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Monday, June 02, 2025

Idaho Chronic Wasting Disease CWD TSE Prion Update June 2025

 Idaho Chronic Wasting Disease CWD TSE Prion Update June 2025


2024 in review: Chronic wasting disease in Unit 1 in the Panhandle Region

idfg-tjross

Monday, June 2, 2025 - 9:59 AM MDT

Managing against chronic wasting disease requires playing the long game

Throughout the course of the 2024 hunting season, three additional white-tailed deer in Unit 1 tested positive for chronic wasting disease, bringing the total number of positive detections to six since the initial detection in July 2024. The three additional positives came from deer harvested by hunters within the bounds of the Unit 1 CWD management zone.

Timeline

July 2024: CWD was first detected in Unit 1 roughly three miles outside of the town of Bonners Ferry

August 15, 2024: Idaho Fish and Game Commission approved a CWD surveillance hunt in a portion of Unit 1 to determine the initial prevalence of the disease.

August 20, 2024: CWD Community Chat open houses began each Tuesday evening in Bonners Ferry.

September 27, 2024: Sample results from the CWD surveillance hunt yielded two white-tailed deer that tested positive for CWD. Both deer were harvested within less than one mile of the original CWD detection.

October 1, 2024: A CWD management zone was established in the portion of Unit 1 within Boundary County and east of the Selkirk Mountains crest. The establishment of the CWD management zone enacted mandatory CWD testing of all hunter-harvested mule deer and white-tailed deer.

November-December 2024: Idaho Fish and Game worked with hunters to gather as many CWD samples from within the CWD management zone as possible, resulting in three additional positive detections from white-tailed deer harvested within the management zone.

Takeaways

A total of 936 white-tailed deer was sampled within the Unit 1 CWD management zone during the 2024 regular deer season, representing a drastic increase from 2023. Fish and Game would like to genuinely thank hunters for their contributions of samples and therefore a better understanding of CWD in Unit 1.

Relative to many other states, the current estimated prevalence rate (less than 1%) of the disease in the management zone is low. Low prevalence rates suggest that Fish and Game in collaboration with hunters detected the disease early. Early detection of CWD is critical, as it creates opportunities to take action to slow the rate of spread of the disease. Recent studies in Wisconsin and Wyoming, states where CWD has been present for longer periods of time, have begun reporting major declines in big game herds, underscoring the potential risks of CWD in Idaho.

The future

Recent studies have found that hunting can help keep CWD rates of spread and prevalence in check for the long haul. As such, during the 2025-26 Big Game Season Setting process, Fish and Game staff in the Panhandle Region proposed five new controlled hunts for white-tailed deer in the Unit 1 CWD management zone. All five hunts were well supported by the public; therefore, they were recommended to and adopted by the Fish and Game Commission at their March 2025 meeting.

The intent of the new hunts is to reduce CWD transmission and spread, consistent with Fish and Game’s 2021 CWD management strategy. The new hunts numbers are 1115, 1116, 1120, 1121 and 1122 in the Idaho Big Game 2025 Seasons and Rules book.

Between the addition of 100 extra antlered white-tailed deer tags, addition of 1,000 extra antlerless white-tailed deer tags and reduction of 750 antlerless white-tailed deer tags in Unit 1, there is a net increase of 350 extra deer tags available in Unit 1, with a targeted focus to increase harvest within the CWD management zone.

Unit 1 is a popular hunting destination for many white-tailed deer hunters, with almost 7,100 Idaho hunters harvesting more than 2,900 white-tailed deer in Unit 1 in 2023. Fish and Game needs hunters' help to learn more about CWD to help keep white-tailed herds healthy in north Idaho.

Fish and Game’s goal is to maintain healthy big game herds by slowing the spread of CWD and keeping the prevalence rate low. Achieving this goal is not possible without assistance from hunters.

Please contact the Panhandle Regional office at (208) 769-1414 with any questions.

Follow the Panhandle Region Facebook page for regular news and updates.



Date: January 29, 2025

Agenda Item: Chronic Wasting Disease Update Prepared by: Stacey Dauwalter

Position/Title: Wildlife Health Program Coordinator

Agenda Item No. 9

Bureau Chief Approval: SR

Background:

The Department developed the first Strategy for Chronic Wasting Disease Prevention, Detection, and Management for Idaho’s Wild Cervids (Deer, Elk, and Moose) in 2018. Since chronic wasting disease (CWD) had not been detected in Idaho at the time, the Strategy was primarily focused on pre-detection surveillance efforts. The Strategy was subsequently revised in 2021, just before Idaho’s first CWD detection in November 2021. Since 2021, there have been CWD detections in three additional GMUs (Units 1, 18, & 23), each with different timing, species, population demographics, and seasonal habitat use patterns. In mid-2024, staff were tasked with reviewing and updating the CWD Strategy, considering new CWD research and Idaho’s own lessons learned over the prior two and a half years. Staff are in the process of incorporating recently published research on population level impacts, surveillance strategies, management, and a new section focusing on human dimensions in the revision of the Strategy. This informational presentation will overview the anticipated revision to the Strategy and the planned timeline for its completion.

Staff will also present an update on the 2024-2025 CWD sampling and results to date. The following tables and map are accurate as of Dec 30, 2024.

Jul 1, 2024 - Dec 30, 2024

CWD Total Total Not Detected Suspect/Detected Pending (shipped)

Statewide 5691 5247 20 424

GMU 1 1392 1143 6 243

GMU 1 CMZ 1165 939 6 220

GMU 14 690 626 12 52

GMU 18 239 222 2 15

GMU 23 430 418 - 12

GMU 24 203 196 - 7

GMU 32A 258 257 - 1

Snip…see;


Jul 1, 2024 - Dec 30, 2024 CWD Total Total Not Detected Suspect/Detected Pending (shipped)

Suspect/Detected 46

Friday January 3, 2025

Idaho Second Case of CWD in Domestic Elk

Second Case of Chronic Wasting Disease Detected in Idaho Domestic Elk


Thursday December 19, 2024

First Case of Chronic Wasting Disease Detected in Idaho Domestic Elk


Thursday December 19, 2024

The infected animal was among a group of elk transported to the Idaho ranch in March 2023 from a facility in Alberta, Canada.


Tuesday, April 2, 2024

Idaho, second year of the CWD management action has concluded, IDFG would like to take this opportunity to share the results. Results of Slate Creek area management action includes 16 CWD positive animals 10%…


Wednesday, November 8, 2023

Mule deer taken in Hunting Unit 32A tests positive for chronic wasting disease:


SATURDAY, APRIL 08, 2023

Idaho 24 animals tested positive for CWD from 442 animals removed in the Slate Creek management area within unit 14


MONDAY, FEBRUARY 06, 2023

Idaho detects 15 deer with chronic wasting disease in 2022 out of 3,171 tests statewide


SATURDAY, OCTOBER 22, 2022

Idaho Another case of chronic wasting disease found in Unit 14


THURSDAY, FEBRUARY 10, 2022

Idaho Fish and Game Commission will consider proposed hunting season changes for Unit 14 in response to five deer and an elk testing positive for Chronic Wasting Disease


THURSDAY, JANUARY 13, 2022

Idaho Two more Chronic Wasting Disease cases detected in cow elk and white-tailed doe in Unit 14


FRIDAY, DECEMBER 31, 2021

Idaho Two white-tailed deer test positive for Chronic Wasting Disease in same area as previous CWD cases


THURSDAY, NOVEMBER 18, 2021

Idaho Chronic Wasting Disease detected in two mule deer first time ever detected there


SATURDAY, JULY 21, 2018

Idaho Fish and Game Commission Quarterly Meeting July 25 26, 2018 Chronic Wasting Disease CWD TSE Prion


THURSDAY, APRIL 24, 2025

***> US Captive CWD Positive Herds Update April 2025

https://chronic-wasting-disease.blogspot.com/2025/04/us-captive-cwd-positive-herds-update.html

“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’…

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.


Chronic Wasting Disease in Texas A Real Disease with Proven Impacts

Produced by a coalition of concerned hunters, landowners, & conservationists (last update 1/2025)


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.


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.


Texas Game Wardens Bust Illegal Deer Operations Across the State Feb. 27, 2025


TUESDAY, FEBRUARY 25, 2025

TEXAS ANIMAL HEALTH COMMISSION 423rd Commission Meeting CWD Update February 25, 2025


***> 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. <***


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



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/

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

Prions in Waterways

https://vimeo.com/898941380?fbclid=IwAR3Di7tLuU-iagCetdt4-CVPrOPQQrv037QS1Uxz0tX3z7BuvPeYlwIp7IY

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

So, this is what we leave our children and grandchildren?

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

"Additionally, we have determined that prion seeding activity is retained for at least fifteen years at a contaminated site following attempted remediation."

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

***> 15 YEARS!!!

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

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

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

***> 14 TO 21 YEARS!

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. snip...

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/

What about the Real Estate Market?

I remember what I was told about Scrapie way back around 2001, 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

So, this is what we leave our children and grandchildren?

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

CATTLE, SHEEP, PIGS, CERVID, MONKEYS, CWD, TSE, PRION, OH MY!

the U.K. mad cow BSE Bovine Spongiform Encephalopathy TSE Prion epidemic, where some 300,000 cattle had BSE, they did NOT “medicate” them with any cure. It was the feed, they stopped feeding the cattle feed with animal products that was infected with a TSE prion. Which reminds me…

Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease

Nathaniel D Denkers 1 , Clare E Hoover 2 , Kristen A Davenport 3 , Davin M Henderson 1 , Erin E McNulty 1 , Amy V Nalls 1 , Candace K Mathiason 1 , Edward A Hoover 1

These studies suggest that the CWD minimum infectious dose approximates 100 to 300 ng CWD-positive brain (or saliva equivalent), and that CWD infection appears to conform more with a threshold than a cumulative dose dynamic.

Snip…

Discussion

As CWD expands across North America and Scandinavia, how this disease is transmitted so efficiently remains unclear, given the low concentrations of prions shed in secretions and excretions [13, 14]. The present studies demonstrated that a single oral exposure to as little as 300nmg of CWD-positive brain or equivalent saliva can initiate infection in 100% of exposed white-tailed deer. However, distributing this dose as 10, 30 ng exposures failed to induce infection. Overall, these results suggest that the minimum oral infectious exposure approaches 100 to 300 ng of CWD-positive brain equivalent. These dynamics also invite speculation as to whether potential infection co-factors, such as particle binding [46, 47] or compromises in mucosal integrity may influence infection susceptibility, as suggested from two studies in rodent models [48, 49].

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0237410

PRION 2023 CONTINUED;

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

Prion 2023 Experimental Oronasal Inoculation of the Chronic Wasting Disease Agent into White Tailed Deer

Aims: The purpose of this experiment was to determine whether white-tailed deer (WTD) are susceptible to inoculation of chronic wasting disease (CWD) via oronasal exposure.

Results: All deer developed characteristic clinical signs of CWD including weight loss, regurgitation, and ataxia…

PRION 2023 CONTINUED;

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

MAFF PRESS RELEASE BSE TRANSMISSION EXPERITMENT IN PIGS

https://webarchive.nationalarchives.gov.uk/ukgwa/20080102222859mp_/http://www.bseinquiry.gov.uk/files/yb/1990/09/24007001.pdf

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

Transmission of the chronic wasting disease agent from elk to cattle after oronasal exposure

Conclusions: Cattle with the E211K polymorphism are susceptible to the CWD agent after oronasal exposure of 0.2 g of infectious material.

"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

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.

"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."

https://prion2023.org/wp-content/uploads/2023/10/Meeting-book-final-version2.pdf

Control of Chronic Wasting Disease OMB Control Number: 0579-0189APHIS-2021-0004 Singeltary Submission

https://www.regulations.gov/comment/APHIS-2021-0004-0002

https://downloads.regulations.gov/APHIS-2021-0004-0002/attachment_1.pdf

Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification

https://www.regulations.gov/document/APHIS-2018-0011-0003

https://downloads.regulations.gov/APHIS-2018-0011-0003/attachment_1.pdf

APHIS Indemnity Regulations [Docket No. APHIS-2021-0010] RIN 0579-AE65 Singeltary Comment Submission

Comment from Singeltary Sr., Terry

Posted by the Animal and Plant Health Inspection Service on Sep 8, 2022

https://www.regulations.gov/comment/APHIS-2021-0010-0003

https://downloads.regulations.gov/APHIS-2021-0010-0003/attachment_1.pdf

Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed

PUBLIC SUBMISSION

Comment from Terry Singeltary Sr.

Posted by the Food and Drug Administration on May 17, 2016 Comment

Docket No. FDA-2003-D-0432 (formerly 03D-0186) Use of Material from Deer and Elk in Animal Feed Singeltary Submission

https://www.regulations.gov/comment/FDA-2003-D-0432-0011

https://www.regulations.gov/docket/FDA-2003-D-0432

CWD TSE Prion Zoonosis ?

First, let’s go way back, then to date, about Cwd and cjd risk factors (I don’t make this stuff up).

regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD

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@ …

######## Bovine Spongiform Encephalopathy <BSE-L@UNI-KARLSRUHE.DE> #########

Dear Terry,

An excellent piece of review as this literature is desparately 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

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############

Subject: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY

From: "Terry S. Singeltary Sr." <flounder@WT.NET>

Reply To: Bovine Spongiform Encephalopathy <BSE-L@UNI-KARLSRUHE.DE>

Date: Thu, 17 Oct 2002 17:04:51 -0700

snip...

''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

Stephen Dealler is a consultant medical microbiologist deal@airtime.co.uk

BSE Inquiry Steve Dealler

Management In Confidence

BSE: Private Submission of Bovine Brain Dealler

snip...end

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############

BSE INQUIRY

CJD9/10022

October 1994

Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane

BerksWell Coventry CV7 7BZ

Dear Mr Elmhirst,

CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT

Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.

The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended.. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.

The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.

The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.

I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all.

http://web.archive.org/web/20030511010117/http://www.bseinquiry.gov.uk/files/yb/1994/10/00003001.pdf

TSE in wild UK deer? The first case of BSE (as we now realise) was in a nyala in London zoo and the further zoo cases in ungulates were simply thought of as being interesting transmissions of scrapie initially. The big problem started to appear with animals in 1993-5 when it became clear that there was an increase in the CJD cases in people that had eaten deer although the statistics involved must have been questionable. The reason for this was that the CJD Surveillance was well funded to look into the diet of people dying of CJD. This effect is not clear with vCJD...if only because the numbers involved are much smaller and hence it is difficult to gain enough statistics. They found that many other foods did not appear to have much association at all but that deer certainly did and as years went by the association actually became clearer. The appearance of vCJD in 1996 made all this much more difficult in that it was suddenly clearer that the cases of sporadic CJD that they had been checking up until then probably had nothing to do with beef...and the study decreased. During the period there was an increasing worry that deer were involved with CJD..

see references:

DEER BRAIN SURVEY

https://web.archive.org/web/20090506025229/http://www.bseinquiry.gov.uk/files/yb/1991/11/20004001.pdf

CONFIDENTIAL AND IN CONFIDENCE TRANSMISSION TO CHIMPANZEES AND PIGS

IN CONFIDENCE

TRANSMISSION TO CHIMPANZEES

Kuru and CJD have been successfully transmitted to chimpanzees but scrapie and TME have not.

We cannot say that scrapie will not transmit to chimpanzees. There are several scrapie strains and I am not aware that all have been tried (that would have to be from mouse passaged material). Nor has a wide enough range of field isolates subsequently strain typed in mice been inoculated by the appropriate routes (i/c, i/p and i/v).

I believe the proposed experiment to determine transmissibility, if conducted, would only show the susceptibility or resistance of the chimpanzee to infection/disease by the routes used and the result could not be interpreted for the predictability of the susceptibility for man. proposals for prolonged oral exposure of chimpanzees to milk from cattle were suggested a long while ago and rejected.

In view of Dr Gibbs' probable use of chimpazees Mr Wells' comments (enclosed) are pertinent. I have yet to receive a direct communication from Dr Schellekers but before any collaboration or provision of material we should identify the Gibbs' proposals and objectives.

A positive result from a chimpanzee challenged severely would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.

A negative result would take a lifetime to determine but that would be a shorter period than might be available for human exposure and it would still not answer the question regarding mans ‘susceptibility. In the meantime no doubt the negativity would be used defensively. It would however be counterproductive if the experiment finally became positive. We may learn more about public reactions following next Monday's meeting.

R Bradley

CVO (+ Mr Wells’ commenters 23 September 1990 Dr T W A Little Dr B J Shreeve

90/9.23/1.1

https://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf

*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.

see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ????

“Our conclusion stating that we found no strong evidence of CWD transmission to humans”

From: TSS Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam, In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091).

Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D. Centers for Disease Control and Prevention

-----Original Message----- From:

Sent: Sunday, September 29, 2002 10:15 AM

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS

Thursday, April 03, 2008

A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.

snip... *** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,

snip... full text ;

http://chronic-wasting-disease.blogspot.com/2008/04/prion-disease-of-cervids-chronic.html

However, to date, no CWD infections have been reported in people.

sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven. if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;

sporadic = 54,983 hits

https://www.ncbi.nlm.nih.gov/pubmed/?term=sporadic

spontaneous = 325,650 hits

https://www.ncbi.nlm.nih.gov/pubmed/?term=spontaneous

key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD.

SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry

*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***

However, to date, no CWD infections have been reported in people. key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry

*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***

*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***

http://www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys

http://www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true

https://wwwnc.cdc.gov/eid/article/20/1/13-0858_article

So, this is what we leave our children and grandchildren?

CDC CWD TSE Prion 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

Volume 31, Number 4—April 2025

Research

Detection and Decontamination of Chronic Wasting Disease Prions during Venison Processing

https://wwwnc.cdc.gov/eid/article/31/4/24-1176_article

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

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

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

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

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

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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.”

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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/article/10.1007/s00401-022-02482-9

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

***> Creutzfeldt Jakob Disease CJD TSE Prion Cases Increasing March 2025

https://creutzfeldt-jakob-disease.blogspot.com/2025/03/creutzfeldt-jakob-disease-tse-prion.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

https://creutzfeldt-jakob-disease.blogspot.com/

Iatrogenic Transmissible Spongiform Encephalopathy TSE Prion, CWD, our worst nightmare, what if?

https://itseprion.blogspot.com/

So, this is what we leave our children and grandchildren?

Terry S. Singeltary Sr.
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