US Captive CWD Positive Herds Update April 2025
US Captive CWD Positive Herds Update April 2025
CHRONIC WASTING DISEASE CWD CASESDate of Index Case Confirmation Index Case State County Species Herd Type HCP Enrolled HCP Certified Number of Animals Herd Status
4/9/2025 6 YR Male MI Montcalm WTD Breeder No No 86 Quarantine
3/28/2025 3.5 YR Male PA Huntingdon WTD Hobby No No 2 Quarantine
3/28/2025 3.5 YR Female PA Wayne Red Deer Hunt No no 31 Quarantine
2/26/2025 1.5 YR Male TX Kauffman WTD Breeder Yes Yes 400 Quarantine
2/26/2025 3.5 Yr Male PA Lancaster WTD Breeder Yes Yes 105 Quarantine
2/21/2025 4 YR Male CO Montrose Elk Hunt No No 97 Quarantine
2/21/2025 7 YR Female MI Osceola WTD Hunt No No 201 Quarantine
2/10/2025 3.5 YR Male PA Perry WTD Hunt No No 15 Quarantine
1/7/2025 4 YR Female CO Mesa Elk Hunt No No 217 Quarantine
1/7/2025 2 YR Male UT Duchesne Elk Hunt No No 0 No animals
12/30/2024 4 YR Female ID Jefferson Elk Breeder No No 197 Quarantine
Updated April 2025
https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf
These quarantined CWD positive herds are a ticking time bomb waiting go off while waiting for litigation of the fate of the CWD positive herds, all the while saturating surrounding land, water, environment, other species, that may come into contact. Some of these CWD infected farms can sometimes lead upward to 80% CWD infection rate. An extremely foolish and dangerous policy to quarantine CWD positive herds, at this time, imo…terry
Texas CWD Surveillance Positives Tracking Page is still extremely outdated!
https://tpwd.texas.gov/huntwild/wild/diseases/cwd/positive-cases/listing-cwd-cases-texas.phtml#texasCWD
My last figures of Texas CWD Totals To Date were 1061 Confirmed, but that is way outdated now as well.
Texas CWD total by calendar years
https://chronic-wasting-disease.blogspot.com/2024/12/texas-cwd-tse-prion-positive-samples-by.html
Counties where CWD Exposed Deer were Released
https://tpwd.texas.gov/documents/257/CWD-Trace-OutReleaseSites.pdf
Number of CWD Exposed Deer Released by County
https://tpwd.texas.gov/documents/258/CWD-Trace-OutReleaseSites-NbrDeer.pdf
“Chronic Wasting Disease (CWD) is a fatal neurological disease and can devastate deer populations by silently spreading through direct animal contact and contaminated environments. Without close monitoring, illegal movement of captive deer increases the risk of introducing CWD to areas it is not known to exist, potentially leading to widespread outbreaks which will impact more than just the health of Texas deer.”
https://tpwd.texas.gov/newsmedia/releases/?req=20250227b
Texas Game Wardens Bust Illegal Deer Operations Across the State Feb. 27, 2025
Media Contact: TPWD News, Business Hours, 512-389-8030
AUSTIN – A recent investigation by Texas Game Wardens resulted in approximately 1,200 pending charges and 22 suspects from across the state involved in the deer breeding industry and black-market wildlife trade.
The suspects and charges are associated with three deer breeding facilities, ten release sites, one deer management pen and three illegal facilities not registered in the Texas Wildlife Information Management Services (TWIMS) database, meaning they were operating or receiving deer in violation of registration requirements and disease monitoring protocols.
"The hard work and commitment of our Texas Game Wardens to uncover these violations cannot be overstated," said TPWD Executive Director David Yoskowitz. "Their pivotal role in conservation law enforcement helps ensure the health of all deer populations in the state. These violations don’t just break the law—they undermine the very foundation of responsible wildlife management in Texas."
Texas Parks and Wildlife Department (TPWD) has referred the cases to prosecutors’ offices in 11 Texas counties.
The cases stem from a prior investigation involving the illegal smuggling of captive white-tailed deer, ultimately leading wardens to uncover this much larger network of alleged offenders after the arrest and conviction of two individuals that occurred in Montgomery County.
The investigation uncovered approximately 500 Class C charges, 700 Class B charges, 22 Class A charges and multiple state jail felony charges. Due to the ongoing nature of this case, the final number of charges filed may vary.
"I am incredibly proud of the dedication and diligence Texas Game Wardens devoted to this case," said Col. Ronald VanderRoest, TPWD law enforcement director. "An operation of this size and scope did not develop overnight and the widespread violations may have continued unchecked, posing an even greater threat to Texas’ deer populations and the integrity of the deer breeding industry, if not for their hard work.”
TPWD has established science-based regulations and procedures to both manage deer breeding in Texas and prevent major disease outbreak, all with the goal of ensuring the long-term sustainability of native and captive deer in Texas.
Chronic Wasting Disease (CWD) is a fatal neurological disease and can devastate deer populations by silently spreading through direct animal contact and contaminated environments. Without close monitoring, illegal movement of captive deer increases the risk of introducing CWD to areas it is not known to exist, potentially leading to widespread outbreaks which will impact more than just the health of Texas deer.
Yoskowitz also noted that with many rural Texans depending on hunting as their full or supplemental income, a large-scale outbreak of CWD could pose a significant threat to white-tailed deer hunting, which has a $9.6 billion annual economic contribution and could irreversibly alter Texas’ rich outdoor heritage.
By circumventing requirements, disregarding regulations and falsifying official records, the suspects in this case intentionally placed the state’s entire deer population at risk, explained VanderRoest.
"These individuals and ranches operated with impunity, repeatedly violating established laws designed to protect Texas’ natural resources and safeguard the state’s wildlife against disease transmission," VanderRoest said. "Systematic abuse of the regulatory framework governing the deer breeding industry will not be tolerated as we focus on our mission of conservation law enforcement."
Class C pending charges include transferring deer without valid antemortem CWD tests, lack of identifying tattoos or valid transfer permits, failure to report mortality within the required seven-day period following detection and failure to submit CWD samples within seven days of collection. Additional pending charges include illegally selling and purchasing wild white-tailed deer and hunting deer in a closed season to falsify and circumvent CWD testing requirements by submitting samples from free-ranging wild white-tailed deer in place of breeder deer.
Class B pending charges include possession of wild deer in breeder facilities to replace dead breeder deer, multiple Trap, Transport and Transplant (TTT) permit violations and criminal mischief for the destruction of county and state property.
TTT charges stem from the illegal trapping, transporting and transplanting of free-ranging white-tailed deer for release for hunting, trapping previously released wild deer and reselling them, illegal operation of unregistered facilities participating in the same TTT activities and the undocumented and unauthorized transportation and release of unidentified fawns.
Suspects face Class A charges for taking white-tailed deer without landowner consent and for hunting exotic animals from a public roadway or right of way.
Pending state jail felony charges include tampering with government records falsifying information in TWIMS reports, which were certified as accurate. These incidents include falsifying tests through the submission of tissue samples from poached wild deer for CWD testing in place of the samples of breeder deer, tag swapping between breeder deer, and swapping tags between breeder deer and replacement deer captured in the wild.
TPWD remains committed to enforcing these laws and will hold violators accountable. Texas Game Wardens will continue to pursue those who disregard regulations and illegally exploit Texas’ natural resources, putting both captive and native populations at risk.
About Texas Game Wardens
Texas Game Wardens, within the Law Enforcement Division of TPWD, are responsible for enforcing laws related to the conservation and management of natural resources and public safety through community-based law enforcement. Their mission is to provide hunting, fishing and outdoor recreation opportunities for the use and enjoyment of present and future generations. Additionally, they play a crucial role in search and rescue operations during natural disasters, exemplifying their commitment to protecting both the environment and the people of Texas.
If you witness a wildlife violation in progress, please call 1-800-792-GAME (4263) immediately and report it to Operation Game Thief (OGT), Texas’ Wildlife Crime-Stoppers Program. Dispatchers are available 24/7. Reports can be made anonymously, and tipsters may be eligible for rewards up to $1,000 for information leading to a conviction.
Department records indicate that within the last five years (since January 1, 2020), 30 deer breeding facilities where CWD has been confirmed transferred a total of 8,799 deer to 249 additional deer breeding facilities and 487 release sites located in a total of 144 counties in Texas.
https://www.sos.state.tx.us/texreg/pdf/backview/0411/0411adop.pdf
TUESDAY, FEBRUARY 25, 2025
TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update February 25, 2025
TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update
AUDIT SUBCOMMITTEE MEETING AGENDA February 25, 2025, 8:00 A.M
https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
OfficialCommissionMeetingBook423.pdf
http://web.archive.org/web/20250225154629/https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
snip...
Chronic Wasting Disease (CWD): There have been seven positive breeding facilities since January 1, 2024. Dr. Jessica Monday, TAHC State Epidemiologist, will give an update under Agenda Item #9.
https://chronic-wasting-disease.blogspot.com/2025/02/texas-animal-health-commission-423rd.html
http://web.archive.org/web/20250225154629/https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
Chronic Wasting Disease Detected in Kaufman County Deer Breeding Facility
March 10, 2025
Media Contact: TPWD News, Business Hours, 512-389-8030
News
AUSTIN – Texas Parks and Wildlife Department (TPWD) received confirmation of two cases of chronic wasting disease (CWD) in a Kaufman County deer breeding facility. This is the first CWD detection in a deer breeding facility in the county.
Two white-tailed deer – a 20-month-old male and an eight-month-old female — tested positive through ante-mortem testing conducted to meet CWD surveillance requirements prior to transferring deer from the registered deer breeding facility. Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) initially analyzed the samples, and the National Veterinary Services Laboratory in Iowa confirmed the CWD detection.
CWD has an incubation period that can span years, so the first indication of the disease in a herd is often found through surveillance testing rather than observed clinical signs. Permitted deer breeding facilities must test all mortalities within the facility and conduct ante-mortem testing on any deer prior to movement from the facility, in compliance with surveillance and testing requirements. This positive facility and its premises were placed under a quarantine by Texas Animal Health Commission (TAHC) to help prevent spread of disease from the facility. TPWD and TAHC will be working with the facility owner to develop a herd plan to address disease mitigation in the facility.
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 process continues, 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, regulations, and CWD best management practices for hunters and landowners, visit TPWD’s CWD page.
https://tpwd.texas.gov/newsmedia/releases/?req=20250310a
FRIDAY, JANUARY 10, 2025
TAHC Chronic Wasting Disease Detected in Brown County High-Fence Release Site
AUSTIN, TX – Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of one case of chronic wasting disease (CWD) in a Brown County high fence ranch, marking the first confirmed detection in the county.
A three and a half-year-old female white-tailed deer tested positive through postmortem testing conducted to meet CWD surveillance requirements for a site epidemiologically traced to a CWD-positive facility. Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) initially analyzed the samples, and the National Veterinary Services Laboratory in Iowa confirmed the CWD detection.
The detection occurred on a ranch registered as a deer breeder release site and identified as having received deer from a CWD-positive breeding facility reported in 2024.
CWD has an incubation period that can span years, so the first indication of the disease in a herd is often found through surveillance testing rather than observed clinical signs. Testing hunter-harvested deer allows animal health officials to assess disease presence and was required as part of the quarantine issued for this property epidemiologically traced to a facility with a CWD-positive detection.
Landowners and hunters are encouraged to implement sound wildlife management practices, such as adequate deer harvest and management of healthy native habitat, to help mitigate disease impacts on the deer populations, especially in areas where CWD has been detected.
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 process continues, 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, regulations, and CWD best management practices for hunters and landowners, visit TPWD’s CWD page or TAHC’s CWD page.
###
January 10, 2025
TAHC Chronic Wasting Disease Detected in Brown County High-Fence Release Site
https://www.tahc.texas.gov/news/2025/2025-01-10-CWD_BrownCo.pdf
Texas Kimble County Farm Chronic Wasting Disease CWD TSE Prion Approximate Herd Prevalence 12%
SUMMARY MINUTES OF THE 407th COMMISSION MEETING Texas Animal Health 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.
https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22
http://web.archive.org/web/20201017124040/https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22.pdf
Wisconsin CWD
2025 CWD Wisconsin and Texas, and ramifications from the past, shall we…
Wisconsin DNR says CWD sinking deer herds in disease-endemic areas
PATRICK DURKIN Outdoors Columnist
CWD culprits
Snip…
“We can now say it’s not EHD (epizootic hemorrhagic disease), it’s not coyotes, it’s not bobcats, and it’s not earn-a-buck regulations from 15 years ago that are causing the herd declines we’re seeing,” said Dan Storm, the study’s chief researcher. “CWD is the cause, and we have solid evidence to back it up. This is what’s going on, and so let’s proceed with what to do about it.”
“We already did that and look how it went,” Storm said. “Before we lost earn-a-buck (in 2011), hunters dropped Iowa County’s deer herd below 20,000. After earn-a-buck, the herd took 7%, 10% and 12% annual increases until 2020. That herd should have kept growing, but it didn’t. CWD is pulling it down and boxing it in.”
The DNR’s annual post-hunt population estimates show Iowa County’s herd rose 51.3% from 16,900 in 2011 to 25,566, the 2018-2020 three-year average. The herd has since fallen 15.25% to 21,666, the 2021-2023 three-year average.
Bryan Richards, CWD project leader at the USDA’s National Wildlife Health Center in Madison, said backing off would backfire. “You won’t recover a population by letting CWD run its course,” Richards said. “When you try to stockpile deer by not shooting, you protect sick deer, too. Contamination worsens and the healthy proportion of the herd declines. Shooting removes sick deer from the herd sooner than CWD will. They’ll spread fewer prions over time, and you’ll probably shoot them before CWD reaches its worst stages for shedding prions.”
Storm put it this way: “The more CWD you have in your area, the more the herd will decline.” Which areas already exceed 29% infection rates for adult does? The latest DNR data from a year ago shows southeastern Richland County on the edge at 27%, northwestern Iowa County at 35%, and the Devil’s Lake area in eastern Sauk County at 34%.
Further, CWD testing of hunter-killed deer in autumn 2024 shows overall (bucks and does) detection rates at or above 29% in six townships (6-mile by 6-mile areas) in Columbia County, three townships in Dane County, eight townships in Iowa County, 11 townships in Richland County, and 15 townships in Sauk County.
How low will deer populations drop where CWD is endemic? Storm said CWD won’t exterminate deer, but no one can predict how it will affect specific valleys, woodlands or watersheds. CWD has spread at varying rates in different Wisconsin habitats, and appears to have leveled off at high infection rates in some areas while still rising and spreading in others.
The disease has so far been verified in wild deer in 48 of Wisconsin’s 72 counties, even though testing has been totally voluntary for years. During the 2024 hunting season, 1,755 more deer tested positive for CWD across the state, a record 10.4% detection rate despite the least amount of samples (16,939) volunteered since 2017. Richland County hunters provided the most samples, 1,335, in 2024, and 444 (33.4%) had CWD.
https://www.antigojournal.com/sports/outdoors/durkin-wisconsin-dnr-says-cwd-sinking-deer-herds-in-disease-endemic-areas/article_cb73b5ca-dd9e-11ef-853c-d3fb206ddf8c.html
18% of mule deer in northeastern Montana have deadly chronic wasting disease “In the 2024-25 hunting FWP submitted 9,066 samples for chronic wasting disease testing – the largest number of CWD samples ever collected in a single year. More than 1,100 of these samples were collected by hunters. Of those samples, 335 tested positive for the disease, including 202 white-tailed deer, 127 mule deer and six elk.”
https://billingsgazette.com/outdoors/article_de5278b8-f2e1-11ef-b479-cf42652717a4.html
Wisconsin Caltive CWD Positives update 1/30/2024
HOLY SMOKES Wisconsin Captive CWD Positives update January 2024
Chronic Wasting Disease Positives in Farm-raised Deer Revised: 1/30/2024
https://datcp.wi.gov/Documents/WI%20CWD%20Positives1.pdf
https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf
Wisconsin CWD year 2024
DNR Zone # Sampled # Analyzed Positive for CWD
Central Farmland Zone 7100 7100 175
Central Forest Zone 628 628 18
Northern Forest Zone 1850 1850 5
Southern Farmland Zone 7494 7483 1573
Unknown Zone 31 29 0
Totals: 17103 17090 1771
https://apps.dnr.wi.gov/cwd/summary/YearZone/2024
https://dnr.wisconsin.gov/topic/WildlifeHabitat/registersample
https://dnr.wisconsin.gov/topic/WildlifeHabitat/results
https://datcp.wi.gov/Pages/Programs_Services/FarmRaisedDeer.aspx
https://datcp.wi.gov/Pages/Programs_Services/FRDHerdStatusPrograms.aspx
https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf
Iowa 79.8 percent of the deer tested positive CWD and Wisconsin Buckhorn Flats Nearly 80% CWD positive
For Immediate Release
Thursday, October 2, 2014 Dustin Vande Hoef 515/281-3375 or 515/326-1616 (cell) or Dustin.VandeHoef@IowaAgriculture.gov
TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE RELEASED 79.8 percent of the deer tested positive for the disease
DES MOINES – The Iowa Department of Agriculture and Land Stewardship today announced that the test results from the depopulation of a quarantined captive deer herd in north-central Iowa showed that 284 of the 356 deer, or 79.8% of the herd, tested positive for Chronic Wasting Disease (CWD). The owners of the quarantined herd have entered into a fence maintenance agreement with the Iowa Department of Agriculture and Land Stewardship, which requires the owners to maintain the 8’ foot perimeter fence around the herd premises for five years after the depopulation was complete and the premises had been cleaned and disinfected
CWD is a progressive, fatal, degenerative neurological disease of farmed and free-ranging deer, elk, and moose. There is no known treatment or vaccine for CWD. CWD is not a disease that affects humans.
On July 18, 2012, USDA Animal and Plant Health Inspection Service’s (APHIS) National Veterinary Services Lab in Ames, IA confirmed that a male white tail deer harvested from a hunting preserve in southeast IA was positive for CWD. An investigation revealed that this animal had just been introduced into the hunting preserve from the above-referenced captive deer herd in north-central Iowa.
The captive deer herd was immediately quarantined to prevent the spread of CWD. The herd has remained in quarantine until its depopulation on August 25 to 27, 2014.
The Iowa Department of Agriculture and Land Stewardship participated in a joint operation to depopulate the infected herd with USDA Veterinary Services, which was the lead agency, and USDA Wildlife Services.
Federal indemnity funding became available in 2014. USDA APHIS appraised the captive deer herd of 376 animals at that time, which was before depopulation and testing, at $1,354,250. At that time a herd plan was developed with the owners and officials from USDA and the Iowa Department of Agriculture and Land Stewardship.
Once the depopulation was complete and the premises had been cleaned and disinfected, indemnity of $917,100.00 from the USDA has been or will be paid to the owners as compensation for the 356 captive deer depopulated.
The Iowa Department of Agriculture and Land Stewardship operates a voluntary CWD program for farms that sell live animals. Currently 145 Iowa farms participate in the voluntary program. The above-referenced captive deer facility left the voluntary CWD program prior to the discovery of the disease as they had stopped selling live animals. All deer harvested in a hunting preserve must be tested for CWD.
-30-
https://www.iowaagriculture.gov/press/2014press/press10022014.asp
http://web.archive.org/web/20141006172620/https://www.iowaagriculture.gov/press/2014press/press10022014.asp
Wisconsin Buckhorn Flats CWD
SUBJECT: Almond Deer Farm Update
The first case of Chronic Wasting Disease (CWD) among Wisconsin's farm-raised deer occurred in a white-tailed deer buck shot by a hunter at the property (formerly known as Buckhorn Flats) in September 2002. This situation prompted the eventual depopulation of the entire farm.
The deer, a mix of does and yearlings, were destroyed on January 17, 2006- 4 years later- by U.S. Department of Agriculture shooters under a USDA agreement with the farm owner.
Sixty of the 76 animals tested positive for CWD. The 76 deer constituted the breeding herd in the breeding facility on the farm. The property also had a hunting preserve until 2005. Four deer, two does and two fawns, the only deer remaining in the former preserve, were killed and tested as well. CWD was not detected in those animals.
The total number of deer to test positive from this farm from the initial discovery to final depopulation is 82. The nearly 80% prevalence rate discovered on Buckhorn Flats is the highest prevalence recorded in any captive cervid operation in North America.
Tuesday, December 20, 2011
Chronic Wasting Disease CWD WISCONSIN Almond Deer
(Buckhorn Flats) Farm Update DECEMBER 2011 The CWD infection rate was nearly 80%, the highest ever in a North American captive herd. RECOMMENDATION: That the Board approves the purchase of 80 acres of land for $465,000 for the Statewide Wildlife Habitat Program in Portage County and approve the restrictions on public use of the site.
Form 1100-001 (R 2/11) NATURAL RESOURCES BOARD AGENDA ITEM SUBJECT: Information Item: Almond Deer Farm Update FOR:
DECEMBER 2011 BOARD MEETING
TUESDAY TO BE PRESENTED BY TITLE: Tami Ryan, Wildlife Health Section Chief SUMMARY:
http://dnr.wi.gov/about/nrb/2011/december/12-11-2b2.pdf
http://web.archive.org/web/20140831060348/http://dnr.wi.gov/about/nrb/2011/december/12-11-2b2.pdf
https://datcp.wi.gov/Pages/Programs_Services/FarmRaisedDeer.aspx
https://datcp.wi.gov/Documents/FRDCWDWebData.pdf
https://dnr.wisconsin.gov/topic/wildlifehabitat/cwd.html
Colorado CWD TSE Prion
“The overall incidence of clinical CWD in white-tailed deer was 82% “
Epidemiology of Chronic Wasting Disease in Captive White-Tailed and Mule Deer
Michael W. Miller'* and Margaret A. Wildi Colorado Division of Wildlife, Wildlife Research Canter, 317 West Prospect Road, Fort Colins, Colorado 80526-2097. USA: ' Current address: National Park Service, Biologica Rosourco Mansacment Orvzion, 1201 Osk Ridae Drive. Suite 200. Fort Collina. Colorado 80525, USA: 2 Con responding author (emal: mke.miller@state.co.us)
The natural occurence of chroni. vasting discase (CWD) in a 1993 cohort of cap- tive white-tailed deer (Odocolleus cirginianus fforded the opportunity to describe epidemic tnamics in this species and to compare du namics with those seen in contemporary infected with CWD. The overall incidence clinkn CW'D in white-taled doer wis 82% (nine of 11) among individuals that survived Altected white-tailed deer diedot vere killed because of terminal CWD at age dynamics of CWD in captive white tailed deer vere similar to donamics in mule deer cohorte Incidence of clinical CWD 575 (4/7) among hand-raised (HR) and 67% (4/6) among dam-raised (DR) mule deer; affected HR mule deer succumbed at 64-86 mo of age (8-72) mo; SE-5 mo), and affected DR mule deer died at age 31-58 mo ({-41.3 mo; SE-6.1| Sustained horizontal transmission amics, but the original source of exposure could not he determied. Apparent dillerence in mean age at CWD-caused death among these cohorts may be attnibutable to dillerences in the timing or intensity of exposure to CWD. and these tactors aspear to be more axel lo influence epidemic dynamies than species dif. ferences. It follows that CWD epidemic dy namies in sympatric, free-ranging white-tuiled and mule der shanne habitats in westeri North American ranges also may be similar: Chronic washing discuse, en semiology, mule deer, Odocoileus hemionus, Odocolleus virginianus, prion, transmissible spongilorm encephalopathy, white-tailed deer.
Epidemics of chronie wasting disease (CWD), a prion disease of North Ameri- can cervids, were originally described in captive mule deer (Odocoileus hemionus) and elk (Cerous elaphus nelsoni) (Williams) and Young, 1980, 1982, 1992; Miller et al., 1998). The first epidemics were recog- nized in wildlife research facilities in Wyoming. Subsequent field investigations revealed cases of CWD in free-ranging cervids in these same areas (Williams and Young, 1992; Spraker et al., 1997; Miller •t al., 2000). Although the vast majority o free-ranging cases were diagnosed in mule deer and elk, cases of CWD also were en- countered in white-tailed deer (O. virgi- nianus). Because the prevalence of CWD in free-ranging white-tailed deer was re- markably high in some locations, the smaller number of cases was regarded as rellecting the relative scarcity of white- tailed deer in these areas rather than in- nate species resistance to CWD (Miller et al., 2000). The recent discovery of CWD in both free-ranging and captive white- tailed deer in the upper midwestern Unit- ed States (Williams et al., 2002; Joly et al. 2003) suggests that epidemics can arise in white-tailed deer populations in the ab- sence of sympatric mule deer or elk pop-alations.
The epidemic dynamics of CWD have not been described in white-tailed deer. This species was absent from affected re- search facilities during the 1960s-80s. when epidemics were first recognized and described in mule deer and elk. However a small captive white-tailed deer herd was established at the Colorado Division of Wildlife's (CDOW) Foothills Wildlife Re search Facility (FWRF; Fort Collins, Col- orado, USA; 4035'N,105°10'W) in 1993 for use in fertility control studies. The sub- sequent natural accurrence of CWD in this herd afforded the opportunity to ob- serve epidemic dynamies in captive white- tailed deer and compare them with those of contemporary cohorts of captive mule deer, which were also naturally infected with CWD.
The overall incidence of clinical CWD in white-tailed deer was 82% Species (cohort) CWD (cases/total) Incidence (%) Age at CWD death (mo)
https://www.sos.state.tx.us/texreg/pdf/backview/0411/0411adop.pdf
TUESDAY, FEBRUARY 25, 2025
TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update February 25, 2025
TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update
AUDIT SUBCOMMITTEE MEETING AGENDA February 25, 2025, 8:00 A.M
https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
OfficialCommissionMeetingBook423.pdf
http://web.archive.org/web/20250225154629/https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
snip...
Chronic Wasting Disease (CWD): There have been seven positive breeding facilities since January 1, 2024. Dr. Jessica Monday, TAHC State Epidemiologist, will give an update under Agenda Item #9.
https://chronic-wasting-disease.blogspot.com/2025/02/texas-animal-health-commission-423rd.html
http://web.archive.org/web/20250225154629/https://www.tahc.texas.gov/agency/meetings/OfficialCommissionMeetingBook423.pdf
Chronic Wasting Disease Detected in Kaufman County Deer Breeding Facility
March 10, 2025
Media Contact: TPWD News, Business Hours, 512-389-8030
News
AUSTIN – Texas Parks and Wildlife Department (TPWD) received confirmation of two cases of chronic wasting disease (CWD) in a Kaufman County deer breeding facility. This is the first CWD detection in a deer breeding facility in the county.
Two white-tailed deer – a 20-month-old male and an eight-month-old female — tested positive through ante-mortem testing conducted to meet CWD surveillance requirements prior to transferring deer from the registered deer breeding facility. Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) initially analyzed the samples, and the National Veterinary Services Laboratory in Iowa confirmed the CWD detection.
CWD has an incubation period that can span years, so the first indication of the disease in a herd is often found through surveillance testing rather than observed clinical signs. Permitted deer breeding facilities must test all mortalities within the facility and conduct ante-mortem testing on any deer prior to movement from the facility, in compliance with surveillance and testing requirements. This positive facility and its premises were placed under a quarantine by Texas Animal Health Commission (TAHC) to help prevent spread of disease from the facility. TPWD and TAHC will be working with the facility owner to develop a herd plan to address disease mitigation in the facility.
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 process continues, 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, regulations, and CWD best management practices for hunters and landowners, visit TPWD’s CWD page.
https://tpwd.texas.gov/newsmedia/releases/?req=20250310a
FRIDAY, JANUARY 10, 2025
TAHC Chronic Wasting Disease Detected in Brown County High-Fence Release Site
AUSTIN, TX – Texas Parks and Wildlife Department (TPWD) and Texas Animal Health Commission (TAHC) received confirmation of one case of chronic wasting disease (CWD) in a Brown County high fence ranch, marking the first confirmed detection in the county.
A three and a half-year-old female white-tailed deer tested positive through postmortem testing conducted to meet CWD surveillance requirements for a site epidemiologically traced to a CWD-positive facility. Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) initially analyzed the samples, and the National Veterinary Services Laboratory in Iowa confirmed the CWD detection.
The detection occurred on a ranch registered as a deer breeder release site and identified as having received deer from a CWD-positive breeding facility reported in 2024.
CWD has an incubation period that can span years, so the first indication of the disease in a herd is often found through surveillance testing rather than observed clinical signs. Testing hunter-harvested deer allows animal health officials to assess disease presence and was required as part of the quarantine issued for this property epidemiologically traced to a facility with a CWD-positive detection.
Landowners and hunters are encouraged to implement sound wildlife management practices, such as adequate deer harvest and management of healthy native habitat, to help mitigate disease impacts on the deer populations, especially in areas where CWD has been detected.
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 process continues, 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, regulations, and CWD best management practices for hunters and landowners, visit TPWD’s CWD page or TAHC’s CWD page.
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January 10, 2025
TAHC Chronic Wasting Disease Detected in Brown County High-Fence Release Site
https://www.tahc.texas.gov/news/2025/2025-01-10-CWD_BrownCo.pdf
Texas Kimble County Farm Chronic Wasting Disease CWD TSE Prion Approximate Herd Prevalence 12%
SUMMARY MINUTES OF THE 407th COMMISSION MEETING Texas Animal Health 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.
https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22
http://web.archive.org/web/20201017124040/https://www.tahc.texas.gov/agency/meetings/minutes/SummaryMinutes_CommMtg_2020-09-22.pdf
Wisconsin CWD
2025 CWD Wisconsin and Texas, and ramifications from the past, shall we…
Wisconsin DNR says CWD sinking deer herds in disease-endemic areas
PATRICK DURKIN Outdoors Columnist
CWD culprits
Snip…
“We can now say it’s not EHD (epizootic hemorrhagic disease), it’s not coyotes, it’s not bobcats, and it’s not earn-a-buck regulations from 15 years ago that are causing the herd declines we’re seeing,” said Dan Storm, the study’s chief researcher. “CWD is the cause, and we have solid evidence to back it up. This is what’s going on, and so let’s proceed with what to do about it.”
“We already did that and look how it went,” Storm said. “Before we lost earn-a-buck (in 2011), hunters dropped Iowa County’s deer herd below 20,000. After earn-a-buck, the herd took 7%, 10% and 12% annual increases until 2020. That herd should have kept growing, but it didn’t. CWD is pulling it down and boxing it in.”
The DNR’s annual post-hunt population estimates show Iowa County’s herd rose 51.3% from 16,900 in 2011 to 25,566, the 2018-2020 three-year average. The herd has since fallen 15.25% to 21,666, the 2021-2023 three-year average.
Bryan Richards, CWD project leader at the USDA’s National Wildlife Health Center in Madison, said backing off would backfire. “You won’t recover a population by letting CWD run its course,” Richards said. “When you try to stockpile deer by not shooting, you protect sick deer, too. Contamination worsens and the healthy proportion of the herd declines. Shooting removes sick deer from the herd sooner than CWD will. They’ll spread fewer prions over time, and you’ll probably shoot them before CWD reaches its worst stages for shedding prions.”
Storm put it this way: “The more CWD you have in your area, the more the herd will decline.” Which areas already exceed 29% infection rates for adult does? The latest DNR data from a year ago shows southeastern Richland County on the edge at 27%, northwestern Iowa County at 35%, and the Devil’s Lake area in eastern Sauk County at 34%.
Further, CWD testing of hunter-killed deer in autumn 2024 shows overall (bucks and does) detection rates at or above 29% in six townships (6-mile by 6-mile areas) in Columbia County, three townships in Dane County, eight townships in Iowa County, 11 townships in Richland County, and 15 townships in Sauk County.
How low will deer populations drop where CWD is endemic? Storm said CWD won’t exterminate deer, but no one can predict how it will affect specific valleys, woodlands or watersheds. CWD has spread at varying rates in different Wisconsin habitats, and appears to have leveled off at high infection rates in some areas while still rising and spreading in others.
The disease has so far been verified in wild deer in 48 of Wisconsin’s 72 counties, even though testing has been totally voluntary for years. During the 2024 hunting season, 1,755 more deer tested positive for CWD across the state, a record 10.4% detection rate despite the least amount of samples (16,939) volunteered since 2017. Richland County hunters provided the most samples, 1,335, in 2024, and 444 (33.4%) had CWD.
https://www.antigojournal.com/sports/outdoors/durkin-wisconsin-dnr-says-cwd-sinking-deer-herds-in-disease-endemic-areas/article_cb73b5ca-dd9e-11ef-853c-d3fb206ddf8c.html
18% of mule deer in northeastern Montana have deadly chronic wasting disease “In the 2024-25 hunting FWP submitted 9,066 samples for chronic wasting disease testing – the largest number of CWD samples ever collected in a single year. More than 1,100 of these samples were collected by hunters. Of those samples, 335 tested positive for the disease, including 202 white-tailed deer, 127 mule deer and six elk.”
https://billingsgazette.com/outdoors/article_de5278b8-f2e1-11ef-b479-cf42652717a4.html
Wisconsin Caltive CWD Positives update 1/30/2024
HOLY SMOKES Wisconsin Captive CWD Positives update January 2024
Chronic Wasting Disease Positives in Farm-raised Deer Revised: 1/30/2024
https://datcp.wi.gov/Documents/WI%20CWD%20Positives1.pdf
https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf
Wisconsin CWD year 2024
DNR Zone # Sampled # Analyzed Positive for CWD
Central Farmland Zone 7100 7100 175
Central Forest Zone 628 628 18
Northern Forest Zone 1850 1850 5
Southern Farmland Zone 7494 7483 1573
Unknown Zone 31 29 0
Totals: 17103 17090 1771
https://apps.dnr.wi.gov/cwd/summary/YearZone/2024
https://dnr.wisconsin.gov/topic/WildlifeHabitat/registersample
https://dnr.wisconsin.gov/topic/WildlifeHabitat/results
https://datcp.wi.gov/Pages/Programs_Services/FarmRaisedDeer.aspx
https://datcp.wi.gov/Pages/Programs_Services/FRDHerdStatusPrograms.aspx
https://www.aphis.usda.gov/sites/default/files/status-of-captive-herds.pdf
Iowa 79.8 percent of the deer tested positive CWD and Wisconsin Buckhorn Flats Nearly 80% CWD positive
For Immediate Release
Thursday, October 2, 2014 Dustin Vande Hoef 515/281-3375 or 515/326-1616 (cell) or Dustin.VandeHoef@IowaAgriculture.gov
TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE RELEASED 79.8 percent of the deer tested positive for the disease
DES MOINES – The Iowa Department of Agriculture and Land Stewardship today announced that the test results from the depopulation of a quarantined captive deer herd in north-central Iowa showed that 284 of the 356 deer, or 79.8% of the herd, tested positive for Chronic Wasting Disease (CWD). The owners of the quarantined herd have entered into a fence maintenance agreement with the Iowa Department of Agriculture and Land Stewardship, which requires the owners to maintain the 8’ foot perimeter fence around the herd premises for five years after the depopulation was complete and the premises had been cleaned and disinfected
CWD is a progressive, fatal, degenerative neurological disease of farmed and free-ranging deer, elk, and moose. There is no known treatment or vaccine for CWD. CWD is not a disease that affects humans.
On July 18, 2012, USDA Animal and Plant Health Inspection Service’s (APHIS) National Veterinary Services Lab in Ames, IA confirmed that a male white tail deer harvested from a hunting preserve in southeast IA was positive for CWD. An investigation revealed that this animal had just been introduced into the hunting preserve from the above-referenced captive deer herd in north-central Iowa.
The captive deer herd was immediately quarantined to prevent the spread of CWD. The herd has remained in quarantine until its depopulation on August 25 to 27, 2014.
The Iowa Department of Agriculture and Land Stewardship participated in a joint operation to depopulate the infected herd with USDA Veterinary Services, which was the lead agency, and USDA Wildlife Services.
Federal indemnity funding became available in 2014. USDA APHIS appraised the captive deer herd of 376 animals at that time, which was before depopulation and testing, at $1,354,250. At that time a herd plan was developed with the owners and officials from USDA and the Iowa Department of Agriculture and Land Stewardship.
Once the depopulation was complete and the premises had been cleaned and disinfected, indemnity of $917,100.00 from the USDA has been or will be paid to the owners as compensation for the 356 captive deer depopulated.
The Iowa Department of Agriculture and Land Stewardship operates a voluntary CWD program for farms that sell live animals. Currently 145 Iowa farms participate in the voluntary program. The above-referenced captive deer facility left the voluntary CWD program prior to the discovery of the disease as they had stopped selling live animals. All deer harvested in a hunting preserve must be tested for CWD.
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https://www.iowaagriculture.gov/press/2014press/press10022014.asp
http://web.archive.org/web/20141006172620/https://www.iowaagriculture.gov/press/2014press/press10022014.asp
Wisconsin Buckhorn Flats CWD
SUBJECT: Almond Deer Farm Update
The first case of Chronic Wasting Disease (CWD) among Wisconsin's farm-raised deer occurred in a white-tailed deer buck shot by a hunter at the property (formerly known as Buckhorn Flats) in September 2002. This situation prompted the eventual depopulation of the entire farm.
The deer, a mix of does and yearlings, were destroyed on January 17, 2006- 4 years later- by U.S. Department of Agriculture shooters under a USDA agreement with the farm owner.
Sixty of the 76 animals tested positive for CWD. The 76 deer constituted the breeding herd in the breeding facility on the farm. The property also had a hunting preserve until 2005. Four deer, two does and two fawns, the only deer remaining in the former preserve, were killed and tested as well. CWD was not detected in those animals.
The total number of deer to test positive from this farm from the initial discovery to final depopulation is 82. The nearly 80% prevalence rate discovered on Buckhorn Flats is the highest prevalence recorded in any captive cervid operation in North America.
Tuesday, December 20, 2011
Chronic Wasting Disease CWD WISCONSIN Almond Deer
(Buckhorn Flats) Farm Update DECEMBER 2011 The CWD infection rate was nearly 80%, the highest ever in a North American captive herd. RECOMMENDATION: That the Board approves the purchase of 80 acres of land for $465,000 for the Statewide Wildlife Habitat Program in Portage County and approve the restrictions on public use of the site.
Form 1100-001 (R 2/11) NATURAL RESOURCES BOARD AGENDA ITEM SUBJECT: Information Item: Almond Deer Farm Update FOR:
DECEMBER 2011 BOARD MEETING
TUESDAY TO BE PRESENTED BY TITLE: Tami Ryan, Wildlife Health Section Chief SUMMARY:
http://dnr.wi.gov/about/nrb/2011/december/12-11-2b2.pdf
http://web.archive.org/web/20140831060348/http://dnr.wi.gov/about/nrb/2011/december/12-11-2b2.pdf
https://datcp.wi.gov/Pages/Programs_Services/FarmRaisedDeer.aspx
https://datcp.wi.gov/Documents/FRDCWDWebData.pdf
https://dnr.wisconsin.gov/topic/wildlifehabitat/cwd.html
Colorado CWD TSE Prion
“The overall incidence of clinical CWD in white-tailed deer was 82% “
Epidemiology of Chronic Wasting Disease in Captive White-Tailed and Mule Deer
Michael W. Miller'* and Margaret A. Wildi Colorado Division of Wildlife, Wildlife Research Canter, 317 West Prospect Road, Fort Colins, Colorado 80526-2097. USA: ' Current address: National Park Service, Biologica Rosourco Mansacment Orvzion, 1201 Osk Ridae Drive. Suite 200. Fort Collina. Colorado 80525, USA: 2 Con responding author (emal: mke.miller@state.co.us)
The natural occurence of chroni. vasting discase (CWD) in a 1993 cohort of cap- tive white-tailed deer (Odocolleus cirginianus fforded the opportunity to describe epidemic tnamics in this species and to compare du namics with those seen in contemporary infected with CWD. The overall incidence clinkn CW'D in white-taled doer wis 82% (nine of 11) among individuals that survived Altected white-tailed deer diedot vere killed because of terminal CWD at age dynamics of CWD in captive white tailed deer vere similar to donamics in mule deer cohorte Incidence of clinical CWD 575 (4/7) among hand-raised (HR) and 67% (4/6) among dam-raised (DR) mule deer; affected HR mule deer succumbed at 64-86 mo of age (8-72) mo; SE-5 mo), and affected DR mule deer died at age 31-58 mo ({-41.3 mo; SE-6.1| Sustained horizontal transmission amics, but the original source of exposure could not he determied. Apparent dillerence in mean age at CWD-caused death among these cohorts may be attnibutable to dillerences in the timing or intensity of exposure to CWD. and these tactors aspear to be more axel lo influence epidemic dynamies than species dif. ferences. It follows that CWD epidemic dy namies in sympatric, free-ranging white-tuiled and mule der shanne habitats in westeri North American ranges also may be similar: Chronic washing discuse, en semiology, mule deer, Odocoileus hemionus, Odocolleus virginianus, prion, transmissible spongilorm encephalopathy, white-tailed deer.
Epidemics of chronie wasting disease (CWD), a prion disease of North Ameri- can cervids, were originally described in captive mule deer (Odocoileus hemionus) and elk (Cerous elaphus nelsoni) (Williams) and Young, 1980, 1982, 1992; Miller et al., 1998). The first epidemics were recog- nized in wildlife research facilities in Wyoming. Subsequent field investigations revealed cases of CWD in free-ranging cervids in these same areas (Williams and Young, 1992; Spraker et al., 1997; Miller •t al., 2000). Although the vast majority o free-ranging cases were diagnosed in mule deer and elk, cases of CWD also were en- countered in white-tailed deer (O. virgi- nianus). Because the prevalence of CWD in free-ranging white-tailed deer was re- markably high in some locations, the smaller number of cases was regarded as rellecting the relative scarcity of white- tailed deer in these areas rather than in- nate species resistance to CWD (Miller et al., 2000). The recent discovery of CWD in both free-ranging and captive white- tailed deer in the upper midwestern Unit- ed States (Williams et al., 2002; Joly et al. 2003) suggests that epidemics can arise in white-tailed deer populations in the ab- sence of sympatric mule deer or elk pop-alations.
The epidemic dynamics of CWD have not been described in white-tailed deer. This species was absent from affected re- search facilities during the 1960s-80s. when epidemics were first recognized and described in mule deer and elk. However a small captive white-tailed deer herd was established at the Colorado Division of Wildlife's (CDOW) Foothills Wildlife Re search Facility (FWRF; Fort Collins, Col- orado, USA; 4035'N,105°10'W) in 1993 for use in fertility control studies. The sub- sequent natural accurrence of CWD in this herd afforded the opportunity to ob- serve epidemic dynamies in captive white- tailed deer and compare them with those of contemporary cohorts of captive mule deer, which were also naturally infected with CWD.
The overall incidence of clinical CWD in white-tailed deer was 82% Species (cohort) CWD (cases/total) Incidence (%) Age at CWD death (mo)
https://cpw.state.co.us/Documents/Hunting/BigGame/CWD/PDF/ResearchArticles/JWDEpiCWD.pdf
http://web.archive.org/web/20150908134715/https://cpw.state.co.us/Documents/Hunting/BigGame/CWD/PDF/ResearchArticles/JWDEpiCWD.pdf
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“CWD spreads among wild populations at a relatively slow rate, limited by the natural home range and dispersed nature of wild animals.”
NOW HOLD YOUR HORSES, Chronic Wasting Disease CWD of Cervid can spread rather swiftly, traveling around 50 MPH, from the back of truck and trailer, and Here in Texas, we call it ‘Trucking CWD’…terry
Preventive Veterinary Medicine Volume 234, January 2025, 106385
Use of biosecurity practices to prevent chronic wasting disease in Minnesota cervid herds
Vehicles or trailers that entered the farm were used to transport other live cervids, cervid carcasses, or cervid body parts in past 3 years in 64.3 % (95 % CI 46.3–82.3) of larger elk/reindeer herds compared to 13.6 % (95 % CI 4.7–22.4) of smaller deer herds.
Snip…
Identifying the exact pathway of initial CWD transmission to cervid herds is often not possible, in part due to many potential pathways of transmission for the infection, including both direct and indirect contact with infected farmed or wild cervids (Kincheloe et al., 2021). That study identified that transmissions from infected farmed cervids may occur from direct contact with the movement of cervids from one herd to another and from indirect contact with the sharing of equipment, vehicles, clothing, reproductive equipment, and potentially through semen or embryos.
https://www.sciencedirect.com/science/article/abs/pii/S016758772400271X
SCIENCE AND TECHNOLOGY, RESEARCH
All-out approach needed to curb chronic wasting disease ‘hotspots’ on farms, study suggests Removing access to some but not all food attractants could increase the risk of transmission of the fatal disease among mule deer.
APRIL 23, 2025 BY ADRIANNA
Reducing the number of accessible food “hotspots” like stored crops, hay bales and grain bins that attract wild deer to farms or fields could inadvertently make the spread of chronic wasting disease worse, according to a recent study published in Ecology and Evolution. https://pmc.ncbi.nlm.nih.gov/articles/PMC11840243/
The finding suggests a more comprehensive strategy is needed to help farmers and wildlife managers protect deer by controlling the spread of the fatal disease, explains Kelsey Gritter, who led the research as part of her master’s thesis in ecology. If they choose to remove these artificial attractants by making them inaccessible to the deer, they likely need to eliminate all of them rather than just a portion for the approach to be effective.
Chronic wasting disease, or CWD, affects the central nervous system of cervids such as deer, elk and moose. Alberta created an ongoing surveillance program in 1998 to track prevalence, which continues to rise in many areas, with over 75% infection in mule deer males in some local areas where CWD has been present for many years.
It is spread through direct transmission between animals, as well as environmentally as the deer shed prions (misfolded proteins) through saliva, urine and feces, says Gritter. Artificial attractants become hotspots for both forms of disease transmission.
“They cause the deer to congregate and be present in unnaturally high numbers in one location and can affect CWD transmission,” says Gritter.
These artificial attractants could encourage deer to leave their home range (the area they typically move within), which would increase the likelihood of deer from different groups infecting one another.
“There’s a lot of ways that artificial attractants can cause problems when it comes to disease spread.”
For the study, Gritter and her collaborators wanted to examine the impact of the density of artificial attractants in a particular area as well as their configuration. “Density is important because if we’re trying to reduce the impact of these sites, the number of sites is one of the things we’re able to target,” says Gritter. “And configuration is important because there may be better or worse arrangements of these sites that cause more or less contact, so when creating management strategies, we can aim to achieve configurations that are better.”
The researchers gathered behavioural data from tagged mule deer, including group size, the home range they typically roam within, and the habitat and landscape characteristics they’re naturally drawn to. The researchers looked at data taken every two hours, which also provided information on how far the deer tended to travel and how much they typically deviated from their path.
“When we have the information about the landscape and their general movement patterns, we can use that to sort of simulate their movement,” says Gritter.
With the data in hand, the researchers created a computer model to simulate different scenarios: removing all attractants at a particular location, removing a few at random, or removing them based on proximity to the deer’s preferred habitat.
They found that making some but not all attractants inaccessible to deer actually increased contact rates, particularly between different groups of deer, because the same number of deer were then gathering around the fewer remaining sites. Removing attractants near their preferred habitat, such as areas with a lot of trees and shrubs, encouraged even higher rates of contact. The only effective strategy was to remove all attractants from a particular farm or field.
While the computer simulations looked at a scenario with moderate mule deer populations, Gritter notes that further research is needed to understand what effect deer population size may have on results.
https://www.ualberta.ca/en/folio/2025/04/all-out-approach-needed-to-curb-cwd-hotspots-on-farms.html
Chronic wasting disease prions on deer feeders and wildlife visitation to deer feeding areas
Miranda H. J. Huang, Steve Demarais, Marc D. Schwabenlander, Bronson K. Strickland, Kurt C. VerCauteren, William T. McKinley, Gage Rowden, Corina C. Valencia Tibbitts … See all authors
First published: 10 February 2025
https://doi.org/10.1002/jwmg.70000
Abstract
Eliminating supplemental feeding is a common regulatory action within chronic wasting disease (CWD) management zones. These regulations target the potential for increased animal-animal contact and environmental contamination with CWD prions. Prions, the causative agent of CWD, have been detected on feeder surfaces in CWD-positive, captive deer facilities but not among free-ranging populations, and information on the relative risk of transmission at anthropogenic and natural food sources is limited. In this study, we established and maintained 13 gravity feeders from September 2022 to March 2023 in a CWD zone in northern Mississippi, USA (apparent prevalence ~30%). We set up feeders up in 3 ways: no exclusion (deer feeders, n = 7), exclusion of deer using fencing with holes cut at the ground-level to permit smaller wildlife to enter (raccoon feeders, n = 3), and environmental control feeders, which were fully fenced and not filled with feed (control feeders, n = 3). We swabbed feeder spouts at setup and at 4 intervals approximately 6 weeks apart to test for prion contamination via real-time quaking-induced conversion (RT-QuIC). We detected prions 12 weeks after setup on all deer and raccoon feeders. We compared relative transmission risk using camera traps at these feeders, 6 agronomic plantings for wildlife forage (i.e., food plots), and 7 oak mast trees. Weekly visitation rate by white-tailed deer (Odocoileus virginianus; hereafter: deer) differed (P = 0.02) among deer feeders (median = 24.5 deer/week, range = 15.6–65.7), food plots (median = 12.7, range = 3.8–24.7), and mast trees (median = 2.0, range = 0.4–5.1). Contact rates between individual deer also differed between site types (P < 0.01): deer feeders (median = 2.1 deer-to-deer contacts/week, range = 0–10.1), food plots (median = 0.1, range = 0–4.0), and mast trees (median = 0, range = 0–0.3). Raccoons also visited feeders at greater rates than food plots and mast trees (P < 0.04). Finally, we swabbed 19 feeders in 2 areas where CWD was newly detected, finding prion contamination on swabs from 4 feeders. We show that deer feeders in free-ranging populations with high CWD prevalence become contaminated with CWD prions quickly, becoming a potential site of exposure of deer to CWD prions. Our results also demonstrate the ability to find evidence of prion contamination on deer feeders, even in areas where CWD is newly detected.
Snip…
We found that supplemental feeding increased the risk of exposure to CWD prions due to contamination of feeders, increased deer visitation, and increased deer-to-deer contact.
The 12-fold increase in deer visitation to feeders compared to mast trees and 2-fold increase compared to food plots demonstrates increased risk for direct disease spread.
https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.70000
Chronic wasting disease (CWD) prion detection in environmental and biological samples from a taxidermy site and nursing facility, and instruments used in surveillance activities
Paulina Soto a b , Nancy Ho a , Mitch Lockwood c , Austin Stolte c , J. Hunter Reed c , Rodrigo Morales a b
a Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
b Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, Chile
c Texas Parks and Wildlife Department (TPWD), Kerrville, TX, United States of America
Received 20 September 2024, Revised 27 February 2025, Accepted 31 March 2025, Available online 9 April 2025, Version of Record 9 April 2025.
Cite https://doi.org/10.1016/j.scitotenv.2025.179318
Highlights
• CWD prions were identified in a taxidermy and deer nursing facility.
• Contaminated samples included waters, soils, dermestid beetles, domestic flies and a dumpster.
• Surgical instruments used to collect deer samples can get contaminated with CWD prions.
• Some of the infectious particles are readily released from surgical instruments when washed.
• Our results suggest that taxidermy practices actively contribute in the spreading of CWD.
Abstract
Chronic wasting disease (CWD) is a transmissible prionopathy affecting free-ranging and captive cervids. CWD is thought to spread through both direct and indirect transmission mechanisms. Along this line, human activities have not been thoroughly explored for their potential to spread this disease. One area of concern involves taxidermy procedures and surveillance activities as handled animals or carcasses are of unknown CWD statuses. Worrisomely, taxidermy facilities can act as foci of prion infectivity if appropriate biosecurity practices are not implemented. In this study, we evaluated the presence of infectious prions in a taxidermy facility that was possibly exposed to CWD prions. To determine this, we collected biological and environmental specimens from this site and screened them using the protein misfolding cyclic amplification (PMCA) technique. Additionally, we swabbed different surfaces possibly exposed to CWD-infected animals or carcasses. We report the presence of prions in i) waters used to digest tissues from deer carcasses, ii) soils that were in contact with the previously mentioned waters, iii) dermestid beetles used to clean skulls, iv) other insects found in the beetle shed, and iv) dumpsters where animal carcasses were disposed. Additionally, we report that surgical materials used in surveillance practices may also hold CWD prions, even after being washed with aqueous solutions. All these results suggest that CWD prions may be disseminated due to human practices and that protocols should be established to decontaminate potentially contaminated materials.
Introduction
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects multiple cervid species, including mule deer, white-tailed deer, elk, reindeer, and moose, among others (Escobar et al., 2020). CWD is widely distributed in the United States and Canada in captive and free-ranging cervids. CWD is characterized by long incubation periods, followed by a relatively short clinical phase (Rivera et al., 2019; Williams, 2005). CWD is fatal in all cases when animals are clinical, and to date, there is no feasible treatment for curing either CWD or any other prion disease (Haley and Hoover, 2015). Unfortunately, CWD is rapidly expanding in both number of animals affected and geographical areas (Bartz et al., 2024; National Wildlife Health Center, 2025). Considering this, efficient containment and diagnostic testing strategies are urgently needed.
CWD can spread within animal populations with relative ease (Otero et al., 2021). The propagation of this disease is thought to be more efficient in captive animals considering the higher animal densities found in these environments (Mathiason et al., 2009; Rivera et al., 2019; Bartelt-Hunt and Bartz, 2017; Zabel and Ortega, 2017). Nevertheless, CWD transmission is still highly efficient in free-ranging cervid populations. CWD transmission is thought to occur mostly through direct animal contacts, or indirectly through the exposure of naïve animals to contaminated environments (Denkers et al., 2013; Escobar et al., 2020; Haley et al., 2011; Mathiason et al., 2009; Miller Michael et al., 2004; Soto et al., 2024). Environmental components, including inert materials and living organisms, are thought to play relevant roles in the spread of CWD (Escobar et al., 2020; Jacobson et al., 2010a; Pritzkow et al., 2018). Different studies have shown that infectious prions can enter the environment through decaying carcasses from diseased animals (Soto et al., 2023), gestational tissues released during parturition (Bravo-Risi et al., 2021), saliva (Haley et al., 2011), and excreta (Bravo-Risi et al., 2023). Once released, prions can bind to soil and other natural and manmade components (Johnson et al., 2006; Smith et al., 2011) and become available to susceptible animals. Other organisms, including plants, predators, scavengers, parasites, insects, and annelids may also participate in these processes by interacting with contaminated environmental components or animal tissues (Carlson et al., 2023; Fischer et al., 2013; Inzalaco et al., 2023; Pritzkow et al., 2015; Soto et al., 2024). Overall, multiple components and processes are involved in CWD prion transmission and dissemination. However, most of them are understudied and/or assayed in laboratory-controlled conditions. As consequence, the specific contribution of each process/element in CWD environmental contamination is contentious.
An essential factor to consider in the spreading of CWD prions includes human activities (Mori et al., 2024). Along this line, regulatory agencies already implemented or are currently considering regulations in several of these activities including containment, animal processing, movement of animals, disposal of carcasses, and breeding practices, among others (Mateus-Pinilla et al., 2013; Mysterud and Edmunds, 2019). Although most of these practices have a potential for CWD transmission, their overall importance in CWD epidemiology is understudied. One example of this involves taxidermy procedures. Deer are regarded as one of the most popular game animals, generating a high economic output and involving various activities including deer breeding, taxidermy, meat processing, and others (Arnot et al., 2009; Bishop, 2004) (https://nri.tamu.edu/media/3968/economic-values-of-white-tailed-deer-in-texas-2022-survey-part-i.pdf). Hunters active in areas with reported CWD cases are requested to follow state, wildlife and public health recommendations (Carlson et al., 2018). In general, all agencies strongly suggest CWD animal testing before processing. Many hunters process game at private facilities and, because of no statutory authority or lack of awareness, CWD-relevant guidelines or rules may not exist for meat processing and taxidermy facilities despite their capacity to transmit CWD. Specifically, the movement of carcasses or carcasses parts from areas with a high CWD incidence to areas with little or no incidence may facilitate CWD introduction and spread. In addition, it should be considered that inappropriate disposal of carcasses and animal products may also contribute to the dissemination of this disease (Angers et al., 2009; Benestad et al., 2016). Considering the above-mentioned scenarios, proper surveillance of CWD and management of activities involving potentially infected animals and animal-derived products might help to contain it. If left unchecked, there could be profound negative impacts on human health and wildlife conservation.
In this study, we evaluated the presence of CWD prions in a taxidermy facility where deer heads are processed to prepare skull mounts. Analyses were made using the protein misfolding cyclic amplification (PMCA) technique in various biological and environmental samples. In addition, we also tested the persistence of CWD prions in surgical materials used in surveillance procedures. Our results show, for the first time, CWD-prion detection in a potentially exposed taxidermy facility. In addition, we also tested the persistence of CWD prions in surgical materials used in surveillance procedures. This information has important implications on several fronts of CWD research including environmental spreading, human-related practices, and exposure of humans to infectious animal prions.
Section snippets
Samples
The samples were collected from a taxidermy and free-ranging deer rehabilitation facility located on the same property in Val Verde County, Texas. Texas Parks and Wildlife Department (TPWD) staff were initially notified of a CWD clinical suspect on this property; this animal was ultimately euthanized and confirmed positive for CWD by the National Veterinary Services Laboratory on January 5th, 2020. Samples were collected from different areas on this property where deer heads were processed to Screening of CWD prions in environmental and processing elements from a taxidermy facility
The European mount technique is a widely utilized taxidermy practice aiming to produce a skull of an animal that is free of tissue. The first critical step in making a European mount is removing the flesh from the animal's head. This is achieved by removing the majority of the external flesh, eyeballs, ears, and the brain. Then, the de-meated skull is subjected to a maceration process using bacteria. The purpose of this step is to soften and degrade any remaining tissue on the skull. This Discussion
CWD continues expanding in distribution and prevalence in North America. Hence, an essential factor in limiting the spread of this disease is to monitor and contain infectivity foci. This has proven to be difficult considering the limited diagnostic tools available to effectively identify the CWD infectious agent (prions). Identifying and mitigating the negative role that anthropogenic activities have in promoting CWD transmission is an essential step in developing a prevention strategy. The Conclusion
In summary, the information provided in this report demonstrate how anthropogenic activities, specifically taxidermy practices, animal processing, and rehabilitation of CWD susceptible species, may facilitate CWD transmission through the environmental dissemination of CWD prions. This study, along with future research efforts characterizing the overall level of infectivity, provides relevant information on managing CWD and to control its rapid geographic expansion. …
https://www.sciencedirect.com/science/article/abs/pii/S0048969725009544
THE CWD 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
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
http://www.pnas.org/content/97/7/3418.full
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2493038/
March 13, 2025
Prion Partitioning and Persistence in Environmental Waters
https://pubs.acs.org/doi/epdf/10.1021/acs.est.4c11497?ref=article_openPDF
Prions in Waterways
https://vimeo.com/898941380?fbclid=IwAR3Di7tLuU-iagCetdt4-CVPrOPQQrv037QS1Uxz0tX3z7BuvPeYlwIp7IY
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
http://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
https://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
https://link.springer.com/content/pdf/10.1007%2Fs00705-019-04154-8.pdf
In summary, CWD prions are efficiently transmitted to WTD via aerosolization using a delivered dose substantially lower than previously reported by the oral route. Our results provide further evidence that prions delivered to the nasal passages are sufficient to transmit CWD and allow the inference that aerosolization may facilitate the transmission of prions in general.
https://journals.asm.org/doi/10.1128/jvi.02852-12
In summary, our results establish aerosols as a surprisingly efficient modality of prion transmission. This novel pathway of prion transmission is not only conceptually relevant for the field of prion research, but also highlights a hitherto unappreciated risk factor for laboratory personnel and personnel of the meat processing industry. In the light of these findings, it may be appropriate to revise current prion-related biosafety guidelines and health standards in diagnostic and scientific laboratories being potentially confronted with prion infected materials. While we did not investigate whether production of prion aerosols in nature suffices to cause horizontal prion transmission, the finding of prions in biological fluids such as saliva, urine and blood suggests that it may be worth testing this possibility in future studies.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1001257
Mineral licks as environmental reservoirs of chronic wasting disease prions
Ian H. Plummer,Chad J. Johnson,Alexandra R. Chesney,Joel A. Pedersen ,Michael D. Samuel
Abstract
Chronic wasting disease (CWD) is a fatal neurodegenerative disease of deer, elk, moose, and reindeer (cervids) caused by misfolded prion proteins. The disease has been reported across North America and recently discovered in northern Europe. Transmission of CWD in wild cervid populations can occur through environmental routes, but limited ability to detect prions in environmental samples has prevented the identification of potential transmission “hot spots”. We establish widespread CWD prion contamination of mineral licks used by free-ranging cervids in an enzootic area in Wisconsin, USA. We show mineral licks can serve as reservoirs of CWD prions and thus facilitate disease transmission. Furthermore, mineral licks attract livestock and other wildlife that also obtain mineral nutrients via soil and water consumption. Exposure to CWD prions at mineral licks provides potential for cross-species transmission to wildlife, domestic animals, and humans. Managing deer use of mineral licks warrants further consideration to help control outbreaks of CWD.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0196745#sec008
December 2014, Volume 36, Issue 6, pp 1049–1061 | Cite as
Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer
Authors Authors and affiliations Michael J. LavelleEmail authorGregory E. PhillipsJustin W. FischerPatrick W. BurkeNathan W. SewardRandal S. StahlTracy A. NicholsBruce A. WunderKurt C. VerCauteren 1. 2. 3. 4.
Article First Online: 08 April 2014
Abstract
Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids. Keywords Cervus elaphus Chronic wasting disease Elk Geophagy Mineral lick Mule deer Odocoileus hemionus
https://rd.springer.com/article/10.1007/s10653-014-9600-0
Elk and Deer Use of Mineral Licks: Implications for Disease Transmission
Kurt C. VerCauteren1*, Michael J. Lavelle1, Gregory E. Phillips1, Justin W.. Fischer1, and Randal S. Stahl1 1United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO 80521-2154, USA *Cooresponding author e-mail: kurt.c.vercauteren@aphis.usda.gov
North American cervids require and actively seek out minerals to satisfy physiological requirements. Minerals required by free-ranging cervids exist within natural and artificial mineral licks that commonly serve as focal sites for cervids. Ingestion of soils contaminated with the agent that causes chronic wasting disease (CWD) may result in risk of contracting CWD.
Our objective was to evaluate the extent and nature of use of mineral licks by CWD-susceptible cervid species. We used animal-activated cameras to monitor use of 18 mineral licks between 1 June and 16 October 2006 in Rocky Mountain National Park, north-central Colorado.. We also assessed mineral concentrations at mineral licks to evaluate correlations between visitation rates and site-specific characteristics. We collected > 400,000 images of which 991 included elk, 293 included deer, and 6 included moose.
We documented elk and deer participating in a variety of potentially risky behaviors (e.g., ingesting soil, ingesting water, defecating, urinating) while at mineral licks.
Results from the mineral analyses combined with camera data revealed that visitation was highest at sodium-rich mineral licks.
Mineral licks may play a role in disease transmission by acting as sites of increased interaction as well as reservoirs for deposition, accumulation, and ingestion of disease agents.
https://int-cwd-sympo.org/wp-content/uploads/2023/06/final-agenda-with-abstracts.pdf
DEFRA
In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.
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In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
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36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.
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The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).
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In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.
snip.....
In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible...
UFor deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.
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Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.
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https://web.archive.org/web/20170404125557/http://webarchive.nationalarchives.gov.uk/20130822084033/http://www.defra.gov.uk/animal-diseases/files/qra_chronic-wasting-disease-121029.pdf
Title: Horizontal transmission of chronic wasting disease in reindeer
Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/29/2016 Publication Date: 12/1/2016
Citation: Moore, S., Kunkle, R., Greenlee, M., Nicholson, E., Richt, J., Hamir, A., Waters, W., Greenlee, J. 2016. Horizontal transmission of chronic wasting disease in reindeer.
Emerging Infectious Diseases. 22(12):2142-2145. doi:10.3201/eid2212.160635.
Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.
Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI). We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=328261
Conclusions
Potential sources of infectivity for direct contact animals include urine, feces, and saliva from their CWDwtd-challenged pen-mates, as has been shown for CWD-affected white-tailed deer (6,8,9). Pinpointing the source of infectivity in the indirect contact group is more difficult. Infectious prions can travel at least 30 m in airborne particulate (10), but because the negative control reindeer in the pen adjacent to the indirect contact reindeer did not become positive, a more direct route of transmission is likely in this case. Penning, feeding, and watering protocols were designed to prevent exposure of negative control and indirect contact reindeer to potential infectivity on feed and water buckets, bedding, or fencing (6,11). However, reindeer might have had access to bedding from adjacent pens that had spread into the central alleyway.
During the 5-year course of this study, reindeer were moved between pens several times to maintain an optimal number of animals per pen (Technical Appendix Figure 1). Prolonged persistence of prion infectivity in the natural environment has been documented for both CWD (2 years [5]) and scrapie (up to 16 years [12]). In addition, thorough cleaning and disinfection might not be sufficient to remove all infectivity from the environment, leading to persistence of infectivity under experimental housing conditions (13).
In reindeer challenged orally with the agent of CWD, the SS138 genotype (serine/serine at PRNPcodon 138) has been associated with susceptibility to disease and the NS138 (asparagine/serine) genotype with resistance (1). In the study we report, disease developed in reindeer with the NS138 genotype after intracranial inoculation, although the extent of lymphoreticular system involvement was significantly lower than in NN138 and SS138 reindeer. The potential association of the NN138 polymorphism with shorter survival times is interesting. However, as with all potential genotype versus phenotype interactions, care should be taken not to over-interpret these results given the small group sizes and the large number of PRNPgenotype groups in this study.
Our results demonstrate that reindeer are susceptible to the agent of CWD from white-tailed deer, mule deer, and elk sources after intracranial inoculation. Furthermore, naive reindeer are susceptible to the agent of CWD after direct and indirect exposure to CWD-infected reindeer, suggesting a high potential for horizontal transmission of CWD within and between farmed and free-ranging reindeer (and caribou) populations.
https://wwwnc.cdc.gov/eid/article/22/12/16-0635_article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5189146/
Rapid recontamination of a farm building occurs after attempted prion removal
First published: 19 January 2019 https://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 scrapie positive 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.
https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
https://pubmed.ncbi.nlm.nih.gov/30602491/
Front. Vet. Sci., 14 September 2015 | https://doi.org/10.3389/fvets.2015.00032
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
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.
http://journal.frontiersin.org/article/10.3389/fvets.2015.00032/full
"Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation."
15 YEARS!
Detection of prions in soils contaminated by multiple routes
Results: We are able to detect prion seeding activity at multiple types of environmental hotspots, including carcass sites, contaminated captive facilities, and scrapes (i.e. urine and saliva). Differences in relative prion concentration vary depending on the nature and source of the contamination. Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation.
Conclusions: Detection of prions in the environment is of the utmost importance for controlling chronic wasting disease spread. Here, we have demonstrated a viable method for detection of prions in complex environmental matrices. However, it is quite likely that this method underestimates the total infectious prion load in a contaminated sample, due to incomplete recovery of infectious prions. Further refinements are necessary for accurate quantification of prions in such samples, and to account for the intrinsic heterogeneities found in the broader environment.
Funded by: Wisconsin Department of Natural Resources
Prion 2023 Abstracts
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
Artificial mineral sites that pre-date endemic chronic wasting disease become prion hotspots
The detection of PrPCWD in soils at attractant sites within an endemic CWD zone significantly advances our understanding of environmental PrPCWD accumulation dynamics, providing valuable information for advancing adaptive CWD management approaches.
https://int-cwd-sympo.org/wp-content/uploads/2023/06/final-agenda-with-abstracts.pdf
Detection of chronic wasting disease prions in the farm soil of the Republic of Korea
Here, we show that prion seeding activity was detected in extracts from farm soil following 4 years of incubation with CWD-infected brain homogenate.
https://journals.asm.org/doi/10.1128/msphere.00866-24
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
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.
Prion 2022 Conference abstracts: pushing the boundaries
https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
***> 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
https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82011-0
In summary, CWD prions are efficiently transmitted to WTD via aerosolization using a delivered dose substantially lower than previously reported by the oral route. Our results provide further evidence that prions delivered to the nasal passages are sufficient to transmit CWD and allow the inference that aerosolization may facilitate the transmission of prions in general.
https://journals.asm.org/doi/10.1128/jvi.02852-12
In summary, our results establish aerosols as a surprisingly efficient modality of prion transmission. This novel pathway of prion transmission is not only conceptually relevant for the field of prion research, but also highlights a hitherto unappreciated risk factor for laboratory personnel and personnel of the meat processing industry. In the light of these findings, it may be appropriate to revise current prion-related biosafety guidelines and health standards in diagnostic and scientific laboratories being potentially confronted with prion infected materials. While we did not investigate whether production of prion aerosols in nature suffices to cause horizontal prion transmission, the finding of prions in biological fluids such as saliva, urine and blood suggests that it may be worth testing this possibility in future studies.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1001257
So, this is what we leave our children and grandchildren?
2001, I remember what someone told me ‘In Confidence’, about Scrapie, I never forgot, and it seems it’s come to pass;
***> 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…so, this is what we leave our children and grandchildren?
Aug 18, 2021
Oh, Deer
Heading Off a Wildlife Epidemic
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.
https://www.recenter.tamu.edu/articles/tierra-grande/oh-d
Plants as vectors for environmental prion transmission
Published: November 09, 2023DOI: https://doi.org/10.1016/j.isci.2023.108428
Advertisement Highlights
• Abnormal prion protein can enter the roots of plants
• Plants can translocate detectable levels of prions to aerial tissues
•Animals exposed to prion-contaminated plant tissues can acquire disease
•Contaminated plants may represent a route of prion exposure
Snip…
Nonetheless, our finding of accumulation of two prion strains by a variety of plants grown hydroponically, in agar, or on soil supports the potential for plants to acquire CWD, scrapie, or other prions from the environment and transmit prion disease to susceptible hosts, making plants a plausible vector for prion diseases in wildlife, livestock, and humans. The potential for plants to serve as vectors for prion disease has implications for the disposal of infected carcasses, grazing practices, and the use and transport of potentially contaminated crop materials.
https://www.cell.com/iscience/pdf/S2589-0042(23)02505-1.pdf
https://www.cell.com/iscience/fulltext/S2589-0042(23)02505-1?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004223025051%3Fshowall%3Dtrue
Carrot plants as potential vectors for CWD transmission.
The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions and in carrot plants (leaves and roots) grown on them. Bioassays showed that both plants and roots contained CWD prions sufficiently to induce disease. As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. 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.
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
“In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.”
Regulation No. 1599 of 2018 on additional requirements for the import of hay and straw for used for animal feed.
Country Norway
Type of law Regulation
Source
FAO , FAOLEX
In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.
http://faolex.fao.org/docs/pdf/nor189761.pdf
Volume 31, Number 1—January 2025
Dispatch
Detection of Prions in Wild Pigs (Sus scrofa) from Areas with Reported Chronic Wasting Disease Cases, United States
Abstract
Using a prion amplification assay, we identified prions in tissues from wild pigs (Sus scrofa) living in areas of the United States with variable chronic wasting disease (CWD) epidemiology. Our findings indicate that scavenging swine could play a role in disseminating CWD and could therefore influence its epidemiology, geographic distribution, and interspecies spread.
Snip…
Conclusions In summary, results from this study showed that wild pigs are exposed to cervid prions, although the pigs seem to display some resistance to infection via natural exposure. Future studies should address the susceptibility of this invasive animal species to the multiple prion strains circulating in the environment. Nonetheless, identification of CWD prions in wild pig tissues indicated the potential for pigs to move prions across the landscape, which may, in turn, influence the epidemiology and geographic spread of CWD.
https://wwwnc.cdc.gov/eid/article/%2031/1/24-0401_article
Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health.
2. Determined that pigs naturally exposed to chronic wasting disease (CWD) may act as a reservoir of CWD infectivity. Chronic wasting disease is a naturally occurring, fatal, neurodegenerative disease of cervids. The potential for swine to serve as a host for the agent of CWD disease is unknown. The purpose of this study was to investigate the susceptibility of swine to the CWD agent following experimental oral or intracranial inoculation. Pigs were assigned to 1 of 3 groups: intracranially inoculated; orally inoculated; or non-inoculated. At market weight age, half of the pigs in each group were tested ('market weight' groups). The remaining pigs ('aged' groups) were allowed to incubate for up to 73 months post inoculation (MPI). Tissues collected at necropsy were examined for disease-associated prion protein (PrPSc) by multiple diagnostic methods. Brain samples from selected pigs were bioassayed in mice expressing porcine prion protein. Some pigs from each inoculated group were positive by one or more tests. Bioassay was positive in 4 out of 5 pigs assayed. Although only small amounts of PrPSc were detected using sensitive methods, this study demonstrates that pigs can serve as hosts for CWD. Detection of infectivity in orally inoculated pigs using mouse bioassay raises the possibility that naturally exposed pigs could act as a reservoir of CWD infectivity. Currently, swine rations in the U.S. could contain animal derived components including materials from deer or elk. In addition, feral swine could be exposed to infected carcasses in areas where CWD is present in wildlife populations. The current feed ban in the U.S. is based exclusively on keeping tissues from TSE infected cattle from entering animal feeds. These results indicating the susceptibility of pigs to CWD, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=353091
https://www.ars.usda.gov/research/project/?accnNo=432011&fy=2017
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337105
https://www.ars.usda.gov/research/publications/publication/?seqNo115=326166
***> Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...terry <***
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Justin Greenlee, Jifeng Bian, Zoe Lambert, Alexis Frese, and Eric Cassmann Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, USA
Aims: The purpose of this study was to determine the susceptibility of cattle to chronic wasting disease agent from elk.
Materials and Methods: Initial studies were conducted in bovinized mice using inoculum derived from elk with various genotypes at codon 132 (MM, LM, LL). Based upon attack rates, inoculum (10% w/v brain homogenate) from an LM132 elk was selected for transmission studies in cattle. At approximately 2 weeks of age, one wild type steer (EE211) and one steer with the E211K polymorphism (EK211) were fed 1 mL of brain homogenate in a quart of milk replacer while another 1 mL was instilled intranasally. The cattle were examined daily for clinical signs for the duration of the experiment. One steer is still under observation at 71 months post-inoculation (mpi).
Results: Inoculum derived from MM132 elk resulted in similar attack rates and incubation periods in mice expressing wild type or K211 bovine PRNP, 35% at 531 days post inoculation (dpi) and 27% at 448 dpi, respectively. Inoculum from LM132 elk had a slightly higher attack rates in mice: 45% (693 dpi) in wild type cattle PRNP and 33% (468) in K211 mice. Inoculum from LL132 elk resulted in the highest attack rate in wild type bovinized mice (53% at 625 dpi), but no K211 mice were affected at >700 days. At approximately 70 mpi, the EK211 genotype steer developed clinical signs suggestive of prion disease, depression, low head carriage, hypersalivation, and ataxia, and was necropsied. Enzyme immunoassay (IDEXX) was positive in brainstem (OD=4.00, but non-detect in retropharyngeal lymph nodes and palatine tonsil. Immunoreactivity was largely limited to the brainstem, midbrain, and cervical spinal cord with a pattern that was primarily glia-associated.
Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.
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.
"Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material."
=====end
Strain characterization of chronic wasting disease in bovine-PrP transgenic mice
Nuria Jerez-Garrido1, Sara Canoyra1, Natalia Fernández-Borges1, Alba Marín Moreno1, Sylvie L. Benestad2, Olivier Andreoletti3, Gordon Mitchell4, Aru Balachandran4, Juan María Torres1 and Juan Carlos Espinosa1. 1 Centro de Investigación en Sanidad Animal, CISA-INIA-CSIC, Madrid, Spain. 2 Norwegian Veterinary Institute, Ås, Norway. 3 UMR Institut National de la Recherche Agronomique (INRA)/École Nationale Vétérinaire de Toulouse (ENVT), Interactions Hôtes Agents Pathogènes, Toulouse, France. 4 Canadian Food Inspection Agency, Ottawa, Canada.
Aims: Chronic wasting disease (CWD) is an infectious prion disease that affects cervids. Various CWD prion strains have been identified in different cervid species from North America and Europe. The properties of the infectious prion strains are influenced by amino acid changes and polymorphisms in the PrP sequences of different cervid species. This study, aimed to assess the ability of a panel of CWD prion isolates from diverse cervid species from North America and Europe to infect bovine species, as well as to investigate the properties of the prion strains following the adaptation to the bovine-PrP context.
Materials and Methods: BoPrP-Tg110 mice overexpressing the bovine-PrP sequence were inoculated by intracranial route with a panel of CWD prion isolates from both North America (two white-tailed deer and two elk) and Europe (one reindeer, one moose and one red deer).
Results: Our results show distinct behaviours in the transmission of the CWD isolates to the BoPrP-Tg110 mouse model. Some of these isolates did not transmit even after the second passage. Those able to transmit displayed differences in terms of attack rate, survival times, biochemical properties of brain PrPres, and histopathology.
Conclusions: Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study.
Funded by: MCIN/AEI /10.13039/501100011033 and by European Union NextGeneration EU/PRTR
Grant number: PCI2020-120680-2 ICRAD
"Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study."
=====end
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
MONDAY, OCTOBER 16, 2023
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...
https://chronic-wasting-disease.blogspot.com/2023/10/transmission-of-chronic-wasting-disease.html
PRION 2023 CONTINUED;
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
Chronic Wasting Disease CWD vs Scrapie TSE Prion
Volume 30, Number 8—August 2024
Research
Scrapie Versus Chronic Wasting Disease in White-Tailed Deer
Zoe J. Lambert1, Jifeng Bian, Eric D. Cassmann, M. Heather West Greenlee, and Justin J. Greenlee
Author affiliations: Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA (Z.J. Lambert); US Department of Agriculture, Ames, Iowa, USA (Z.J. Lambert, J. Bian, E.D. Cassmann, J.J. Greenlee); Iowa State University, Ames (Z.J. Lambert, M.H. West Greenlee) Suggested citation for this article
Abstract
White-tailed deer are susceptible to scrapie (WTD scrapie) after oronasal inoculation with the classical scrapie agent from sheep. Deer affected by WTD scrapie are difficult to differentiate from deer infected with chronic wasting disease (CWD). To assess the transmissibility of the WTD scrapie agent and tissue phenotypes when further passaged in white-tailed deer, we oronasally inoculated wild-type white-tailed deer with WTD scrapie agent. We found that WTD scrapie and CWD agents were generally similar, although some differences were noted. The greatest differences were seen in bioassays of cervidized mice that exhibited significantly longer survival periods when inoculated with WTD scrapie agent than those inoculated with CWD agent. Our findings establish that white-tailed deer are susceptible to WTD scrapie and that the presence of WTD scrapie agent in the lymphoreticular system suggests the handling of suspected cases should be consistent with current CWD guidelines because environmental shedding may occur.
snip…
The potential for zoonoses of cervid-derived PrPSc is still not well understood (6,18,45–47); however, interspecies transmission can increase host range and zoonotic potential (48–50). Therefore, to protect herds and the food supply, suspected cases of WTD scrapie should be handled the same as cases of CWD.
https://wwwnc.cdc.gov/eid/article/30/8/24-0007_article
Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies
Location: Virus and Prion Research
Title: Differentiation of scrapie from chronic wasting disease in white-tailed deer
Author item LAMBERT, ZOE - Oak Ridge Institute For Science And Education (ORISE) item Bian, Jifeng item Cassmann, Eric item WEST GREENLEE, HEATHER - Iowa State University item Greenlee, Justin
Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/13/2024 Publication Date: N/A Citation: N/A
Interpretive Summary: Prion diseases are a neurodegenerative disease that can spread between animals. They are caused when the normal cellular prion protein misfolds and accumulates in the host’s central nervous system. This change is irreversible and invariably causes neurological disease and death of the host. The prion disease that affects sheep, scrapie, has been recognized for hundreds of years. However, chronic wasting disease, a similar disease found in white-tailed deer (WTD), has only been recognized since the 1960s. It has long been suggested that prion disease in deer (chronic wasting disease) was caused by the prion agent from sheep (scrapie). Recently, our lab confirmed that WTD will become infected by scrapie from sheep under conditions that mimic natural exposure. The disease produced in these animals was termed WTD scrapie. This manuscript addresses the next step in disease spread: whether sick WTD can pass WTD scrapie on to other deer. We found that white-tailed deer sick with scrapie can infect other deer under conditions mimicking natural exposure. The work reported in this manuscript demonstrates that CWD is difficult to differentiate from WTD scrapie. Regardless, WTD scrapie prions accumulate in the lymphoreticular system, meaning that environmental contamination is likely through feces, saliva, and other body fluids. Controlling WTD scrapie would require precautions similar to those taken with chronic wasting disease. The presence of WTD scrapie could confound mitigation efforts for chronic wasting disease. This information will be of interest to regulatory officials, the farmed cervid industry, and officials tasked with protecting animal health such as state Departments of Agriculture, Natural Resources, or Parks and Wildlife.
Technical Abstract: White-tailed deer (WTD) are susceptible to the scrapie agent from sheep after oronasal inoculation, termed WTD scrapie. However, results from western blotting these brainstems and lymph nodes are difficult to differentiate from WTD infected with chronic wasting disease (CWD). In order to assess the transmissibility of WTD scrapie and tissue phenotypes upon its further passage in WTD, three wildtype WTD (QQ95/GG96) were oronasally inoculated with WTD scrapie. These WTD presented with clinical signs and were euthanized between 21 and 26 months post-inoculation. Enzyme immunoassay (IDEXX) confirmed the presence of misfolded prion protein in the central nervous and lymphoreticular systems of all WTD in the study. Immunohistochemical staining, western blotting, and conformational stabilities were generally similar between the misfolded prion protein of WTD scrapie and CWD, though some differences were noted. Specifically, intraneuronal accumulation of misfolded prion protein was present in retinal ganglion cells of a WTD with WTD scrapie, not CWD. Additionally, epitope mapping revealed that the misfolded prion protein of CWD is slightly longer than that of WTD scrapie. Strong differences were seen in bioassays of cervidized mice, which exhibit significantly longer survival periods when inoculated with WTD scrapie as compared to those inoculated with CWD. Overall, this article establishes that WTD are highly susceptible to the WTD scrapie agent. Though subtle molecular differences exist between the misfolded prion protein of WTD scrapie and CWD, the presence of WTD scrapie in the lymphoreticular system determines that suspected cases be handled consistent with current guidelines for CWD.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=410511
Title: Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure
Author item Greenlee, Justin item MOORE, SARAH - Orise Fellow item Cassmann, Eric item LAMBERT, ZOE - Orise Fellow item Kokemuller, Robyn item Smith, Jodi item Kunkle, Robert item KONG, QINGZHONG - Case Western Reserve University (CWRU) item WEST GREENLEE, HEATHER - Iowa State University
Submitted to: Journal of Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/4/2022 Publication Date: 11/8/2022
Citation: Greenlee, J.J., Moore, S.J., Cassmann, E.D., Lambert, Z.J., Kokemuller, R., Smith, J.D., Kunkle, R.A., Kong, Q., West Greenlee, H.M. 2022. Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure. Journal of Infectious Diseases. 227(12):1386-1395. Article jiac443. https://doi.org/10.1093/infdis/jiac443.
DOI: https://doi.org/10.1093/infdis/jiac443
Interpretive Summary: Chronic Wasting Disease (CWD), a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America, is a transmissible spongiform encephalopathy (TSE). TSEs are caused by infectious proteins called prions that are resistant to decontamination and environmental degradation. The origin of chronic wasting disease is not known, but it has many similarities to the TSE of sheep called scrapie. It has long been hypothesized that CWD could have arisen through transmission of sheep scrapie to deer. The purpose of this study was to determine if scrapie derived from sheep could be transmitted to white-tailed deer. This study reports that the deer inoculated with sheep scrapie developed clinical signs of TSE and that the abnormal prion protein could be detected in a wide range of neural and lymphoid tissues. These results indicate that deer may be susceptible to sheep scrapie if exposed to the disease in natural or agricultural settings . In addition, several strong similarities between CWD in white-tailed deer and the experimental cases of scrapie in white-tailed deer in this report suggest that it would be difficult to identify scrapie in deer were a case to occur. This information should be considered when developing plans to reduce or eliminate TSEs or advising farmers that wish to keep their deer herds free from prion diseases.
Technical Abstract: Scrapie is a prion disease of sheep and goats that is associated with widespread accumulation of abnormal prion protein (PrPSc) in the central nervous and lymphoid tissues. Chronic wasting disease (CWD) is the natural prion disease of cervid species and is similar to scrapie in sheep. The purpose of this study was to determine susceptibility of white-tailed deer (WTD) to the scrapie agent. We inoculated WTD (n=5) by a concurrent oral and intranasal exposure with the scrapie agent from sheep and (n=6) with the scrapie agent from goats. All deer exposed to the agent of scrapie from sheep had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform lesions, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blots done on samples from the brainstem, cerebellum, and lymph nodes of scrapie-infected WTD have a molecular profile similar to CWD and distinct from western blots of samples from the cerebral cortex, retina, or the original sheep scrapie inoculum. WTD are susceptible to the agent of scrapie from sheep and differentiation from CWD may be difficult.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=336834
ORIGIN OF CHRONIC WASTING DISEASE TSE PRION?COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
IN CONFIDENCE, REPORT OF AN UNCONVENTIONAL SLOW VIRUS DISEASE IN ANIMALS IN THE USA 1989
http://webarchive.nationalarchives.gov.uk/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.
https://web.archive.org/web/20060307063531/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.
***> Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
***> ”Our data suggest that the phenotype of CWD in sheep is indistinguishable from some strains of scrapie in sheep. Given our results, current detection techniques would be unlikely to distinguish CWD in sheep from scrapie in sheep if cross-species transmission occurred naturally.”
http://web.archive.org/web/20150908134715/https://cpw.state.co.us/Documents/Hunting/BigGame/CWD/PDF/ResearchArticles/JWDEpiCWD.pdf
=====
“CWD spreads among wild populations at a relatively slow rate, limited by the natural home range and dispersed nature of wild animals.”
NOW HOLD YOUR HORSES, Chronic Wasting Disease CWD of Cervid can spread rather swiftly, traveling around 50 MPH, from the back of truck and trailer, and Here in Texas, we call it ‘Trucking CWD’…terry
Preventive Veterinary Medicine Volume 234, January 2025, 106385
Use of biosecurity practices to prevent chronic wasting disease in Minnesota cervid herds
Vehicles or trailers that entered the farm were used to transport other live cervids, cervid carcasses, or cervid body parts in past 3 years in 64.3 % (95 % CI 46.3–82.3) of larger elk/reindeer herds compared to 13.6 % (95 % CI 4.7–22.4) of smaller deer herds.
Snip…
Identifying the exact pathway of initial CWD transmission to cervid herds is often not possible, in part due to many potential pathways of transmission for the infection, including both direct and indirect contact with infected farmed or wild cervids (Kincheloe et al., 2021). That study identified that transmissions from infected farmed cervids may occur from direct contact with the movement of cervids from one herd to another and from indirect contact with the sharing of equipment, vehicles, clothing, reproductive equipment, and potentially through semen or embryos.
https://www.sciencedirect.com/science/article/abs/pii/S016758772400271X
SCIENCE AND TECHNOLOGY, RESEARCH
All-out approach needed to curb chronic wasting disease ‘hotspots’ on farms, study suggests Removing access to some but not all food attractants could increase the risk of transmission of the fatal disease among mule deer.
APRIL 23, 2025 BY ADRIANNA
Reducing the number of accessible food “hotspots” like stored crops, hay bales and grain bins that attract wild deer to farms or fields could inadvertently make the spread of chronic wasting disease worse, according to a recent study published in Ecology and Evolution. https://pmc.ncbi.nlm.nih.gov/articles/PMC11840243/
The finding suggests a more comprehensive strategy is needed to help farmers and wildlife managers protect deer by controlling the spread of the fatal disease, explains Kelsey Gritter, who led the research as part of her master’s thesis in ecology. If they choose to remove these artificial attractants by making them inaccessible to the deer, they likely need to eliminate all of them rather than just a portion for the approach to be effective.
Chronic wasting disease, or CWD, affects the central nervous system of cervids such as deer, elk and moose. Alberta created an ongoing surveillance program in 1998 to track prevalence, which continues to rise in many areas, with over 75% infection in mule deer males in some local areas where CWD has been present for many years.
It is spread through direct transmission between animals, as well as environmentally as the deer shed prions (misfolded proteins) through saliva, urine and feces, says Gritter. Artificial attractants become hotspots for both forms of disease transmission.
“They cause the deer to congregate and be present in unnaturally high numbers in one location and can affect CWD transmission,” says Gritter.
These artificial attractants could encourage deer to leave their home range (the area they typically move within), which would increase the likelihood of deer from different groups infecting one another.
“There’s a lot of ways that artificial attractants can cause problems when it comes to disease spread.”
For the study, Gritter and her collaborators wanted to examine the impact of the density of artificial attractants in a particular area as well as their configuration. “Density is important because if we’re trying to reduce the impact of these sites, the number of sites is one of the things we’re able to target,” says Gritter. “And configuration is important because there may be better or worse arrangements of these sites that cause more or less contact, so when creating management strategies, we can aim to achieve configurations that are better.”
The researchers gathered behavioural data from tagged mule deer, including group size, the home range they typically roam within, and the habitat and landscape characteristics they’re naturally drawn to. The researchers looked at data taken every two hours, which also provided information on how far the deer tended to travel and how much they typically deviated from their path.
“When we have the information about the landscape and their general movement patterns, we can use that to sort of simulate their movement,” says Gritter.
With the data in hand, the researchers created a computer model to simulate different scenarios: removing all attractants at a particular location, removing a few at random, or removing them based on proximity to the deer’s preferred habitat.
They found that making some but not all attractants inaccessible to deer actually increased contact rates, particularly between different groups of deer, because the same number of deer were then gathering around the fewer remaining sites. Removing attractants near their preferred habitat, such as areas with a lot of trees and shrubs, encouraged even higher rates of contact. The only effective strategy was to remove all attractants from a particular farm or field.
While the computer simulations looked at a scenario with moderate mule deer populations, Gritter notes that further research is needed to understand what effect deer population size may have on results.
https://www.ualberta.ca/en/folio/2025/04/all-out-approach-needed-to-curb-cwd-hotspots-on-farms.html
Chronic wasting disease prions on deer feeders and wildlife visitation to deer feeding areas
Miranda H. J. Huang, Steve Demarais, Marc D. Schwabenlander, Bronson K. Strickland, Kurt C. VerCauteren, William T. McKinley, Gage Rowden, Corina C. Valencia Tibbitts … See all authors
First published: 10 February 2025
https://doi.org/10.1002/jwmg.70000
Abstract
Eliminating supplemental feeding is a common regulatory action within chronic wasting disease (CWD) management zones. These regulations target the potential for increased animal-animal contact and environmental contamination with CWD prions. Prions, the causative agent of CWD, have been detected on feeder surfaces in CWD-positive, captive deer facilities but not among free-ranging populations, and information on the relative risk of transmission at anthropogenic and natural food sources is limited. In this study, we established and maintained 13 gravity feeders from September 2022 to March 2023 in a CWD zone in northern Mississippi, USA (apparent prevalence ~30%). We set up feeders up in 3 ways: no exclusion (deer feeders, n = 7), exclusion of deer using fencing with holes cut at the ground-level to permit smaller wildlife to enter (raccoon feeders, n = 3), and environmental control feeders, which were fully fenced and not filled with feed (control feeders, n = 3). We swabbed feeder spouts at setup and at 4 intervals approximately 6 weeks apart to test for prion contamination via real-time quaking-induced conversion (RT-QuIC). We detected prions 12 weeks after setup on all deer and raccoon feeders. We compared relative transmission risk using camera traps at these feeders, 6 agronomic plantings for wildlife forage (i.e., food plots), and 7 oak mast trees. Weekly visitation rate by white-tailed deer (Odocoileus virginianus; hereafter: deer) differed (P = 0.02) among deer feeders (median = 24.5 deer/week, range = 15.6–65.7), food plots (median = 12.7, range = 3.8–24.7), and mast trees (median = 2.0, range = 0.4–5.1). Contact rates between individual deer also differed between site types (P < 0.01): deer feeders (median = 2.1 deer-to-deer contacts/week, range = 0–10.1), food plots (median = 0.1, range = 0–4.0), and mast trees (median = 0, range = 0–0.3). Raccoons also visited feeders at greater rates than food plots and mast trees (P < 0.04). Finally, we swabbed 19 feeders in 2 areas where CWD was newly detected, finding prion contamination on swabs from 4 feeders. We show that deer feeders in free-ranging populations with high CWD prevalence become contaminated with CWD prions quickly, becoming a potential site of exposure of deer to CWD prions. Our results also demonstrate the ability to find evidence of prion contamination on deer feeders, even in areas where CWD is newly detected.
Snip…
We found that supplemental feeding increased the risk of exposure to CWD prions due to contamination of feeders, increased deer visitation, and increased deer-to-deer contact.
The 12-fold increase in deer visitation to feeders compared to mast trees and 2-fold increase compared to food plots demonstrates increased risk for direct disease spread.
https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.70000
Chronic wasting disease (CWD) prion detection in environmental and biological samples from a taxidermy site and nursing facility, and instruments used in surveillance activities
Paulina Soto a b , Nancy Ho a , Mitch Lockwood c , Austin Stolte c , J. Hunter Reed c , Rodrigo Morales a b
a Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
b Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, Chile
c Texas Parks and Wildlife Department (TPWD), Kerrville, TX, United States of America
Received 20 September 2024, Revised 27 February 2025, Accepted 31 March 2025, Available online 9 April 2025, Version of Record 9 April 2025.
Cite https://doi.org/10.1016/j.scitotenv.2025.179318
Highlights
• CWD prions were identified in a taxidermy and deer nursing facility.
• Contaminated samples included waters, soils, dermestid beetles, domestic flies and a dumpster.
• Surgical instruments used to collect deer samples can get contaminated with CWD prions.
• Some of the infectious particles are readily released from surgical instruments when washed.
• Our results suggest that taxidermy practices actively contribute in the spreading of CWD.
Abstract
Chronic wasting disease (CWD) is a transmissible prionopathy affecting free-ranging and captive cervids. CWD is thought to spread through both direct and indirect transmission mechanisms. Along this line, human activities have not been thoroughly explored for their potential to spread this disease. One area of concern involves taxidermy procedures and surveillance activities as handled animals or carcasses are of unknown CWD statuses. Worrisomely, taxidermy facilities can act as foci of prion infectivity if appropriate biosecurity practices are not implemented. In this study, we evaluated the presence of infectious prions in a taxidermy facility that was possibly exposed to CWD prions. To determine this, we collected biological and environmental specimens from this site and screened them using the protein misfolding cyclic amplification (PMCA) technique. Additionally, we swabbed different surfaces possibly exposed to CWD-infected animals or carcasses. We report the presence of prions in i) waters used to digest tissues from deer carcasses, ii) soils that were in contact with the previously mentioned waters, iii) dermestid beetles used to clean skulls, iv) other insects found in the beetle shed, and iv) dumpsters where animal carcasses were disposed. Additionally, we report that surgical materials used in surveillance practices may also hold CWD prions, even after being washed with aqueous solutions. All these results suggest that CWD prions may be disseminated due to human practices and that protocols should be established to decontaminate potentially contaminated materials.
Introduction
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects multiple cervid species, including mule deer, white-tailed deer, elk, reindeer, and moose, among others (Escobar et al., 2020). CWD is widely distributed in the United States and Canada in captive and free-ranging cervids. CWD is characterized by long incubation periods, followed by a relatively short clinical phase (Rivera et al., 2019; Williams, 2005). CWD is fatal in all cases when animals are clinical, and to date, there is no feasible treatment for curing either CWD or any other prion disease (Haley and Hoover, 2015). Unfortunately, CWD is rapidly expanding in both number of animals affected and geographical areas (Bartz et al., 2024; National Wildlife Health Center, 2025). Considering this, efficient containment and diagnostic testing strategies are urgently needed.
CWD can spread within animal populations with relative ease (Otero et al., 2021). The propagation of this disease is thought to be more efficient in captive animals considering the higher animal densities found in these environments (Mathiason et al., 2009; Rivera et al., 2019; Bartelt-Hunt and Bartz, 2017; Zabel and Ortega, 2017). Nevertheless, CWD transmission is still highly efficient in free-ranging cervid populations. CWD transmission is thought to occur mostly through direct animal contacts, or indirectly through the exposure of naïve animals to contaminated environments (Denkers et al., 2013; Escobar et al., 2020; Haley et al., 2011; Mathiason et al., 2009; Miller Michael et al., 2004; Soto et al., 2024). Environmental components, including inert materials and living organisms, are thought to play relevant roles in the spread of CWD (Escobar et al., 2020; Jacobson et al., 2010a; Pritzkow et al., 2018). Different studies have shown that infectious prions can enter the environment through decaying carcasses from diseased animals (Soto et al., 2023), gestational tissues released during parturition (Bravo-Risi et al., 2021), saliva (Haley et al., 2011), and excreta (Bravo-Risi et al., 2023). Once released, prions can bind to soil and other natural and manmade components (Johnson et al., 2006; Smith et al., 2011) and become available to susceptible animals. Other organisms, including plants, predators, scavengers, parasites, insects, and annelids may also participate in these processes by interacting with contaminated environmental components or animal tissues (Carlson et al., 2023; Fischer et al., 2013; Inzalaco et al., 2023; Pritzkow et al., 2015; Soto et al., 2024). Overall, multiple components and processes are involved in CWD prion transmission and dissemination. However, most of them are understudied and/or assayed in laboratory-controlled conditions. As consequence, the specific contribution of each process/element in CWD environmental contamination is contentious.
An essential factor to consider in the spreading of CWD prions includes human activities (Mori et al., 2024). Along this line, regulatory agencies already implemented or are currently considering regulations in several of these activities including containment, animal processing, movement of animals, disposal of carcasses, and breeding practices, among others (Mateus-Pinilla et al., 2013; Mysterud and Edmunds, 2019). Although most of these practices have a potential for CWD transmission, their overall importance in CWD epidemiology is understudied. One example of this involves taxidermy procedures. Deer are regarded as one of the most popular game animals, generating a high economic output and involving various activities including deer breeding, taxidermy, meat processing, and others (Arnot et al., 2009; Bishop, 2004) (https://nri.tamu.edu/media/3968/economic-values-of-white-tailed-deer-in-texas-2022-survey-part-i.pdf). Hunters active in areas with reported CWD cases are requested to follow state, wildlife and public health recommendations (Carlson et al., 2018). In general, all agencies strongly suggest CWD animal testing before processing. Many hunters process game at private facilities and, because of no statutory authority or lack of awareness, CWD-relevant guidelines or rules may not exist for meat processing and taxidermy facilities despite their capacity to transmit CWD. Specifically, the movement of carcasses or carcasses parts from areas with a high CWD incidence to areas with little or no incidence may facilitate CWD introduction and spread. In addition, it should be considered that inappropriate disposal of carcasses and animal products may also contribute to the dissemination of this disease (Angers et al., 2009; Benestad et al., 2016). Considering the above-mentioned scenarios, proper surveillance of CWD and management of activities involving potentially infected animals and animal-derived products might help to contain it. If left unchecked, there could be profound negative impacts on human health and wildlife conservation.
In this study, we evaluated the presence of CWD prions in a taxidermy facility where deer heads are processed to prepare skull mounts. Analyses were made using the protein misfolding cyclic amplification (PMCA) technique in various biological and environmental samples. In addition, we also tested the persistence of CWD prions in surgical materials used in surveillance procedures. Our results show, for the first time, CWD-prion detection in a potentially exposed taxidermy facility. In addition, we also tested the persistence of CWD prions in surgical materials used in surveillance procedures. This information has important implications on several fronts of CWD research including environmental spreading, human-related practices, and exposure of humans to infectious animal prions.
Section snippets
Samples
The samples were collected from a taxidermy and free-ranging deer rehabilitation facility located on the same property in Val Verde County, Texas. Texas Parks and Wildlife Department (TPWD) staff were initially notified of a CWD clinical suspect on this property; this animal was ultimately euthanized and confirmed positive for CWD by the National Veterinary Services Laboratory on January 5th, 2020. Samples were collected from different areas on this property where deer heads were processed to Screening of CWD prions in environmental and processing elements from a taxidermy facility
The European mount technique is a widely utilized taxidermy practice aiming to produce a skull of an animal that is free of tissue. The first critical step in making a European mount is removing the flesh from the animal's head. This is achieved by removing the majority of the external flesh, eyeballs, ears, and the brain. Then, the de-meated skull is subjected to a maceration process using bacteria. The purpose of this step is to soften and degrade any remaining tissue on the skull. This Discussion
CWD continues expanding in distribution and prevalence in North America. Hence, an essential factor in limiting the spread of this disease is to monitor and contain infectivity foci. This has proven to be difficult considering the limited diagnostic tools available to effectively identify the CWD infectious agent (prions). Identifying and mitigating the negative role that anthropogenic activities have in promoting CWD transmission is an essential step in developing a prevention strategy. The Conclusion
In summary, the information provided in this report demonstrate how anthropogenic activities, specifically taxidermy practices, animal processing, and rehabilitation of CWD susceptible species, may facilitate CWD transmission through the environmental dissemination of CWD prions. This study, along with future research efforts characterizing the overall level of infectivity, provides relevant information on managing CWD and to control its rapid geographic expansion. …
https://www.sciencedirect.com/science/article/abs/pii/S0048969725009544
THE CWD 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
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
http://www.pnas.org/content/97/7/3418.full
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2493038/
March 13, 2025
Prion Partitioning and Persistence in Environmental Waters
https://pubs.acs.org/doi/epdf/10.1021/acs.est.4c11497?ref=article_openPDF
Prions in Waterways
https://vimeo.com/898941380?fbclid=IwAR3Di7tLuU-iagCetdt4-CVPrOPQQrv037QS1Uxz0tX3z7BuvPeYlwIp7IY
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
http://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
https://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
https://link.springer.com/content/pdf/10.1007%2Fs00705-019-04154-8.pdf
In summary, CWD prions are efficiently transmitted to WTD via aerosolization using a delivered dose substantially lower than previously reported by the oral route. Our results provide further evidence that prions delivered to the nasal passages are sufficient to transmit CWD and allow the inference that aerosolization may facilitate the transmission of prions in general.
https://journals.asm.org/doi/10.1128/jvi.02852-12
In summary, our results establish aerosols as a surprisingly efficient modality of prion transmission. This novel pathway of prion transmission is not only conceptually relevant for the field of prion research, but also highlights a hitherto unappreciated risk factor for laboratory personnel and personnel of the meat processing industry. In the light of these findings, it may be appropriate to revise current prion-related biosafety guidelines and health standards in diagnostic and scientific laboratories being potentially confronted with prion infected materials. While we did not investigate whether production of prion aerosols in nature suffices to cause horizontal prion transmission, the finding of prions in biological fluids such as saliva, urine and blood suggests that it may be worth testing this possibility in future studies.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1001257
Mineral licks as environmental reservoirs of chronic wasting disease prions
Ian H. Plummer,Chad J. Johnson,Alexandra R. Chesney,Joel A. Pedersen ,Michael D. Samuel
Abstract
Chronic wasting disease (CWD) is a fatal neurodegenerative disease of deer, elk, moose, and reindeer (cervids) caused by misfolded prion proteins. The disease has been reported across North America and recently discovered in northern Europe. Transmission of CWD in wild cervid populations can occur through environmental routes, but limited ability to detect prions in environmental samples has prevented the identification of potential transmission “hot spots”. We establish widespread CWD prion contamination of mineral licks used by free-ranging cervids in an enzootic area in Wisconsin, USA. We show mineral licks can serve as reservoirs of CWD prions and thus facilitate disease transmission. Furthermore, mineral licks attract livestock and other wildlife that also obtain mineral nutrients via soil and water consumption. Exposure to CWD prions at mineral licks provides potential for cross-species transmission to wildlife, domestic animals, and humans. Managing deer use of mineral licks warrants further consideration to help control outbreaks of CWD.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0196745#sec008
December 2014, Volume 36, Issue 6, pp 1049–1061 | Cite as
Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer
Authors Authors and affiliations Michael J. LavelleEmail authorGregory E. PhillipsJustin W. FischerPatrick W. BurkeNathan W. SewardRandal S. StahlTracy A. NicholsBruce A. WunderKurt C. VerCauteren 1. 2. 3. 4.
Article First Online: 08 April 2014
Abstract
Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids. Keywords Cervus elaphus Chronic wasting disease Elk Geophagy Mineral lick Mule deer Odocoileus hemionus
https://rd.springer.com/article/10.1007/s10653-014-9600-0
Elk and Deer Use of Mineral Licks: Implications for Disease Transmission
Kurt C. VerCauteren1*, Michael J. Lavelle1, Gregory E. Phillips1, Justin W.. Fischer1, and Randal S. Stahl1 1United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO 80521-2154, USA *Cooresponding author e-mail: kurt.c.vercauteren@aphis.usda.gov
North American cervids require and actively seek out minerals to satisfy physiological requirements. Minerals required by free-ranging cervids exist within natural and artificial mineral licks that commonly serve as focal sites for cervids. Ingestion of soils contaminated with the agent that causes chronic wasting disease (CWD) may result in risk of contracting CWD.
Our objective was to evaluate the extent and nature of use of mineral licks by CWD-susceptible cervid species. We used animal-activated cameras to monitor use of 18 mineral licks between 1 June and 16 October 2006 in Rocky Mountain National Park, north-central Colorado.. We also assessed mineral concentrations at mineral licks to evaluate correlations between visitation rates and site-specific characteristics. We collected > 400,000 images of which 991 included elk, 293 included deer, and 6 included moose.
We documented elk and deer participating in a variety of potentially risky behaviors (e.g., ingesting soil, ingesting water, defecating, urinating) while at mineral licks.
Results from the mineral analyses combined with camera data revealed that visitation was highest at sodium-rich mineral licks.
Mineral licks may play a role in disease transmission by acting as sites of increased interaction as well as reservoirs for deposition, accumulation, and ingestion of disease agents.
https://int-cwd-sympo.org/wp-content/uploads/2023/06/final-agenda-with-abstracts.pdf
DEFRA
In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.
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In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.
Friday, December 14, 2012
DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012
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36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011). The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE). Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.
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The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).
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In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.
snip.....
In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible...
UFor deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.
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Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.
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https://web.archive.org/web/20170404125557/http://webarchive.nationalarchives.gov.uk/20130822084033/http://www.defra.gov.uk/animal-diseases/files/qra_chronic-wasting-disease-121029.pdf
Title: Horizontal transmission of chronic wasting disease in reindeer
Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/29/2016 Publication Date: 12/1/2016
Citation: Moore, S., Kunkle, R., Greenlee, M., Nicholson, E., Richt, J., Hamir, A., Waters, W., Greenlee, J. 2016. Horizontal transmission of chronic wasting disease in reindeer.
Emerging Infectious Diseases. 22(12):2142-2145. doi:10.3201/eid2212.160635.
Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.
Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI). We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=328261
Conclusions
Potential sources of infectivity for direct contact animals include urine, feces, and saliva from their CWDwtd-challenged pen-mates, as has been shown for CWD-affected white-tailed deer (6,8,9). Pinpointing the source of infectivity in the indirect contact group is more difficult. Infectious prions can travel at least 30 m in airborne particulate (10), but because the negative control reindeer in the pen adjacent to the indirect contact reindeer did not become positive, a more direct route of transmission is likely in this case. Penning, feeding, and watering protocols were designed to prevent exposure of negative control and indirect contact reindeer to potential infectivity on feed and water buckets, bedding, or fencing (6,11). However, reindeer might have had access to bedding from adjacent pens that had spread into the central alleyway.
During the 5-year course of this study, reindeer were moved between pens several times to maintain an optimal number of animals per pen (Technical Appendix Figure 1). Prolonged persistence of prion infectivity in the natural environment has been documented for both CWD (2 years [5]) and scrapie (up to 16 years [12]). In addition, thorough cleaning and disinfection might not be sufficient to remove all infectivity from the environment, leading to persistence of infectivity under experimental housing conditions (13).
In reindeer challenged orally with the agent of CWD, the SS138 genotype (serine/serine at PRNPcodon 138) has been associated with susceptibility to disease and the NS138 (asparagine/serine) genotype with resistance (1). In the study we report, disease developed in reindeer with the NS138 genotype after intracranial inoculation, although the extent of lymphoreticular system involvement was significantly lower than in NN138 and SS138 reindeer. The potential association of the NN138 polymorphism with shorter survival times is interesting. However, as with all potential genotype versus phenotype interactions, care should be taken not to over-interpret these results given the small group sizes and the large number of PRNPgenotype groups in this study.
Our results demonstrate that reindeer are susceptible to the agent of CWD from white-tailed deer, mule deer, and elk sources after intracranial inoculation. Furthermore, naive reindeer are susceptible to the agent of CWD after direct and indirect exposure to CWD-infected reindeer, suggesting a high potential for horizontal transmission of CWD within and between farmed and free-ranging reindeer (and caribou) populations.
https://wwwnc.cdc.gov/eid/article/22/12/16-0635_article
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5189146/
Rapid recontamination of a farm building occurs after attempted prion removal
First published: 19 January 2019 https://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 scrapie positive 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.
https://bvajournals.onlinelibrary.wiley.com/doi/abs/10.1136/vr.105054
***>This is very likely to have parallels with control efforts for CWD in cervids.
https://pubmed.ncbi.nlm.nih.gov/30602491/
Front. Vet. Sci., 14 September 2015 | https://doi.org/10.3389/fvets.2015.00032
Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission
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.
http://journal.frontiersin.org/article/10.3389/fvets.2015.00032/full
"Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation."
15 YEARS!
Detection of prions in soils contaminated by multiple routes
Results: We are able to detect prion seeding activity at multiple types of environmental hotspots, including carcass sites, contaminated captive facilities, and scrapes (i.e. urine and saliva). Differences in relative prion concentration vary depending on the nature and source of the contamination. Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation.
Conclusions: Detection of prions in the environment is of the utmost importance for controlling chronic wasting disease spread. Here, we have demonstrated a viable method for detection of prions in complex environmental matrices. However, it is quite likely that this method underestimates the total infectious prion load in a contaminated sample, due to incomplete recovery of infectious prions. Further refinements are necessary for accurate quantification of prions in such samples, and to account for the intrinsic heterogeneities found in the broader environment.
Funded by: Wisconsin Department of Natural Resources
Prion 2023 Abstracts
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
Artificial mineral sites that pre-date endemic chronic wasting disease become prion hotspots
The detection of PrPCWD in soils at attractant sites within an endemic CWD zone significantly advances our understanding of environmental PrPCWD accumulation dynamics, providing valuable information for advancing adaptive CWD management approaches.
https://int-cwd-sympo.org/wp-content/uploads/2023/06/final-agenda-with-abstracts.pdf
Detection of chronic wasting disease prions in the farm soil of the Republic of Korea
Here, we show that prion seeding activity was detected in extracts from farm soil following 4 years of incubation with CWD-infected brain homogenate.
https://journals.asm.org/doi/10.1128/msphere.00866-24
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
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.
Prion 2022 Conference abstracts: pushing the boundaries
https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
***> 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
https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82011-0
In summary, CWD prions are efficiently transmitted to WTD via aerosolization using a delivered dose substantially lower than previously reported by the oral route. Our results provide further evidence that prions delivered to the nasal passages are sufficient to transmit CWD and allow the inference that aerosolization may facilitate the transmission of prions in general.
https://journals.asm.org/doi/10.1128/jvi.02852-12
In summary, our results establish aerosols as a surprisingly efficient modality of prion transmission. This novel pathway of prion transmission is not only conceptually relevant for the field of prion research, but also highlights a hitherto unappreciated risk factor for laboratory personnel and personnel of the meat processing industry. In the light of these findings, it may be appropriate to revise current prion-related biosafety guidelines and health standards in diagnostic and scientific laboratories being potentially confronted with prion infected materials. While we did not investigate whether production of prion aerosols in nature suffices to cause horizontal prion transmission, the finding of prions in biological fluids such as saliva, urine and blood suggests that it may be worth testing this possibility in future studies.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1001257
So, this is what we leave our children and grandchildren?
2001, I remember what someone told me ‘In Confidence’, about Scrapie, I never forgot, and it seems it’s come to pass;
***> 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…so, this is what we leave our children and grandchildren?
Aug 18, 2021
Oh, Deer
Heading Off a Wildlife Epidemic
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.
https://www.recenter.tamu.edu/articles/tierra-grande/oh-d
Plants as vectors for environmental prion transmission
Published: November 09, 2023DOI: https://doi.org/10.1016/j.isci.2023.108428
Advertisement Highlights
• Abnormal prion protein can enter the roots of plants
• Plants can translocate detectable levels of prions to aerial tissues
•Animals exposed to prion-contaminated plant tissues can acquire disease
•Contaminated plants may represent a route of prion exposure
Snip…
Nonetheless, our finding of accumulation of two prion strains by a variety of plants grown hydroponically, in agar, or on soil supports the potential for plants to acquire CWD, scrapie, or other prions from the environment and transmit prion disease to susceptible hosts, making plants a plausible vector for prion diseases in wildlife, livestock, and humans. The potential for plants to serve as vectors for prion disease has implications for the disposal of infected carcasses, grazing practices, and the use and transport of potentially contaminated crop materials.
https://www.cell.com/iscience/pdf/S2589-0042(23)02505-1.pdf
https://www.cell.com/iscience/fulltext/S2589-0042(23)02505-1?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004223025051%3Fshowall%3Dtrue
Carrot plants as potential vectors for CWD transmission.
The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions and in carrot plants (leaves and roots) grown on them. Bioassays showed that both plants and roots contained CWD prions sufficiently to induce disease. As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. 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.
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
“In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.”
Regulation No. 1599 of 2018 on additional requirements for the import of hay and straw for used for animal feed.
Country Norway
Type of law Regulation
Source
FAO , FAOLEX
In addition, hay and straw from the United States and Canada must be accompanied by a certificate from a public veterinarian that the product has been harvested in states or provinces where Chronic Wasting Disease has not been detected on deer.
http://faolex.fao.org/docs/pdf/nor189761.pdf
Volume 31, Number 1—January 2025
Dispatch
Detection of Prions in Wild Pigs (Sus scrofa) from Areas with Reported Chronic Wasting Disease Cases, United States
Abstract
Using a prion amplification assay, we identified prions in tissues from wild pigs (Sus scrofa) living in areas of the United States with variable chronic wasting disease (CWD) epidemiology. Our findings indicate that scavenging swine could play a role in disseminating CWD and could therefore influence its epidemiology, geographic distribution, and interspecies spread.
Snip…
Conclusions In summary, results from this study showed that wild pigs are exposed to cervid prions, although the pigs seem to display some resistance to infection via natural exposure. Future studies should address the susceptibility of this invasive animal species to the multiple prion strains circulating in the environment. Nonetheless, identification of CWD prions in wild pig tissues indicated the potential for pigs to move prions across the landscape, which may, in turn, influence the epidemiology and geographic spread of CWD.
https://wwwnc.cdc.gov/eid/article/%2031/1/24-0401_article
Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health.
2. Determined that pigs naturally exposed to chronic wasting disease (CWD) may act as a reservoir of CWD infectivity. Chronic wasting disease is a naturally occurring, fatal, neurodegenerative disease of cervids. The potential for swine to serve as a host for the agent of CWD disease is unknown. The purpose of this study was to investigate the susceptibility of swine to the CWD agent following experimental oral or intracranial inoculation. Pigs were assigned to 1 of 3 groups: intracranially inoculated; orally inoculated; or non-inoculated. At market weight age, half of the pigs in each group were tested ('market weight' groups). The remaining pigs ('aged' groups) were allowed to incubate for up to 73 months post inoculation (MPI). Tissues collected at necropsy were examined for disease-associated prion protein (PrPSc) by multiple diagnostic methods. Brain samples from selected pigs were bioassayed in mice expressing porcine prion protein. Some pigs from each inoculated group were positive by one or more tests. Bioassay was positive in 4 out of 5 pigs assayed. Although only small amounts of PrPSc were detected using sensitive methods, this study demonstrates that pigs can serve as hosts for CWD. Detection of infectivity in orally inoculated pigs using mouse bioassay raises the possibility that naturally exposed pigs could act as a reservoir of CWD infectivity. Currently, swine rations in the U.S. could contain animal derived components including materials from deer or elk. In addition, feral swine could be exposed to infected carcasses in areas where CWD is present in wildlife populations. The current feed ban in the U.S. is based exclusively on keeping tissues from TSE infected cattle from entering animal feeds. These results indicating the susceptibility of pigs to CWD, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=353091
https://www.ars.usda.gov/research/project/?accnNo=432011&fy=2017
https://www.ars.usda.gov/research/publications/publication/?seqNo115=337105
https://www.ars.usda.gov/research/publications/publication/?seqNo115=326166
***> Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...terry <***
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Justin Greenlee, Jifeng Bian, Zoe Lambert, Alexis Frese, and Eric Cassmann Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, USA
Aims: The purpose of this study was to determine the susceptibility of cattle to chronic wasting disease agent from elk.
Materials and Methods: Initial studies were conducted in bovinized mice using inoculum derived from elk with various genotypes at codon 132 (MM, LM, LL). Based upon attack rates, inoculum (10% w/v brain homogenate) from an LM132 elk was selected for transmission studies in cattle. At approximately 2 weeks of age, one wild type steer (EE211) and one steer with the E211K polymorphism (EK211) were fed 1 mL of brain homogenate in a quart of milk replacer while another 1 mL was instilled intranasally. The cattle were examined daily for clinical signs for the duration of the experiment. One steer is still under observation at 71 months post-inoculation (mpi).
Results: Inoculum derived from MM132 elk resulted in similar attack rates and incubation periods in mice expressing wild type or K211 bovine PRNP, 35% at 531 days post inoculation (dpi) and 27% at 448 dpi, respectively. Inoculum from LM132 elk had a slightly higher attack rates in mice: 45% (693 dpi) in wild type cattle PRNP and 33% (468) in K211 mice. Inoculum from LL132 elk resulted in the highest attack rate in wild type bovinized mice (53% at 625 dpi), but no K211 mice were affected at >700 days. At approximately 70 mpi, the EK211 genotype steer developed clinical signs suggestive of prion disease, depression, low head carriage, hypersalivation, and ataxia, and was necropsied. Enzyme immunoassay (IDEXX) was positive in brainstem (OD=4.00, but non-detect in retropharyngeal lymph nodes and palatine tonsil. Immunoreactivity was largely limited to the brainstem, midbrain, and cervical spinal cord with a pattern that was primarily glia-associated.
Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.
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.
"Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material."
=====end
Strain characterization of chronic wasting disease in bovine-PrP transgenic mice
Nuria Jerez-Garrido1, Sara Canoyra1, Natalia Fernández-Borges1, Alba Marín Moreno1, Sylvie L. Benestad2, Olivier Andreoletti3, Gordon Mitchell4, Aru Balachandran4, Juan María Torres1 and Juan Carlos Espinosa1. 1 Centro de Investigación en Sanidad Animal, CISA-INIA-CSIC, Madrid, Spain. 2 Norwegian Veterinary Institute, Ås, Norway. 3 UMR Institut National de la Recherche Agronomique (INRA)/École Nationale Vétérinaire de Toulouse (ENVT), Interactions Hôtes Agents Pathogènes, Toulouse, France. 4 Canadian Food Inspection Agency, Ottawa, Canada.
Aims: Chronic wasting disease (CWD) is an infectious prion disease that affects cervids. Various CWD prion strains have been identified in different cervid species from North America and Europe. The properties of the infectious prion strains are influenced by amino acid changes and polymorphisms in the PrP sequences of different cervid species. This study, aimed to assess the ability of a panel of CWD prion isolates from diverse cervid species from North America and Europe to infect bovine species, as well as to investigate the properties of the prion strains following the adaptation to the bovine-PrP context.
Materials and Methods: BoPrP-Tg110 mice overexpressing the bovine-PrP sequence were inoculated by intracranial route with a panel of CWD prion isolates from both North America (two white-tailed deer and two elk) and Europe (one reindeer, one moose and one red deer).
Results: Our results show distinct behaviours in the transmission of the CWD isolates to the BoPrP-Tg110 mouse model. Some of these isolates did not transmit even after the second passage. Those able to transmit displayed differences in terms of attack rate, survival times, biochemical properties of brain PrPres, and histopathology.
Conclusions: Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study.
Funded by: MCIN/AEI /10.13039/501100011033 and by European Union NextGeneration EU/PRTR
Grant number: PCI2020-120680-2 ICRAD
"Altogether, these results exhibit the diversity of CWD strains present in the panel of CWD isolates and the ability of at least some CWD isolates to infect bovine species. Cattle being one of the most important farming species, this ability represents a potential threat to both animal and human health, and consequently deserves further study."
=====end
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
MONDAY, OCTOBER 16, 2023
Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure
Price of TSE Prion Poker goes up substantially, all you cattle ranchers and such, better pay close attention here...
https://chronic-wasting-disease.blogspot.com/2023/10/transmission-of-chronic-wasting-disease.html
PRION 2023 CONTINUED;
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
Chronic Wasting Disease CWD vs Scrapie TSE Prion
Volume 30, Number 8—August 2024
Research
Scrapie Versus Chronic Wasting Disease in White-Tailed Deer
Zoe J. Lambert1, Jifeng Bian, Eric D. Cassmann, M. Heather West Greenlee, and Justin J. Greenlee
Author affiliations: Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA (Z.J. Lambert); US Department of Agriculture, Ames, Iowa, USA (Z.J. Lambert, J. Bian, E.D. Cassmann, J.J. Greenlee); Iowa State University, Ames (Z.J. Lambert, M.H. West Greenlee) Suggested citation for this article
Abstract
White-tailed deer are susceptible to scrapie (WTD scrapie) after oronasal inoculation with the classical scrapie agent from sheep. Deer affected by WTD scrapie are difficult to differentiate from deer infected with chronic wasting disease (CWD). To assess the transmissibility of the WTD scrapie agent and tissue phenotypes when further passaged in white-tailed deer, we oronasally inoculated wild-type white-tailed deer with WTD scrapie agent. We found that WTD scrapie and CWD agents were generally similar, although some differences were noted. The greatest differences were seen in bioassays of cervidized mice that exhibited significantly longer survival periods when inoculated with WTD scrapie agent than those inoculated with CWD agent. Our findings establish that white-tailed deer are susceptible to WTD scrapie and that the presence of WTD scrapie agent in the lymphoreticular system suggests the handling of suspected cases should be consistent with current CWD guidelines because environmental shedding may occur.
snip…
The potential for zoonoses of cervid-derived PrPSc is still not well understood (6,18,45–47); however, interspecies transmission can increase host range and zoonotic potential (48–50). Therefore, to protect herds and the food supply, suspected cases of WTD scrapie should be handled the same as cases of CWD.
https://wwwnc.cdc.gov/eid/article/30/8/24-0007_article
Research Project: Elucidating the Pathobiology and Transmission of Transmissible Spongiform Encephalopathies
Location: Virus and Prion Research
Title: Differentiation of scrapie from chronic wasting disease in white-tailed deer
Author item LAMBERT, ZOE - Oak Ridge Institute For Science And Education (ORISE) item Bian, Jifeng item Cassmann, Eric item WEST GREENLEE, HEATHER - Iowa State University item Greenlee, Justin
Submitted to: Emerging Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/13/2024 Publication Date: N/A Citation: N/A
Interpretive Summary: Prion diseases are a neurodegenerative disease that can spread between animals. They are caused when the normal cellular prion protein misfolds and accumulates in the host’s central nervous system. This change is irreversible and invariably causes neurological disease and death of the host. The prion disease that affects sheep, scrapie, has been recognized for hundreds of years. However, chronic wasting disease, a similar disease found in white-tailed deer (WTD), has only been recognized since the 1960s. It has long been suggested that prion disease in deer (chronic wasting disease) was caused by the prion agent from sheep (scrapie). Recently, our lab confirmed that WTD will become infected by scrapie from sheep under conditions that mimic natural exposure. The disease produced in these animals was termed WTD scrapie. This manuscript addresses the next step in disease spread: whether sick WTD can pass WTD scrapie on to other deer. We found that white-tailed deer sick with scrapie can infect other deer under conditions mimicking natural exposure. The work reported in this manuscript demonstrates that CWD is difficult to differentiate from WTD scrapie. Regardless, WTD scrapie prions accumulate in the lymphoreticular system, meaning that environmental contamination is likely through feces, saliva, and other body fluids. Controlling WTD scrapie would require precautions similar to those taken with chronic wasting disease. The presence of WTD scrapie could confound mitigation efforts for chronic wasting disease. This information will be of interest to regulatory officials, the farmed cervid industry, and officials tasked with protecting animal health such as state Departments of Agriculture, Natural Resources, or Parks and Wildlife.
Technical Abstract: White-tailed deer (WTD) are susceptible to the scrapie agent from sheep after oronasal inoculation, termed WTD scrapie. However, results from western blotting these brainstems and lymph nodes are difficult to differentiate from WTD infected with chronic wasting disease (CWD). In order to assess the transmissibility of WTD scrapie and tissue phenotypes upon its further passage in WTD, three wildtype WTD (QQ95/GG96) were oronasally inoculated with WTD scrapie. These WTD presented with clinical signs and were euthanized between 21 and 26 months post-inoculation. Enzyme immunoassay (IDEXX) confirmed the presence of misfolded prion protein in the central nervous and lymphoreticular systems of all WTD in the study. Immunohistochemical staining, western blotting, and conformational stabilities were generally similar between the misfolded prion protein of WTD scrapie and CWD, though some differences were noted. Specifically, intraneuronal accumulation of misfolded prion protein was present in retinal ganglion cells of a WTD with WTD scrapie, not CWD. Additionally, epitope mapping revealed that the misfolded prion protein of CWD is slightly longer than that of WTD scrapie. Strong differences were seen in bioassays of cervidized mice, which exhibit significantly longer survival periods when inoculated with WTD scrapie as compared to those inoculated with CWD. Overall, this article establishes that WTD are highly susceptible to the WTD scrapie agent. Though subtle molecular differences exist between the misfolded prion protein of WTD scrapie and CWD, the presence of WTD scrapie in the lymphoreticular system determines that suspected cases be handled consistent with current guidelines for CWD.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=410511
Title: Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure
Author item Greenlee, Justin item MOORE, SARAH - Orise Fellow item Cassmann, Eric item LAMBERT, ZOE - Orise Fellow item Kokemuller, Robyn item Smith, Jodi item Kunkle, Robert item KONG, QINGZHONG - Case Western Reserve University (CWRU) item WEST GREENLEE, HEATHER - Iowa State University
Submitted to: Journal of Infectious Diseases Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/4/2022 Publication Date: 11/8/2022
Citation: Greenlee, J.J., Moore, S.J., Cassmann, E.D., Lambert, Z.J., Kokemuller, R., Smith, J.D., Kunkle, R.A., Kong, Q., West Greenlee, H.M. 2022. Characterization of classical sheep scrapie in white-tailed deer after experimental oronasal exposure. Journal of Infectious Diseases. 227(12):1386-1395. Article jiac443. https://doi.org/10.1093/infdis/jiac443.
DOI: https://doi.org/10.1093/infdis/jiac443
Interpretive Summary: Chronic Wasting Disease (CWD), a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America, is a transmissible spongiform encephalopathy (TSE). TSEs are caused by infectious proteins called prions that are resistant to decontamination and environmental degradation. The origin of chronic wasting disease is not known, but it has many similarities to the TSE of sheep called scrapie. It has long been hypothesized that CWD could have arisen through transmission of sheep scrapie to deer. The purpose of this study was to determine if scrapie derived from sheep could be transmitted to white-tailed deer. This study reports that the deer inoculated with sheep scrapie developed clinical signs of TSE and that the abnormal prion protein could be detected in a wide range of neural and lymphoid tissues. These results indicate that deer may be susceptible to sheep scrapie if exposed to the disease in natural or agricultural settings . In addition, several strong similarities between CWD in white-tailed deer and the experimental cases of scrapie in white-tailed deer in this report suggest that it would be difficult to identify scrapie in deer were a case to occur. This information should be considered when developing plans to reduce or eliminate TSEs or advising farmers that wish to keep their deer herds free from prion diseases.
Technical Abstract: Scrapie is a prion disease of sheep and goats that is associated with widespread accumulation of abnormal prion protein (PrPSc) in the central nervous and lymphoid tissues. Chronic wasting disease (CWD) is the natural prion disease of cervid species and is similar to scrapie in sheep. The purpose of this study was to determine susceptibility of white-tailed deer (WTD) to the scrapie agent. We inoculated WTD (n=5) by a concurrent oral and intranasal exposure with the scrapie agent from sheep and (n=6) with the scrapie agent from goats. All deer exposed to the agent of scrapie from sheep had evidence of PrPSc accumulation. PrPSc was detected in lymphoid tissues at preclinical time points, and deer necropsied after 28 months post-inoculation had clinical signs, spongiform lesions, and widespread distribution of PrPSc in neural and lymphoid tissues. Western blots done on samples from the brainstem, cerebellum, and lymph nodes of scrapie-infected WTD have a molecular profile similar to CWD and distinct from western blots of samples from the cerebral cortex, retina, or the original sheep scrapie inoculum. WTD are susceptible to the agent of scrapie from sheep and differentiation from CWD may be difficult.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=336834
ORIGIN OF CHRONIC WASTING DISEASE TSE PRION?COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
IN CONFIDENCE, REPORT OF AN UNCONVENTIONAL SLOW VIRUS DISEASE IN ANIMALS IN THE USA 1989
http://webarchive.nationalarchives.gov.uk/20080102193705/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite its subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.
https://web.archive.org/web/20060307063531/http://www.bseinquiry.gov.uk/files/mb/m11b/tab01.pdf
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.
***> Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
***> ”Our data suggest that the phenotype of CWD in sheep is indistinguishable from some strains of scrapie in sheep. Given our results, current detection techniques would be unlikely to distinguish CWD in sheep from scrapie in sheep if cross-species transmission occurred naturally.”
https://pubmed.ncbi.nlm.nih.gov/34047228/
https://journals.sagepub.com/doi/full/10.1177/10406387211017615
Volume 28, Number 4—April 2022
Research
Increased Attack Rates and Decreased Incubation Periods in Raccoons with Chronic Wasting Disease Passaged through Meadow Voles
S. Jo Moore, Christina M. Carlson, Jay R. Schneider, Christopher J. Johnson, and Justin J. GreenleeComments to Author
Author affiliations: US Department of Agriculture, Ames, Iowa, USA (S.J. Moore, J.J. Greenlee); US Geological Survey National Wildlife Health Center, Madison, Wisconsin, USA (C.M. Carlson, J.R. Schneider, C.J. Johnson). Cite This Article
Abstract
Chronic wasting disease (CWD) is a naturally-occurring neurodegenerative disease of cervids. Raccoons (Procyon lotor) and meadow voles (Microtus pennsylvanicus) have previously been shown to be susceptible to the CWD agent. To investigate the potential for transmission of the agent of CWD from white-tailed deer to voles and subsequently to raccoons, we intracranially inoculated raccoons with brain homogenate from a CWD-affected white-tailed deer (CWDWtd) or derivatives of this isolate after it had been passaged through voles 1 or 5 times. We found that passage of the CWDWtd isolate through voles led to a change in the biologic behavior of the CWD agent, including increased attack rates and decreased incubation periods in raccoons. A better understanding of the dynamics of cross-species transmission of CWD prions can provide insights into how these infectious proteins evolve in new hosts.
Snip…
Prion diseases of free-ranging animals do not exist in isolation. Meadow voles and raccoons are widespread in North America, and their habitat ranges overlap with those of CWD-affected white-tailed deer and other cervids. Therefore, a substantial potential for exposure of these or other off-target species to CWD infectivity in the environment exists. We have demonstrated that CWDWtd from a GS96 white-tailed deer transmitted readily to raccoons. Passage of this isolate through voles followed by intracranial inoculation of raccoons with vole-derived inoculum resulted in disease with different biologic characteristics and neuropathology than the original CWDWtd isolate. These results provide strong evidence for the emergence of a novel strain of CWD after passage in meadow voles and raccoons. Therefore, interspecies transmission of CWD prions between cervids and noncervid species that share the same habitat might represent a confounding factor in CWD-management programs. In addition, passage of CWD prions threw off-target species might represent a source of novel CWD strains with unknown biologic characteristics, including zoonotic potential. Characterization of the biologic behavior of CWD isolates after cross-species transmission will help us develop more effective management strategies for CWD-affected populations.
https://wwwnc.cdc.gov/eid/article/28/4/21-0271_article
Title: The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons
Author item Cassmann, Eric item QI, XU - Case Western Reserve University (CWRU) item KONG, QINGZHONG - Case Western Reserve University (CWRU) item Greenlee, Justin
Submitted to: Meeting Abstract Publication Type: Abstract Only Publication Acceptance Date: 3/15/2023 Publication Date: 5/30/2023 Citation: Cassmann, E.D., Qi, X., Kong, Q., Greenlee, J.J. 2023.
https://journals.sagepub.com/doi/full/10.1177/10406387211017615
Volume 28, Number 4—April 2022
Research
Increased Attack Rates and Decreased Incubation Periods in Raccoons with Chronic Wasting Disease Passaged through Meadow Voles
S. Jo Moore, Christina M. Carlson, Jay R. Schneider, Christopher J. Johnson, and Justin J. GreenleeComments to Author
Author affiliations: US Department of Agriculture, Ames, Iowa, USA (S.J. Moore, J.J. Greenlee); US Geological Survey National Wildlife Health Center, Madison, Wisconsin, USA (C.M. Carlson, J.R. Schneider, C.J. Johnson). Cite This Article
Abstract
Chronic wasting disease (CWD) is a naturally-occurring neurodegenerative disease of cervids. Raccoons (Procyon lotor) and meadow voles (Microtus pennsylvanicus) have previously been shown to be susceptible to the CWD agent. To investigate the potential for transmission of the agent of CWD from white-tailed deer to voles and subsequently to raccoons, we intracranially inoculated raccoons with brain homogenate from a CWD-affected white-tailed deer (CWDWtd) or derivatives of this isolate after it had been passaged through voles 1 or 5 times. We found that passage of the CWDWtd isolate through voles led to a change in the biologic behavior of the CWD agent, including increased attack rates and decreased incubation periods in raccoons. A better understanding of the dynamics of cross-species transmission of CWD prions can provide insights into how these infectious proteins evolve in new hosts.
Snip…
Prion diseases of free-ranging animals do not exist in isolation. Meadow voles and raccoons are widespread in North America, and their habitat ranges overlap with those of CWD-affected white-tailed deer and other cervids. Therefore, a substantial potential for exposure of these or other off-target species to CWD infectivity in the environment exists. We have demonstrated that CWDWtd from a GS96 white-tailed deer transmitted readily to raccoons. Passage of this isolate through voles followed by intracranial inoculation of raccoons with vole-derived inoculum resulted in disease with different biologic characteristics and neuropathology than the original CWDWtd isolate. These results provide strong evidence for the emergence of a novel strain of CWD after passage in meadow voles and raccoons. Therefore, interspecies transmission of CWD prions between cervids and noncervid species that share the same habitat might represent a confounding factor in CWD-management programs. In addition, passage of CWD prions threw off-target species might represent a source of novel CWD strains with unknown biologic characteristics, including zoonotic potential. Characterization of the biologic behavior of CWD isolates after cross-species transmission will help us develop more effective management strategies for CWD-affected populations.
https://wwwnc.cdc.gov/eid/article/28/4/21-0271_article
Title: The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons
Author item Cassmann, Eric item QI, XU - Case Western Reserve University (CWRU) item KONG, QINGZHONG - Case Western Reserve University (CWRU) item Greenlee, Justin
Submitted to: Meeting Abstract Publication Type: Abstract Only Publication Acceptance Date: 3/15/2023 Publication Date: 5/30/2023 Citation: Cassmann, E.D., Qi, X., Kong, Q., Greenlee, J.J. 2023.
The chronic wasting disease agent from white-tailed deer is highly infectious to humanized mice after passage through raccoons (abstract).
Meeting Abstract. 4th International Chronic Wasting Disease Symposium, May 30-June 3, 2023, Denver, Colorado.
Interpretive Summary:
Technical Abstract: The aim of this study was to 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 (WTD) host. Pooled brain (GG96) from CWD positive deer was used to intracranially inoculate two WTD and one raccoon. Brain homogenates (10% w/v) from the raccoon and the WTD were used to intracranially inoculate transgenic mice (Tg40h) expressing the methionine 109 human prion protein. 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. Tg40h mice inoculated with the raccoon passaged CWD agent from WTD exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPSc was detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPSc also was detected in brain tissue by western blot and immunohistochemistry. No PrPSc was detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from WTD did not have detectable PrPSc using conventional immunoassay techniques. These results demonstrated that the host range of the CWD agent from WTD was expanded in our experimental model after one passage through raccoons.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=400777
CDC CWD TSE Prion Zoonotic Humans Update 2025
KEY POINTS
Chronic wasting disease affects deer, elk and similar animals in the United States and a few other countries.
The disease hasn't been shown to infect people.
***> However, it might be a risk to people if they have contact with or eat meat from animals infected with CWD.
https://www.cdc.gov/chronic-wasting/about/index.html
Prions in Muscles of Cervids with Chronic Wasting Disease, Norway
Volume 31, Number 2—February 2025
Research
Prions in Muscles of Cervids with Chronic Wasting Disease, Norway
Snip…
In summary, the results of our study indicate that prions are widely distributed in peripheral and edible tissues of cervids in Norway, including muscles. This finding highlights the risk of human exposure to small amounts of prions through handling and consuming infected cervids. Nevertheless, we note that this study did not investigate the zoonotic potential of the Norway CWD prions. In North America, humans have historically consumed meat from CWD-infected animals, which has been documented to harbor prions (35,44–47). Despite the potential exposure to prions, no epidemiologic evidence indicates a correlation between the occurrence of CWD cases in animals and the prevalence of human prion diseases (48). A recent bioassay study reported no transmissions from 3 Nordic isolates into transgenic mice expressing human PrP (49). Therefore, our findings should be interpreted with caution in terms of human health implications, and further research is required to determine the zoonotic potential of these CWD strains.
The presence of prions in peripheral tissues indicates that CWD may have a systemic nature in all Norwegian cervid species, challenging the view that prions are exclusively localized in the CNS in sporadic CWD of moose and red deer. Our findings expand the notion of just how widely distributed prions can be in cervids affected with CWD and call into question the capability of emerging CWD strains in terms of infectivity to other species, including humans.
Appendix
https://wwwnc.cdc.gov/eid/article/31/2/24-0903-app1.pdf
https://wwwnc.cdc.gov/eid/article/31/2/24-0903_article
Volume 31, Number 2—February 2025
Dispatch
Detection of Chronic Wasting Disease Prions in Raw, Processed, and Cooked Elk Meat, Texas, USA
Rebeca Benavente, Fraser Brydon, Francisca Bravo-Risi, Paulina Soto, J. Hunter Reed, Mitch Lockwood, Glenn Telling, Marcelo A. Barria, and Rodrigo MoralesComments to Author
Snip…
CWD prions have been detected in the muscle of both farmed and wild deer (10), and at concentrations relevant to sustain disease transmission (11). CWD prions have also been identified across several cervid species and in multiple tissues, including lymph nodes, spleen, tongue, intestines, adrenal gland, eyes, reproductive tissues, ears, lungs, and liver, among others (12–14). Those findings raise concerns about the safety of ingesting processed meats that contain tissues other than skeletal muscle (15) (Appendix). https://wwwnc.cdc.gov/eid/article/31/2/24-0906-app1.pdf .
In addition, those findings highlight the need for continued vigilance and research on the transmission risks of prion diseases and for development of new preventative and detection measures to ensure the safety of the human food supply.
Snip…
Overall, our study results confirm previous reports describing the presence of CWD prions in elk muscles (13). The data also demonstrated CWD prion persistence in food products even after processing through different procedures, including the addition of salts, spices, and other edible elements. Of note, our data show that exposure to high temperatures used to cook the meat increased the availability of prions for in vitro amplification. Considering the potential implications in food safety and public health, we believe that the findings described in this study warrant further research. Our results suggest that although the elk meat used in this study resisted different manipulations involved in subsequent consumption by humans, their zoonotic potential was limited. Nevertheless, even though no cases of CWD transmission to human have been reported, the potential for human infection is still unclear and continued monitoring for zoonotic potential is warranted.
https://wwwnc.cdc.gov/eid/article/31/2/24-0906_article
Detection of chronic wasting disease prions in processed meats
Rebeca Benavente1 , Francisca Bravo1,2, J. Hunter Reed3 , Mitch Lockwood3 , Glenn Telling4 , Rodrigo Morales1,2 1 Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; 2 Universidad Bernardo O’Higgins. Santiago, Chile; 3 Texas Parks and Wildlife Department, Texas, USA. 4 Prion Research Center, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
Aims: identify the presence of CWD prions in processed meats derived from elk.
Materials and Methods: In this study, we analyzed different processed meats derived from a CWD-positive (pre-clinical) free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, seasoned chili meats, and spiced meats. The presence of CWD-prions in these samples were assessed by PMCA using deer and elk substrates. The same analyses were performed in grilled and boiled meats to evaluate the resistance of the infectious agent to these procedures.
Results: Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities. This data suggests that CWD-prions are available to people even after meats are processed and cooked.
Conclusions: These results suggest CWD prions are accessible to humans through meats, even after processing and cooking. Considering the fact that these samples were collected from already processed specimens, the availability of CWD prions to humans is probably underestimated.
Funded by: NIH and USDA
Grant number: 1R01AI132695 and APP-20115 to RM
Acknowledgement: We would like to thank TPWD personnel for providing us with valuable samples
"Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities."
end...
PRION 2023 CONTINUED;
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
The detection and decontamination of chronic wasting disease prions during venison processing
Aims: There is a growing concern that chronic wasting disease (CWD) prions in venison pose a risk to human health. CWD prions accumulate in infected deer tissues that commonly enter the human food chain through meat processing and consumption. The United States (US) Food and Drug Administration and US Department of Agriculture now formally consider CWD-positive venison unfit for human and animal consumption. Yet, the degree to which prion contamination occurs during routine venison processing is unknown. Here, we use environmental surface swab methods to:
a) experimentally test meat processing equipment (i.e., stainless steel knives and polyethylene cutting boards) before and after processing CWD-positive venison and
b) test the efficacy of five different disinfectant types (i.e., Dawn dish soap, Virkon-S, Briotech, 10% bleach, and 40% bleach) to determine prion decontamination efficacy.
Materials and Methods: We used a real-time quaking-induced conversion (RT-QuIC) assay to determine CWD infection status of venison and to detect CWD prions in the swabs. We collected three swabs per surface and ran eight technical replicates on RT-QuIC.
Results: CWD prions were detected on all cutting boards (n= 3; replicates= 8/8, 8/8, 8/8 and knives (n= 3; replicates= 8/8, 8/8, 8/8) used in processing CWD-positive venison, but not on those used for CWD-negative venison. After processing CWD-positive venison, allowing the surfaces to dry, and washing the cutting board with Dawn dish soap, we detected CWD prions on the cutting board surface (n= 3; replicates= 8/8, 8/8, 8/8) but not on the knife (n= 3, replicates = 0/8, 0/8, 0/8). Similar patterns were observed with Briotech (cutting board: n= 3; replicates= 7/8, 1/8, 0/8; knife: n= 3; replicates = 0/8, 0/8, 0/8). We did not detect CWD prions on the knives or cutting boards after disinfecting with Virkon-S, 10% bleach, and 40% bleach.
Conclusions: These preliminary results suggest that Dawn dish soap and Briotech do not reliably decontaminate CWD prions from these surfaces. Our data suggest that Virkon-S and various bleach concentrations are more effective in reducing prion contamination of meat processing surfaces; however, surface type may also influence the ability of prions to adsorb to surfaces, preventing complete decontamination. Our results will directly inform best practices to prevent the introduction of CWD prions into the human food chain during venison processing.
Prion 2023 Abstracts
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.
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.
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
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
Snip…
***> 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
=====
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
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
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 tg650brain 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.
https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Fortuitous generation of a zoonotic cervid prion strain
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in many states or provinces of USA and Canada. Multiple in vitro conversion experiments and in vivo animal studies indicate that the CWD-to-human transmission barrier is not unbreakable. A major long-term 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.
Materials and Methods: We inoculated several sCJD brain samples into cervidized transgenic mice (Tg12), which were intended as negative controls for bioassays of brain tissues from sCJD cases who had potentially been exposed to CWD. Some of the Tg12 mice became infected and their brain tissues were further examined by Western blot as well as 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 the original CJDElkPrP in transgenic mice expressing human PrP. We passaged CJDElkPrP two more times in the Tg12 mice. We found that such second and third passage CJDElkPrP prions retained 100% transmission rate in the humanized mice, despite that the natural elk CWD isolates and CJDElkPrP share the same elk PrP sequence. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice.
Conclusions: Our data indicate that highly zoonotic cervid prion strains are not only possible but also can retain zoonotic potential after serial passages in cervids, suggesting a very significant and serious long-term risk of CWD zoonosis given that the broad and continuing spread of CWD prions will provide fertile grounds for the emergence of zoonotic CWD strains over time.
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, different tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is different from that of bvWisc-1, in the migration profile and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Acta Neuropathol 144, 767–784 (2022). https://doi.org/10.1007/s00401-022-02482-9
Published
22 August 2022
https://link.springer.com/article/10.1007/s00401-022-02482-9
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Samia Hannaoui1 · Irina Zemlyankina1 · Sheng Chun Chang1 · Maria Immaculata Arifn1 · Vincent Béringue2 · Debbie McKenzie3 · Hermann M. Schatzl1 · Sabine Gilch1
Received: 24 May 2022 / Revised: 5 August 2022 / Accepted: 7 August 2022
© The Author(s) 2022
Abstract
Prions cause infectious and fatal neurodegenerative diseases in mammals. 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 provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestation with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces, but without classical neuropathological or Western blot appearances of prion diseases. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. 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.
Keywords Chronic wasting disease · CWD · Zoonotic potential · Prion strains · Zoonotic prions
HIGHLIGHTS OF THIS STUDY
================================
Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. 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.
In this study, we evaluated the zoonotic potential of CWD using a transgenic mouse model overexpressing human M129-PrPC (tg650 [12]). We inoculated tg650 mice intracerebrally with two deer CWD isolates, Wisc-1 and 116AG [22, 23, 27, 29]. 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. We demonstrated in a human transgenic mouse model that the species barrier for transmission of CWD to humans is not absolute. The fact that its signature was not typical raises the questions whether CWD would manifest in humans as a subclinical infection, whether it would arise through direct or indirect transmission including an intermediate host, or a silent to uncovered human-to-human transmission, and whether current detection techniques will be suffcient to unveil its presence.
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.
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 defined 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 profile and the N-terminal cleavage site.
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.
“suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.”
=================================
“The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, different tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is different from that of bvWisc-1, in the migration profile and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.”
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Acta Neuropathol 144, 767–784 (2022). https://doi.org/10.1007/s00401-022-02482-9
Published
22 August 2022
https://link.springer.com/article/10.1007/s00401-022-02482-9
Supplementary Information The online version contains supplementary material available at
https://doi.org/10.1007/s00401-022-02482-9
snip...see full text;
https://link.springer.com/content/pdf/10.1007/s00401-022-02482-9.pdf
EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ...
First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132
also, see;
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.
https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
''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 ;
http://web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf
http://web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
http://web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf
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
====
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
END…tss
Transmission of scrapie prions to primate after an extended silent incubation period
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
https://www.ars.usda.gov/research/publications/publication/?seqNo115=361032
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
==============
PRION 2015 CONFERENCE
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5019500/
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 1933-690X
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
Tuesday, December 16, 2014
Evidence for zoonotic potential of ovine scrapie prions
Hervé Cassard,1, n1 Juan-Maria Torres,2, n1 Caroline Lacroux,1, Jean-Yves Douet,1, Sylvie L. Benestad,3, Frédéric Lantier,4, Séverine Lugan,1, Isabelle Lantier,4, Pierrette Costes,1, Naima Aron,1, Fabienne Reine,5, Laetitia Herzog,5, Juan-Carlos Espinosa,2, Vincent Beringue5, & Olivier Andréoletti1, Affiliations Contributions Corresponding author Journal name: Nature Communications
Volume: 5, Article number: 5821 DOI: doi:10.1038/ncomms6821 Received 07 August 2014 Accepted 10 November 2014 Published 16 December 2014
Abstract
Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie prions remains unknown. Mice genetically engineered to overexpress the human prion protein (tgHu) have emerged as highly relevant models for gauging the capacity of prions to transmit to humans. These models can propagate human prions without any apparent transmission barrier and have been used used to confirm the zoonotic ability of BSE. Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of cattle BSE.
***The serial transmission of different scrapie isolates in these mice led to the propagation of prions that are phenotypically identical to those causing sporadic CJD (sCJD) in humans.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
Subject terms: Biological sciences• Medical research At a glance
http://www.nature.com/ncomms/2014/141216/ncomms6821/full/ncomms6821.html
Friday, February 21, 2025
CWD, BAITING, AND MINERAL LICKS, WHAT IF?
https://chronic-wasting-disease.blogspot.com/2025/02/cwd-baiting-and-mineral-licks-what-if.html
Friday, February 21, 2025
Deer don’t die from CWD, it’s the insurance companies, or it's a Government conspiracy?
https://chronic-wasting-disease.blogspot.com/2025/02/deer-dont-die-from-cwd-its-insurance.html
Friday, February 21, 2025
LEGISLATING CWD TSE Prion, Bills to release Genetically Modified Cervid into the wild, what could go wrong?
https://chronic-wasting-disease.blogspot.com/2025/02/legislating-cwd-tse-prion-bills-to.html
SUNDAY, APRIL 06, 2025
Failure to prevent classical scrapie after repeated decontamination of a barn
https://prpsc.proboards.com/thread/165/failure-prevent-scrapie-repeated-decontamination
https://chronic-wasting-disease.blogspot.com/2025/04/failure-to-prevent-classical-scrapie.html
THURSDAY, APRIL 10, 2025
CWD TSE Prion, Politics, Friendly Fire, Unforeseen Consequences, What If?
https://chronic-wasting-disease.blogspot.com/2025/04/cwd-tse-prion-politics-friendly-fire.html
Friday, February 21, 2025
Distribution of Chronic Wasting Disease in North America February 2025
https://chronic-wasting-disease.blogspot.com/2025/02/distribution-of-chronic-wasting-disease.html
Recently, two young individuals, aged 15 and 21, were diagnosed with sporadic Creutzfeldt-Jakob disease (sCJD) in Canada and the United States, respectively (D'Arcy et al., 2019; Ahn et al., 2024).
https://creutzfeldt-jakob-disease.blogspot.com/2025/04/cases-of-creutzfeldt-jakob-disease-in.html
***> Creutzfeldt Jakob Disease CJD, BSE, CWD, TSE, Prion, December 14, 2024 Annual Update
https://creutzfeldt-jakob-disease.blogspot.com/2024/12/creutzfeldt-jacob-disease-cjd-bse-cwd.html
***> This old study always brings to light the long term effects of a TSE in the environment…
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.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
Saturday, December 18, 2021
Direct neural transmission of vCJD/BSE in macaque after finger incision
Second death in France in a laboratory working on prions
Creutzfeldt-Jakob disease has killed a person who handled this infectious agent at Inrae in Toulouse.
After a first death in 2019, a moratorium on work on this pathogen has been extended.
France issues moratorium on prion research after fatal brain disease strikes two lab workers
https://itseprion.blogspot.com/2021/12/direct-neural-transmission-of-vcjdbse.html
Iatrogenic TSE Prion, Friendly Fire, Unforeseen Circumstances
https://itseprion.blogspot.com/
So, this is what we leave our children and grandchildren?
Good Luck!
Terry S. Singeltary Sr.
Technical Abstract: The aim of this study was to 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 (WTD) host. Pooled brain (GG96) from CWD positive deer was used to intracranially inoculate two WTD and one raccoon. Brain homogenates (10% w/v) from the raccoon and the WTD were used to intracranially inoculate transgenic mice (Tg40h) expressing the methionine 109 human prion protein. 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. Tg40h mice inoculated with the raccoon passaged CWD agent from WTD exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPSc was detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPSc also was detected in brain tissue by western blot and immunohistochemistry. No PrPSc was detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from WTD did not have detectable PrPSc using conventional immunoassay techniques. These results demonstrated that the host range of the CWD agent from WTD was expanded in our experimental model after one passage through raccoons.
https://www.ars.usda.gov/research/publications/publication/?seqNo115=400777
CDC CWD TSE Prion Zoonotic Humans Update 2025
KEY POINTS
Chronic wasting disease affects deer, elk and similar animals in the United States and a few other countries.
The disease hasn't been shown to infect people.
***> However, it might be a risk to people if they have contact with or eat meat from animals infected with CWD.
https://www.cdc.gov/chronic-wasting/about/index.html
Prions in Muscles of Cervids with Chronic Wasting Disease, Norway
Volume 31, Number 2—February 2025
Research
Prions in Muscles of Cervids with Chronic Wasting Disease, Norway
Snip…
In summary, the results of our study indicate that prions are widely distributed in peripheral and edible tissues of cervids in Norway, including muscles. This finding highlights the risk of human exposure to small amounts of prions through handling and consuming infected cervids. Nevertheless, we note that this study did not investigate the zoonotic potential of the Norway CWD prions. In North America, humans have historically consumed meat from CWD-infected animals, which has been documented to harbor prions (35,44–47). Despite the potential exposure to prions, no epidemiologic evidence indicates a correlation between the occurrence of CWD cases in animals and the prevalence of human prion diseases (48). A recent bioassay study reported no transmissions from 3 Nordic isolates into transgenic mice expressing human PrP (49). Therefore, our findings should be interpreted with caution in terms of human health implications, and further research is required to determine the zoonotic potential of these CWD strains.
The presence of prions in peripheral tissues indicates that CWD may have a systemic nature in all Norwegian cervid species, challenging the view that prions are exclusively localized in the CNS in sporadic CWD of moose and red deer. Our findings expand the notion of just how widely distributed prions can be in cervids affected with CWD and call into question the capability of emerging CWD strains in terms of infectivity to other species, including humans.
Appendix
https://wwwnc.cdc.gov/eid/article/31/2/24-0903-app1.pdf
https://wwwnc.cdc.gov/eid/article/31/2/24-0903_article
Volume 31, Number 2—February 2025
Dispatch
Detection of Chronic Wasting Disease Prions in Raw, Processed, and Cooked Elk Meat, Texas, USA
Rebeca Benavente, Fraser Brydon, Francisca Bravo-Risi, Paulina Soto, J. Hunter Reed, Mitch Lockwood, Glenn Telling, Marcelo A. Barria, and Rodrigo MoralesComments to Author
Snip…
CWD prions have been detected in the muscle of both farmed and wild deer (10), and at concentrations relevant to sustain disease transmission (11). CWD prions have also been identified across several cervid species and in multiple tissues, including lymph nodes, spleen, tongue, intestines, adrenal gland, eyes, reproductive tissues, ears, lungs, and liver, among others (12–14). Those findings raise concerns about the safety of ingesting processed meats that contain tissues other than skeletal muscle (15) (Appendix). https://wwwnc.cdc.gov/eid/article/31/2/24-0906-app1.pdf .
In addition, those findings highlight the need for continued vigilance and research on the transmission risks of prion diseases and for development of new preventative and detection measures to ensure the safety of the human food supply.
Snip…
Overall, our study results confirm previous reports describing the presence of CWD prions in elk muscles (13). The data also demonstrated CWD prion persistence in food products even after processing through different procedures, including the addition of salts, spices, and other edible elements. Of note, our data show that exposure to high temperatures used to cook the meat increased the availability of prions for in vitro amplification. Considering the potential implications in food safety and public health, we believe that the findings described in this study warrant further research. Our results suggest that although the elk meat used in this study resisted different manipulations involved in subsequent consumption by humans, their zoonotic potential was limited. Nevertheless, even though no cases of CWD transmission to human have been reported, the potential for human infection is still unclear and continued monitoring for zoonotic potential is warranted.
https://wwwnc.cdc.gov/eid/article/31/2/24-0906_article
Detection of chronic wasting disease prions in processed meats
Rebeca Benavente1 , Francisca Bravo1,2, J. Hunter Reed3 , Mitch Lockwood3 , Glenn Telling4 , Rodrigo Morales1,2 1 Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; 2 Universidad Bernardo O’Higgins. Santiago, Chile; 3 Texas Parks and Wildlife Department, Texas, USA. 4 Prion Research Center, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
Aims: identify the presence of CWD prions in processed meats derived from elk.
Materials and Methods: In this study, we analyzed different processed meats derived from a CWD-positive (pre-clinical) free-ranging elk. Products tested included filets, sausages, boneless steaks, burgers, seasoned chili meats, and spiced meats. The presence of CWD-prions in these samples were assessed by PMCA using deer and elk substrates. The same analyses were performed in grilled and boiled meats to evaluate the resistance of the infectious agent to these procedures.
Results: Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities. This data suggests that CWD-prions are available to people even after meats are processed and cooked.
Conclusions: These results suggest CWD prions are accessible to humans through meats, even after processing and cooking. Considering the fact that these samples were collected from already processed specimens, the availability of CWD prions to humans is probably underestimated.
Funded by: NIH and USDA
Grant number: 1R01AI132695 and APP-20115 to RM
Acknowledgement: We would like to thank TPWD personnel for providing us with valuable samples
"Our results show positive prion detection in all the samples analyzed using deer and elk substrates. Surprisingly, cooked meats displayed increased seeding activities."
end...
PRION 2023 CONTINUED;
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
The detection and decontamination of chronic wasting disease prions during venison processing
Aims: There is a growing concern that chronic wasting disease (CWD) prions in venison pose a risk to human health. CWD prions accumulate in infected deer tissues that commonly enter the human food chain through meat processing and consumption. The United States (US) Food and Drug Administration and US Department of Agriculture now formally consider CWD-positive venison unfit for human and animal consumption. Yet, the degree to which prion contamination occurs during routine venison processing is unknown. Here, we use environmental surface swab methods to:
a) experimentally test meat processing equipment (i.e., stainless steel knives and polyethylene cutting boards) before and after processing CWD-positive venison and
b) test the efficacy of five different disinfectant types (i.e., Dawn dish soap, Virkon-S, Briotech, 10% bleach, and 40% bleach) to determine prion decontamination efficacy.
Materials and Methods: We used a real-time quaking-induced conversion (RT-QuIC) assay to determine CWD infection status of venison and to detect CWD prions in the swabs. We collected three swabs per surface and ran eight technical replicates on RT-QuIC.
Results: CWD prions were detected on all cutting boards (n= 3; replicates= 8/8, 8/8, 8/8 and knives (n= 3; replicates= 8/8, 8/8, 8/8) used in processing CWD-positive venison, but not on those used for CWD-negative venison. After processing CWD-positive venison, allowing the surfaces to dry, and washing the cutting board with Dawn dish soap, we detected CWD prions on the cutting board surface (n= 3; replicates= 8/8, 8/8, 8/8) but not on the knife (n= 3, replicates = 0/8, 0/8, 0/8). Similar patterns were observed with Briotech (cutting board: n= 3; replicates= 7/8, 1/8, 0/8; knife: n= 3; replicates = 0/8, 0/8, 0/8). We did not detect CWD prions on the knives or cutting boards after disinfecting with Virkon-S, 10% bleach, and 40% bleach.
Conclusions: These preliminary results suggest that Dawn dish soap and Briotech do not reliably decontaminate CWD prions from these surfaces. Our data suggest that Virkon-S and various bleach concentrations are more effective in reducing prion contamination of meat processing surfaces; however, surface type may also influence the ability of prions to adsorb to surfaces, preventing complete decontamination. Our results will directly inform best practices to prevent the introduction of CWD prions into the human food chain during venison processing.
Prion 2023 Abstracts
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
DETECTION OF CHRONIC WASTING DISEASE PRIONS IN PROCESSED MEATS.
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.
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
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
Snip…
***> 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
=====
https://intcwdsympo.files.wordpress.com/2023/06/final-agenda-with-abstracts.pdf?force_download=true
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
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 tg650brain 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.
https://www.tandfonline.com/doi/full/10.1080/19336896.2022.2091286
Fortuitous generation of a zoonotic cervid prion strain
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in many states or provinces of USA and Canada. Multiple in vitro conversion experiments and in vivo animal studies indicate that the CWD-to-human transmission barrier is not unbreakable. A major long-term 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.
Materials and Methods: We inoculated several sCJD brain samples into cervidized transgenic mice (Tg12), which were intended as negative controls for bioassays of brain tissues from sCJD cases who had potentially been exposed to CWD. Some of the Tg12 mice became infected and their brain tissues were further examined by Western blot as well as 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 the original CJDElkPrP in transgenic mice expressing human PrP. We passaged CJDElkPrP two more times in the Tg12 mice. We found that such second and third passage CJDElkPrP prions retained 100% transmission rate in the humanized mice, despite that the natural elk CWD isolates and CJDElkPrP share the same elk PrP sequence. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice.
Conclusions: Our data indicate that highly zoonotic cervid prion strains are not only possible but also can retain zoonotic potential after serial passages in cervids, suggesting a very significant and serious long-term risk of CWD zoonosis given that the broad and continuing spread of CWD prions will provide fertile grounds for the emergence of zoonotic CWD strains over time.
https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf
The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, different tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is different from that of bvWisc-1, in the migration profile and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Acta Neuropathol 144, 767–784 (2022). https://doi.org/10.1007/s00401-022-02482-9
Published
22 August 2022
https://link.springer.com/article/10.1007/s00401-022-02482-9
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Samia Hannaoui1 · Irina Zemlyankina1 · Sheng Chun Chang1 · Maria Immaculata Arifn1 · Vincent Béringue2 · Debbie McKenzie3 · Hermann M. Schatzl1 · Sabine Gilch1
Received: 24 May 2022 / Revised: 5 August 2022 / Accepted: 7 August 2022
© The Author(s) 2022
Abstract
Prions cause infectious and fatal neurodegenerative diseases in mammals. 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 provide evidence for a zoonotic potential of CWD prions, and its probable signature using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestation with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces, but without classical neuropathological or Western blot appearances of prion diseases. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. 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.
Keywords Chronic wasting disease · CWD · Zoonotic potential · Prion strains · Zoonotic prions
HIGHLIGHTS OF THIS STUDY
================================
Our results suggest that CWD might infect humans, although the transmission barrier is likely higher compared to zoonotic transmission of cattle prions. Notably, our data suggest a different clinical presentation, prion signature, and tissue tropism, which causes challenges for detection by current diagnostic assays. 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.
In this study, we evaluated the zoonotic potential of CWD using a transgenic mouse model overexpressing human M129-PrPC (tg650 [12]). We inoculated tg650 mice intracerebrally with two deer CWD isolates, Wisc-1 and 116AG [22, 23, 27, 29]. 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. We demonstrated in a human transgenic mouse model that the species barrier for transmission of CWD to humans is not absolute. The fact that its signature was not typical raises the questions whether CWD would manifest in humans as a subclinical infection, whether it would arise through direct or indirect transmission including an intermediate host, or a silent to uncovered human-to-human transmission, and whether current detection techniques will be suffcient to unveil its presence.
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.
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 defined 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 profile and the N-terminal cleavage site.
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.
“suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable.”
=================================
“The finding that infectious PrPSc was shed in fecal material of CWD-infected humanized mice and induced clinical disease, different tropism, and typical three banding pattern-PrPres in bank voles that is transmissible upon second passage is highly concerning for public health. The fact that this biochemical signature in bank voles resembles that of the Wisc-1 original deer isolate and is different from that of bvWisc-1, in the migration profile and the glyco-form-ratio, is valid evidence that these results are not a product of contamination in our study. If CWD in humans is found to be contagious and transmissible among humans, as it is in cervids [57], the spread of the disease within humans might become endemic.”
Transmission of cervid prions to humanized mice demonstrates the zoonotic potential of CWD
Acta Neuropathol 144, 767–784 (2022). https://doi.org/10.1007/s00401-022-02482-9
Published
22 August 2022
https://link.springer.com/article/10.1007/s00401-022-02482-9
Supplementary Information The online version contains supplementary material available at
https://doi.org/10.1007/s00401-022-02482-9
snip...see full text;
https://link.springer.com/content/pdf/10.1007/s00401-022-02482-9.pdf
EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ...
First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132
also, see;
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.
https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
''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 ;
http://web.archive.org/web/20090506050043/http://www.bseinquiry.gov.uk/files/yb/1994/08/00004001.pdf
http://web.archive.org/web/20090506050007/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf
http://web.archive.org/web/20090506050244/http://www.bseinquiry.gov.uk/files/yb/1994/07/00001001.pdf
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
====
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
END…tss
Transmission of scrapie prions to primate after an extended silent incubation period
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
https://www.nature.com/articles/srep11573
https://www.ars.usda.gov/research/publications/publication/?seqNo115=361032
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
==============
PRION 2015 CONFERENCE
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5019500/
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 1933-690X
WS-01: Prion diseases in animals and zoonotic potential
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20
Tuesday, December 16, 2014
Evidence for zoonotic potential of ovine scrapie prions
Hervé Cassard,1, n1 Juan-Maria Torres,2, n1 Caroline Lacroux,1, Jean-Yves Douet,1, Sylvie L. Benestad,3, Frédéric Lantier,4, Séverine Lugan,1, Isabelle Lantier,4, Pierrette Costes,1, Naima Aron,1, Fabienne Reine,5, Laetitia Herzog,5, Juan-Carlos Espinosa,2, Vincent Beringue5, & Olivier Andréoletti1, Affiliations Contributions Corresponding author Journal name: Nature Communications
Volume: 5, Article number: 5821 DOI: doi:10.1038/ncomms6821 Received 07 August 2014 Accepted 10 November 2014 Published 16 December 2014
Abstract
Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie prions remains unknown. Mice genetically engineered to overexpress the human prion protein (tgHu) have emerged as highly relevant models for gauging the capacity of prions to transmit to humans. These models can propagate human prions without any apparent transmission barrier and have been used used to confirm the zoonotic ability of BSE. Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of cattle BSE.
***The serial transmission of different scrapie isolates in these mice led to the propagation of prions that are phenotypically identical to those causing sporadic CJD (sCJD) in humans.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
Subject terms: Biological sciences• Medical research At a glance
http://www.nature.com/ncomms/2014/141216/ncomms6821/full/ncomms6821.html
Friday, February 21, 2025
CWD, BAITING, AND MINERAL LICKS, WHAT IF?
https://chronic-wasting-disease.blogspot.com/2025/02/cwd-baiting-and-mineral-licks-what-if.html
Friday, February 21, 2025
Deer don’t die from CWD, it’s the insurance companies, or it's a Government conspiracy?
https://chronic-wasting-disease.blogspot.com/2025/02/deer-dont-die-from-cwd-its-insurance.html
Friday, February 21, 2025
LEGISLATING CWD TSE Prion, Bills to release Genetically Modified Cervid into the wild, what could go wrong?
https://chronic-wasting-disease.blogspot.com/2025/02/legislating-cwd-tse-prion-bills-to.html
SUNDAY, APRIL 06, 2025
Failure to prevent classical scrapie after repeated decontamination of a barn
https://prpsc.proboards.com/thread/165/failure-prevent-scrapie-repeated-decontamination
https://chronic-wasting-disease.blogspot.com/2025/04/failure-to-prevent-classical-scrapie.html
THURSDAY, APRIL 10, 2025
CWD TSE Prion, Politics, Friendly Fire, Unforeseen Consequences, What If?
https://chronic-wasting-disease.blogspot.com/2025/04/cwd-tse-prion-politics-friendly-fire.html
Friday, February 21, 2025
Distribution of Chronic Wasting Disease in North America February 2025
https://chronic-wasting-disease.blogspot.com/2025/02/distribution-of-chronic-wasting-disease.html
Recently, two young individuals, aged 15 and 21, were diagnosed with sporadic Creutzfeldt-Jakob disease (sCJD) in Canada and the United States, respectively (D'Arcy et al., 2019; Ahn et al., 2024).
https://creutzfeldt-jakob-disease.blogspot.com/2025/04/cases-of-creutzfeldt-jakob-disease-in.html
***> Creutzfeldt Jakob Disease CJD, BSE, CWD, TSE, Prion, December 14, 2024 Annual Update
https://creutzfeldt-jakob-disease.blogspot.com/2024/12/creutzfeldt-jacob-disease-cjd-bse-cwd.html
***> This old study always brings to light the long term effects of a TSE in the environment…
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.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
Saturday, December 18, 2021
Direct neural transmission of vCJD/BSE in macaque after finger incision
Second death in France in a laboratory working on prions
Creutzfeldt-Jakob disease has killed a person who handled this infectious agent at Inrae in Toulouse.
After a first death in 2019, a moratorium on work on this pathogen has been extended.
France issues moratorium on prion research after fatal brain disease strikes two lab workers
https://itseprion.blogspot.com/2021/12/direct-neural-transmission-of-vcjdbse.html
Iatrogenic TSE Prion, Friendly Fire, Unforeseen Circumstances
https://itseprion.blogspot.com/
So, this is what we leave our children and grandchildren?
Good Luck!
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
4:08 PM
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