPLN, palatine tonsil, and mesenteric lymph node (MLN) from 6-7 pigs per challenge group were also tested using EIA and QuIC.
Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was="">6 months group, 5/6 pigs in the oral <6 4="" and="" group="" months="" oral="">6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). Conclusions:
This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge.
CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease.
Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
www.ars.usda.gov/research/publications/publication/?seqNo115=337105
CONFIDENTIAL
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
web.archive.org/web/20031026000118/www.bseinquiry.gov.uk/files/yb/1990/08/23004001.pdf
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
web.archive.org/web/20030822031154/www.bseinquiry.gov.uk/files/yb/1990/09/10007001.pdf
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
web.archive.org/web/20030822054419/www.bseinquiry.gov.uk/files/yb/1990/09/21009001.pdf
snip...see much more here ;
WEDNESDAY, APRIL 05, 2017
Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Snip…see;
chronic-wasting-disease.blogspot.com/2017/04/disease-associated-prion-protein.html
THURSDAY, MARCH 08, 2018
Cervid, Wild Hogs, Coyotes, Wolves, Cats, Rodents, Gut Piles and Scavengers, A Potential Risk as Regards Disease Transmission CWD TSE Prion
chronic-wasting-disease.blogspot.com/2018/03/cervid-wild-hogs-coyotes-wolves-cats.html
TUESDAY, JUNE 27, 2023
USAHA Report of the Subcommittee on Farmed Cervidae CWD TSE Prion Herds 2015 to 2023
chronic-wasting-disease.blogspot.com/2023/06/usaha-report-of-subcommittee-on-farmed.html
prpsc.proboards.com/thread/128/usaha-reports-farmed-cervidae-herds
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
Paulina Sotoa,b, J. Hunter Reedc, Mitch Lockwoodc, and Rodrigo Moralesa,b aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile; cTexas Parks and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy affecting captive and free-ranging cervids (e.g., mule deer, white-tailed deer, elk, reindeer, and moose). Nowadays, CWD is widely distributed in North America. It is suggested that CWD spreads due to direct animal contact or through exposure to contaminated environments previously inhabited by infected animals. CWD may also be spread through the movement of infected animals and carcasses. Taxidermy practices involve processing deer tissues (or whole animal carcasses). In many cases, the CWD status of processed animals is unknown. This can generate risks of disease spread and transmission. Taxidermy practices include different steps involving physical, chemical, and biological procedures. Without proper tissue handling or disposal practices, taxidermist facilities may become a focus of prion infectivity.
Aims: In this study, we evaluated the presence of infectious prions in a taxidermy facility believed to be exposed to CWD. Detection was performed using the Protein Misfolding Cyclic Amplification (PMCA) technique in biological and inert environmental samples.
Methods: We collected biological and environmental samples (plants, soils, insects, excreta, and others) from a taxidermy facility, and we tested these samples using the PMCA technique. In addition, we swabbed different surfaces possibly exposed to CWD-infected animals. For the PMCA reaction, we directly used a swab piece or 10 µL of 20% w/v homogenized samples. Results: The PMCA analysis demonstrated CWD seeding activity in some of the components of this facility, including insects involved in head processing, soils, and a trash dumpster.
Conclusions: Different areas of this property were used for various taxidermy procedures. We were able to detect the presence of prions in
i) soils that were in contact with the heads of dead animals,
ii) insects involved in the cleaning of skulls, and
iii) an empty dumpster where animal carcasses were previously placed.
This is the first report demonstrating that swabbing is a helpful method to screen for prion infectivity on surfaces potentially contaminated with CWD. These findings are relevant as this swabbing and amplification strategy may be used to evaluate the disease status of other free-ranging and captive settings where there is a concern for CWD transmissions, such as at feeders and water troughs with CWD-exposed properties. This approach could have substantial implications for free-ranging cervid surveillance as well as in epidemiological investigations of CWD.
Funded by: USDA Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Carrot plants as potential vectors for CWD transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Claudio Sotoa, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile
Prion diseases are infectious neurodegenerative disorders afflicting humans and other mammals. These diseases are generated by the misfolding of the cellular prion protein into a disease-causing isoform. Chronic wasting disease (CWD) is a prevalent prion disease affecting cervids (captive and free-range). CWD is thought to be transmitted through direct animal contact or by indirect exposure to contaminated environments. Many studies have shown that infectious prions can enter the environment through saliva, feces, or urine from infected animals and decaying carcasses. However, we do not fully understand the specific contribution of each component to disease transmission events. Plants are logical environmental components to be evaluated since they grow in environments contaminated with CWD prions and are relevant for animal and human nutrition.
Aims: The main objective of this study is to study whether prions are transported to the roots and leaves of carrots, an edible plant commonly used in the human diet and as deer bait.
Methods: We have grown carrot plants in CWD-infected soils. After 90 days, we harvested the carrots and separated them from the leaves. The experiment was controlled by growing plants in soil samples treated with brain extracts from healthy animals. These materials were interrogated for their prion seeding activity using the Protein Misfolding Cyclic Amplification (PMCA) technique. Infectivity was evaluated in mouse bioassays (intracerebral injections in Tg1536 mice). The animals were sacrificed when they showed established signs of prion disease. Animals not displaying clinical signs were sacrificed at 600 days post-inoculation.
Results: The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions, as well as in carrot plants (leaves and roots) grown on them. Bioassays demonstrated that both leaves and roots contained CWD prions in sufficient quantities to induce disease (92% attack rate). As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. Animals treated with soil and plant components exposed with CWD-free brain extracts did not display prion-associated clinical signs or evidence of sub-clinical prion infection.
Conclusions: We show that edible plant components can absorb prions from CWD contaminated soils and transport them to their aerial parts. Our results indicate that plants could participate as vectors of CWD transmission. Importantly, plants designated for human consumption represent a risk of introducing CWD prions into the human food chain.
Funded by: NIH
Grant number: R01AI132695
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
October 6th-12th, 126th Meeting 2022 Resolutions
RESOLUTION NUMBER: 30 Approved
SOURCE: COMMITTEE ON WILDLIFE
SUBJECT MATTER: Chronic Wasting Disease Carcass Disposal Dumpster Management and Biosecurity
BACKGROUND INFORMATION:
State and tribal wildlife agencies may identify collection points (dumpsters) within an identified chronic wasting disease (CWD) management zone for the disposal of hunter-harvested cervid carcasses to remove potentially infected carcasses off the landscape for disposal by an approved method (Gillin & Mawdsley, 2018, chap.14). However, depending on their placement and maintenance these dumpsters could potentially increase the risk of CWD transmission.
In several different states, photographic evidence has shown dumpsters in state identified CWD management zones overflowing with deer carcasses and limbs scattered on the land nearby. This could provide an opportunity for scavengers to potentially move infected carcass material to non-infected zones or increase contamination of the ground material around the dumpster’s location.
Federal guidance does not explicitly address uniform standards for collection locations for carcasses of free-ranging cervids; however, the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services Program Standards on CWD outlines procedures for carcass disposal, equipment sanitation, and decontamination of premises for captive cervid facilities.
RESOLUTION:
The United States Animal Health Association urges the Association of Fish and Wildlife Agencies (AFWA), Wildlife Health Committee to further refine the AFWA Technical Report on Best Management Practices for Prevention, Surveillance, and Management of Chronic Wasting Disease; Chapter 14, Carcass Disposal to address the placement and management of chronic wasting disease carcass disposal dumpsters or other carcass collection containers.
Reference:
1. Gillin, Colin M., and Mawdsley, Jonathan R. (eds.). 2018. AFWA Technical Report on Best Management Practices for Surveillance, Management and Control of Chronic Wasting Disease. Association of Fish and Wildlife Agencies, Washington, D. C. 111 pp.
www.usaha.org/upload/Resolution/2022/2022_Resolution_30_CWD_Dumpste.pdf
ENVIRONMENT FACTORS FOR THE TRANSMISSION OF CWD TSE PRP
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Environment International
Available online 13 June 2022, 107347
Environment International
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Qi Yuana Gag e Rowdenb Tiffany M.Wolfc Marc D.Schwabenlanderb Peter A.LarsenbShannon L.Bartelt-Huntd Jason C.Bartza
a Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178, United States of America
b Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN, 55108, United States of America
c Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, MN, 55108, United States of America
d Department of Civil and Environmental Engineering, Peter Kiewit Institute, University of Nebraska-Lincoln, Omaha, Nebraska, 68182, United States of America
Received 26 April 2022, Revised 8 June 2022, Accepted 9 June 2022, Available online 13 June 2022.
doi.org/10.1016/j.envint.2022.107347
Get rights and content
Under a Creative Commons license Open access
Highlights • An innovative method for prion recovery from swabs was developed.
• Recovery of prions decreased as swab-drying time was increased.
• Recovery of CWD prions from stainless steel and glass was approximately 30%.
• RT-QuIC enhanced CWD prion detection by 4 orders of magnitude.
• Surface-recovered CWD prion was sufficient for efficient RT-QuIC detection.
Abstract
Chronic wasting disease (CWD) has been identified in 30 states in the United States, four provinces in Canada, and recently emerged in Scandinavia. The association of CWD prions with environmental materials such as soil, plants, and surfaces may enhance the persistence of CWD prion infectivity in the environment exacerbating disease transmission. Identifying and quantifying CWD prions in the environment is significant for prion monitoring and disease transmission control. A systematic method for CWD prion quantification from associated environmental materials, however, does not exist. In this study, we developed an innovative method for extracting prions from swabs and recovering CWD prions swabbed from different types of surfaces including glass, stainless steel, and wood. We found that samples dried on swabs were unfavorable for prion extraction, with the greatest prion recovery from wet swabs. Using this swabbing technique, the recovery of CWD prions dried to glass or stainless steel was approximately 30% in most cases, whereas that from wood was undetectable by conventional prion immunodetection techniques. Real-time quake-induced conversion (RT-QuIC) analysis of these same samples resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this method was similar to the original CWD prion load applied to the surface. This combined surface swabbing and RT-QuIC detection method provides an ultrasensitive means for prion detection across many settings and applications.
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5. Conclusions
Chronic wasting disease is spreading in North America and it is hypothesized that in CWD-endemic areas environmental persistence of CWD prions can exacerbate disease transmission. The development of a sensitive CWD prion detection method from environmentally relevant surfaces is significant for monitoring, risk assessment, and control of CWD. In this study, we developed a novel swab-extraction procedure for field deployable sampling of CWD prions from stainless steel, glass, and wood. We found that extended swab-drying was unfavorable for extraction, indicating that hydrated storage of swabs after sampling aided in prion recovery. Recoverable CWD prions from stainless steel and glass was approximately 30%, which was greater than from wood. RT-QuIC analysis of the swab extracts resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude compared to conventional immunodetection techniques. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this developed method was similar to the original CWD prion load without surface contact. This method of prion sampling and recovery, in combination with ultrasensitive detection methods, allows for prion detection from contaminated environmental surfaces.
www.sciencedirect.com/science/article/pii/S0160412022002744?via%3Dihub
Research Paper
Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer
Anthony Ness, Aradhana Jacob, Kelsey Saboraki, Alicia Otero, Danielle Gushue, Diana Martinez Moreno, Melanie de Peña, Xinli Tang, Judd Aiken, Susan Lingle & Debbie McKenzie ORCID Icon show less
Pages 40-57 | Received 03 Feb 2022, Accepted 13 May 2022, Published online: 29 May 2022
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doi.org/10.1080/19336896.2022.2079888
ABSTRACT
Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.
KEYWORDS: Prion chronic wasting diseasesex differences species differences disease prevalence cervid protein expression glands
www.tandfonline.com/doi/full/10.1080/19336896.2022.2079888
Paper
Rapid recontamination of a farm building occurs after attempted prion removal
Kevin Christopher Gough BSc (Hons), PhD Claire Alison Baker BSc (Hons) Steve Hawkins MIBiol Hugh Simmons BVSc, MRCVS, MBA, MA Timm Konold DrMedVet, PhD, MRCVS … See all authors
First published: 19 January 2019 doi.org/10.1136/vr.105054
The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease.
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This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.
bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
pubmed.ncbi.nlm.nih.gov/30602491/
***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years
***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.
JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12
Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free
Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3
www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82011-0
Front. Vet. Sci., 14 September 2015 | doi.org/10.3389/fvets.2015.00032
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
imageTimm Konold1*, imageStephen A. C. Hawkins2, imageLisa C. Thurston3, imageBen C. Maddison4, imageKevin C. Gough5, imageAnthony Duarte1 and imageHugh A. Simmons1
The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.
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Discussion
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In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination.
journal.frontiersin.org/article/10.3389/fvets.2015.00032/full
***> 172. Establishment of PrPCWD extraction and detection methods in the farm soil
Kyung Je Park, Hoo Chang Park, In Soon Roh, Hyo Jin Kim, Hae-Eun Kang and Hyun Joo Sohn
Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon, Gyeongsangbuk-do, Korea
Conclusions: Our studies showed that PrPCWD persist in 0.001% CWD contaminated soil for at least 4 year and natural CWD-affected farm soil. When cervid reintroduced into CWD outbreak farm, the strict decontamination procedures of the infectious agent should be performed in the environment of CWD-affected cervid habitat.
www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
THE tse prion aka mad cow type disease is not your normal pathogen.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
***> that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]
www.ncbi.nlm.nih.gov/pubmed/8006664?dopt=Abstract
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
www.pnas.org/content/97/7/3418.full
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
www.ncbi.nlm.nih.gov/pmc/articles/PMC2493038/
MONDAY, APRIL 19, 2021
Evaluation of the application for new alternative biodiesel production process for rendered fat including Category 1 animal by-products (BDI-RepCat® process, AT)
transmissiblespongiformencephalopathy.blogspot.com/2021/04/evaluation-of-application-for-new.html
Detection of protease-resistant cervid prion protein in water from a CWD-endemic area
https://www.ncbi...nlm.nih.gov/pmc/articles/PMC2802782/pdf/prion0303_0171.pdf
A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing
onlinelibrary.wiley.com/doi/10.1111/j.1539-6924.2012.01922.x/abstract
Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals
bmcvetres.biomedcentral.com/track/pdf/10.1186/1746-6148-9-134.pdf
THURSDAY, FEBRUARY 28, 2019
BSE infectivity survives burial for five years with only limited spread
link.springer.com/content/pdf/10.1007%2Fs00705-019-04154-8.pdf
5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!
QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !
FRIDAY, APRIL 30, 2021
Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?
***> Confidential!!!!
***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
and so it seems...
Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years
Published: May 9, 2007
snip...
Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field.
snip...
journals.plos.org/plosone/article?id=10.1371/journal.pone.0000435
Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document
web.archive.org/web/20090505211734/http://www.bseinquiry.gov.uk/files/sc/Seac07/tab03.pdf
Published: 06 September 2021
***> Chronic wasting disease: a cervid prion infection looming to spillover
Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie
Veterinary Research volume 52, Article number: 115 (2021)
veterinaryresearch.biomedcentral.com/articles/10.1186/s13567-021-00986-y
CHRONIC WASTING DISEASE CWD TSE PrP ZOONOSIS ZOONOTIC RISK HUMANS
17 DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.
Rebeca Benavente1, Francisca Bravo1,2, Paulina Soto1,2, J. Hunter Reed3, Mitch Lockwood3, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile. 3Texas Parks and Wildlife, Austin, USA
Abstract
The zoonotic potential of chronic wasting disease (CWD) remains unknown. Currently, there are no known natural cases of CWD transmission to humans but increasing evidence suggests that the host range of CWD is not confined only to cervid species. Alarmingly, recent experimental evidence suggests that certain CWD isolates can induce disease in non-human primates. While the CDC strongly recommends determining CWD status in animals prior to consumption, this practice is voluntary. Consequently, it is plausible that a proportion of the cervid meat entering the human food chain may be contaminated with CWD. Of additional concern is that traditional diagnostic techniques used to detect CWD have relatively low sensitivity and are only approved for use in tissues other than those typically ingested by humans. In this study, we analyzed different processed meats derived from a pre-clinical, CWD-positive free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats. CWD-prion presence in these products were assessed by PMCA using deer and elk substrates. Our results show positive prion detection in all products. To confirm the resilience of CWD-prions to traditional cooking methods, we grilled and boiled the meat products and evaluated them for any remnant PMCA seeding activity. Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking. Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
***> Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats.
***> CWD-prion presence in these products were assessed by PMCA using deer and elk substrates.
***> Our results show positive prion detection in all products.
***> Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking.
***> Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
=====
9 Carrot plants as potential vectors for CWD transmission.
Paulina Soto1,2, Francisca Bravo-Risi1,2, Claudio Soto1, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile
***> We show that edible plant components can absorb prions from CWD-contaminated soils and transport them to their aerial parts.
***> Our results indicate that edible plants could participate as vectors of CWD transmission.
=====
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaoui1,2, Ginny Cheng1,2, Wiebke Wemheuer3, Walter Schulz-Schaeffer3, Sabine Gilch1,2, Hermann Schatzl1,2 1University of Calgary, Calgary, Canada. 2Calgary Prion Research Unit, Calgary, Canada. 3Institute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
***> Further passage to cervidized mice revealed transmission with a 100% attack rate.
***> Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.
****> The disease manifested as atypical in macaques and initial transgenic mouse transmissions, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
***> Epidemiologic surveillance of prion disease among cervid hunters and people likely to have consumed venison contaminated with chronic wasting disease
=====
Efficient CWD-like transmission of splenic prions in cervidized transgenic mice: a probable diagnostic marker for CWD infection in humans
Xu Qi, Liuting Qing, Manuel Camacho, Ignazio Cali, Qingzhong Kong
Department of Pathology, Case Western Reserve University, Cleveland, USA
***> Such experimentally generated splenic “humanized” CWD prions (termed eHuCWDsp) appear indistinguishable from prions in the brain of sCJDMM1 patients on Western blot.
=====END
I HAVE NOT READ ALL THESE, BUT THOUGHT SOME OF YOU MIGHT FIND THIS INTERESTING!
kind regards, terry
intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
TEXAS CWD 2023
WEDNESDAY, JUNE 14, 2023
Texas TPWD CWD 508 Cases Confirmed To Date
chronic-wasting-disease.blogspot.com/2023/06/texas-tpwd-cwd-508-cases-confirmed-to.html
***> TEXAS HISTORY OF CWD <***
Singeltary telling TAHC, that CWD was waltzing into Texas from WSMR around Trans Pecos region, starting around 2001, 2002, and every year, there after, until New Mexico finally shamed TAHC et al to test where i had been telling them to test for a decade. 2012 cwd was detected first right there where i had been trying to tell TAHC for 10 years.
***> Singeltary on Texas Chronic Wasting Disease CWD TSE Prion History <***
chronic-wasting-disease.blogspot.com/2017/08/texas-chronic-wasting-disease-cwd-tse.html
TUESDAY, JUNE 27, 2023
USAHA Report of the Subcommittee on Farmed Cervidae CWD TSE Prion Herds 2015 to 2023
chronic-wasting-disease.blogspot.com/2023/06/usaha-report-of-subcommittee-on-farmed.html
prpsc.proboards.com/thread/128/usaha-reports-farmed-cervidae-herds
2023 CWD ZOONOSIS
***> Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.<***
PART 2. TPWD CHAPTER 65. DIVISION 1. CWD
31 TAC §§65.82, 65.85, 65.88
The Texas Parks and Wildlife Commission in a duly noticed meeting on May 25, 2023 adopted amendments to 31 TAC §§65.82, 65.85, and §65.88, concerning Disease Detection and Response, without changes to the proposed text as published in the April 21, 2023, issue of the Texas Register (48 TexReg 2048). The rules will not be republished.
Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.
www.sos.texas.gov/texreg/archive/June302023/Adopted%20Rules/31.NATURAL%20RESOURCES%20AND%20CONSERVATION.html#57
U of M expert warns of increasing likelihood of CWD transmission to humans
Cathy Wurzer and Gretchen Brown June 5, 2023 1:30 PM
Minnesota scientists have watched chronic wasting disease (CWD) — a fatal, neurological illness — kill deer and elk.
Now, they’re studying its potential to jump to humans.
The University of Minnesota’s Center for Infectious Disease Research and Policy has received more than $1.5 million in state money to start prepping for the possibility of CWD spreading to cows, pigs and possibly humans.
Michael Osterholm, Ph.D. is a world-renowned epidemiologist who heads the center.
He said transmission to humans has not yet been confirmed, but research suggests it is increasingly likely — especially as the disease continues to spread among deer and elk.
“None of us want to believe this could happen,” he told MPR News host Cathy Wurzer. “But you know, as much as you hope it isn't going to happen, hope is not a strategy.”
Current testing can be done only if animals die or are killed, and lymph nodes or brain matter is removed for testing to verify the disease.
That means captive deer often aren’t tested until they die or show symptoms of the disease, and that’s often too late to stop the spread of the disease.
And there aren’t yet adequate tests for humans, Osterholm said — let alone protocols in place if a human were to test positive for the disease.
snip...see;
U of M expert warns of increasing likelihood of CWD transmission to humans
Published: 22 August 2022
www.mprnews.org/episode/2023/06/05/chronic-wasting-disease-in-humans-us-osterholm-prepares-for-whatif?
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bUniversité Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France; cDepartment of Biological Sciences, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
Aims: Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we aimed to determine the zoonotic potential of CWD using a mouse model for human prion diseases.
Material and Methods: Transgenic mice overexpressing human PrPChomozygous for methionine at codon 129 (tg650) were inoculated intracerebrally with brain homogenates of white-tailed deer infected with Wisc-1/CWD1 or 116AG CWD strains. Mice were monitored for clinical signs and were euthanized at terminal disease. Brains were tested by RT-QuIC, western blot upon PK digestion, and immunohistochemistry; fecal homogenates were analyzed by RT-QuIC. Brain/spinal cord and fecal homogenates of CWD-inoculated tg650 mice were inoculated into tg650 mice or bank voles. Brain homogenates of bank voles inoculated with fecal homogenates of CWD-infected tg650 mice were used for second passage in bank voles.
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650 brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
Funded by: We are grateful for financial support from the Natural Sciences and Engineering Research Council of Canada, the National Institutes of Health, Genome Canada, and the Alberta Prion Research Institute. SG is supported by the Canada Research Chairs program.
Acknowledgement: We thank Dr. Trent Bollinger, WCVM, University of Saskatchewan, Saskatoon, Canada, for providing brain tissue from the WTD-116AG isolate, Dr. Stéphane Haïk, ICM, Paris, France, for providing brain tissue from vCJD and sCJD cases, and Dr. Umberto Agrimi, Istituto Superiore di Sanità, Italy, for the bank vole model. We thank animal facility staff for animal care, Dr. Stephanie Anderson for veterinary oversight, and Yo-Ching Cheng for preparing recombinant PrP substrates. Thank you to Dr. Stephanie Booth and Jennifer Myskiw, Public Health Agency of Canada, Canada.
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
actaneurocomms.biomedcentral.com/counter/pdf/10.1186/s40478-021-01262-y.pdf
P35
ADAPTATION OF CHRONIC WASTING DISEASE (CWD) INTO HAMSTERS, EVIDENCE OF A WISCONSIN STRAIN OF CWD
Chad Johnson1, Judd Aiken2,3,4 and Debbie McKenzie4,5 1 Department of Comparative Biosciences, University of Wisconsin, Madison WI, USA 53706 2 Department of Agriculture, Food and Nutritional Sciences, 3 Alberta Veterinary Research Institute, 4.Center for Prions and Protein Folding Diseases, 5 Department of Biological Sciences, University of Alberta, Edmonton AB, Canada T6G 2P5
The identification and characterization of prion strains is increasingly important for the diagnosis and biological definition of these infectious pathogens. Although well-established in scrapie and, more recently, in BSE, comparatively little is known about the possibility of prion strains in chronic wasting disease (CWD), a disease affecting free ranging and captive cervids, primarily in North America. We have identified prion protein variants in the white-tailed deer population and demonstrated that Prnp genotype affects the susceptibility/disease progression of white-tailed deer to CWD agent. The existence of cervid prion protein variants raises the likelihood of distinct CWD strains. Small rodent models are a useful means of identifying prion strains. We intracerebrally inoculated hamsters with brain homogenates and phosphotungstate concentrated preparations from CWD positive hunter-harvested (Wisconsin CWD endemic area) and experimentally infected deer of known Prnp genotypes. These transmission studies resulted in clinical presentation in primary passage of concentrated CWD prions. Subclinical infection was established with the other primary passages based on the detection of PrPCWD in the brains of hamsters and the successful disease transmission upon second passage. Second and third passage data, when compared to transmission studies using different CWD inocula (Raymond et al., 2007) indicate that the CWD agent present in the Wisconsin white-tailed deer population is different than the strain(s) present in elk, mule-deer and white-tailed deer from the western United States endemic region.
www.istitutoveneto.it/prion_09/Abstracts_09.pdf
PRION CONFERENCE 2009
Prion special issue related to the III International Symposium on “The New Prion Biology
www.tandfonline.com/doi/pdf/10.4161/pri.3.4.10772?needAccess=true
www.tandfonline.com/toc/kprn20/3/4?nav=tocList
www.neuroprion.org/
www.certh.gr/dat/EED86597/file.pdf
UPDATE CWD ZOONOSIS AND THE WISCONSIN STRAIN
SUNDAY, APRIL 9, 2023
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
SEE A FEW HIGHLIGHTS;
''Here, we provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model.''
''Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission.'' ''These findings have strong implications for public health and CWD management.''
''We demonstrate that this transgenic line was susceptible to infection with CWD prions and displayed a distinct leading clinical sign, an atypical PrPSc signature and unusual fecal shedding of infectious prions.''
''Importantly, these prions generated by the human PrP transgenic mice were transmissible upon passage.''
Our results are the first evidence of a zoonotic risk of CWD when using one of the most common CWD strains, Wisc-1/CWD1 for ''infection. ''
''Our findings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.''
''Indeed, such heterogeneity and distinct seeding activities and infectivity of abnormal PrP fragments was observed in VPSPr cases [20, 43].''
''This implies a high risk of exposure to this strain, e.g., through consumption or handling of infected carcasses, in contrast to rarer CWD strains, and therefore, an actual risk for human health.''
''Fecal shedding of infectious prions, if it occurs in humans, is particularly concerning because of potential human-to-human transmission and adaptation of hCWD.''
Overall, our findings suggest that CWD surveillance in humans should encompass a wider spectrum of tissues/organs tested and include new criteria in the diagnosis of potential patients.
***> PLEASE NOTE;
''Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease-sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and in the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defned by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C- and N-termini, with a molecular weight between 6 and 8 kDa [24, 44–46]. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7–8 kDa fragment (Figs. 2, 4) are very similar to that of GSS, both in terms of migration profle and the N-terminal cleavage site.''
snip...
''CWD in humans might remain subclinical but with PrPSc deposits in the brain with an unusual morphology that does not resemble the patterns usually seen in different prion diseases (e.g., mouse #328; Fig. 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063; Fig. 4), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable. Here, humanized mice inoculated with CWD deer isolates had an atypical onset of the disease with myoclonus (93.75%), before presenting typical clinical signs, generating prions that presented with either atypical biochemical signature (#321 and #3063), shed in feces (#327), or were undetectable by the classical detection methods. The fact that we could not establish a strong correlation between disease manifestation in tg650 mice inoculated with Wisc-1- or 116AG-CWD and the presence of abnormal PrP (Western blot, IHC or RTQuIC) might be explained by the presence of heterogeneous prions in the brains of infected mice with diferent seeding properties in vitro. Indeed, such heterogeneity and distinct seeding activities and infectivity of abnormal PrP fragments was observed in VPSPr cases [20, 43].''
VPSPr, GSS, and CWD zoonosis, concerns there from, where did i hear this concern before?
1. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
link.springer.com/article/10.1007/s00401-022-02482-9
efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
transmissiblespongiformencephalopathy.blogspot.com/2023/04/transmission-of-cervid-prions-to.html
Heterozygosity for cervid S138N polymorphism results in subclinical CWD in gene-targeted mice and progressive inhibition of prion conversion
HIGHLIGHT
However, prion seeding activity was detected in spleens, brains, and feces of these mice, suggesting subclinical infection accompanied by prion shedding.
Infected animals accumulate prions in lymphoreticular and other peripheral tissues, e.g., skeletal muscle, and shed infectious prions in saliva, urine and feces, contributing to direct and environmental transmission and rapidly increasing geographic distribution of CWD (9–12).
However, prion-seeding activity was detectable in the brain, spleen, and feces, indicating subclinical infection and potential for contagiousness.
Heterozygosity for cervid S138N polymorphism results in subclinical CWD in gene-targeted mice and progressive inhibition of prion conversion
Maria I. Arifin orcid.org/0000-0003-2042-3492, Lech Kaczmarczyk orcid.org/0000-0003-2747-3134, Doris Zeng orcid.org/0009-0002-2512-6227, +7, and Sabine Gilch orcid.org/0000-0001-5923-3464 sgilch@ucalgary.caAuthors Info & Affiliations Edited by Reed Wickner, NIH, Bethesda, MD;
received December 12, 2022; accepted March 6, 2023
April 4, 2023
120 (15) e2221060120
doi.org/10.1073/pnas.2221060120
Significance
Amino acid substitutions within the cervid prion protein (PrP) can decrease susceptibility to chronic wasting disease, generally with more prominent effects in homozygous animals. Using novel gene-targeted mouse models expressing S138N reindeer/caribou PrP, we demonstrate subclinical infection with prion seeding activity in spleen and fecal prion shedding in heterozygous 138SN and homozygous 138NN mice. A lower percentage of heterozygous 138SN-PrP than homozygous 138NN-PrP expressing mice harbored seeding-efficient prions in tissues. This is caused by dominant-negative interference of the PrP variants occurring only if they are coexpressed. Our findings are relevant to inform conservation efforts for caribou, an endangered species in North America. Furthermore, our study provides new mechanistic insights into genetic resistance and dominant-negative interference of conversion-competent PrP variants.
Abstract
Prions are proteinaceous infectious particles that replicate by structural conversion of the host-encoded cellular prion protein (PrPC), causing fatal neurodegenerative diseases in mammals. Species-specific amino acid substitutions (AAS) arising from single nucleotide polymorphisms within the prion protein gene (Prnp) modulate prion disease pathogenesis, and, in several instances, reduce susceptibility of homo- or heterozygous AAS carriers to prion infection. However, a mechanistic understanding of their protective effects against clinical disease is missing. We generated gene-targeted mouse infection models of chronic wasting disease (CWD), a highly contagious prion disease of cervids. These mice express wild-type deer or PrPC harboring the S138N substitution homo- or heterozygously, a polymorphism found exclusively in reindeer (Rangifer tarandus spp.) and fallow deer (Dama dama). The wild-type deer PrP-expressing model recapitulated CWD pathogenesis including fecal shedding. Encoding at least one 138N allele prevented clinical CWD, accumulation of protease-resistant PrP (PrPres) and abnormal PrP deposits in the brain tissue. However, prion seeding activity was detected in spleens, brains, and feces of these mice, suggesting subclinical infection accompanied by prion shedding. 138N-PrPC was less efficiently converted to PrPres in vitro than wild-type deer (138SS) PrPC. Heterozygous coexpression of wild-type deer and 138N-PrPC resulted in dominant-negative inhibition and progressively diminished prion conversion over serial rounds of protein misfolding cyclic amplification. Our study indicates that heterozygosity at a polymorphic Prnp codon can confer the highest protection against clinical CWD and highlights the potential role of subclinical carriers in CWD transmission.
snip...
To conclude, our study demonstrates that CWD-infected animals harboring S138N PrP might be “silent spreaders” of CWD prions and highlights the importance of lymphatic tissues in the detection of CWD, particularly in caribou, even in the absence of clinical manifestation. It is important to keep in mind that even protective genotypes may be permissive to certain minor or newly emerging CWD strains. Our results provide new mechanistic insights into dominant-negative inhibition of prion conversion, the tissue specificity of this effect, and suggests that PrPC primary structure is a determinant for tissue-specific prion replication.
www.pnas.org/doi/10.1073/pnas.2221060120
Saturday, April 9, 2022
EFSA EU Request for a scientific opinion on the monitoring of Chronic Wasting Disease (CWD) EFSA-Q-2022-00114 M-2022-00040 Singeltary Submission
efsaopinioncwd.blogspot.com/2022/04/efsa-eu-request-for-scientific-opinion.html
Published: 06 September 2021
***> Chronic wasting disease: a cervid prion infection looming to spillover
Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie
Veterinary Research volume 52, Article number: 115 (2021)
veterinaryresearch.biomedcentral.com/articles/10.1186/s13567-021-00986-y
PRION CONFERENCE 2022 ABSTRACTS CWD TSE PrP ZOONOSIS
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaouia, Ginny Chenga, Wiebke Wemheuerb, Walter J. Schulz-Schaefferb, Sabine Gilcha, and Hermann M. Schätzla aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine & Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bInstitute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
Aims: Chronic wasting disease (CWD) is a prion disease of cervids. Its rapid geographic expansion, shedding of infectivity and persistence in the environment for many years are of concern for humans. Here, we provide the first evidence by transmission experiments to different transgenic mouse models and bank voles that Cynomolgus macaques inoculated via different routes with CWD-positive cervid tissues harbor infectious prions that elicit clinical disease in rodents.
Material and Methods: We used tissue materials from macaques inoculated with CWD to inoculate transgenic mice overexpressing cervid PrPCfollowed by transmission into bank voles. We used RT-QuIC, immunoblot and PET blot analysis to assess brains, spinal cords, and tissues of the gastrointestinal tract (GIT) for the presence of prions.
Results: Our results show that of the macaque materials that induced clinical disease in transgenic mice,73% were from the CNS (46% spinal cord and 27% brain), and 27% were from the spleen, although attack rates were low around 20%. Clinical mice did not display PK-resistant PrPSc(PrPres) in immunoblot, but showed low-levels of prion seeding activity. Transmission into bank voles from clinical transgenic mice led to a 100% attack rate with typical PrPressignature in immunoblot, which was different from that of voles inoculated directly with CWD or scrapie prions. High-level prion seeding activity in brain and spinal cord and PrPresdeposition in the brain were present. Remarkably, we also found prion seeding activity in GIT tissues of inoculated voles. Second passage in bank voles led to a 100% attack rate in voles inoculated with brain, spinal cord and small intestine material from first round animals, with PrPresin immunoblot, prion seeding activity, and PrPresdeposition in the brain. Shortened survival times indicate adaptation in the new host. This also shows that prions detected in GIT tissues are infectious and transmissible. Transmission of brain material from sick voles back to cervidized mice revealed transmission in these mice with a 100% attack rate, and interestingly, with different biochemical signature and distribution in the brain.
Conclusions: Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including oral one. The disease manifested as atypical in macaques and transgenic mice, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
Funded by: The National Institutes of Health, USA, and the Alberta Prion Research Institute/Alberta Innovates Canada. Grant number: 1R01NS121016-01; 201,600,023
Acknowledgement: We thank Umberto Agrimi, Istituto Superiore di Sanità, Rome, Italy, and Michael Beekes, Robert-Koch Institute Berlin, Germany, for providing the bank vole model. We thank the University of Calgary animal facility staff and Dr. Stephanie Anderson for animal care.
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bUniversité Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France; cDepartment of Biological Sciences, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
Aims: Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we aimed to determine the zoonotic potential of CWD using a mouse model for human prion diseases.
Material and Methods: Transgenic mice overexpressing human PrPChomozygous for methionine at codon 129 (tg650) were inoculated intracerebrally with brain homogenates of white-tailed deer infected with Wisc-1/CWD1 or 116AG CWD strains. Mice were monitored for clinical signs and were euthanized at terminal disease. Brains were tested by RT-QuIC, western blot upon PK digestion, and immunohistochemistry; fecal homogenates were analyzed by RT-QuIC. Brain/spinal cord and fecal homogenates of CWD-inoculated tg650 mice were inoculated into tg650 mice or bank voles. Brain homogenates of bank voles inoculated with fecal homogenates of CWD-infected tg650 mice were used for second passage in bank voles.
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650 brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
Funded by: We are grateful for financial support from the Natural Sciences and Engineering Research Council of Canada, the National Institutes of Health, Genome Canada, and the Alberta Prion Research Institute. SG is supported by the Canada Research Chairs program.
Acknowledgement: We thank Dr. Trent Bollinger, WCVM, University of Saskatchewan, Saskatoon, Canada, for providing brain tissue from the WTD-116AG isolate, Dr. Stéphane Haïk, ICM, Paris, France, for providing brain tissue from vCJD and sCJD cases, and Dr. Umberto Agrimi, Istituto Superiore di Sanità, Italy, for the bank vole model. We thank animal facility staff for animal care, Dr. Stephanie Anderson for veterinary oversight, and Yo-Ching Cheng for preparing recombinant PrP substrates. Thank you to Dr. Stephanie Booth and Jennifer Myskiw, Public Health Agency of Canada, Canada.
The chronic wasting disease agent from white-tailed deer is infectious to humanized mice after passage through raccoons
Eric Cassmanna, Xu Qib, Qingzhong Kongb, and Justin Greenleea
aNational Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, IA, USA bDepartments of Pathology, Neurology, National Center for Regenerative Medicine, and National Prion Disease Pathology Surveillance Center, Case Western Reserve University, Cleveland, Ohio, USA
Aims: Evaluate the zoonotic potential of the raccoon passaged chronic wasting disease (CWD) agent in humanized transgenic mice in comparison with the North American CWD agent from the original white-tailed deer host.
Material and Methods: Pooled brain material (GG96) from a CWD positive herd was used to oronasally inoculate two white-tailed deer with wild-type prion protein genotype and intracranially inoculate a raccoon. Brain homogenates (10% w/v) from the raccoon and the two white-tailed deer were used to intracranially inoculate separate groups of transgenic mice that express human prion protein with methionine (M) at codon 129 (Tg40h). Brains and spleens were collected from mice at experimental endpoints of clinical disease or approximately 700 days post-inoculation. Tissues were divided and homogenized or fixed in 10% buffered neutral formalin. Immunohistochemistry, enzyme immunoassay, and western blot were used to detect misfolded prion protein (PrPSc) in tissue.
Results: Humanized transgenic mice inoculated with the raccoon passaged CWD agent from white-tailed deer exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPScwas detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPScalso was detected in brain tissue by western blot and immunohistochemistry. No PrPScwas detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from white-tailed deer did not have detectable PrPScusing conventional immunoassay techniques.
Conclusions: The host range of the CWD agent from white-tailed deer was expanded in our experimental model after one passage through raccoons.
Funded by: This research was funded in its entirety by congressionally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Acknowledgement: We thank Quazetta Brown, Lexi Frese, Rylie Frese, Kevin Hassall, Leisa Mandell, and Trudy Tatum for providing excellent technical support to this project.
Stable and highly zoonotic cervid prion strain is possible
Manuel Camacho, Xu Qi, Liuting Qing, Sydney Smith, Jieji Hu, Wanyun Tao, Ignazio Cali, and Qingzhong Kong Department of Pathology, Case Western Reserve University, Cleveland, USA
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in some areas. Multiple in vitro conversion experiments and in vivo animal studies suggest that the CWD-to-human transmission barrier is not unbreakable. A major public health concern on CWD zoonosis is the emergence of highly zoonotic CWD strains. We aim to address the question of whether highly zoonotic CWD strains are possible.
Material and Methods: We inoculated a few sCJD brain samples into cervidized transgenic mice, which were intended as negative controls for bioassays of brain tissues from sCJD cases who had hunted or consumed vension from CWD-endemic states. Some of these mice became infected and their brain tissues were further examined by serial passages in humanized or cervidized mice.
Results: Passage of sCJDMM1 in transgenic mice expressing elk PrP (Tg12) resulted in a ‘cervidized’ CJD strain that we termed CJDElkPrP. We observed 100% transmission of CJDElkPrPin transgenic mice expressing human PrP (Tg40h). We passaged CJDElkPrPtwo more times in the Tg12 mice. We found that such second and third passage CJDElkPrPprions also led to 100% infection in the Tg40h mice. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice, despite that natural elk CWD isolates and CJDElkPrPshare the same elk PrP sequence.
Conclusions: Our data demonstrate that highly zoonotic cervid prion strains are not only possible but also can be stably maintained in cervids and that CWD zoonosis is prion strain-dependent.
Funded by: NIH
Grant number: R01NS052319, R01NS088604, R01NS109532
Acknowledgement: We want to thank the National Prion Disease Pathology Surveillance Center and Drs. Allen Jenny and Katherine O’Rourke for providing the sCJD samples and the CWD samples, respectively.
Adaptation of chronic wasting disease (CWD) prion strains in hosts with different PRNP genotypes
Camilo Duque Velasqueza,c, Elizabeth Triscotta,c, Chiye Kima,c, Diana Morenoa,c, Judd Aikenb,c, and Debbie McKenziea,c
aDepartment of Biological Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; bDepartment of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; cCentre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
Aims: The contagious nature of CWD epizootics and the PrPCamino acid variation of cervids (and susceptible sympatric species) guarantee the expansion of prion conformational diversity and selective landscapes where new strains can arise. CWD strains can have novel transmission properties including altered host range that may increase zoonotic risk as circulating strains diversify and evolve. We are characterizing the host adaptability of characterized CWD strains as well as CWD isolates from different cervid species in various enzootic regions.
Material and Methods: Characterized CWD strains as well as a number of isolates from hunter-harvested deer were bioassayed in our rodent panel (transgenic mice expressing cervid alleles G96, S96 and H95-PrPC, elk PrPC, bovine PrPC, and both hamsters and non-transgenic laboratory mice). Strain characteristics were compared using computer based scoring of brain pathology (e.g. PrPCWDbrain distribution), western blot and protein misfolding cyclic amplification (PMCA).
Results: Transmission of various isolates resulted in the selection of strain mixtures in hosts expressing similar PrPC, particularly for polymorphic white-tailed deer and for Norwegian reindeer. As of the second passage, transmission of P153 moose prions from Norway has not resulted in emergence of strains with properties similar to any North American CWD strains in our taxonomic collection (Wisc-1, CWD2, H95+and 116AG).
Conclusions: Our data indicates polymorphic white-tailed deer can favor infection with more than one strain. Similar to transmission studies of Colorado CWD isolates from cervids expressing a single PrPCprimary structure, the isolate from Norway reindeer (V214) represents a strain mixture, suggesting intrinsic strain diversity in the Nordfjella epizootic. The diversity of CWD strains with distinct transmission characteristics represents a threat to wildlife, sympatric domestic animals and public health.
Funded by: Genome Canada and Genome Alberta (Alberta Prion Research Institute and Alberta Agriculture & Forestry); NSERC Grant number: #LSARP 10205; NSERC RGPIN-2017-05539
Acknowledgement: We would like to thank Margo Pybus (Alberta Environment and Parks) Trent Bollinger (University of Saskatchewan) for providing us with tissue samples from hunter-harvested deer and Sylvie Benestad for providing moose and reindeer samples.
Application of PMCA to understand CWD prion strains, species barrier and zoonotic potential
Sandra Pritzkowa, Damian Gorskia, Frank Ramireza, Fei Wanga, Glenn C. Tellingb, Justin J. Greenleec, Sylvie L. Benestadd, and Claudio Sotoa aDepartment of Neurology, University of Texas Medical School at Houston, Houston, Texas, USA; bDepartment of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA; cVirus and Prion Research Unit, United States Department of Agriculture, Ames, Iowa, USA; dNorwegian Veterinary Institute, OIE Reference Laboratory for CWD, Ås, Norway
Aims: Chronic wasting disease (CWD) is a prion disease affecting various species of cervids that continues to spread uncontrollably across North America and has recently been detected in Scandinavia (Norway, Sweden and Finland). The mechanisms responsible for the natural transmission of CWD are largely unknown. Furthermore, the risk of CWD transmission to other species, including humans, is also unknown and remains a dangerous enigma. In this study, we investigated the potential of CWD prions to infect several other animal species (sheep, cattle, pig, hamster, and mouse) including humans, by examining their capacity to convert the normal prion protein of distinct species in a PMCA reaction. Moreover, we also investigated whether the in vivo passage of CWD through intermediate species alters their capacity for zoonotic transmission, which may represent a major hazard to human health.
Material and Methods: For these studies, we used brain material from CWD-infected white-tailed deer (Odocoileus virginianus), elk (Cervus canadensis), and mule deer (Odocoileus hemionus) as species native to North America. We also used CWD-infected Moose (Alces alces), reindeer (Rangifer tarandus) and red deer (Cervus elaphus) as Norwegian cervids. We also used brains from cattle, sheep and pigs experimentally infected by CWD. To study interspecies-transmission and zoonotic potential, samples were tested via PMCA for the conversion of PrPCinto PrPScusing different combinations of inoculum and host species. Based on these analyses we estimated the spillover and zoonotic potential for different CWD isolates. We define and quantify spillover and zoonotic potential indices as the efficiency by which CWD prions sustain prion generation in vitro at the expense of normal prion proteins from various mammals and human, respectively.
Results: Our results show that prions from some cervid species, especially those found in Northern Europe, have a higher potential to transmit disease characteristics to other animals. Conversely, CWD-infected cervids originated in North America appear to have a greater potential to generate human PrPSc. We also found that in vivo transmission of CWD to cattle, but not to sheep or pigs substantially increases the ability of these prions to convert human PrPCby PMCA.
Conclusions: Our findings support the existence of different CWD prion strains with distinct spillover and zoonotic potentials. We also conclude that transmission of CWD to other animal species may increase the risk for CWD transmission to humans. Our studies may provide a tool to predict the array of animal species that a given CWD prion could affect and may contribute to understanding the risk of CWD for human health.
Funded by: National Institute of Health Grant number: P01 AI077774
Generation of human chronic wasting disease in transgenic mice
Zerui Wanga, Kefeng Qinb, Manuel V. Camachoa, Ignazio Cali a,c, Jue Yuana, Pingping Shena, Tricia Gillilanda, Syed Zahid Ali Shaha, Maria Gerasimenkoa, Michelle Tanga, Sarada Rajamanickama, Anika Yadatia, Lawrence B. Schonbergerd, Justin Greenleee, Qingzhong Konga,c, James A. Mastriannib, and Wen-Quan Zoua,c
aDepartment of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, USA; bDepartment of Neurology and Center for Comprehensive Care and Research on Memory Disorders, the University of Chicago Pritzker School of Medicine, Chicago, USA; cNational Prion Disease Pathology Surveillance Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; dDivision of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA, USA; eVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA, USA
Aims: Chronic wasting disease (CWD) results from the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC) in the brains of deer and elk. It has been spreading rapidly throughout many regions of North America, exported inadvertently to South Korea, and more recently identified in Europe. Mad cow disease has caused variant Creutzfeldt-Jakob disease (vCJD) in humans and is currently the only known zoonotic prion disease. Whether CWD is transmissible to humans remains uncertain. The aims of our study were not only to confirm whether CWD prion isolates can convert human brain PrPCinto PrPScin vitro by serial protein misfolding cyclic amplification (sPMCA) but also to determine whether the sPMCA-induced CWD-derived human PrPScis infectious.
Material and Methods: Eight CWD prion isolates from 7 elks and 1 deer were used as the seeds while normal human brain homogenates containing either PrP-129 MM (n = 2) or PrP-129 VV (n = 1) were used as the substrates for sPMCA assay. A normal elk brain tissue sample was used as a negative control seed. Two lines of humanized transgenic (Tg) mice expressing either human PrP-129VV or −129 MM polymorphism were included for transmission studies to determine the infectivity of PMCA-amplified PrPSc. Wester blotting and immunohistochemistry and hematoxylin & eosin staining were used for determining PrPScand neuropathological changes of inoculated animals.
Results: We report here the generation of the first CWD-derived infectious human PrPScusing elk CWD PrPScto initiate conversion of human PrPCfrom normal human brain homogenates with PMCA in vitro. Western blotting with a human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPScwas derived from the human brain PrPCsubstrate. Two lines of humanized transgenic mice expressing human PrPCwith either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPScpatterns and neuropathological changes in the brain.
Conclusions: Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSchas the potential to overcome the species barrier and directly convert human PrPCinto infectious PrPScthat can produce bona fide prion disease when inoculated into humanized transgenic mice.
Funded by: CJD Foundation and NIH
Mortality surveillance of persons potentially exposed to chronic wasting disease
R.A. Maddoxa, R.F. Klosb, L.R. Willb, S.N. Gibbons-Burgenerb, A. Mvilongoa, J.Y. Abramsa, B.S. Applebyc, L.B. Schonbergera, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bWisconsin Department of Health Services (WDHS), Division of Public Health, Madison, USA; cNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: It is unknown whether chronic wasting disease (CWD), a prion disease of cervids, can infect people, but consumption of meat from infected animals would be the most likely route of transmission. Wisconsin Department of Health Services, Division of Public Health (WDHS) personnel maintain a database consisting of information collected from hunters who reported eating, or an intention to eat, venison from CWD-positive cervids. These data, collected since 2003, allow for the evaluation of causes of mortality in individuals potentially exposed to CWD.
Material and Methods: The WDHS database contains the name, date of birth, when available, year of CWD-positive deer harvest, and city and state of residence for each potentially exposed individual. The database also includes information on how the deer was processed (self-processed or by a commercial operator) and when applicable, names of others with whom the venison was shared. Duplicate entries (i.e., those who consumed venison from CWD-positive deer in multiple hunt years) are determined by first name, last name, and date of birth. All names in the database are cross-checked with reported cases of human prion disease in Wisconsin and cases in the National Prion Disease Pathology Surveillance Center (NPDPSC) diagnostic testing database. Persons with date of birth available are also cross-checked with prion disease decedents identified through restricted-use national multiple cause-of-death data via a data use agreement with the National Center for Health Statistics (NCHS).
Results: The database currently consists of 1561 records for hunt years 2003–2017 and 87 additional records for 2018–2019. Of these, 657 records have accompanying date of birth; 15 entries were removed as duplicates leaving 642 unique individuals. Of these individuals, 278 of 426 (66%) who ate venison from a CWD-positive deer and provided processing information reported self-processing. No matches were found among any persons in the database cross-checked with WDHS human prion disease surveillance data, NPDPSC data (February 2022 update), and NCHS data through 2020.
Conclusions: Because of the linkage of person and CWD-positive animal in the WDHS database, reviewing the cause of mortality in potentially exposed persons is possible. The number of individuals cross-checked so far is likely only a small percentage of those potentially exposed to CWD in Wisconsin, and many more years of vital status tracking are needed given an expected long incubation period should transmission to humans occur. Nevertheless, the findings of this ongoing review are thus far reassuring.
Prion disease incidence, United States, 2003–2020
R.A. Maddoxa, M.K. Persona, K. Kotobellib, A. Mvilongoa, B.S. Applebyb, L.B. Schonbergera, T.A. Hammetta, J.Y. Abramsa, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: Mortality data, in conjunction with neuropathological and genetic testing results, are used to estimate prion disease incidence in the United States.
Material and Methods: Prion disease decedents for 2003–2020 were identified from restricted-use U.S. national multiple cause-of-death data, via a data use agreement with the National Center for Health Statistics, and from the National Prion Disease Pathology Surveillance Center (NPDPSC) database. NPDPSC decedents with neuropathological or genetic test results positive for prion disease for whom no likely match was found in the NCHS multiple cause-of-death data were added as cases for incidence calculations, while those with negative neuropathology results but with cause-of-death data indicating prion disease were removed. Unmatched cases in the NPDPSC database lacking neuropathological testing but with a positive real-time quaking-induced conversion (RT-QuIC) test result were additionally assessed. Age-specific and age-adjusted average annual incidence rates were calculated from the combined data; the year 2000 as the standard population and the direct method were used for age-adjustment.
Results: A total of 7,921 decedents were identified as having prion disease during 2003–2020 for an age-adjusted average annual incidence of 1.2 per million population. The age-adjusted incidence between males and females (1.3 and 1.1 per million, respectively) differed significantly (p < 0.0001). The age-specific average annual incidence among those <55 and ≥55 years of age was 0.2 and 4.8 per million, respectively; incidence among those ≥65 was 6.1 per million. Eighteen cases were <30 years of age for an age-specific incidence of 8.0 per billion; only 6 of these very young cases were sporadic (3 sporadic CJD, 3 sporadic fatal insomnia), with the rest being familial (9), variant (2), or iatrogenic (1). The age-adjusted annual incidence for the most recent year of data, 2020, was 1.3 per million. However, assessment of RT-QuIC positive cases lacking neuropathology in the NPDPSC database suggested that approximately 20% more cases may have occurred in that year; the addition of a subset of these cases that had date of death information available (n = 44) increased the 2020 rate to 1.4 per million.
Conclusions: Mortality data supplemented with the results of neuropathological, CSF RT-QuIC, and genetic testing can be used to estimate prion disease incidence. However, the identification in the NPDPSC database of RT-QuIC-positive cases lacking date of death information suggests that this strategy may exclude a number of probable prion disease cases. Prion disease cases <30 years of age, especially those lacking a pathogenic mutation, continue to be very rare.
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
ATYPRION project: assessing the zoonotic potential of interspecies transmission of CWD isolates to livestock (preliminary results).
Enric Vidala,b, Juan Carlos Espinosac, Samanta Gilera,b, Montserrat Ordóñeza,b, Guillermo Canteroa,b, Vincent Béringued, Justin J. Greenleee, and Juan Maria Torresc
aUnitat mixta d’Investigació IRTA-UAB en Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; bIRTA. Programa de Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; cCentro de Investigación en Sanidad Animal, CISA-INIA-CSIC, Valdeolmos, Madrid, Spain; dMolecular Virology and Immunology, French National Research Institute for Agriculture, Food and Environment (INRAE), Université Paris-Saclay, Jouy-en-Josas, France; eVirus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, USA
Aims: Since variant Creutzfeldt-Jackob disease was linked to the consumption of bovine spongiform encephalopathy prions, the study of the pathobiological features of animal prions, particularly their zoonotic potential, is of great concern to the scientific community and public health authorities. Furthermore, interspecies transmission of prions has been demonstrated as a putative evolutionary mechanism for prions, that can lead to the emergence of new features including the ability to infect humans. For instance, small ruminants’ atypical scrapie prions, when propagated in a bovine or porcine host, can shift to a classical BSE phenotype thus posing a potential risk in case of human exposure. So far, no hard evidence of zoonotic transmission of cervids’ chronic wasting disease (CWD) to humans has been published, however experimental transmission to bovine, ovine and caprine hosts has been achieved. Our goal is to investigate if, once passaged through these domestic species, CWD prions might become infectious to humans.
Material and Methods: Different CWD isolates experimentally adapted to cattle, sheep and goat (Hamir et al, 2005, 2006, 2007, Greenlee et al 2012) have been intracerebrally inoculated to transgenic mouse models expressing the human cellular prion protein either homozygous for methionine or valine at codon 129 (Tg340-Met129 and Tg362-Val129). Additionally, inocula obtained from experimental transmission of elk CWD to ovinized (Tg501) and bovinized (BoTg110) transgenic mice, as well as white-tailed deer CWD to BoTg110 mice, are currently being bioassayed in both human PrPCtransgenic models.
Results and conclusions: No evidence of transmission has been found on first passage for bovine adapted elk and mule deer CWD to none of the humanized models. The remaining bioassays are ongoing without showing clinical signs yet, as well as second passages for the negative 1stpassages.
Funded by: La Marató de TV3 foundation. Grant number: ATYPRION (201,821–30-31-32)
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Prion Conference 2018 Abstracts
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.
Methods
Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).
Results
Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).
Conclusions
While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.
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P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2)
(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.
Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.
We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.
Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.
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P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission
Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.
Methods
We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.
Results
We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.
Conclusions
PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.
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P180 Clinico-pathological analysis of human prion diseases in a brain bank series
Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)
(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.
Background and objective:
The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.
Methods:
We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.
Results:
176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.
Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.
Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.
Discussion:
A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:
www.clinicbiobanc.org/banc-teixits-neurologics/mostres/en_index.html
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P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures
Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)
(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.
Aims:
Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.
Methods:
Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.
Results:
The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.
Conclusions:
Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.
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WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)
(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
See also poster P103
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
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WA16 Monitoring Potential CWD Transmission to Humans
Belay ED
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.
The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.
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P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan
Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)
(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.
Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.
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Source Prion Conference 2018 Abstracts
www.ncbi.nlm.nih.gov/pmc/articles/PMC6738495/
transmissiblespongiformencephalopathy.blogspot.com/2018/05/prion-2018-may-22-25-2018-santiago-de.html
chronic-wasting-disease.blogspot.com/2018/07/oral-transmission-of-cwd-into.html
prionconference.blogspot.com/2018/
Volume 24, Number 8—August 2018 Research Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions
Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)
Abstract Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted.
snip...
Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).
A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.
The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.
In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).
The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.
Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.
Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.
This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.
Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.
wwwnc.cdc.gov/eid/article/24/8/16-1888_article
www.ed.ac.uk/clinical-brain-sciences/news/news-jul-dec-2018/cwd-prions-human-conversion
Prion 2017 Conference Abstracts
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen
This is a progress report of a project which started in 2009.
21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves.
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice.
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation.
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS ABSTRACTS REFERENCE
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
SATURDAY, FEBRUARY 23, 2019
Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019
chronic-wasting-disease.blogspot.com/2019/02/chronic-wasting-disease-cwd-tse-prion.html
TUESDAY, NOVEMBER 04, 2014
Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011 Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "
chronic-wasting-disease.blogspot.com/2014/11/six-year-follow-up-of-point-source.html
Transmission Studies Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
snip....
web.archive.org/web/20090506002237/http://www..bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿
Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.
jvi.asm.org/content/83/18/9608.full
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.
science.sciencemag.org/content/311/5764/1117..long
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE. see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”
From: TSS Subject: CWD aka MAD DEER/ELK TO HUMANS
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam, In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091).
Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message----- From:
Sent: Sunday, September 29, 2002 10:15 AM To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip... *** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
snip... full text ;
chronic-wasting-disease.blogspot.com/2008/04/prion-disease-of-cervids-chronic.html
> However, to date, no CWD infections have been reported in people.
sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven. if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;
sporadic = 54,983 hits
www.ncbi.nlm.nih.gov/pubmed/?term=sporadic
spontaneous = 325,650 hits
www.ncbi.nlm.nih.gov/pubmed/?term=spontaneous
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD.
SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys
www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true
wwwnc.cdc.gov/eid/article/20/1/13-0858_article
CWD TSE PRION AND ZOONOTIC, ZOONOSIS, POTENTIAL
Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY
Date: Fri, 18 Oct 2002 23:12:22 +0100
From: Steve Dealler
Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member
To: BSE-L@ References:
Dear Terry,
An excellent piece of review as this literature is desperately difficult to get back from Government sites.
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
Steve Dealler ===============
caninespongiformencephalopathy.blogspot.com/2010/03/canine-spongiform-encephalopathy-aka.html
''The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).''
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).
The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (...TSS)
snip...see full report ;
web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf
web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf
Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk
BSE Inquiry Steve Dealler
Management In Confidence
BSE: Private Submission of Bovine Brain Dealler
snip...see full text;
MONDAY, FEBRUARY 25, 2019
***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
bseinquiry.blogspot.com/2019/02/mad-dogs-and-englishmen-bse-scrapie-cwd.html
terry
Chronic Wasting Disease Detected in Additional Breeding Facilities in Frio and Zavala Counties
July 13, 2023
Media Contact: TPWD News, Business Hours, 512-389-8030 News Image Share on Facebook Share Release URL
AUSTIN — Texas Parks and Wildlife Department (TPWD) received notification of two new cases of Chronic Wasting Disease (CWD) in deer-breeding facilities in Frio and Zavala Counties.
In Frio County, a 2-year-old white-tailed doe died in a deer-breeding facility and was post-mortem tested following CWD surveillance testing requirements. This is the second deer-breeding facility in Frio County to have a positive CWD detection.
In Zavala County, a 3-year-old white-tailed buck died in a deer-breeding facility and was post-mortem tested following CWD surveillance testing requirements. This is the second deer-breeding facility in Zavala County to have a positive CWD detection.
Texas A&M Veterinary Medical Diagnostic Laboratory in College Station initially analyzed postmortem samples; the National Veterinary Services Laboratory in Ames, Iowa, provided a CWD-positive confirmation for both samples.
During the upcoming August meeting of the Texas Parks and Wildlife Commission, TPWD staff will propose the development of CWD surveillance zones within the general vicinity of both CWD-positive facilities. If the proposal passes, the zones will include mandatory sampling of hunter harvested deer, as well as carcass movement and disposal requirements to take effect during the upcoming deer season.
CWD has an incubation period that can span years, meaning the first indication in a herd may likely come through surveillance testing rather than observed clinical signs. Early detection and proactive monitoring improve the state’s response time to a disease outbreak and can greatly reduce the risk of further disease spread.
CWD is a fatal neurological disease found in certain cervids including deer, elk, moose and other members of the deer family. This slow, progressive disease may not produce visible signs in susceptible species for several years after infection. As the disease progresses, animals with CWD may show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears, and excessive thirst, salivation or urination.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border. CWD has since been detected in Texas captive and free-ranging cervids, including white-tailed deer, mule deer, red deer and elk. For more information on previous detections in Texas and CWD best management practices for hunters and landowners, visit TPWD’s CWD page.
tpwd.texas.gov/newsmedia/releases/?req=20230713a
Texas Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
For Immediate Release
April 11, 2023
Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
AUSTIN, TX – Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of two new cases of Chronic Wasting Disease (CWD) in separate deer breeding facilities in Hamilton and Frio counties. These cases mark the first detection of the disease in each county.
A single case in a Hamilton County facility was detected using antemortem (live animal) testing conducted to determine if the animal was movement qualified to transfer from the property to a registered release site. A single case in a Frio County facility was detected using postmortem testing following a natural mortality conducted to meet TPWD surveillance requirements.
The samples submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory in College Station were ultimately sent to the National Veterinary Services Laboratory (NVSL) in Ames, Iowa, where the presence of CWD was confirmed in all samples. Officials took immediate action to secure all deer at the facilities. TPWD and TAHC plan to continue working together to conduct additional investigations into the extent of the disease within the facilities.
With an incubation period that can span years, the first indication of CWD in a herd may likely come through testing, rather than observing clinical signs. Early detection and proactive monitoring improve the state’s response time to a disease outbreak and can greatly reduce the risk of further disease spread. Antemortem testing provides a continuous testing baseline that can further clarify the epidemiological uncertainties related to the origin of a disease outbreak. In addition to postmortem testing and other surveillance requirements, this testing helps guide future changes to the disease management strategy.
CWD is a fatal neurological disease found in certain cervids including deer, elk, moose and other members of the deer family. CWD is a slow and progressive disease. Due to a long incubation, cervids infected with CWD may not produce any visible signs for several years after becoming infected. As the disease progresses, animals with CWD show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, excessive thirst, salivation or urination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border. CWD has since been detected in captive and free-ranging cervids in the state including, white-tailed deer, mule deer, red deer and elk. For more information on previous detections in Texas, visit TPWD’s CWD page.
To date there are no known cases where CWD has infected a human; however, recent research suggests that CWD transmission from infected animals to humans should not be ruled out. As a precaution, it is recommended that hunters test harvested cervid species for CWD, and not consume the meat of infected animals.
For more information about CWD, visit the TPWD website or the TAHC website.
### The Texas Animal Health Commission (TAHC) was established in 1893 as the Livestock Sanitary Commission and charged with protecting the state’s domestic animals “from all contagious or infectious diseases of a malignant character.” TAHC remains true to this charge while evolving with the times to protect the health and marketability of all Texas livestock and poultry. Learn more about the TAHC visit www.tahc.texas.gov.
www.tahc.texas.gov/news/2023/2023-04-11_CWD_FrioHamilton.pdf
Texas CWD seven new cases three separate deer-breeding facilities in Zavala, Washington and Gonzales counties 471 confirmed to date
Chronic Wasting Disease Discovered in Deer-Breeding Facilities in Zavala, Washington and Gonzales Counties
March 21, 2023
Media Contact: TPWD News, Business Hours, 512-389-8030 News
Additional Case Detected at High-Fence Release Site in Hunt County
AUSTIN – The Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of seven new cases of chronic wasting disease (CWD) in three separate deer-breeding facilities in Zavala, Washington and Gonzales counties. These cases mark the first detection of the disease in each county.
Three cases in a Zavala County facility and one case in a Washington County facility were detected through antemortem (live animal) testing conducted prior to their transfer from the properties to registered release sites. Three cases in a Gonzales County facility were detected by antemortem and postmortem testing, as required by a CWD Herd Plan established after the facility received CWD-exposed deer from an Uvalde County deer breeding facility in which CWD was detected in 2021.
The samples were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory in College Station and were ultimately sent to the National Veterinary Services Laboratory in Ames, Iowa, where the presence of CWD was confirmed in all seven samples. Officials have taken immediate action to secure all deer at the facilities; TPWD and TAHC plan to continue working together to conduct additional investigations looking into the extent of the disease within the facilities.
“It continues to be imperative for producers to stay diligent with testing susceptible species for CWD,” said Dr. Andy Schwartz, TAHC executive director and state veterinarian. “With an incubation period that can span years, the first indication of this degenerative disease in a herd may likely come through testing, rather than observing clinical signs. Early detection and proactive monitoring improve the state’s response time and can greatly reduce the risk of further disease spread.”
Since November 2021, when the Texas Parks and Wildlife Commission adopted a requirement to antemortem test deer for CWD prior to liberation, this disease surveillance tool has detected CWD in five deer breeding facilities where it was not previously known to exist. Transferring even one CWD-infected deer from a breeding facility could ultimately affect all deer in the vicinity of the transfer, with irreversible impacts.
“With disease surveillance, our goal is to monitor and identify disease expeditiously to minimize the impact of outbreaks,” said Dr. Hunter Reed, TPWD wildlife veterinarian. “This is a continuous process that hopefully results in little to no disease being detected since [ideally] our disease management strategies are effective in limiting transmission. This additional surveillance from antemortem testing not only allows us to respond more quickly to an outbreak, but it also provides us with a robust, continuous testing baseline that can further elucidate the epidemiological uncertainties related to the origin of the disease outbreak, in addition to guiding future changes to our disease management strategy.”
In Hunt County, TPWD and TAHC received confirmation of CWD in a white-tailed doe harvested on a release site located adjacent to a breeding facility already known to have CWD. This is the first positive detection in a free-range deer in the county.
First recognized in the U.S. in 1967, CWD has since been documented in captive and/or free-ranging deer in 30 states and three Canadian provinces.
In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the Texas-New Mexico border and has since been detected in 471 captive or free-ranging cervids — including white-tailed deer, mule deer, red deer and elk — in 20 Texas counties. For more information on previous detections, visit TPWD’s CWD page.
CWD is a fatal neurological disease found in certain cervids, including deer, elk, moose and other members of the deer family. CWD is a slow and progressive disease. Due to a long incubation, cervids infected with CWD may not produce any visible signs for several years after becoming infected. As the disease progresses, animals with CWD show changes in behavior and appearance. Clinical signs may include progressive weight loss, stumbling or tremors with a lack of coordination, excessive thirst, salivation or urination, loss of appetite, teeth grinding, abnormal head posture and/or drooping ears.
To date there are no known cases where CWD has infected a human; however, recent research suggests that CWD transmission from infected animals to humans should not be ruled out. Consequently, as a precaution, it is recommended that hunters test harvested cervid species for CWD, and that no one consumes the meat of infected animals.
For more information about CWD, visit the TPWD website or the TAHC website.
tpwd.texas.gov/newsmedia/releases/?req=20230321b
“A total of 505 cervids (including white-tailed deer, mule deer and elk) have tested positive for CWD in Texas. Free-ranging deer have accounted for 101 of those cases while 404 are associated with a breeding facility or breeder release site.”
Texans spend $4.3 billion annually hunting white-tailed deer, Texas A&M study shows
TEXAS SPORTS NATION
GENERAL
Texans spend $4.3 billion annually hunting white-tailed deer, Texas A&M study shows
Matt Wyatt Staff writer May 26, 2023
Deer hunters and landowners participating in Texas' hugely popular Managed Lands Deer Program, which offers a longer deer season and other liberalized deer hunting rules, will begin paying a modest annual fee for the voluntary program under a law recently adopted by the Texas Legislature. Shannon Tompkins/Houston Chronicle
Few states, if any, can claim a closer connection to white-tailed deer hunting than Texas.
snip...
“One of the things that there was an interest in was better understanding the overall value, or economic importance of whitetail deer within the context of various other ongoing challenges or issues, including chronic wasting disease,” Lopez said.
“There was an interest in trying to better understand the potential economic implications of a challenging issue like chronic wasting disease to this very specific industry.”
A total of 505 cervids (including white-tailed deer, mule deer and elk) have tested positive for CWD in Texas. Free-ranging deer have accounted for 101 of those cases while 404 are associated with a breeding facility or breeder release site.
There is currently no cure for CWD, and it is considered impossible to eradicate once it becomes established.
As this disease continues to creep across the Texas landscape, it could eventually have negative impacts on white-tailed deer populations.
A decline in white-tailed deer numbers could cut into the $4.3 billion spent every year on hunting, spelling disaster for the local economies and communities that depend on that money and the other wildlife species that benefit from it.
www.houstonchronicle.com/texas-sports-nation/general/article/texas-whitetail-deer-hunting-spending-18121324.php
ECONOMIC VALUES OF WHITE-TAILED DEER IN TEXAS
2022 SURVEY: PART I
nri.tamu.edu/media/3702/economic-values-of-white-tailed-deer-in-texas-2022-survey-part-i.pdf
Chronic Wasting Disease (CWD):
2021 Incident
7 Positive Facilities
3 Facilities in Uvalde, 1 in Duval, 1 in Hunt, 1 in Matagorda, & 1 in Mason
1 release site in Hunt co. associated with a positive 2021 facility - NVSL confirmed March 17, 2023.
302 Trace Herds: 177 Breeder Facilities, 116 Release Sites, 4 Nursing Facilities, 5 DMP Sites
Status
Released after meeting requirements: 165 Breeder Facilities, 59 Release Sites/DMPs /Nursing Facilities
Under a Herd Plan: 5 Breeder Facilities (includes positive facilities), 25 Release Sites/DMP
Pending a signed herd plan: 7 Breeder Facilities (includes positive facilities), 41 Release Sites/DMP
Out of State - 8 Facilities
2022 Incident - 84 total involved herds
2 Positive Facilities
Gillespie County – Confirmed August 30, 2022
Limestone County – Confirmed September 13, 2022
82 Trace Facilities
22 Breeder Facilities
59 Release Sites
1 DMP Site
Status
Released after meeting requirements: 10 Breeder Facilities, 5 Release Sites
Signed Herd Plan – 14 Release Sites
Pending Signed Herd Plan: 14 Breeder Facilities (includes positive facilities), 41 Release Sites/DMP
Summary Minutes of the 415th Commission Meeting – 4/04/2023
4
2023 Incident - 44 total affected herds
4 Positive Facilities
Zavala County – confirmed March 10, 2023
Washington County – confirmed March 7, 2023
Gonzales County – confirmed March 17, 2023
Hamilton County – confirmed March 21, 2023
40 Trace Facilities: 10 Breeder Facilities, 28 Release Sites, 1 DMP Site, 1 Nursing Facility
Status
Released after meeting requirements – 1 Breeder Facility
Under a Herd Plan- None at this time: Unconfirmed Frio County Facility- suspect positive notification received March 17, 2023
1 Positive Facility
17 Trace Facilities: 2 Breeder Facilities, 13 Release Sites, 2 DMP Sites
Released after meeting requirements – 2 Breeder Facilities
USDA VS review of the Texas CWD HCP
TAHC is working with TPWD to modify the TWIMS database to better support the HCP
Review of all enrolled herds has begun, and is to be completed by the end of February 2023
Update: USDA extended the deadline. Reviews have been completed in four of the six regions, with good progress being made in the remaining two regions.
www.tahc.texas.gov/agency/meetings/SummaryMinutesCommissionMeeting415.pdf
“Regarding the current situation involving CWD in permitted deer breeding facilities, TPWD records indicate that within the last five years, the seven CWD-positive facilities transferred a total of 2,530 deer to 270 locations in 102 counties and eight locations in Mexico (the destinations included 139 deer breeding facilities, 118 release sites, five Deer Management Permit sites, and three nursing facilities).'' ...
It is apparent that prior to the recent emergency rules, the CWD detection rules were ineffective at detecting CWD earlier in the deer breeding facilities where it was eventually discovered and had been present for some time; this creates additional concern regarding adequate mitigation of the risk of transferring CWD-positive breeder deer to release sites where released breeder deer come into contact with free-ranging deer...
Commission Agenda Item No. 5 Exhibit B
DISEASE DETECTION AND RESPONSE RULES
PROPOSAL PREAMBLE
1. Introduction.
snip...
A third issue is the accuracy of mortality reporting. Department records indicate that for each of the last five years an average of 26 deer breeders have reported a shared total of 159 escapes. Department records for the same time period indicate an average of 31 breeding facilities reported a shared total of 825 missing deer (deer that department records indicate should be present in the facility, but cannot be located or verified).
tpwd.texas.gov/business/feedback/meetings/2022/1104/agenda/item.phtml?item=5
Commission
September 22, 2020
Chronic Wasting Disease (CWD):
A new CWD positive breeding herd was disclosed in February 2020 in Kimble County. This herd depopulation was completed in July 2020. Including the two index positive deer, an additional eight more positive deer were disclosed (approximate herd prevalence 12%). Since July 2015 and prior to this discovery, five positive captive breeder herds have been disclosed and four of those are in Medina County. One herd in Lavaca and three herds in Medina County were depopulated leaving one large herd in Medina County that is managed on a herd plan. A new zone was established in Val Verde County in December 2019 as a result of a positive free-ranging White-tailed Deer (WTD). A second positive WTD was also disclosed in February 2020 in the same area.
SUMMARY MINUTES OF THE 407th COMMISSION MEETING – 9/22/2020
Scrapie: The flock identified in April 2016 remains under quarantine in Hartley County.
SUMMARY MINUTES OF THE 407th COMMISSION MEETING – 9/22/2020
Texas CWD Herd Kimble County Has approximate prevalence 12% to date
web.archive.org/web/20201020110225/https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22.pdf
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas. Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
CWD poses a significant threat to the future of hunting in Texas. Deer population declines of 45 and 50 percent have been documented in Colorado and Wyoming. A broad infection of Texas deer populations resulting in similar population impacts would inflict severe economic damage to rural communities and could negatively impact land markets. Specifically, those landowners seeking to establish a thriving herd of deer could avoid buying in areas with confirmed CWD infections. As they do with anthrax-susceptible properties, land brokers may find it advisable to inquire about the status of CWD infections on properties that they present for sale. Prospective buyers should also investigate the status of the wildlife on prospective properties. In addition, existing landowners should monitor developments as TPWD crafts management strategies to identify and contain this deadly disease.
Dr. Gilliland (c-gilliland@tamu.edu) is a research economist with the Texas Real Estate Research Center at Texas A&M University.
www.recenter.tamu.edu/articles/tierra-grande/oh-deer-2314
Texas CWD Surveillance Positives
tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD
Counties where CWD Exposed Deer were Released
tpwd.texas.gov/documents/257/CWD-Trace-OutReleaseSites.pdf
Number of CWD Exposed Deer Released by County
tpwd.texas.gov/documents/258/CWD-Trace-OutReleaseSites-NbrDeer.pdf
Chronic Wasting Disease CWD Captive Herds updated April 2023
www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/cervid/cervids-cwd/cervids-voluntary-hcp
Chronic Wasting Disease CWD Captive Herds updated April 2023
www.aphis.usda.gov/animal_health/animal_diseases/cwd/downloads/status-of-captive-herds.pdf
Listing of CWD Cases in Texas
tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD
“Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.”
PART 2. TPWD CHAPTER 65. DIVISION 1. CWD
31 TAC §§65.82, 65.85, 65.88
The Texas Parks and Wildlife Commission in a duly noticed meeting on May 25, 2023 adopted amendments to 31 TAC §§65.82, 65.85, and §65.88, concerning Disease Detection and Response, without changes to the proposed text as published in the April 21, 2023, issue of the Texas Register (48 TexReg 2048). The rules will not be republished.
Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.
www.sos.texas.gov/texreg/archive/June302023/Adopted%20Rules/31.NATURAL%20RESOURCES%20AND%20CONSERVATION.html#57
TEXAS CWD STRAIN
“Wow,” he said. “Unlike anything we've seen before.”
The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.
TEXAS CWD STRAIN
77. Assessing chronic wasting disease strain differences in free-ranging cervids across the United States
Kaitlyn M. Wagnera, Caitlin Ott-Connb, Kelly Strakab, Bob Dittmarc, Jasmine Battend, Robyn Piercea, Mercedes Hennessya, Elizabeth Gordona, Brett Israela, Jenn Ballarde and Mark D Zabela
aPrion Research Center at Colorado State University; bMichigan Department of Natural Resources; cTexas Parks and Wildlife Department; dMissouri Department of Conservation, 5. Arkansas Game and Fish Commission CONTACT Kaitlyn M. Wagner miedkait@rams.colostate.edu
ABSTRACT
Background/Introduction: Chronic wasting disease (CWD) is an invariably fatal prion disease affecting captive and free-ranging cervids, including white-tailed deer, mule deer, moose, elk, and reindeer. Since the initial description of the disease in the 1960’s, CWD has spread to 23 states, 3 Canadian Provinces, South Korea, Norway and, most recently, Finland. While some outbreaks of CWD were caused by transport of infected animals from endemic regions, the origin of CWD in other epizootics is unclear and has not been characterized. Previous studies have shown that there are two distinct strains of CWD. However, the continuous spread and the unclear origin of several outbreaks warrant continued surveillance and further characterization of strain diversity.
Materials and Methods: To address these knowledge gaps, we used biochemical tests to assess strain differences between CWD outbreaks in Michigan, Texas, Missouri, and Colorado, USA. Brain or lymph node samples were homogenized and digested in 50 µg/mL proteinase K (PK). These samples were then run on a Western blot to assess glycoform ratio and electrophoretic mobility. Texas samples were digested in 100 µg/mL PK. To assess conformational stability, brain or lymph node homogenates were incubated in increasing concentrations of guanidine hydrochloride from 0 M to 4 M in 0.5 M increments. Samples were then precipitated in methanol overnight, washed and PK digested in 50 µg/mL PK before slot blotting.
Results: Our results have found significant differences in glycoform ratio between CWD from Michigan and Colorado, but no differences were observed in conformational stability assays. Interestingly, when testing our CWD isolates from Texas to analyse electrophoretic mobility and glycoform ratio, we found that these samples did not exhibit the characteristic band shift when treated with PK, but PK resistant material remained. Additionally, results from our conformational stability assay demonstrate a unique profile of these Texas isolates. Testing of samples from Missouri is currently underway.
Conclusions: Thus far, our data indicate that there are strain differences between CWD circulating in Michigan and CWD in Colorado and provide important insight into CWD strain differences between two non-contiguous outbreaks. We have also identified a unique strain of CWD in Texas with biochemical strain properties not seen in any of our other CWD isolates. These results highlight the importance of continued surveillance to better understand this devastating disease. These results have important implications for CWD emergence, evolution and our understanding of prion strain heterogeneity on the landscape.
www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
CWD TEXAS SUTTON COUNTY FACILITY
www.tahc.texas.gov/news/2023/2023-05-08_CWD_Sutton.pdf
"Initial investigations indicate 10 additional breeding facilities and 18 release sites may have been impacted from previous transfers received from deer that originated in the Sutton County facility."
TEXAS REPUBLICAN SB 1372 TAXPAYERS TO PAY FOR GAME FARMS CWD DEPOPULATION?
SB 1372
A BILL TO BE ENTITLED
AN ACT relating to costs associated with the destruction of certain deer.
BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF TEXAS:
SECTION 1. Section 43.955, Parks and Wildlife Code, is amended to read as follows:
Sec. 43.955. COST OF ASSESSMENT AND DESTRUCTION OF DEER [RECOVERY]. (a) The applicable permit holder shall pay all costs associated with:
(1) an epidemiological assessment conducted under this subchapter to the animal health commission; and
(2) except as provided by Subsection (b), the destruction of deer under this subchapter to the department.
(b) Except as provided by Subsection (c), the department shall waive the costs associated with the destruction under this subchapter of breeder deer at a facility covered by a permit issued under Subchapter L where a breeder deer has tested positive for chronic wasting disease in a test performed by a testing laboratory accredited by the Animal and Plant Health Inspection Service of the United States Department of Agriculture.
(c) The department may not waive costs under Subsection (b) if the department determines that the permit holder or an agent of the permit holder, in violation of this chapter or a regulation of the commission, caused:
(1) the introduction of chronic wasting disease into the facility; or
(2) a delay in the detection of chronic wasting disease at the facility.
SECTION 2. Section 43.955, Parks and Wildlife Code, as amended by this Act, applies only to the payment of costs arising from the destruction of deer commenced on or after the effective date of this Act.
SECTION 3. This Act takes effect immediately if it receives a vote of two-thirds of all the members elected to each house, as provided by Section 39, Article III, Texas Constitution. If this Act does not receive the vote necessary for immediate effect, this Act takes effect September 1, 2023.
legiscan.com/TX/text/SB1372/2023
That can mean the killing of hundreds of expensive animals, and the financial ruin of their rancher.
snip...
“This bill essentially allows Parks and Wildlife to absorb that cost, which we believe helps remove the threat from the landscape quicker, with better landowner relations for the department, and ultimately we think that moves the needle as far as managing the disease,” Dreibelbis said.
snip...
In order to become law, the CWD bill still has to pass the House chamber with a majority vote and then be signed by Gov. Greg Abbott. The chair of the House committee that most recently approved the bill, Rep. Trent Ashby, said in an emailed statement that he was pleased to see the bill making its way through the legislature.
TEXAS REPUBLICAN SB 1372 TAXPAYERS TO PAY FOR CWD TSE PRION DEPOPULATION OF GAME FARMS
The chair of the House committee that most recently approved the bill, Rep. Trent Ashby, said in an emailed statement that he was pleased to see the bill making its way through the legislature.
www.star-telegram.com/news/state/texas/article274737181.html
SO, the taxpayers will have the burden of paying for deer breeders cost of depopulation of their CWD deer herd?...that's crazy if true, and everyone should write Governor Abbott and tell him...taxpayers should not have to pay for game farms cwd depopulation...IMO...terry
what's Governor Abbott history with supporting deer farms?
Governor Abbott on HOW TO LEGISLATE SPREADING CWD TO HELL AND BACK IN TEXAS $$$
i picked up on something that was said, there were several folks complaining that the breeders were getting picked on, and someone said something about trying to 'legislate' there way out of this. folks, this is terrible, i have seen this in other states, and it just spreads cwd even more. hell, it happened right here in Texas in the early days, that's why we are where were at now, you cannot let a bunch of Austin Legislative Socialites regulate CWD, just look what happened in Wisconsin. but i bet this attempted swaying of regulatory power shift from TPWD et al to the Texas Legislature in Austin is happening as we speak. we can't let this happen...
SUNDAY, JANUARY 22, 2017
Texas 85th Legislative Session 2017 Chronic Wasting Disease CWD TSE Prion Cervid Captive Breeder Industry
FRIDAY, JANUARY 27, 2017
TEXAS, Politicians, TAHC, TPWD, and the spread of CWD TSE Prion in Texas
SUNDAY, MAY 14, 2017
85th Legislative Session 2017 AND THE TEXAS TWO STEP Chronic Wasting Disease CWD TSE Prion, and paying to play $$$
Powerful Abbott appointee's lobbying sparks blowback in Legislature
In an ironic twist for Gov. Greg Abbott, who has made ethics reform an urgent political priority, the Texas House is taking aim at what critics call a "pay to play" culture among his appointees.
BY JAY ROOT MAY 12, 2017 12 AM
Houston billionaire Dan Friedkin is chairman of the Texas Parks and Wildlife Commission.
Texas Parks and Wildlife Commission
When Gov. Greg Abbott tapped one of his top campaign donors to become chairman of the Texas Parks and Wildlife Commission, he didn’t get a part-time appointee who would merely draft rules and implement conservation laws passed by the Legislature.
In Dan Friedkin, the governor got a Houston billionaire — with a team of privately funded lobbyists — willing to use his influence to ensure his wildlife interests are taken into account by the Legislature before they pass those laws, interviews and records show.
On the receiving end of that influence, and not in a happy way, is state Rep. Chris Paddie, R-Marshall. Paddie said a lobbyist working for Friedkin’s business empire, which includes a massive South Texas hunting ranch, has been working against his deer breeder management bill, which many large ranchers oppose. The state Parks and Wildlife Department oversees deer breeding regulations in Texas.
“Many times these appointees are well-heeled, very influential people,” Paddie said. “Overall, I feel that it’s inappropriate for an appointee of a board or commission to have personal lobbyists lobbying on issues related to that board or commission.”
Under Texas law, state agencies are barred from lobbying the Legislature. But the powerful people who oversee them aren’t.
If Paddie and dozens of his colleagues get their way, that practice soon will be a Class A misdemeanor.
Last weekend, Paddie attached a ban on appointee lobbying — which would apply to any issues intersecting with their state responsibilities — to an ethics bill that already had powerful friends of the governor in its crosshairs. The provision was adopted unanimously and the bill sailed out of the Texas House on a 91-48 vote Saturday.
The ethics bill, authored by Rep. Lyle Larson, R-San Antonio, would bar big campaign donors from getting appointed by governors in the first place. Anyone who contributed over $2,500 would be barred from serving on state boards and commissions.
Larson pointed to news articles documenting the amount of campaign money appointees have collectively given governors. Last year the San Antonio Express-News calculated that Abbott had received nearly $9 million from people he’s picked for appointed office; before that, a widely cited report from Texans for Public Justice found former Gov. Rick Perry had received $17 million from his own appointees.
Larson said 20 years from now, Texans will be reading the same stories about a future governor unless the Legislature does something about it now.
“We’ve read that article for the last three decades,” Larson said during a brief floor speech. “This is your opportunity to say, 'We need to stop this.' The most egregious ethics violation we’ve got in the state is the pay to play in the governor’s office.”
A prodigious fundraiser, Abbott has put plenty of big donors on prestigious boards and commissions. On the Parks and Wildlife Commission alone, he has installed three mega-donors — pipeline mogul Kelcy Warren, who’s given Abbott more than $800,000 over his statewide political career; Houston businessman S. Reed Morian, who has given $600,000; and Friedkin, who personally donated more than $700,000 — while his Gulf States Toyota PAC gave Abbott another $100,000, according to Ethics Commission records.
Passage of Larson’s HB 3305 represents an ironic twist for Abbott, who for the second session in a row has made ethics reform an urgent political priority — resulting in a bill that's now taking aim at his gubernatorial appointments. Abbott, who has made a habit of ignoring tough questions, hasn't made any public statements about the bill, and his office did not respond to multiple requests for comment.
Friedkin — whose wealth is estimated at $3.4 billion by Forbes — is the owner and CEO of Gulf States Toyota, founded in 1969, which has had the exclusive rights to distribute new Toyotas in Texas and four nearby states. He’d also been a mega-donor to former Gov. Rick Perry, who first appointed Friedkin to the Parks and Wildlife Commission in 2005. Abbott made Friedkin chairman of the commission in 2015.
Requests for comment from Friedkin's office went unanswered.
In addition to his public role as parks and wildlife chairman, a perch that gives him significant influence over deer management issues, Friedkin has private wildlife interests. He owns the sprawling Comanche Ranch in South Texas, according to published news accounts.
The January 2014 edition of Texas Wildlife, published by the Texas Wildlife Association, described Friedkin’s Comanche Ranch as “privately owned and privately hunted” and said it’s “in the business to produce as many trophy bucks as possible, without damaging the native habitat.”
The association, which advocates for private landowners and hunting rights, has locked horns with deer breeding interests at Parks and Wildlife and the Capitol. They compete against each other in the lucrative trophy deer hunting market — and the battle between them perennially spills into the rule-making process at the Parks and Wildlife Commission.
One of their battles centers on how captive deer are tagged so that game wardens and others can distinguish them from native deer. Current law requires a combination of tags and tattoos, and the ranchers and large landowners want to keep it that way. The breeders, meanwhile, favor tagging deer with microchips, which they contend are more accurate and foolproof.
The Wildlife Association said in a Facebook post that removing visible tag or tattoo requirements and allowing microchip tracking “creates real biosecurity risks and blurs ethical lines in the hunting community, as captive deer breeders are allowed to transport and release these animals to be co-mingled with pasture-born deer.” Proponents of the current system say tough rules on breeders are needed to keep out imported deer that may carry Chronic Wasting Disease, which has been found in Texas.
On the other side of the issue is the Texas Deer Association, which represents breeder interests. Executive Director Patrick Tarlton said opposition to his $1.6 billion industry stems less from environmental and health concerns and more from wealthy ranch owners who want to boost profits from trophy-seeking hunters. He notes that Chronic Wasting Disease has been found in both free range and captive deer.
Paddie sided with the breeders by filing House Bill 2855, which would allow breeders to track their deer with microchips instead of relying on physical tags that they say can be torn off.
No one identifying themselves as a Friedkin corporate lobbyist opposed the deer breeding bills during public hearings, according to House and Senate committee records published online.
Behind the scenes, it was a different story.
Paddie said his chief of staff reached out to Laird Doran, one of several lobbyists for Friedkin’s Gulf States Toyota, after hearing that he was trying to convince other legislators to help defeat Paddie's deer microchip bill.
“My chief called him and said, 'Hey, if you’ve got a problem with our bill why aren’t you talking to us?’ ” Paddie said. “He said he represented the Friedkin Group when that happened.”
According to an email from an aide to Sen. Craig Estes, R-Wichita Falls, who is carrying the deer breeding bill in the Senate, Doran also identified himself as a representative of the “Friedkin Group.” That’s the name of the consortium that contains Friedkin's Gulf States Toyota, according to the company’s Linked-In page. He told Estes’ aide that the Friedkin group was opposed to any bill that would “remove requirements for (deer) ear tags,” the senator’s office confirmed.
It’s not clear exactly which Friedkin interests Doran was advancing. Doran is registered at the Texas Ethics Commission with a single entity — Gulf States Toyota — and the agency has no record of a lobbyist working for an entity or individual with the name Friedkin in it, the commission confirmed Wednesday afternoon.
However, Doran checked a variety of non-automotive subject areas in which he is lobbying during this legislative session on behalf of Friedkin’s lucrative distributorship, including “animals,” “parks & wildlife,” “state agencies, boards & commissions,” “environment” and more, his detailed lobby disclosures show.
Doran, director of government relations and senior counsel at the Friedkin Group, did not return phone and email messages left by The Texas Tribune.
Estes said he didn’t have a problem with a governor's appointee engaging in lobbying on issues that affected their private interests, as long as they keep that separate from their state roles.
“I don’t think they should be barred from expressing their views as long as they’re careful to say these are my views, not the views of the agency I’m representing,” Estes said.
But Tarlton, the deer association director, said Friedkin’s use of lobbyists to oppose deer breeders in the Legislature gives the breeders' opponents a huge advantage.
“I think that if the commissioner of Texas Parks and Wildlife is actively lobbying against an industry which his department directly oversees, it absolutely sets up an unfair and closed system of government,” Tarlton said. “The commission is supposed to be the unbiased and equitable oversight for everything wildlife.”
Paddie hopes his amendment to Larsen's ethics bill will even the playing field. He referred to the wealthy Parks and Wildlife chairman (see the 2:29:00 mark in this recorded exchange) when he tacked the appointee-lobbying provision onto Larson’s bill.
Paddie said he’s not singling out anyone. He said it would apply to other powerful gubernatorial appointees in a position to do the same.
“I could have named any number of examples as far as the agencies in particular,” Paddie said. “I want to stop it if anyone serving on any agency is doing this.”
Ryan Murphy contributed to this report.
Disclosure: The Texas Wildlife Association, Texas Parks and Wildlife Department and Gulf States Toyota have been financial supporters of The Texas Tribune. A complete list of Tribune donors and sponsors is available here.
www.texastribune.org/2017/05/12/powerful-abbott-appointees-lobbying-sparks-blowback-legislature/
MONDAY, MAY 15, 2023
TAHC Chapter 40, Chronic Wasting Disease and Scrapie Chapter 60, Singeltary Comment Submission
Greetings TAHC et al,
Thank you kindly for giving me the opportunity to once again comment on CWD and Scrapie.
I want to thank the TAHC and the TPWD for coming together and seems now bring forth sound science, of the real risk factors for both CWD and Scrapie.
With great urgency, i wish to bring your attention on updated Science on Chronic Wasting Disease CWD and Scrapie TSE Prion Environmental Factors and Zoonotic factors, spillover risk factors of CWD and Scrapie to other species i.e. PIGS, our failed feed ban of which now should include all cervid and pigs imo. i saw no mention of atypical Scrapie and the new science from EFSA, i shall include that as well. there is a new TSE Prion disease in a new livestock species the Camel, you should all be aware of. all of this is most important, and should be addressed in any cwd update imo, especially with CWD and Scrapie transmitting to pigs by oral routes.
i will post my concerns below, Thank You Kindly...terry
TAHC Chapter 40, Chronic Wasting Disease and Scrapie Chapter 60, Singeltary Comment Submission
transmissiblespongiformencephalopathy.blogspot.com/2023/05/tahc-chapter-40-chronic-wasting-disease.html
WEDNESDAY, JUNE 14, 2023
Texas TPWD CWD 508 Cases Confirmed To Date
chronic-wasting-disease.blogspot.com/2023/06/texas-tpwd-cwd-508-cases-confirmed-to.html
TUESDAY, MAY 30, 2023
Texas Chronic Wasting Disease Detected in a Free-Range Deer in Bexar County 506 Cases and Mounting
chronic-wasting-disease.blogspot.com/2023/05/texas-chronic-wasting-disease-detected.html
SATURDAY, MAY 27, 2023
TEXAS CWD NOW CONFIRMED 505 Cervid, 101 Wild and 404 associated with breeding facility or breeder release site
chronic-wasting-disease.blogspot.com/2023/05/texas-cwd-now-confirmed-505-cervid-101.html
MONDAY, MAY 08, 2023
TEXAS Chronic Wasting Disease Discovered in Deer Breeding Facility in Sutton County
chronic-wasting-disease.blogspot.com/2023/05/texas-chronic-wasting-disease.html
TUESDAY, APRIL 11, 2023
Texas TAHC Chronic Wasting Disease Discovered in Deer Breeding Facilities in Frio and Hamilton Counties
chronic-wasting-disease.blogspot.com/2023/04/texas-tahc-chronic-wasting-disease.html
TUESDAY, MARCH 21, 2023
Texas CWD seven new cases three separate deer-breeding facilities in Zavala, Washington and Gonzales counties 471 confirmed to date
chronic-wasting-disease.blogspot.com/2023/03/texas-cwd-seven-new-cases-three.html
FRIDAY, FEBRUARY 17, 2023
TEXAS OVERVIEW OF STATE RESPONSE TO CHRONIC WASTING DISEASE CWD TSE PRION April 2019 a Review
chronic-wasting-disease.blogspot.com/2023/02/texas-overview-of-state-response-to.html
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
Greetings APHIS et al, i would kindly like to comment on Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004.
Greetings APHIS et al, i would kindly like to comment on Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004.
***> 1st and foremost your biggest problem is 'VOLUNTARY'! AS with the BSE 589.2001 FEED REGULATIONS, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.
***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.
***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently.
***> 4th Captive Farmed Cervid, INDEMNITY, NO MORE Federal indemnity program, or what i call, ENTITLEMENT PROGRAM for game farm industry. NO MORE BAIL OUTS FROM TAX PAYERS. if the captive industry can't buy insurance to protect not only themselves, but also their customers, and especially the STATE, from Chronic Wasting Disease CWD TSE Prion or what some call mad deer disease and harm therefrom, IF they can't afford to buy that insurance that will cover all of it, then they DO NOT GET A PERMIT to have a game farm for anything. This CWD TSE Prion can/could/has caused property values to fall from some reports in some places. roll the dice, how much is a state willing to lose?
***> 5th QUARANTINE OF ALL FARMED CAPTIVE, BREEDERS, URINE, ANTLER, VELVET, SPERM, OR ANY FACILITY, AND THEIR PRODUCTS, that has been confirmed to have Chronic Wasting Disease CWD TSE Prion, the QUARANTINE should be for 21 years due to science showing what scrapie can do. 5 years is NOT near long enough. see; Infectious agent of sheep scrapie may persist in the environment for at least 16 to 21 years.
***> 6th America BSE 589.2001 FEED REGULATIONS CWD TSE Prion
***> 7TH TRUCKING TRANSPORTING CERVID CHRONIC WASTING DISEASE TSE PRION VIOLATING THE LACEY ACT
***> 8TH ALL CAPTIVE FARMING CERVID OPERATIONS MUST BE INSURED TO PAY FOR ANY CLEAN UP OF CWD AND QUARANTINE THERE FROM FOR THE STATE, NO MORE ENTITLEMENT PROGRAM FOR CERVID GAME FARMING PAY TO PLAY FOR CWD TSE PRION OFF THE TAX PAYERS BACK.
***> 9TH ANY STATE WITH DOCUMENTED CWD, INTERSTATE, NATIONAL, AND INTERNATIONAL MOVEMENT OF ALL CERVID, AND ALL CERVID PRODUCTS MUST BE HALTED!
***> 10TH BAN THE SALE OF STRAW BRED BUCKS AND ALL CERVID SEMEN AND URINE PRODUCTS
***> 11th ALL CAPTIVE FARMED CERVID AND THEIR PRODUCTS MUST BE CWD TSE PRION TESTED ANNUALLY AND BEFORE SALE FOR CWD TSE PRION
SEE FULL SCIENCE REFERENCES AND REASONINGS ;
***> 1st and foremost your biggest problem is 'VOLUNTARY'!
''APHIS created a cooperative, voluntary Federal-State-private sector CWD Herd Certification Program designed to identify farmed or captive herds infected with CWD.''
key word failure is 'voluntary'.
WE know for a fact now that voluntary does NOT WORK!
AS with the BSE 589.2001 FEED REGULATIONS (see , another colossal failure, and proven to be a sham, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.
***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.
***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently. ...snip...see full text submission with science references...TSS
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
www.regulations.gov/comment/APHIS-2021-0004-0002
downloads.regulations.gov/APHIS-2021-0004-0002/attachment_1.pdf
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification
www.regulations.gov/document/APHIS-2018-0011-0003
downloads.regulations.gov/APHIS-2018-0011-0003/attachment_1.pdf
The disease devastating deer herds may also threaten human health
Scientists are exploring the origins of chronic wasting disease before it becomes truly catastrophic.
Rae Ellen Bichell
Image credit: David Parsons/Istock
April 8, 2019
This story was published in collaboration with the Mountain West News Bureau, a collaboration between Wyoming Public Media, Boise State Public Radio in Idaho, KUER in Salt Lake City and KRCC and KUNC in Colorado.
SNIP...
One day in late February, in their laboratory in Fort Collins, Colorado, Wagner and Zabel compared the prions from the brains of CWD-infected deer in Texas with those of elk in Colorado. They want to know if the proteins were all mangled in the same way, or not. “If they are different, this would suggest that we have different strain properties, which is evidence as we're building our case that we might have multiple strains of CWD circulating in the U.S.,” says Wagner.
Step one is to see if they’re equally easy to destroy using a chemical called guanidine. The shape of a prion dictates everything, including the way it interacts with an animal’s cells and the ease with which chemicals can unfold it.
“Moment of truth,” said Wagner, as she and Zabel huddled around a computer, waiting for results to come through. When they did, Zabel was surprised.
“Wow,” he said. “Unlike anything we've seen before.”
The prions from the Texas deer were a lot harder to destroy than the ones from the Colorado elk. In fact, the guanidine barely damaged them at all. “We’ve never seen that before in any prion strain, which means that it has a completely different structure than we've ever seen before,” says Zabel. And that suggests that it might be a very different kind of chronic wasting disease. The researchers ran the same test on another Texas deer, with the same results.
Now, these are only the preliminary results from a few animals. Wagner and Zabel have a lot more experiments to do. But if future tests come to the same conclusion, it would support their hypothesis that there are multiple strains of chronic wasting disease out there, all with different origins. That, in turn, could mean that this disease will become even trickier to manage than it already is.
And, Zabel adds, there’s something else. “If it's still evolving, it may still evolve into a form that could potentially, eventually affect humans,” he says.
Zabel is not the only one worried about that possibility.
OSTERHOLM, THE EPIDEMIOLOGIST from Minnesota, is also concerned. He directs the Center for Infectious Disease Research and Policy at the University of Minnesota, and is serving a one-year stint as a “Science Envoy for Health Security” with the U.S. State Department. In February, he told Minnesota lawmakers that when it comes to chronic wasting disease, we are playing with fire. “You are going to hear from people that this is not going to be a problem other than a game farm issue. You're going to hear from people that it's not going to transmit to people, and I hope they're right, but I wouldn't bet on it,” he said. “And if we lose this one and haven’t done all we can do, we will pay a price.”
If that wasn’t warning enough, he added: “Just remember what happened in England.”
He was talking about mad cow disease. Decades ago, Osterholm got involved in studying the potential for the newly emerging condition — bovine spongiform encephalopathy, or BSE for short — to be transmitted to humans.
At that point, researchers had yet to document a prion disease in animals that could infect people. They did, however, have a few pieces of the puzzle. For one, work in Papua New Guinea had shown that people could transmit prion diseases to each other if they practiced cannibalism, especially of the brain-eating variety. They also knew that BSE was spreading quickly between cattle. Osterholm says he and others worried that the more widespread it became, the more chances it might have to change into something that could sicken people.
“A lot of people thought that it was an overreaction,” says Osterholm. “Then, of course, in 1996, 10 years later, we recognized that in fact transmission had occurred.” Variant Creutzfeldt-Jakob disease, as the illness is called when it appears in human beings, has infected about 230 people worldwide. Osterholm says he feels like he’s having déjà vu, except that instead of mad cow, now it’s chronic wasting disease that’s spreading in animals, with the potential to cross the species barrier to infect humans.
SNIP...SEE FULL TEXT;
www.hcn.org/articles/wildlife-the-disease-devastating-deer-herds-may-also-threaten-human-health-science
***> TEXAS BREEDER DEER ESCAPEE WITH CWD IN THE WILD, or so the genetics would show?
OH NO, please tell me i heard this wrong, a potential Texas captive escapee with cwd in the wild, in an area with positive captive cwd herd?
apparently, no ID though. tell me it ain't so please...
23:00 minute mark
''Free Ranging Deer, Dr. Deyoung looked at Genetics of this free ranging deer and what he found was, that the genetics on this deer were more similar to captive deer, than the free ranging population, but he did not see a significant connection to any one captive facility that he analyzed, so we believe, Ahhhhhh, this animal had some captive ahhh, whatnot.''
youtu.be/aoPDeGL6mpQ?t=1384
Biologists Stress Testing Harvests for Chronic Wasting Disease During Deer Season
Dec. 2, 2022
Media Contact: TPWD News, Business Hours, 512-389-8030
tpwd.texas.gov/newsmedia/releases/?req=20221202b
April 22, 2016
Scrapie Confirmed in a Hartley County Sheep
AUSTIN - Texas Animal Health Commission (TAHC) officials have confirmed scrapie in a Hartley County ewe. The ewe was tested by TAHC after the owner reported signs of weight loss and lack of coordination to their local veterinarian. The premises was quarantined and a flock plan for monitoring is being developed by the TAHC and USDA.
"The TAHC is working closely with the flock owner, sharing all of the options for disease eradication," said Dr. David Finch, TAHC Region 1 Director. "We are thankful the producer was proactive in identifying a problem and seeking veterinary help immediately."
Texas leads the nation in sheep and goat production. Since 2008, there have been no confirmed cases of scrapie in Texas. The last big spike in Texas scrapie cases was in 2006 when nine infected herds were identified and the last herd was released from restrictions in 2013.
According to USDA regulations, Texas must conduct adequate scrapie surveillance by collecting a minimum of 598 sheep samples annually. Since USDA slaughter surveillance started in FY 2003, the percent of cull sheep found positive for scrapieat slaughter (once adjusted for face color) has decreased 90 percent.
Scrapie is the oldest known transmissible spongiform encephalopathies, and under natural conditions only sheep and goats are known to be affected by scrapie. It is a fatal disease that affects the central nervous system of sheep and goats. It is not completely understood how scrapie is passed from one animal to the next and apparently healthy sheep infected with scrapie can spread the disease. Sheep and goats are typically infected as young lambs or kids, though adult sheep and goats can become infected.
The most effective method of scrapie prevention is to maintain a closed flock. Raising replacement ewes, purchasing genetically resistant rams and ewes,or buying from a certified-free scrapie flock are other options to reduce the risk of scrapie. At this time the resistant genetic markers in goats have not been identified, therefore it is important to maintain your sheep and goat herds separately.
The incubation period for Scrapie is typically two to five years. Producers should record individual identification numbers and the seller's premise identification number on purchase and sales records. These records must be maintained for a minimum of five years.
Producers should notify the Texas Animal Health Commission (800-550-8242) or the USDA-Austin Office (512-383-2400) if they have an adult sheep or goat with neurologic signs such as incoordination, behavioral changes, or intense itching with wool loss. Producers may order scrapie identification tags by calling 866-873-2824. For more information, please visit our website at:
www.tahc.texas.gov/animal_health/scrapie/scrapie.htm
web.archive.org/web/20160607024701/http://www.tahc.texas.gov/news/pr/2016/2016-04-22_TAHCScrapie.pdf
Scrapie: The flock identified in April 2016 remains under quarantine in Hartley County.
www.tahc.texas.gov/agency/meetings/minutes/Minutes_CommMtg_2020-09-22.pdf
Scrapie Field Trial Experiments Mission, Texas, The Moore Air Force Base Scrapie TSE Prion Experiment 1964 How Did CWD Get Way Down In Medina County, Texas?
DISCUSSION
Observations of natural outbreaks of scrapie indicated that the disease spread from flock to flock by the movement of infected, but apparently normal, sheep which were incubating the disease.
There was no evidence that the disease spread to adjacent flocks in the absent of such movements or that vectors or other host species were involved in the spread of scrapie to sheep or goats; however, these possibilities should be kept open...
snip...PLEASE READ THE FULL REPORT ON THE SCRAPIE FIELD TRIAL EXPERIMENTS IN MISSION, TEXAS!!!
web.archive.org/web/20030513212324/http://www.bseinquiry.gov.uk/files/mb/m08b/tab64.pdf
4 MOST ENDANGERED WHITETAIL DESTINATIONS IN AMERICA
Mark Kenyon
MARK KENYON Jun 3, 2022
4 Most Endangered Whitetail Destinations in America
It would not be hyperbole to say that we’re quite possibly living in the “golden age” of whitetail deer hunting.
Deer populations might be higher now than ever before and, at least since records have been kept, bigger, older bucks have never been more numerous. Hunters smash world and state records every year. The good times sure seem to be rolling.
But this isn’t true across all aspects or locales within the whitetail range, nor is it guaranteed to remain true into the future. All good things can and do come to an end.
The future of deer and deer hunting, as is the case with almost every aspect of the natural world today, exists on a precipice. Serious threats like disease, habitat loss, resource management, and public opinion all loom on the horizon. Four specific threatened locations, in particular, stand out as representative of larger issues threatening our nation’s deer hunting future. These are, in our estimation, the four most endangered whitetail destinations in America.
Read on for an introduction to these special yet threatened whitetail locales. And find out what we can do as deer hunters and stewards of the land to address the challenges in these specific locations and across the nation.
SOUTHWESTERN WISCONSIN
Greatest Threat: Chronic Wasting Disease
Southwest Wisconsin, a world-renowned big buck destination, is also ground zero for chronic wasting disease. The 100% fatal neurological disease impacting whitetails and other deer species has now spread to 29 states across the country. CWD is widely recognized as possibly the greatest existential threat to the future of whitetail hunting, and no place is it more ubiquitous than Wisconsin’s driftless area.
In some regions here, hunters are observing population-level impacts and CWD prevalence rates have hit as high as 30%. In more practical terms, this means that some areas of the whitetail-crazy state of Wisconsin might be experiencing the beginnings of downward trends in populations due to CWD. Almost one in three deer tested in these areas are testing positive. While CWD’s large-scale impact on deer populations is no joke, an equally concerning risk is the impact that positive tests have on the desire to hunt and eat deer at all. While transmission from deer to humans hasn’t been documented, it’s theoretically possible—akin to what happened with Mad Cow Disease in the 1990s. For this reason, the CDC currently advises hunters not to consume venison from a CWD-positive deer. The result of all this is that a lot of hard-earned venison is getting thrown in the dump already, and things, hypothetically, stand to worsen.
This worst-in-class state of affairs is partly due to a passive approach to CWD management that Wisconsin adopted in 2012, moving away from their “earn a buck” rule, stopping targeted population controls, and making testing in known CWD areas only voluntary.
“Because of the passive management approach taken by Wisconsin, CWD is endemic to five southwest counties, has spread to surrounding counties, and has been found in 38 of the state’s 72 counties,” said southwestern Wisconsin resident, hunter, and land consultant Doug Duren. “In some areas in those counties where prevalence is being studied, over 50% of adult bucks and over 35% of adult does are CWD positive.”
In conversations with other area residents, Duren heard anecdotal reports of seeing fewer older deer and mature bucks, increasing numbers of late-stage infected animals in need of putting down, and already dead deer. “One member of a group of hunters with a lease in Iowa County, Wisconsin told me they decided to give up their lease and find opportunity elsewhere as every buck they killed in the past three years tested positive for CWD,” he said. “This is a cautionary tale.”
While there is no single simple fix to this problem, the recently introduced Chronic Wasting Disease Research and Management Act would designate $35 million in badly needed funding for CWD research and another $35 million for management and surveillance that would certainly help the situation in Wisconsin and beyond. Click here to let your senators know this is an issue of supreme importance to deer hunters in your state.
SNIP...
TEXAS
Greatest Threat: Captive Deer Industry
The great state of Texas sports one of the most robust and proud deer hunting cultures in the nation, but it’s also home to what some consider the greatest threat to deer hunting in all of America: the captive deer industry.
The debate around the captive deer industry is complicated, long-standing, and fraught, but the issues can be distilled into two main categories. First is the well-documented risk of spreading CWD by way of the transfer and sale of captive deer. Second is the negative impact that captive deer shooting facilities, and the media created around them, can have on the public perception of hunting in America and the North American Model of Conservation.
Texas is home to more captive deer facilities than any other state by a long shot, with 858 locations. The conditions present at such facilities, with high numbers of animals in close quarters, are well known to be a perfect storm for the spread of CWD. Not to mention the fact that given the transactional nature of captive deer breeding, many animals are sold and shipped across wide swaths of the country, potentially cross-contaminating new herds of deer all along the way.
While there have been increasing amounts of testing and monitoring of these herds for CWD, the effectiveness of these efforts are feared to be sub-par at best. “The profit motive is so great, it is common for deer breeders to hide infections, or simply not test, and thus spread the disease,” writes Whit Fosborg, CEO of the Theodore Roosevelt Conservation Partnership.
All of this makes Texas a likely ground zero for future CWD issues, a perfect example being a 2021 investigation that identified the release of more than 1,700 deer from seven Texas captive deer facilities that could have been exposed to chronic wasting disease. “Overwhelmingly, the CWD hot zone maps radiate from captive facilities across the state,” said Texas resident and bowhunter K.C. Smith.
Furthermore, the proliferation of captive deer facilities and “canned shooting preserves” threaten to shine a poor light on the larger hunting public, potentially hemorrhaging support for the free-range pursuit of whitetails in Texas and elsewhere. While the vast majority of non-hunters support hunting for food, those figures reverse when considering “trophy hunting.” Animals that are custom-bred to grow the largest antlers possible and then housed in high-fenced small enclosures and sold off to be shot by the highest bidder represents the most egregious example of what trophy hunting could be percieved as. Regardless of whether or not most high-fence facilities fit this description, the worst offenders are unfortunately what most people notice. We as whitetail hunters risk being defined by our most fringe element, especially in the Lone Star state.
It’s important to note that many of the high fence deer facilities in Texas very well might be well-managed and owned by good honest deer-loving people, Smith was quick to remind me. This is not as cut and dry of an issue as some non-Texans want to believe it is.
“I have an easy set of values to live by: don’t hurt people and don’t take their stuff,” he said. “However, when the deer ‘owned’ by another person are threatening to take away the future of my kids’ and everyone’s deer hunting, something must be done.”
Support for the Chronic Wasting Disease Research and Management Act will help just as much here as in Wisconsin, as would advocating for greater oversightof the captive deer industry in Texas and beyond.
www.themeateater.com/wired-to-hunt/whitetail-management/4-most-endangered-whitetail-destinations-in-america
Detection of infectious prions in tissues of feral hogs
PAULINA SOTO1,2, Francisca Bravo-Risi3,4, Rebeca Benavente3, Michael J. Bodenchuk5, Patrick Whitley Whitley6, Clint Turnage6, Tracy A Nichols7, Terry Spraker, Vienna R Brown6, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile. 3Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Chile. 4Universidad Bernardo O’Higgins, Santigo, Chile. 5United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, San Antonio, USA. 6USDA APHIS Wildlife Services, Fort Collins, USA. 7Veterinary Services Cervid Health Program, United States Department of Agriculture, Animal and Plant Health Inspection Service, Fort Collins, USA
Abstract
Chronic wasting disease (CWD) is the prion disease with the greatest potential for spreading, affecting at least seven cervid species. An essential feature of prions lies in their ability to infect some species and not others. This phenomenon, known as a species barrier, seems to be largely dictated by the similarities between the donor (infectious) and recipient prion protein (PrP) sequences. Considering this, some potentially susceptible carnivores are proposed to act as vectors of CWD transmission as they may get infected. Alternatively, predators or scavengers may not get infected but spread infectious particles after they cross their digestive tracts. This project aims to identify the presence of infectious prions in feral hogs living in CWD-endemic areas. To do this, PMCA seeding activity was analyzed on feral hogs tissues such as the brain and retropharyngeal and submandibular lymph nodes using homologous pig PrP substrate or heterologous deer PrP substrate. We furthe! r injected selected feral hogs tissues into mice expressing the cervid and porcine versions of the prion protein to assess their potential to transmit disease. Our results show positive in vitro PrPSc detection using porcine and cervid substrates. The considerably higher detection using cervid substrate suggests that although feral hogs are exposed to CWD prions, disease transmission is inefficient. Bioassays confirmed these results and demonstrated that the infectivity carried by feral hogs is not enough to induce disease. In summary, these results suggest that feral hogs may play a role in disseminating CWD prions across the landscape.
***> In summary, these results suggest that feral hogs may play a role in disseminating CWD prions across the landscape.
=====END
intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
THURSDAY, MARCH 08, 2018
WILD HOGS AND CHRONIC WASTING DISEASE CWD TSE PRION
i have been worried about this for some time, but i don't see why others are not worried as well. these feral hogs that run rampant across states, can dig up a great deal of territory. what else can they dig up? i.e. CWD TSE PRION, and can they spread cwd tse prion to hell and back?
CWD TO PIGS
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Location: Virus and Prion Research
Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Author item Moore, Sarah item Kunkle, Robert item Kondru, Naveen item Manne, Sireesha item Smith, Jodi item Kanthasamy, Anumantha item West Greenlee, M item Greenlee, Justin
Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:
Technical Abstract: Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study, neurological signs consistent with prion disease were observed only in one pig: an intracranially challenged pig that was euthanized at 64 months post-challenge. The purpose of this study was to use an antigen-capture immunoassay (EIA) and real-time quaking-induced conversion (QuIC) to determine whether PrPSc is present in lymphoid tissues from pigs challenged with the CWD agent.
Methods: At two months of age, crossbred pigs were challenged by the intracranial route (n=20), oral route (n=19), or were left unchallenged (n=9). At approximately 6 months of age, the time at which commercial pigs reach market weight, half of the pigs in each group were culled (<6 challenge="" groups="" month="" pigs="" remaining="" the="">6 month challenge groups) were allowed to incubate for up to 73 months post challenge (mpc). The retropharyngeal lymph node (RPLN) was screened for the presence of PrPSc by EIA and immunohistochemistry (IHC). The RPLN, palatine tonsil, and mesenteric lymph node (MLN) from 6-7 pigs per challenge group were also tested using EIA and QuIC.
Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was="">6 months group, 5/6 pigs in the oral <6 4="" and="" group="" months="" oral="">6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). Conclusions:
This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge.
CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease.
Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
www.ars.usda.gov/research/publications/publication/?seqNo115=337105
CONFIDENTIAL
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
web.archive.org/web/20031026000118/www.bseinquiry.gov.uk/files/yb/1990/08/23004001.pdf
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
web.archive.org/web/20030822031154/www.bseinquiry.gov.uk/files/yb/1990/09/10007001.pdf
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
web.archive.org/web/20030822054419/www.bseinquiry.gov.uk/files/yb/1990/09/21009001.pdf
snip...see much more here ;
WEDNESDAY, APRIL 05, 2017
Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Snip…see;
chronic-wasting-disease.blogspot.com/2017/04/disease-associated-prion-protein.html
THURSDAY, MARCH 08, 2018
Cervid, Wild Hogs, Coyotes, Wolves, Cats, Rodents, Gut Piles and Scavengers, A Potential Risk as Regards Disease Transmission CWD TSE Prion
chronic-wasting-disease.blogspot.com/2018/03/cervid-wild-hogs-coyotes-wolves-cats.html
TUESDAY, JUNE 27, 2023
USAHA Report of the Subcommittee on Farmed Cervidae CWD TSE Prion Herds 2015 to 2023
chronic-wasting-disease.blogspot.com/2023/06/usaha-report-of-subcommittee-on-farmed.html
prpsc.proboards.com/thread/128/usaha-reports-farmed-cervidae-herds
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
Paulina Sotoa,b, J. Hunter Reedc, Mitch Lockwoodc, and Rodrigo Moralesa,b aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile; cTexas Parks and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy affecting captive and free-ranging cervids (e.g., mule deer, white-tailed deer, elk, reindeer, and moose). Nowadays, CWD is widely distributed in North America. It is suggested that CWD spreads due to direct animal contact or through exposure to contaminated environments previously inhabited by infected animals. CWD may also be spread through the movement of infected animals and carcasses. Taxidermy practices involve processing deer tissues (or whole animal carcasses). In many cases, the CWD status of processed animals is unknown. This can generate risks of disease spread and transmission. Taxidermy practices include different steps involving physical, chemical, and biological procedures. Without proper tissue handling or disposal practices, taxidermist facilities may become a focus of prion infectivity.
Aims: In this study, we evaluated the presence of infectious prions in a taxidermy facility believed to be exposed to CWD. Detection was performed using the Protein Misfolding Cyclic Amplification (PMCA) technique in biological and inert environmental samples.
Methods: We collected biological and environmental samples (plants, soils, insects, excreta, and others) from a taxidermy facility, and we tested these samples using the PMCA technique. In addition, we swabbed different surfaces possibly exposed to CWD-infected animals. For the PMCA reaction, we directly used a swab piece or 10 µL of 20% w/v homogenized samples. Results: The PMCA analysis demonstrated CWD seeding activity in some of the components of this facility, including insects involved in head processing, soils, and a trash dumpster.
Conclusions: Different areas of this property were used for various taxidermy procedures. We were able to detect the presence of prions in
i) soils that were in contact with the heads of dead animals,
ii) insects involved in the cleaning of skulls, and
iii) an empty dumpster where animal carcasses were previously placed.
This is the first report demonstrating that swabbing is a helpful method to screen for prion infectivity on surfaces potentially contaminated with CWD. These findings are relevant as this swabbing and amplification strategy may be used to evaluate the disease status of other free-ranging and captive settings where there is a concern for CWD transmissions, such as at feeders and water troughs with CWD-exposed properties. This approach could have substantial implications for free-ranging cervid surveillance as well as in epidemiological investigations of CWD.
Funded by: USDA Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Carrot plants as potential vectors for CWD transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Claudio Sotoa, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile
Prion diseases are infectious neurodegenerative disorders afflicting humans and other mammals. These diseases are generated by the misfolding of the cellular prion protein into a disease-causing isoform. Chronic wasting disease (CWD) is a prevalent prion disease affecting cervids (captive and free-range). CWD is thought to be transmitted through direct animal contact or by indirect exposure to contaminated environments. Many studies have shown that infectious prions can enter the environment through saliva, feces, or urine from infected animals and decaying carcasses. However, we do not fully understand the specific contribution of each component to disease transmission events. Plants are logical environmental components to be evaluated since they grow in environments contaminated with CWD prions and are relevant for animal and human nutrition.
Aims: The main objective of this study is to study whether prions are transported to the roots and leaves of carrots, an edible plant commonly used in the human diet and as deer bait.
Methods: We have grown carrot plants in CWD-infected soils. After 90 days, we harvested the carrots and separated them from the leaves. The experiment was controlled by growing plants in soil samples treated with brain extracts from healthy animals. These materials were interrogated for their prion seeding activity using the Protein Misfolding Cyclic Amplification (PMCA) technique. Infectivity was evaluated in mouse bioassays (intracerebral injections in Tg1536 mice). The animals were sacrificed when they showed established signs of prion disease. Animals not displaying clinical signs were sacrificed at 600 days post-inoculation.
Results: The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions, as well as in carrot plants (leaves and roots) grown on them. Bioassays demonstrated that both leaves and roots contained CWD prions in sufficient quantities to induce disease (92% attack rate). As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. Animals treated with soil and plant components exposed with CWD-free brain extracts did not display prion-associated clinical signs or evidence of sub-clinical prion infection.
Conclusions: We show that edible plant components can absorb prions from CWD contaminated soils and transport them to their aerial parts. Our results indicate that plants could participate as vectors of CWD transmission. Importantly, plants designated for human consumption represent a risk of introducing CWD prions into the human food chain.
Funded by: NIH
Grant number: R01AI132695
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
October 6th-12th, 126th Meeting 2022 Resolutions
RESOLUTION NUMBER: 30 Approved
SOURCE: COMMITTEE ON WILDLIFE
SUBJECT MATTER: Chronic Wasting Disease Carcass Disposal Dumpster Management and Biosecurity
BACKGROUND INFORMATION:
State and tribal wildlife agencies may identify collection points (dumpsters) within an identified chronic wasting disease (CWD) management zone for the disposal of hunter-harvested cervid carcasses to remove potentially infected carcasses off the landscape for disposal by an approved method (Gillin & Mawdsley, 2018, chap.14). However, depending on their placement and maintenance these dumpsters could potentially increase the risk of CWD transmission.
In several different states, photographic evidence has shown dumpsters in state identified CWD management zones overflowing with deer carcasses and limbs scattered on the land nearby. This could provide an opportunity for scavengers to potentially move infected carcass material to non-infected zones or increase contamination of the ground material around the dumpster’s location.
Federal guidance does not explicitly address uniform standards for collection locations for carcasses of free-ranging cervids; however, the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services Program Standards on CWD outlines procedures for carcass disposal, equipment sanitation, and decontamination of premises for captive cervid facilities.
RESOLUTION:
The United States Animal Health Association urges the Association of Fish and Wildlife Agencies (AFWA), Wildlife Health Committee to further refine the AFWA Technical Report on Best Management Practices for Prevention, Surveillance, and Management of Chronic Wasting Disease; Chapter 14, Carcass Disposal to address the placement and management of chronic wasting disease carcass disposal dumpsters or other carcass collection containers.
Reference:
1. Gillin, Colin M., and Mawdsley, Jonathan R. (eds.). 2018. AFWA Technical Report on Best Management Practices for Surveillance, Management and Control of Chronic Wasting Disease. Association of Fish and Wildlife Agencies, Washington, D. C. 111 pp.
www.usaha.org/upload/Resolution/2022/2022_Resolution_30_CWD_Dumpste.pdf
ENVIRONMENT FACTORS FOR THE TRANSMISSION OF CWD TSE PRP
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Environment International
Available online 13 June 2022, 107347
Environment International
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Qi Yuana Gag e Rowdenb Tiffany M.Wolfc Marc D.Schwabenlanderb Peter A.LarsenbShannon L.Bartelt-Huntd Jason C.Bartza
a Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178, United States of America
b Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN, 55108, United States of America
c Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, MN, 55108, United States of America
d Department of Civil and Environmental Engineering, Peter Kiewit Institute, University of Nebraska-Lincoln, Omaha, Nebraska, 68182, United States of America
Received 26 April 2022, Revised 8 June 2022, Accepted 9 June 2022, Available online 13 June 2022.
doi.org/10.1016/j.envint.2022.107347
Get rights and content
Under a Creative Commons license Open access
Highlights • An innovative method for prion recovery from swabs was developed.
• Recovery of prions decreased as swab-drying time was increased.
• Recovery of CWD prions from stainless steel and glass was approximately 30%.
• RT-QuIC enhanced CWD prion detection by 4 orders of magnitude.
• Surface-recovered CWD prion was sufficient for efficient RT-QuIC detection.
Abstract
Chronic wasting disease (CWD) has been identified in 30 states in the United States, four provinces in Canada, and recently emerged in Scandinavia. The association of CWD prions with environmental materials such as soil, plants, and surfaces may enhance the persistence of CWD prion infectivity in the environment exacerbating disease transmission. Identifying and quantifying CWD prions in the environment is significant for prion monitoring and disease transmission control. A systematic method for CWD prion quantification from associated environmental materials, however, does not exist. In this study, we developed an innovative method for extracting prions from swabs and recovering CWD prions swabbed from different types of surfaces including glass, stainless steel, and wood. We found that samples dried on swabs were unfavorable for prion extraction, with the greatest prion recovery from wet swabs. Using this swabbing technique, the recovery of CWD prions dried to glass or stainless steel was approximately 30% in most cases, whereas that from wood was undetectable by conventional prion immunodetection techniques. Real-time quake-induced conversion (RT-QuIC) analysis of these same samples resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this method was similar to the original CWD prion load applied to the surface. This combined surface swabbing and RT-QuIC detection method provides an ultrasensitive means for prion detection across many settings and applications.
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5. Conclusions
Chronic wasting disease is spreading in North America and it is hypothesized that in CWD-endemic areas environmental persistence of CWD prions can exacerbate disease transmission. The development of a sensitive CWD prion detection method from environmentally relevant surfaces is significant for monitoring, risk assessment, and control of CWD. In this study, we developed a novel swab-extraction procedure for field deployable sampling of CWD prions from stainless steel, glass, and wood. We found that extended swab-drying was unfavorable for extraction, indicating that hydrated storage of swabs after sampling aided in prion recovery. Recoverable CWD prions from stainless steel and glass was approximately 30%, which was greater than from wood. RT-QuIC analysis of the swab extracts resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude compared to conventional immunodetection techniques. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this developed method was similar to the original CWD prion load without surface contact. This method of prion sampling and recovery, in combination with ultrasensitive detection methods, allows for prion detection from contaminated environmental surfaces.
www.sciencedirect.com/science/article/pii/S0160412022002744?via%3Dihub
Research Paper
Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer
Anthony Ness, Aradhana Jacob, Kelsey Saboraki, Alicia Otero, Danielle Gushue, Diana Martinez Moreno, Melanie de Peña, Xinli Tang, Judd Aiken, Susan Lingle & Debbie McKenzie ORCID Icon show less
Pages 40-57 | Received 03 Feb 2022, Accepted 13 May 2022, Published online: 29 May 2022
Download citation
doi.org/10.1080/19336896.2022.2079888
ABSTRACT
Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.
KEYWORDS: Prion chronic wasting diseasesex differences species differences disease prevalence cervid protein expression glands
www.tandfonline.com/doi/full/10.1080/19336896.2022.2079888
Paper
Rapid recontamination of a farm building occurs after attempted prion removal
Kevin Christopher Gough BSc (Hons), PhD Claire Alison Baker BSc (Hons) Steve Hawkins MIBiol Hugh Simmons BVSc, MRCVS, MBA, MA Timm Konold DrMedVet, PhD, MRCVS … See all authors
First published: 19 January 2019 doi.org/10.1136/vr.105054
The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease.
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This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.
bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
pubmed.ncbi.nlm.nih.gov/30602491/
***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years
***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.
JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12
Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free
Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3
www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82011-0
Front. Vet. Sci., 14 September 2015 | doi.org/10.3389/fvets.2015.00032
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
imageTimm Konold1*, imageStephen A. C. Hawkins2, imageLisa C. Thurston3, imageBen C. Maddison4, imageKevin C. Gough5, imageAnthony Duarte1 and imageHugh A. Simmons1
The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.
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Discussion
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In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination.
journal.frontiersin.org/article/10.3389/fvets.2015.00032/full
***> 172. Establishment of PrPCWD extraction and detection methods in the farm soil
Kyung Je Park, Hoo Chang Park, In Soon Roh, Hyo Jin Kim, Hae-Eun Kang and Hyun Joo Sohn
Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon, Gyeongsangbuk-do, Korea
Conclusions: Our studies showed that PrPCWD persist in 0.001% CWD contaminated soil for at least 4 year and natural CWD-affected farm soil. When cervid reintroduced into CWD outbreak farm, the strict decontamination procedures of the infectious agent should be performed in the environment of CWD-affected cervid habitat.
www.tandfonline.com/doi/full/10.1080/19336896.2019.1615197
THE tse prion aka mad cow type disease is not your normal pathogen.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
***> that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]
www.ncbi.nlm.nih.gov/pubmed/8006664?dopt=Abstract
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
www.pnas.org/content/97/7/3418.full
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
www.ncbi.nlm.nih.gov/pmc/articles/PMC2493038/
MONDAY, APRIL 19, 2021
Evaluation of the application for new alternative biodiesel production process for rendered fat including Category 1 animal by-products (BDI-RepCat® process, AT)
transmissiblespongiformencephalopathy.blogspot.com/2021/04/evaluation-of-application-for-new.html
Detection of protease-resistant cervid prion protein in water from a CWD-endemic area
https://www.ncbi...nlm.nih.gov/pmc/articles/PMC2802782/pdf/prion0303_0171.pdf
A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing
onlinelibrary.wiley.com/doi/10.1111/j.1539-6924.2012.01922.x/abstract
Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals
bmcvetres.biomedcentral.com/track/pdf/10.1186/1746-6148-9-134.pdf
THURSDAY, FEBRUARY 28, 2019
BSE infectivity survives burial for five years with only limited spread
link.springer.com/content/pdf/10.1007%2Fs00705-019-04154-8.pdf
5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!
QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !
FRIDAY, APRIL 30, 2021
Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?
***> Confidential!!!!
***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
and so it seems...
Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years
Published: May 9, 2007
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Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field.
snip...
journals.plos.org/plosone/article?id=10.1371/journal.pone.0000435
Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document
web.archive.org/web/20090505211734/http://www.bseinquiry.gov.uk/files/sc/Seac07/tab03.pdf
Published: 06 September 2021
***> Chronic wasting disease: a cervid prion infection looming to spillover
Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie
Veterinary Research volume 52, Article number: 115 (2021)
veterinaryresearch.biomedcentral.com/articles/10.1186/s13567-021-00986-y
CHRONIC WASTING DISEASE CWD TSE PrP ZOONOSIS ZOONOTIC RISK HUMANS
17 DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.
Rebeca Benavente1, Francisca Bravo1,2, Paulina Soto1,2, J. Hunter Reed3, Mitch Lockwood3, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile. 3Texas Parks and Wildlife, Austin, USA
Abstract
The zoonotic potential of chronic wasting disease (CWD) remains unknown. Currently, there are no known natural cases of CWD transmission to humans but increasing evidence suggests that the host range of CWD is not confined only to cervid species. Alarmingly, recent experimental evidence suggests that certain CWD isolates can induce disease in non-human primates. While the CDC strongly recommends determining CWD status in animals prior to consumption, this practice is voluntary. Consequently, it is plausible that a proportion of the cervid meat entering the human food chain may be contaminated with CWD. Of additional concern is that traditional diagnostic techniques used to detect CWD have relatively low sensitivity and are only approved for use in tissues other than those typically ingested by humans. In this study, we analyzed different processed meats derived from a pre-clinical, CWD-positive free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats. CWD-prion presence in these products were assessed by PMCA using deer and elk substrates. Our results show positive prion detection in all products. To confirm the resilience of CWD-prions to traditional cooking methods, we grilled and boiled the meat products and evaluated them for any remnant PMCA seeding activity. Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking. Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
***> Products tested included filets, sausages, boneless steaks, burgers, ham steaks, seasoned chili meats, and spiced meats.
***> CWD-prion presence in these products were assessed by PMCA using deer and elk substrates.
***> Our results show positive prion detection in all products.
***> Results confirmed the presence of CWD-prions in these meat products suggesting that infectious particles may still be available to people even after cooking.
***> Our results strongly suggest ongoing human exposure to CWD-prions and raise significant concerns of zoonotic transmission through ingestion of CWD contaminated meat products.
=====
9 Carrot plants as potential vectors for CWD transmission.
Paulina Soto1,2, Francisca Bravo-Risi1,2, Claudio Soto1, Rodrigo Morales1,2
1Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, USA. 2Universidad Bernardo O’Higgins, Santiago, Chile
***> We show that edible plant components can absorb prions from CWD-contaminated soils and transport them to their aerial parts.
***> Our results indicate that edible plants could participate as vectors of CWD transmission.
=====
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaoui1,2, Ginny Cheng1,2, Wiebke Wemheuer3, Walter Schulz-Schaeffer3, Sabine Gilch1,2, Hermann Schatzl1,2 1University of Calgary, Calgary, Canada. 2Calgary Prion Research Unit, Calgary, Canada. 3Institute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
***> Further passage to cervidized mice revealed transmission with a 100% attack rate.
***> Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including the oral one.
****> The disease manifested as atypical in macaques and initial transgenic mouse transmissions, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
***> Epidemiologic surveillance of prion disease among cervid hunters and people likely to have consumed venison contaminated with chronic wasting disease
=====
Efficient CWD-like transmission of splenic prions in cervidized transgenic mice: a probable diagnostic marker for CWD infection in humans
Xu Qi, Liuting Qing, Manuel Camacho, Ignazio Cali, Qingzhong Kong
Department of Pathology, Case Western Reserve University, Cleveland, USA
***> Such experimentally generated splenic “humanized” CWD prions (termed eHuCWDsp) appear indistinguishable from prions in the brain of sCJDMM1 patients on Western blot.
=====END
I HAVE NOT READ ALL THESE, BUT THOUGHT SOME OF YOU MIGHT FIND THIS INTERESTING!
kind regards, terry
intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
TEXAS CWD 2023
WEDNESDAY, JUNE 14, 2023
Texas TPWD CWD 508 Cases Confirmed To Date
chronic-wasting-disease.blogspot.com/2023/06/texas-tpwd-cwd-508-cases-confirmed-to.html
***> TEXAS HISTORY OF CWD <***
Singeltary telling TAHC, that CWD was waltzing into Texas from WSMR around Trans Pecos region, starting around 2001, 2002, and every year, there after, until New Mexico finally shamed TAHC et al to test where i had been telling them to test for a decade. 2012 cwd was detected first right there where i had been trying to tell TAHC for 10 years.
***> Singeltary on Texas Chronic Wasting Disease CWD TSE Prion History <***
chronic-wasting-disease.blogspot.com/2017/08/texas-chronic-wasting-disease-cwd-tse.html
TUESDAY, JUNE 27, 2023
USAHA Report of the Subcommittee on Farmed Cervidae CWD TSE Prion Herds 2015 to 2023
chronic-wasting-disease.blogspot.com/2023/06/usaha-report-of-subcommittee-on-farmed.html
prpsc.proboards.com/thread/128/usaha-reports-farmed-cervidae-herds
2023 CWD ZOONOSIS
***> Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.<***
PART 2. TPWD CHAPTER 65. DIVISION 1. CWD
31 TAC §§65.82, 65.85, 65.88
The Texas Parks and Wildlife Commission in a duly noticed meeting on May 25, 2023 adopted amendments to 31 TAC §§65.82, 65.85, and §65.88, concerning Disease Detection and Response, without changes to the proposed text as published in the April 21, 2023, issue of the Texas Register (48 TexReg 2048). The rules will not be republished.
Currently, there is scientific evidence to suggest that CWD has zoonotic potential; however, no confirmed cases of CWD have been found in humans.
www.sos.texas.gov/texreg/archive/June302023/Adopted%20Rules/31.NATURAL%20RESOURCES%20AND%20CONSERVATION.html#57
U of M expert warns of increasing likelihood of CWD transmission to humans
Cathy Wurzer and Gretchen Brown June 5, 2023 1:30 PM
Minnesota scientists have watched chronic wasting disease (CWD) — a fatal, neurological illness — kill deer and elk.
Now, they’re studying its potential to jump to humans.
The University of Minnesota’s Center for Infectious Disease Research and Policy has received more than $1.5 million in state money to start prepping for the possibility of CWD spreading to cows, pigs and possibly humans.
Michael Osterholm, Ph.D. is a world-renowned epidemiologist who heads the center.
He said transmission to humans has not yet been confirmed, but research suggests it is increasingly likely — especially as the disease continues to spread among deer and elk.
“None of us want to believe this could happen,” he told MPR News host Cathy Wurzer. “But you know, as much as you hope it isn't going to happen, hope is not a strategy.”
Current testing can be done only if animals die or are killed, and lymph nodes or brain matter is removed for testing to verify the disease.
That means captive deer often aren’t tested until they die or show symptoms of the disease, and that’s often too late to stop the spread of the disease.
And there aren’t yet adequate tests for humans, Osterholm said — let alone protocols in place if a human were to test positive for the disease.
snip...see;
U of M expert warns of increasing likelihood of CWD transmission to humans
Published: 22 August 2022
www.mprnews.org/episode/2023/06/05/chronic-wasting-disease-in-humans-us-osterholm-prepares-for-whatif?
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bUniversité Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France; cDepartment of Biological Sciences, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
Aims: Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we aimed to determine the zoonotic potential of CWD using a mouse model for human prion diseases.
Material and Methods: Transgenic mice overexpressing human PrPChomozygous for methionine at codon 129 (tg650) were inoculated intracerebrally with brain homogenates of white-tailed deer infected with Wisc-1/CWD1 or 116AG CWD strains. Mice were monitored for clinical signs and were euthanized at terminal disease. Brains were tested by RT-QuIC, western blot upon PK digestion, and immunohistochemistry; fecal homogenates were analyzed by RT-QuIC. Brain/spinal cord and fecal homogenates of CWD-inoculated tg650 mice were inoculated into tg650 mice or bank voles. Brain homogenates of bank voles inoculated with fecal homogenates of CWD-infected tg650 mice were used for second passage in bank voles.
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650 brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
Funded by: We are grateful for financial support from the Natural Sciences and Engineering Research Council of Canada, the National Institutes of Health, Genome Canada, and the Alberta Prion Research Institute. SG is supported by the Canada Research Chairs program.
Acknowledgement: We thank Dr. Trent Bollinger, WCVM, University of Saskatchewan, Saskatoon, Canada, for providing brain tissue from the WTD-116AG isolate, Dr. Stéphane Haïk, ICM, Paris, France, for providing brain tissue from vCJD and sCJD cases, and Dr. Umberto Agrimi, Istituto Superiore di Sanità, Italy, for the bank vole model. We thank animal facility staff for animal care, Dr. Stephanie Anderson for veterinary oversight, and Yo-Ching Cheng for preparing recombinant PrP substrates. Thank you to Dr. Stephanie Booth and Jennifer Myskiw, Public Health Agency of Canada, Canada.
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
actaneurocomms.biomedcentral.com/counter/pdf/10.1186/s40478-021-01262-y.pdf
P35
ADAPTATION OF CHRONIC WASTING DISEASE (CWD) INTO HAMSTERS, EVIDENCE OF A WISCONSIN STRAIN OF CWD
Chad Johnson1, Judd Aiken2,3,4 and Debbie McKenzie4,5 1 Department of Comparative Biosciences, University of Wisconsin, Madison WI, USA 53706 2 Department of Agriculture, Food and Nutritional Sciences, 3 Alberta Veterinary Research Institute, 4.Center for Prions and Protein Folding Diseases, 5 Department of Biological Sciences, University of Alberta, Edmonton AB, Canada T6G 2P5
The identification and characterization of prion strains is increasingly important for the diagnosis and biological definition of these infectious pathogens. Although well-established in scrapie and, more recently, in BSE, comparatively little is known about the possibility of prion strains in chronic wasting disease (CWD), a disease affecting free ranging and captive cervids, primarily in North America. We have identified prion protein variants in the white-tailed deer population and demonstrated that Prnp genotype affects the susceptibility/disease progression of white-tailed deer to CWD agent. The existence of cervid prion protein variants raises the likelihood of distinct CWD strains. Small rodent models are a useful means of identifying prion strains. We intracerebrally inoculated hamsters with brain homogenates and phosphotungstate concentrated preparations from CWD positive hunter-harvested (Wisconsin CWD endemic area) and experimentally infected deer of known Prnp genotypes. These transmission studies resulted in clinical presentation in primary passage of concentrated CWD prions. Subclinical infection was established with the other primary passages based on the detection of PrPCWD in the brains of hamsters and the successful disease transmission upon second passage. Second and third passage data, when compared to transmission studies using different CWD inocula (Raymond et al., 2007) indicate that the CWD agent present in the Wisconsin white-tailed deer population is different than the strain(s) present in elk, mule-deer and white-tailed deer from the western United States endemic region.
www.istitutoveneto.it/prion_09/Abstracts_09.pdf
PRION CONFERENCE 2009
Prion special issue related to the III International Symposium on “The New Prion Biology
www.tandfonline.com/doi/pdf/10.4161/pri.3.4.10772?needAccess=true
www.tandfonline.com/toc/kprn20/3/4?nav=tocList
www.neuroprion.org/
www.certh.gr/dat/EED86597/file.pdf
UPDATE CWD ZOONOSIS AND THE WISCONSIN STRAIN
SUNDAY, APRIL 9, 2023
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
SEE A FEW HIGHLIGHTS;
''Here, we provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model.''
''Furthermore, the presence of infectious prions in feces is concerning because if this occurs in humans, it is a source for human-to-human transmission.'' ''These findings have strong implications for public health and CWD management.''
''We demonstrate that this transgenic line was susceptible to infection with CWD prions and displayed a distinct leading clinical sign, an atypical PrPSc signature and unusual fecal shedding of infectious prions.''
''Importantly, these prions generated by the human PrP transgenic mice were transmissible upon passage.''
Our results are the first evidence of a zoonotic risk of CWD when using one of the most common CWD strains, Wisc-1/CWD1 for ''infection. ''
''Our findings strongly suggest that CWD should be regarded as an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.''
''Indeed, such heterogeneity and distinct seeding activities and infectivity of abnormal PrP fragments was observed in VPSPr cases [20, 43].''
''This implies a high risk of exposure to this strain, e.g., through consumption or handling of infected carcasses, in contrast to rarer CWD strains, and therefore, an actual risk for human health.''
''Fecal shedding of infectious prions, if it occurs in humans, is particularly concerning because of potential human-to-human transmission and adaptation of hCWD.''
Overall, our findings suggest that CWD surveillance in humans should encompass a wider spectrum of tissues/organs tested and include new criteria in the diagnosis of potential patients.
***> PLEASE NOTE;
''Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease-sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and in the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defned by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C- and N-termini, with a molecular weight between 6 and 8 kDa [24, 44–46]. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7–8 kDa fragment (Figs. 2, 4) are very similar to that of GSS, both in terms of migration profle and the N-terminal cleavage site.''
snip...
''CWD in humans might remain subclinical but with PrPSc deposits in the brain with an unusual morphology that does not resemble the patterns usually seen in different prion diseases (e.g., mouse #328; Fig. 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063; Fig. 4), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable. Here, humanized mice inoculated with CWD deer isolates had an atypical onset of the disease with myoclonus (93.75%), before presenting typical clinical signs, generating prions that presented with either atypical biochemical signature (#321 and #3063), shed in feces (#327), or were undetectable by the classical detection methods. The fact that we could not establish a strong correlation between disease manifestation in tg650 mice inoculated with Wisc-1- or 116AG-CWD and the presence of abnormal PrP (Western blot, IHC or RTQuIC) might be explained by the presence of heterogeneous prions in the brains of infected mice with diferent seeding properties in vitro. Indeed, such heterogeneity and distinct seeding activities and infectivity of abnormal PrP fragments was observed in VPSPr cases [20, 43].''
VPSPr, GSS, and CWD zoonosis, concerns there from, where did i hear this concern before?
1. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
link.springer.com/article/10.1007/s00401-022-02482-9
efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
transmissiblespongiformencephalopathy.blogspot.com/2023/04/transmission-of-cervid-prions-to.html
Heterozygosity for cervid S138N polymorphism results in subclinical CWD in gene-targeted mice and progressive inhibition of prion conversion
HIGHLIGHT
However, prion seeding activity was detected in spleens, brains, and feces of these mice, suggesting subclinical infection accompanied by prion shedding.
Infected animals accumulate prions in lymphoreticular and other peripheral tissues, e.g., skeletal muscle, and shed infectious prions in saliva, urine and feces, contributing to direct and environmental transmission and rapidly increasing geographic distribution of CWD (9–12).
However, prion-seeding activity was detectable in the brain, spleen, and feces, indicating subclinical infection and potential for contagiousness.
Heterozygosity for cervid S138N polymorphism results in subclinical CWD in gene-targeted mice and progressive inhibition of prion conversion
Maria I. Arifin orcid.org/0000-0003-2042-3492, Lech Kaczmarczyk orcid.org/0000-0003-2747-3134, Doris Zeng orcid.org/0009-0002-2512-6227, +7, and Sabine Gilch orcid.org/0000-0001-5923-3464 sgilch@ucalgary.caAuthors Info & Affiliations Edited by Reed Wickner, NIH, Bethesda, MD;
received December 12, 2022; accepted March 6, 2023
April 4, 2023
120 (15) e2221060120
doi.org/10.1073/pnas.2221060120
Significance
Amino acid substitutions within the cervid prion protein (PrP) can decrease susceptibility to chronic wasting disease, generally with more prominent effects in homozygous animals. Using novel gene-targeted mouse models expressing S138N reindeer/caribou PrP, we demonstrate subclinical infection with prion seeding activity in spleen and fecal prion shedding in heterozygous 138SN and homozygous 138NN mice. A lower percentage of heterozygous 138SN-PrP than homozygous 138NN-PrP expressing mice harbored seeding-efficient prions in tissues. This is caused by dominant-negative interference of the PrP variants occurring only if they are coexpressed. Our findings are relevant to inform conservation efforts for caribou, an endangered species in North America. Furthermore, our study provides new mechanistic insights into genetic resistance and dominant-negative interference of conversion-competent PrP variants.
Abstract
Prions are proteinaceous infectious particles that replicate by structural conversion of the host-encoded cellular prion protein (PrPC), causing fatal neurodegenerative diseases in mammals. Species-specific amino acid substitutions (AAS) arising from single nucleotide polymorphisms within the prion protein gene (Prnp) modulate prion disease pathogenesis, and, in several instances, reduce susceptibility of homo- or heterozygous AAS carriers to prion infection. However, a mechanistic understanding of their protective effects against clinical disease is missing. We generated gene-targeted mouse infection models of chronic wasting disease (CWD), a highly contagious prion disease of cervids. These mice express wild-type deer or PrPC harboring the S138N substitution homo- or heterozygously, a polymorphism found exclusively in reindeer (Rangifer tarandus spp.) and fallow deer (Dama dama). The wild-type deer PrP-expressing model recapitulated CWD pathogenesis including fecal shedding. Encoding at least one 138N allele prevented clinical CWD, accumulation of protease-resistant PrP (PrPres) and abnormal PrP deposits in the brain tissue. However, prion seeding activity was detected in spleens, brains, and feces of these mice, suggesting subclinical infection accompanied by prion shedding. 138N-PrPC was less efficiently converted to PrPres in vitro than wild-type deer (138SS) PrPC. Heterozygous coexpression of wild-type deer and 138N-PrPC resulted in dominant-negative inhibition and progressively diminished prion conversion over serial rounds of protein misfolding cyclic amplification. Our study indicates that heterozygosity at a polymorphic Prnp codon can confer the highest protection against clinical CWD and highlights the potential role of subclinical carriers in CWD transmission.
snip...
To conclude, our study demonstrates that CWD-infected animals harboring S138N PrP might be “silent spreaders” of CWD prions and highlights the importance of lymphatic tissues in the detection of CWD, particularly in caribou, even in the absence of clinical manifestation. It is important to keep in mind that even protective genotypes may be permissive to certain minor or newly emerging CWD strains. Our results provide new mechanistic insights into dominant-negative inhibition of prion conversion, the tissue specificity of this effect, and suggests that PrPC primary structure is a determinant for tissue-specific prion replication.
www.pnas.org/doi/10.1073/pnas.2221060120
Saturday, April 9, 2022
EFSA EU Request for a scientific opinion on the monitoring of Chronic Wasting Disease (CWD) EFSA-Q-2022-00114 M-2022-00040 Singeltary Submission
efsaopinioncwd.blogspot.com/2022/04/efsa-eu-request-for-scientific-opinion.html
Published: 06 September 2021
***> Chronic wasting disease: a cervid prion infection looming to spillover
Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie
Veterinary Research volume 52, Article number: 115 (2021)
veterinaryresearch.biomedcentral.com/articles/10.1186/s13567-021-00986-y
PRION CONFERENCE 2022 ABSTRACTS CWD TSE PrP ZOONOSIS
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaouia, Ginny Chenga, Wiebke Wemheuerb, Walter J. Schulz-Schaefferb, Sabine Gilcha, and Hermann M. Schätzla aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine & Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bInstitute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
Aims: Chronic wasting disease (CWD) is a prion disease of cervids. Its rapid geographic expansion, shedding of infectivity and persistence in the environment for many years are of concern for humans. Here, we provide the first evidence by transmission experiments to different transgenic mouse models and bank voles that Cynomolgus macaques inoculated via different routes with CWD-positive cervid tissues harbor infectious prions that elicit clinical disease in rodents.
Material and Methods: We used tissue materials from macaques inoculated with CWD to inoculate transgenic mice overexpressing cervid PrPCfollowed by transmission into bank voles. We used RT-QuIC, immunoblot and PET blot analysis to assess brains, spinal cords, and tissues of the gastrointestinal tract (GIT) for the presence of prions.
Results: Our results show that of the macaque materials that induced clinical disease in transgenic mice,73% were from the CNS (46% spinal cord and 27% brain), and 27% were from the spleen, although attack rates were low around 20%. Clinical mice did not display PK-resistant PrPSc(PrPres) in immunoblot, but showed low-levels of prion seeding activity. Transmission into bank voles from clinical transgenic mice led to a 100% attack rate with typical PrPressignature in immunoblot, which was different from that of voles inoculated directly with CWD or scrapie prions. High-level prion seeding activity in brain and spinal cord and PrPresdeposition in the brain were present. Remarkably, we also found prion seeding activity in GIT tissues of inoculated voles. Second passage in bank voles led to a 100% attack rate in voles inoculated with brain, spinal cord and small intestine material from first round animals, with PrPresin immunoblot, prion seeding activity, and PrPresdeposition in the brain. Shortened survival times indicate adaptation in the new host. This also shows that prions detected in GIT tissues are infectious and transmissible. Transmission of brain material from sick voles back to cervidized mice revealed transmission in these mice with a 100% attack rate, and interestingly, with different biochemical signature and distribution in the brain.
Conclusions: Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including oral one. The disease manifested as atypical in macaques and transgenic mice, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
Funded by: The National Institutes of Health, USA, and the Alberta Prion Research Institute/Alberta Innovates Canada. Grant number: 1R01NS121016-01; 201,600,023
Acknowledgement: We thank Umberto Agrimi, Istituto Superiore di Sanità, Rome, Italy, and Michael Beekes, Robert-Koch Institute Berlin, Germany, for providing the bank vole model. We thank the University of Calgary animal facility staff and Dr. Stephanie Anderson for animal care.
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bUniversité Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France; cDepartment of Biological Sciences, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
Aims: Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we aimed to determine the zoonotic potential of CWD using a mouse model for human prion diseases.
Material and Methods: Transgenic mice overexpressing human PrPChomozygous for methionine at codon 129 (tg650) were inoculated intracerebrally with brain homogenates of white-tailed deer infected with Wisc-1/CWD1 or 116AG CWD strains. Mice were monitored for clinical signs and were euthanized at terminal disease. Brains were tested by RT-QuIC, western blot upon PK digestion, and immunohistochemistry; fecal homogenates were analyzed by RT-QuIC. Brain/spinal cord and fecal homogenates of CWD-inoculated tg650 mice were inoculated into tg650 mice or bank voles. Brain homogenates of bank voles inoculated with fecal homogenates of CWD-infected tg650 mice were used for second passage in bank voles.
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650 brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
Funded by: We are grateful for financial support from the Natural Sciences and Engineering Research Council of Canada, the National Institutes of Health, Genome Canada, and the Alberta Prion Research Institute. SG is supported by the Canada Research Chairs program.
Acknowledgement: We thank Dr. Trent Bollinger, WCVM, University of Saskatchewan, Saskatoon, Canada, for providing brain tissue from the WTD-116AG isolate, Dr. Stéphane Haïk, ICM, Paris, France, for providing brain tissue from vCJD and sCJD cases, and Dr. Umberto Agrimi, Istituto Superiore di Sanità, Italy, for the bank vole model. We thank animal facility staff for animal care, Dr. Stephanie Anderson for veterinary oversight, and Yo-Ching Cheng for preparing recombinant PrP substrates. Thank you to Dr. Stephanie Booth and Jennifer Myskiw, Public Health Agency of Canada, Canada.
The chronic wasting disease agent from white-tailed deer is infectious to humanized mice after passage through raccoons
Eric Cassmanna, Xu Qib, Qingzhong Kongb, and Justin Greenleea
aNational Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, IA, USA bDepartments of Pathology, Neurology, National Center for Regenerative Medicine, and National Prion Disease Pathology Surveillance Center, Case Western Reserve University, Cleveland, Ohio, USA
Aims: Evaluate the zoonotic potential of the raccoon passaged chronic wasting disease (CWD) agent in humanized transgenic mice in comparison with the North American CWD agent from the original white-tailed deer host.
Material and Methods: Pooled brain material (GG96) from a CWD positive herd was used to oronasally inoculate two white-tailed deer with wild-type prion protein genotype and intracranially inoculate a raccoon. Brain homogenates (10% w/v) from the raccoon and the two white-tailed deer were used to intracranially inoculate separate groups of transgenic mice that express human prion protein with methionine (M) at codon 129 (Tg40h). Brains and spleens were collected from mice at experimental endpoints of clinical disease or approximately 700 days post-inoculation. Tissues were divided and homogenized or fixed in 10% buffered neutral formalin. Immunohistochemistry, enzyme immunoassay, and western blot were used to detect misfolded prion protein (PrPSc) in tissue.
Results: Humanized transgenic mice inoculated with the raccoon passaged CWD agent from white-tailed deer exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPScwas detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPScalso was detected in brain tissue by western blot and immunohistochemistry. No PrPScwas detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from white-tailed deer did not have detectable PrPScusing conventional immunoassay techniques.
Conclusions: The host range of the CWD agent from white-tailed deer was expanded in our experimental model after one passage through raccoons.
Funded by: This research was funded in its entirety by congressionally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Acknowledgement: We thank Quazetta Brown, Lexi Frese, Rylie Frese, Kevin Hassall, Leisa Mandell, and Trudy Tatum for providing excellent technical support to this project.
Stable and highly zoonotic cervid prion strain is possible
Manuel Camacho, Xu Qi, Liuting Qing, Sydney Smith, Jieji Hu, Wanyun Tao, Ignazio Cali, and Qingzhong Kong Department of Pathology, Case Western Reserve University, Cleveland, USA
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in some areas. Multiple in vitro conversion experiments and in vivo animal studies suggest that the CWD-to-human transmission barrier is not unbreakable. A major public health concern on CWD zoonosis is the emergence of highly zoonotic CWD strains. We aim to address the question of whether highly zoonotic CWD strains are possible.
Material and Methods: We inoculated a few sCJD brain samples into cervidized transgenic mice, which were intended as negative controls for bioassays of brain tissues from sCJD cases who had hunted or consumed vension from CWD-endemic states. Some of these mice became infected and their brain tissues were further examined by serial passages in humanized or cervidized mice.
Results: Passage of sCJDMM1 in transgenic mice expressing elk PrP (Tg12) resulted in a ‘cervidized’ CJD strain that we termed CJDElkPrP. We observed 100% transmission of CJDElkPrPin transgenic mice expressing human PrP (Tg40h). We passaged CJDElkPrPtwo more times in the Tg12 mice. We found that such second and third passage CJDElkPrPprions also led to 100% infection in the Tg40h mice. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice, despite that natural elk CWD isolates and CJDElkPrPshare the same elk PrP sequence.
Conclusions: Our data demonstrate that highly zoonotic cervid prion strains are not only possible but also can be stably maintained in cervids and that CWD zoonosis is prion strain-dependent.
Funded by: NIH
Grant number: R01NS052319, R01NS088604, R01NS109532
Acknowledgement: We want to thank the National Prion Disease Pathology Surveillance Center and Drs. Allen Jenny and Katherine O’Rourke for providing the sCJD samples and the CWD samples, respectively.
Adaptation of chronic wasting disease (CWD) prion strains in hosts with different PRNP genotypes
Camilo Duque Velasqueza,c, Elizabeth Triscotta,c, Chiye Kima,c, Diana Morenoa,c, Judd Aikenb,c, and Debbie McKenziea,c
aDepartment of Biological Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; bDepartment of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; cCentre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
Aims: The contagious nature of CWD epizootics and the PrPCamino acid variation of cervids (and susceptible sympatric species) guarantee the expansion of prion conformational diversity and selective landscapes where new strains can arise. CWD strains can have novel transmission properties including altered host range that may increase zoonotic risk as circulating strains diversify and evolve. We are characterizing the host adaptability of characterized CWD strains as well as CWD isolates from different cervid species in various enzootic regions.
Material and Methods: Characterized CWD strains as well as a number of isolates from hunter-harvested deer were bioassayed in our rodent panel (transgenic mice expressing cervid alleles G96, S96 and H95-PrPC, elk PrPC, bovine PrPC, and both hamsters and non-transgenic laboratory mice). Strain characteristics were compared using computer based scoring of brain pathology (e.g. PrPCWDbrain distribution), western blot and protein misfolding cyclic amplification (PMCA).
Results: Transmission of various isolates resulted in the selection of strain mixtures in hosts expressing similar PrPC, particularly for polymorphic white-tailed deer and for Norwegian reindeer. As of the second passage, transmission of P153 moose prions from Norway has not resulted in emergence of strains with properties similar to any North American CWD strains in our taxonomic collection (Wisc-1, CWD2, H95+and 116AG).
Conclusions: Our data indicates polymorphic white-tailed deer can favor infection with more than one strain. Similar to transmission studies of Colorado CWD isolates from cervids expressing a single PrPCprimary structure, the isolate from Norway reindeer (V214) represents a strain mixture, suggesting intrinsic strain diversity in the Nordfjella epizootic. The diversity of CWD strains with distinct transmission characteristics represents a threat to wildlife, sympatric domestic animals and public health.
Funded by: Genome Canada and Genome Alberta (Alberta Prion Research Institute and Alberta Agriculture & Forestry); NSERC Grant number: #LSARP 10205; NSERC RGPIN-2017-05539
Acknowledgement: We would like to thank Margo Pybus (Alberta Environment and Parks) Trent Bollinger (University of Saskatchewan) for providing us with tissue samples from hunter-harvested deer and Sylvie Benestad for providing moose and reindeer samples.
Application of PMCA to understand CWD prion strains, species barrier and zoonotic potential
Sandra Pritzkowa, Damian Gorskia, Frank Ramireza, Fei Wanga, Glenn C. Tellingb, Justin J. Greenleec, Sylvie L. Benestadd, and Claudio Sotoa aDepartment of Neurology, University of Texas Medical School at Houston, Houston, Texas, USA; bDepartment of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA; cVirus and Prion Research Unit, United States Department of Agriculture, Ames, Iowa, USA; dNorwegian Veterinary Institute, OIE Reference Laboratory for CWD, Ås, Norway
Aims: Chronic wasting disease (CWD) is a prion disease affecting various species of cervids that continues to spread uncontrollably across North America and has recently been detected in Scandinavia (Norway, Sweden and Finland). The mechanisms responsible for the natural transmission of CWD are largely unknown. Furthermore, the risk of CWD transmission to other species, including humans, is also unknown and remains a dangerous enigma. In this study, we investigated the potential of CWD prions to infect several other animal species (sheep, cattle, pig, hamster, and mouse) including humans, by examining their capacity to convert the normal prion protein of distinct species in a PMCA reaction. Moreover, we also investigated whether the in vivo passage of CWD through intermediate species alters their capacity for zoonotic transmission, which may represent a major hazard to human health.
Material and Methods: For these studies, we used brain material from CWD-infected white-tailed deer (Odocoileus virginianus), elk (Cervus canadensis), and mule deer (Odocoileus hemionus) as species native to North America. We also used CWD-infected Moose (Alces alces), reindeer (Rangifer tarandus) and red deer (Cervus elaphus) as Norwegian cervids. We also used brains from cattle, sheep and pigs experimentally infected by CWD. To study interspecies-transmission and zoonotic potential, samples were tested via PMCA for the conversion of PrPCinto PrPScusing different combinations of inoculum and host species. Based on these analyses we estimated the spillover and zoonotic potential for different CWD isolates. We define and quantify spillover and zoonotic potential indices as the efficiency by which CWD prions sustain prion generation in vitro at the expense of normal prion proteins from various mammals and human, respectively.
Results: Our results show that prions from some cervid species, especially those found in Northern Europe, have a higher potential to transmit disease characteristics to other animals. Conversely, CWD-infected cervids originated in North America appear to have a greater potential to generate human PrPSc. We also found that in vivo transmission of CWD to cattle, but not to sheep or pigs substantially increases the ability of these prions to convert human PrPCby PMCA.
Conclusions: Our findings support the existence of different CWD prion strains with distinct spillover and zoonotic potentials. We also conclude that transmission of CWD to other animal species may increase the risk for CWD transmission to humans. Our studies may provide a tool to predict the array of animal species that a given CWD prion could affect and may contribute to understanding the risk of CWD for human health.
Funded by: National Institute of Health Grant number: P01 AI077774
Generation of human chronic wasting disease in transgenic mice
Zerui Wanga, Kefeng Qinb, Manuel V. Camachoa, Ignazio Cali a,c, Jue Yuana, Pingping Shena, Tricia Gillilanda, Syed Zahid Ali Shaha, Maria Gerasimenkoa, Michelle Tanga, Sarada Rajamanickama, Anika Yadatia, Lawrence B. Schonbergerd, Justin Greenleee, Qingzhong Konga,c, James A. Mastriannib, and Wen-Quan Zoua,c
aDepartment of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, USA; bDepartment of Neurology and Center for Comprehensive Care and Research on Memory Disorders, the University of Chicago Pritzker School of Medicine, Chicago, USA; cNational Prion Disease Pathology Surveillance Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; dDivision of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA, USA; eVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA, USA
Aims: Chronic wasting disease (CWD) results from the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC) in the brains of deer and elk. It has been spreading rapidly throughout many regions of North America, exported inadvertently to South Korea, and more recently identified in Europe. Mad cow disease has caused variant Creutzfeldt-Jakob disease (vCJD) in humans and is currently the only known zoonotic prion disease. Whether CWD is transmissible to humans remains uncertain. The aims of our study were not only to confirm whether CWD prion isolates can convert human brain PrPCinto PrPScin vitro by serial protein misfolding cyclic amplification (sPMCA) but also to determine whether the sPMCA-induced CWD-derived human PrPScis infectious.
Material and Methods: Eight CWD prion isolates from 7 elks and 1 deer were used as the seeds while normal human brain homogenates containing either PrP-129 MM (n = 2) or PrP-129 VV (n = 1) were used as the substrates for sPMCA assay. A normal elk brain tissue sample was used as a negative control seed. Two lines of humanized transgenic (Tg) mice expressing either human PrP-129VV or −129 MM polymorphism were included for transmission studies to determine the infectivity of PMCA-amplified PrPSc. Wester blotting and immunohistochemistry and hematoxylin & eosin staining were used for determining PrPScand neuropathological changes of inoculated animals.
Results: We report here the generation of the first CWD-derived infectious human PrPScusing elk CWD PrPScto initiate conversion of human PrPCfrom normal human brain homogenates with PMCA in vitro. Western blotting with a human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPScwas derived from the human brain PrPCsubstrate. Two lines of humanized transgenic mice expressing human PrPCwith either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPScpatterns and neuropathological changes in the brain.
Conclusions: Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSchas the potential to overcome the species barrier and directly convert human PrPCinto infectious PrPScthat can produce bona fide prion disease when inoculated into humanized transgenic mice.
Funded by: CJD Foundation and NIH
Mortality surveillance of persons potentially exposed to chronic wasting disease
R.A. Maddoxa, R.F. Klosb, L.R. Willb, S.N. Gibbons-Burgenerb, A. Mvilongoa, J.Y. Abramsa, B.S. Applebyc, L.B. Schonbergera, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bWisconsin Department of Health Services (WDHS), Division of Public Health, Madison, USA; cNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: It is unknown whether chronic wasting disease (CWD), a prion disease of cervids, can infect people, but consumption of meat from infected animals would be the most likely route of transmission. Wisconsin Department of Health Services, Division of Public Health (WDHS) personnel maintain a database consisting of information collected from hunters who reported eating, or an intention to eat, venison from CWD-positive cervids. These data, collected since 2003, allow for the evaluation of causes of mortality in individuals potentially exposed to CWD.
Material and Methods: The WDHS database contains the name, date of birth, when available, year of CWD-positive deer harvest, and city and state of residence for each potentially exposed individual. The database also includes information on how the deer was processed (self-processed or by a commercial operator) and when applicable, names of others with whom the venison was shared. Duplicate entries (i.e., those who consumed venison from CWD-positive deer in multiple hunt years) are determined by first name, last name, and date of birth. All names in the database are cross-checked with reported cases of human prion disease in Wisconsin and cases in the National Prion Disease Pathology Surveillance Center (NPDPSC) diagnostic testing database. Persons with date of birth available are also cross-checked with prion disease decedents identified through restricted-use national multiple cause-of-death data via a data use agreement with the National Center for Health Statistics (NCHS).
Results: The database currently consists of 1561 records for hunt years 2003–2017 and 87 additional records for 2018–2019. Of these, 657 records have accompanying date of birth; 15 entries were removed as duplicates leaving 642 unique individuals. Of these individuals, 278 of 426 (66%) who ate venison from a CWD-positive deer and provided processing information reported self-processing. No matches were found among any persons in the database cross-checked with WDHS human prion disease surveillance data, NPDPSC data (February 2022 update), and NCHS data through 2020.
Conclusions: Because of the linkage of person and CWD-positive animal in the WDHS database, reviewing the cause of mortality in potentially exposed persons is possible. The number of individuals cross-checked so far is likely only a small percentage of those potentially exposed to CWD in Wisconsin, and many more years of vital status tracking are needed given an expected long incubation period should transmission to humans occur. Nevertheless, the findings of this ongoing review are thus far reassuring.
Prion disease incidence, United States, 2003–2020
R.A. Maddoxa, M.K. Persona, K. Kotobellib, A. Mvilongoa, B.S. Applebyb, L.B. Schonbergera, T.A. Hammetta, J.Y. Abramsa, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: Mortality data, in conjunction with neuropathological and genetic testing results, are used to estimate prion disease incidence in the United States.
Material and Methods: Prion disease decedents for 2003–2020 were identified from restricted-use U.S. national multiple cause-of-death data, via a data use agreement with the National Center for Health Statistics, and from the National Prion Disease Pathology Surveillance Center (NPDPSC) database. NPDPSC decedents with neuropathological or genetic test results positive for prion disease for whom no likely match was found in the NCHS multiple cause-of-death data were added as cases for incidence calculations, while those with negative neuropathology results but with cause-of-death data indicating prion disease were removed. Unmatched cases in the NPDPSC database lacking neuropathological testing but with a positive real-time quaking-induced conversion (RT-QuIC) test result were additionally assessed. Age-specific and age-adjusted average annual incidence rates were calculated from the combined data; the year 2000 as the standard population and the direct method were used for age-adjustment.
Results: A total of 7,921 decedents were identified as having prion disease during 2003–2020 for an age-adjusted average annual incidence of 1.2 per million population. The age-adjusted incidence between males and females (1.3 and 1.1 per million, respectively) differed significantly (p < 0.0001). The age-specific average annual incidence among those <55 and ≥55 years of age was 0.2 and 4.8 per million, respectively; incidence among those ≥65 was 6.1 per million. Eighteen cases were <30 years of age for an age-specific incidence of 8.0 per billion; only 6 of these very young cases were sporadic (3 sporadic CJD, 3 sporadic fatal insomnia), with the rest being familial (9), variant (2), or iatrogenic (1). The age-adjusted annual incidence for the most recent year of data, 2020, was 1.3 per million. However, assessment of RT-QuIC positive cases lacking neuropathology in the NPDPSC database suggested that approximately 20% more cases may have occurred in that year; the addition of a subset of these cases that had date of death information available (n = 44) increased the 2020 rate to 1.4 per million.
Conclusions: Mortality data supplemented with the results of neuropathological, CSF RT-QuIC, and genetic testing can be used to estimate prion disease incidence. However, the identification in the NPDPSC database of RT-QuIC-positive cases lacking date of death information suggests that this strategy may exclude a number of probable prion disease cases. Prion disease cases <30 years of age, especially those lacking a pathogenic mutation, continue to be very rare.
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
ATYPRION project: assessing the zoonotic potential of interspecies transmission of CWD isolates to livestock (preliminary results).
Enric Vidala,b, Juan Carlos Espinosac, Samanta Gilera,b, Montserrat Ordóñeza,b, Guillermo Canteroa,b, Vincent Béringued, Justin J. Greenleee, and Juan Maria Torresc
aUnitat mixta d’Investigació IRTA-UAB en Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; bIRTA. Programa de Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; cCentro de Investigación en Sanidad Animal, CISA-INIA-CSIC, Valdeolmos, Madrid, Spain; dMolecular Virology and Immunology, French National Research Institute for Agriculture, Food and Environment (INRAE), Université Paris-Saclay, Jouy-en-Josas, France; eVirus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, USA
Aims: Since variant Creutzfeldt-Jackob disease was linked to the consumption of bovine spongiform encephalopathy prions, the study of the pathobiological features of animal prions, particularly their zoonotic potential, is of great concern to the scientific community and public health authorities. Furthermore, interspecies transmission of prions has been demonstrated as a putative evolutionary mechanism for prions, that can lead to the emergence of new features including the ability to infect humans. For instance, small ruminants’ atypical scrapie prions, when propagated in a bovine or porcine host, can shift to a classical BSE phenotype thus posing a potential risk in case of human exposure. So far, no hard evidence of zoonotic transmission of cervids’ chronic wasting disease (CWD) to humans has been published, however experimental transmission to bovine, ovine and caprine hosts has been achieved. Our goal is to investigate if, once passaged through these domestic species, CWD prions might become infectious to humans.
Material and Methods: Different CWD isolates experimentally adapted to cattle, sheep and goat (Hamir et al, 2005, 2006, 2007, Greenlee et al 2012) have been intracerebrally inoculated to transgenic mouse models expressing the human cellular prion protein either homozygous for methionine or valine at codon 129 (Tg340-Met129 and Tg362-Val129). Additionally, inocula obtained from experimental transmission of elk CWD to ovinized (Tg501) and bovinized (BoTg110) transgenic mice, as well as white-tailed deer CWD to BoTg110 mice, are currently being bioassayed in both human PrPCtransgenic models.
Results and conclusions: No evidence of transmission has been found on first passage for bovine adapted elk and mule deer CWD to none of the humanized models. The remaining bioassays are ongoing without showing clinical signs yet, as well as second passages for the negative 1stpassages.
Funded by: La Marató de TV3 foundation. Grant number: ATYPRION (201,821–30-31-32)
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Prion 2022 Conference abstracts: pushing the boundaries
www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Prion Conference 2018 Abstracts
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.
Methods
Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).
Results
Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).
Conclusions
While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.
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P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2)
(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.
Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.
We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.
Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.
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P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission
Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
Background
Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.
Methods
We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.
Results
We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.
Conclusions
PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.
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P180 Clinico-pathological analysis of human prion diseases in a brain bank series
Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)
(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.
Background and objective:
The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.
Methods:
We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.
Results:
176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.
Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.
Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.
Discussion:
A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:
www.clinicbiobanc.org/banc-teixits-neurologics/mostres/en_index.html
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P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures
Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)
(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.
Aims:
Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.
Methods:
Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.
Results:
The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.
Conclusions:
Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.
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WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)
(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
See also poster P103
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
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WA16 Monitoring Potential CWD Transmission to Humans
Belay ED
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.
The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.
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P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan
Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)
(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.
Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.
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Source Prion Conference 2018 Abstracts
www.ncbi.nlm.nih.gov/pmc/articles/PMC6738495/
transmissiblespongiformencephalopathy.blogspot.com/2018/05/prion-2018-may-22-25-2018-santiago-de.html
chronic-wasting-disease.blogspot.com/2018/07/oral-transmission-of-cwd-into.html
prionconference.blogspot.com/2018/
Volume 24, Number 8—August 2018 Research Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions
Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)
Abstract Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted.
snip...
Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).
A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.
The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.
In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).
The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.
Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.
Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.
This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.
Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.
wwwnc.cdc.gov/eid/article/24/8/16-1888_article
www.ed.ac.uk/clinical-brain-sciences/news/news-jul-dec-2018/cwd-prions-human-conversion
Prion 2017 Conference Abstracts
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen
This is a progress report of a project which started in 2009.
21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves.
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice.
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation.
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS ABSTRACTS REFERENCE
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
SATURDAY, FEBRUARY 23, 2019
Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019
chronic-wasting-disease.blogspot.com/2019/02/chronic-wasting-disease-cwd-tse-prion.html
TUESDAY, NOVEMBER 04, 2014
Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011 Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "
chronic-wasting-disease.blogspot.com/2014/11/six-year-follow-up-of-point-source.html
Transmission Studies Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
snip....
web.archive.org/web/20090506002237/http://www..bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿
Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.
jvi.asm.org/content/83/18/9608.full
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.
science.sciencemag.org/content/311/5764/1117..long
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE. see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence
? “Our conclusion stating that we found no strong evidence of CWD transmission to humans” From: TSS Subject: CWD aka MAD DEER/ELK TO HUMANS
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam, In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091).
Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message----- From:
Sent: Sunday, September 29, 2002 10:15 AM To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip... *** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
snip... full text ;
chronic-wasting-disease.blogspot.com/2008/04/prion-disease-of-cervids-chronic.html
> However, to date, no CWD infections have been reported in people.
sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven. if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;
sporadic = 54,983 hits
www.ncbi.nlm.nih.gov/pubmed/?term=sporadic
spontaneous = 325,650 hits
www.ncbi.nlm.nih.gov/pubmed/?term=spontaneous
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD.
SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys
www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true
wwwnc.cdc.gov/eid/article/20/1/13-0858_article
CWD TSE PRION AND ZOONOTIC, ZOONOSIS, POTENTIAL
Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY
Date: Fri, 18 Oct 2002 23:12:22 +0100
From: Steve Dealler
Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member
To: BSE-L@ References:
Dear Terry,
An excellent piece of review as this literature is desperately difficult to get back from Government sites.
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
Steve Dealler ===============
caninespongiformencephalopathy.blogspot.com/2010/03/canine-spongiform-encephalopathy-aka.html
''The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).''
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss) These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).
The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (
...TSS)snip...see full report ;
web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf
web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf
Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk
BSE Inquiry Steve Dealler
Management In Confidence
BSE: Private Submission of Bovine Brain Dealler
snip...see full text;
MONDAY, FEBRUARY 25, 2019
***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
bseinquiry.blogspot.com/2019/02/mad-dogs-and-englishmen-bse-scrapie-cwd.html
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