SEAFWA COMMITTEE Cervid Working Group Report August 16, 2022 CWD TSE Prion Report
SEAFWA COMMITTEE Cervid Working Group Report August 16, 2022 CWD TSE Prion Report
SOUTHEASTERN ASSOCIATION OF FISH AND WILDLIFE AGENCIES WILDLIFE RESOURCES COMMITTEE Cervid Working Group Report August 16, 2022
snip...
Update on Southeast CWD Bi-Monthly Meeting Discussion - Isabelle An update was given by Jason Isabelle and Moriah Boggess on the newly formed bi-monthly Southeast Chronic Wasting Disease (SECWD) Call. This call is open to Southeast Deer Project Leaders and Wildlife Health Staff for all the Southeast states. The call gives states the opportunity to provide an update on their CWD status, as well as discuss a variety of strategies each state is using to fight CWD. The meeting also allows for individuals outside of the SE to give a talk to the group on certain topics about CWD.
snip...
State Report Highlights (see attached state reports for additional information)
Alabama
Alabama hunters reported harvesting 186,427 deer through Game Check during the 2021-22 hunting season.
Research. Participating state in the Surveillance Optimization Project for Chronic Wasting Disease (SOP4CWD) project led by the Cornell Wildlife Health Lab at the Cornell College of Veterinary Medicine and by the Boone and Crockett Quantitative Wildlife Center at Michigan State University.
Deer Enclosure Registration License. Legislature approved license which allows registrants to hunt deer inside of registered enclosures with modern firearms from October 15 through January 6. Annual registration cost is $2,500 per enclosure. All registration fees will go into Game and Fish Fund.
CWD. Alabama’s first CWD positive deer was confirmed in Lauderdale County on January 6, 2022. The 3.5-year old hunter harvested buck was sampled as part of ADWFF’s annual CWD surveillance efforts.
A second 3.5-year old hunter harvested buck also tested positive on February 18, 2022.
Arkansas
AR hunters reported harvesting 181,374 deer during the 2021-22 hunting season.
Research. Population-level impacts of chronic wasting disease on Arkansas’s white-tailed deer. This study is being conducted by the University of Georgia. The primary objectives of the study are to estimate the current abundance of white-tailed deer in the CWD management zone; examine survival and recruitment of white-tailed deer in the CWD management zone and to compare these parameters between CWD positive and presumed negative individuals; examine movement and home range size of white-tailed deer within the CWD management zone and to compare these between CWD positive and presumed negative individuals; calculate infection rates of CWD in white-tailed deer by age class and sex, calculate mortality rates and determine causes of mortality for CWD positive and presumed negative white-tailed deer; and lastly to use the above data to populate a model that will examine current and future population trends in the presence of CWD to help inform future management decisions. Researchers began field work in January 2021 and have collared a total of 199 deer (33 bucks, 71 does, and 90 fawns).
Research. Screening single nucleotide polymorphisms (SNP) variation to model deer dispersal in Arkansas. This study was completed by the Arkansas Conservation and Molecular Ecology Laboratory at the University of Arkansas. The primary objective was to determine likely origin of seven CWD positive deer collected in FY2022.
CWD. Overall, 8,389 samples were tested this sampling season (2021-22), resulting in 209 CWD positive detections (9 elk and 200 WTD).
CWD. Five Arkansas counties detected their 1st CWD positive WTD this season. Florida According to the harvest reporting system, 43,795 deer were harvested statewide in the 2021- 22 season.
Completed third year of harvest reporting and average of 59% compliance rate.
Research. North Florida Deer Study. In January 2022, a new Ph.D. student from the University of Florida began field work at the second study site of the North Florida Deer Study, a 5-year population dynamics study to investigate survival, fawn recruitment, and survey methods on two study sites in north Florida.
CWD. Since 2002, FWC has tested over 17,000 hunter-killed, road-killed, and sick/diseased deer. FWC continues to work to collect samples from high priority counties and has developed a CWD introduction risk model with the assistance of the Cornell Wildlife Health Laboratory.
Georgia
Georgia hunters reported a deer harvest of 257,441 during the 2021-22 season.
Research. The southwest Georgia breeding study completed another field season of data collection.
Research. The Georgia Department of Natural Resources is currently working with UGA to develop a human dimensions project for opinions and attitudes towards CWD management.
Georgia’s new DMAP is administered by three experienced wildlife biologists under guidance of the State Deer Biologist. Since the launch of the program in November of 2019, DMAP biologists have provided technical guidance to over 275 customers with a total affected land area of 294,000 acres. Of those, 117 customers have enrolled their private property or hunting club in DMAP with a total 163,162 acres in the program. Georgia’s DMAP was designed to provide assistance to everyone, regardless of property size.
CWD. Chronic Wasting Disease (CWD) has not been found in Georgia to date. WRD staff collected 1,404 samples in 2021-22.
Kentucky
Kentucky hunters reported harvesting 132,328 deer during the 2021-2022 hunting season.
Research. No current research.
Since 2002, more than 42,800 deer and 860 elk have been tested for the disease and CWD has yet to be detected in Kentucky
Louisiana
The 2021-22 reported deer harvest was 102,725 compared to the hunter harvest survey estimate of 233,400.
A license restructure was passed in the spring of 2021 by the Louisiana legislature. The changes consolidated the total number of licenses and increased the fees on most privileges. The license and fee restructure affected fishing, hunting and commercial license holders. It was the first fee increase in 20 years for recreational licenses and 35 years for commercial licenses.
CWD. Louisiana became the 29th state to detect CWD. The index case was a hunter harvested 8.5 year old buck that also displayed symptoms of the disease. No additional positives have been detected. LDWF collected 1,602 CWD samples statewide in 2021-22 (13,771 since 2002).
Maryland
Maryland hunters reported a deer harvest of 70,845 deer during the 2021-22 deer season.
Research. Small-scale contraception/sterilization projects continued; continued cooperation with various CWD research projects in the region; public opinion survey of sika deer hunters on the Eastern Shore continues; and pilot study to evaluate vaginal implant transmitters for sika deer initiated.
CWD. 710 CWD samples were collected in the 2021-2022 season. Of those samples, 53 tested positive for CWD. All CWD positives were detected within the existing disease management area (Allegany and Washington counties). A total of 133 CWD positive cases have been detected out of 11,592 total samples collected since 1999. Mississippi
MS hunters reported harvesting 268,242 deer during the 2021-2022 hunting season. Research. Research projects include Deer Home Ranges in CWD Management Zones, Adult Male White-tailed Deer Focal Areas, Can Scrapes Serve as Early Warning Sites for Presence of CWD?, Improving CWD Educational Outreach via Social Media Platforms, Effects of Fire Season on Tree Survival and Understory Plants, and Surveillance Optimization Project for Chronic Wasting Disease (SOP4CWD).
CWD. Mississippi currently has detected 134 CWD positive deer in nine counties. CWD Management Tags for properties within 3 miles of known positives; either-sex tags allow any weapon all season (began in 2020-2021 season). Resulted in 34% of total positives in 2021 and 31% of positives in 2022.
Missouri
The 2021-2022 deer season harvest total was 295,143.
Research. Modeling the Effects and Risks of Common Harvest Strategies and Human Practices to Promote Effective Management of CWD. A collaborative project between MDC and the University of MT to evaluate the effects of targeted culling on CWD prevalence rates, identify trigger-points to guide targeted culling efforts, and identify alternative harvest strategies to manage CWD.
Identifying and Understanding Landowner Motivations and Barriers to Participating in MDC CWD Culling Programs. Research project using focus groups and mail survey of landowners within CWD Core Areas to identify and assess barriers and motivations that drive landowner participation in targeted culling, and obtain information to help design programs to recruit and retain targeted culling landowner participants.
Evaluation of CWD Sample Prevalence and Targeted Removal Efficacy. This research project uses a Bayesian modeling framework to examine CWD sample prevalence over time in Missouri and develop techniques to evaluate the potential impacts of targeted removals on CWD prevalence rates and spatial distribution.
Development and Application of MEMS-Based Biosensor and RT-QuIC Assay for the Detection of Chronic Wasting Disease Prion in Ante- and Post-Mortem Cervid Samples. Collaborative project between MDC and the University of Missouri College of Engineering and Veterinary Medicine. Objectives include developing a Nano technology (MEMS microelectromechanical system) to detect small quantities of pathologic prion, allowing detection of CWD at earlier stages of disease than existing methods.
Prion Strain-typing Research Project. Collaborative project with Colorado State University (CSU) and several state fish and wildlife agencies. Research project will examine the diversity of potential CWD strain-types at various geographic scales and has the potential to identify unique strains of CWD, characterize potential associated differences in disease dynamics, and potentially provide insight to CWD spread on a large scale.
In 2019, MDC piloted a Deer Management Assistance Program (DMAP) in seven counties, and the program has continued to expand each year thereafter. During the 2022-2023 deer season, the program will be available statewide for the first time.
CWD. During the 2021-2022 CWD surveillance year, more than 32,000 free-ranging deer were sampled for CWD; nearly 3,100 deer were culled post-hunting season within CWD Core Areas (within 1-2 sq. mi of CWD detections); and 86 CWD+ deer were detected during the 2021-2022 CWD surveillance year. Since 2012, 292 free-ranging CWD+ deer have been detected in Missouri in 22 counties.
North Carolina
NC hunters reported harvesting 168,427 deer during the 2021-2022 hunting season. Research. Urban to Rural Deer Ecology Study. The NCWRC is collaborating with NC State University, NC Museum of Natural Sciences, USGS NC Cooperative Fish and Wildlife Research Unit, and US Forest Service Southern Research Station to study deer ecology, populations, and public perceptions of deer across an urban to rural continuum in Durham County NC. The objectives of the capture project are to determine how survival, spatial ecology, reproduction, and mortality factors vary across the continuum by collaring and monitoring ~35 does, ~30 bucks, and ~30 fawns each of three capture seasons.
Hunter Perspectives on Chronic Wasting Disease in NC
This NC State University project funded by the NCWRC is surveying hunters statewide to assess their perceptions of CWD and its management.
CWD. In late March of 2022, NCWRC was notified that CWD was detected in a sample from a buck that had been harvested in northern Yadkin County in December 2021 and submitted by a taxidermist in the Cervid Health Cooperator Program.
Oklahoma
OK hunters reported harvesting 117,630 deer during the 2021-22 hunting season.
Research. Possible elk relocation project on the horizon.
CWD. Staff collected 113 samples during our annual HHE project, with all samples returning as ‘not detected.’
South Carolina
During the 2021 deer season it is estimated that a total of 95,351 bucks and 79,218 does were harvested for a statewide total of 174,569 deer.
Research. Doe and Fawn Movement and Survival/Coyote Ecology and Deer Interactions in the Piedmont of South Carolina. A research project funded by SCDNR and being conducted by Dr. David Jachowski, Clemson University, began in January 2019 in McCormick County in the SC Piedmont. The deer project objectives are to: 1) Evaluate factors contributing to fawn mortality, 2) establish estimates of doe and fawn survivorship, and 3) track movements of doe-fawn pairs. The coyote project objectives are: 1) Compare coyote movement patterns to fawn/doe movement using GPS collar data. 2) Link deer predation with known individuals/social status based on (a) sex and size of coyote, (b) dominance based on home range overlap, and (c) relatedness based on genetic testing. 3) Evaluate movement of GPS collared coyotes in relation to deer corn feeders to assess (a) if it attracts them, (b) if they are coming together socially near feeders, and (c) if they increase deer encounter rates. 4) Use cameras at and around feeders to assess deer and coyote activity/density (marked vs. unmarked), species interactions, as well as doe:fawn ratio. Field activities and data collection on this 3-year study have concluded. During the study, 83 adult does were instrumented with GPS collars and VITs which facilitated 94 neonate fawns being collared.
Use of fecal genotyping and spatial capture-recapture modeling to investigate coyote abundance in South Carolina. A cooperative research project with UGA and Dr. Gino D’Angelo, Dr. John Kilgo, and Dr. Stacey Lance began in 2019. Project objectives are: 1) Estimate coyote populations across 3 physiographic regions in South Carolina using fecal genotyping and spatial capture-recapture, 2) Relate coyote population abundance to land use and habitat characteristics across South Carolina, 3) Assess population genetic structure of coyote metapopulations across 3 physiographic regions in South Carolina, 4) Assess food habits of coyotes during fawning and turkey nesting/brood rearing season. Field work on this 3-year study has concluded and analysis is ongoing.
CWD. CWD surveillance continues in SC with an emphasis on targeted surveillance of clinical suspect and high-risk animals. In addition, any illegally possessed or imported deer and other high-risk animals are euthanized and tested for CWD. SCDNR completed a project with Cornell University to develop a CWD risk assessment and surveillance strategy. Based on this project, during 2022 efforts will be directed to enlist the assistance of taxidermists to collect samples.
Tennessee
132,214 deer harvest reports statewide.
Research. Deer Management Unit (DMU) Delineation. TN Tech completed data driven DMU delineation project. The new DMU delineations should be introduced to the Commission in 2024 and, if approved, established in proclamation. Final report available upon request.
Annual Harvest Survey. Since 2019, the University of Tennessee has conducted an annual harvest survey for TWRA. Results from the 2020-21 survey showed that reported harvest accounted for 72% of estimated statewide harvest, down from 78% in 2019-20. The 2021-22 report is available upon request.
Statewide Population Model. Researchers at TN Tech continue to develop an integrated population model (IPM) for deer in TN. The IPM will leverage existing datasets (e.g., reported harvest, field check data, survey harvest estimates, etc.) to estimate populations annually by DMU. Projected completion date is fall 2022.
Adaptive Harvest Management Framework. Researchers at TN Tech are working to develop an adaptive harvest management (AHM) framework to guide decision making when evaluating alternatives being considered to achieve DMU objectives.
Surveillance Optimization for Chronic Wasting Disease (SOP4CWD). TWRA continues to collaborate heavily on the SOP4CWD project led by the Cornell Wildlife Health Lab. See website for more details on this project: cwhl.vet.cornell.edu/project/sop4cwd Deer Density Estimation in CWD-Affected Area. We have continued monitoring impacts of CWD and CWD management in TN by outsourcing thermal aerial surveys on twelve (12) focal areas, each roughly 36 mi2 in size, in west Tennessee.
Trained Canine Detection of Fecal Sample Odor and Whole-Body Odor Associated with CWD Infection. We are partnering with Colorado State University to analyze the ability of biodetectors (i.e., trained dogs) to detect the change in chemical signature of CWD-infected WTD samples. Phase 1 of the project (testing behavioral responses of biodetectors to WTD fecal samples) has been completed, and researchers have had good success in training dogs to correctly identify fecal samples from CWD-infected WTD in both laboratory and controlled field settings. Phase 2 of the project which focuses on laboratory trials of dogs to identify CWD infections from gastrointestinal tract samples began in April 2022, with results forthcoming. Funding provided by USDA-APHIS.
CWD. Surveillance targets were achieved in all 95 counties and were exceeded by a substantial margin in many counties. Finished sampling year with total of 16,193 deer tested. In 2021-22, 634 positives detections. Since the discovery of CWD in December 2018, a total of 1,956 deer have tested positive. Antlered bag limit in Unit CWD increased from 2 to 3 antlered deer. Hunters may take additional antlered deer under CWD incentive programs (e.g., Earn-A-Buck or Replacement Buck programs). The Earn-A-Buck program now requires the hunter to take only one antlerless deer (previously two antlerless deer were required) to receive an additional antlered deer in their bag limit in Unit CWD. The close of the G/M/A (Gun, Muzzleloader, and Archery) deer hunting season in Unit CWD was extended to January 31st .
Texas
2021 estimated statewide harvest was 827,929.
Landowner participation in the 2021 Managed Lands Deer Program (MLDP) represents 10,795 management units on 28,359,488 acres. TPWD issued 363,076 deer tags under the MLDP program in 2021 (142,827 bucks & 220,249 antlerless) and MLDP participants harvested 193,582 white-tailed deer (53.9% of recommended harvest) and 2,206 mule deer (61.3% of recommended harvest).
CWD. 14,523 samples collected in 2021 (11,691 voluntary hunter-harvested samples, 2,606 roadkill samples, 226 other) including 13,546 samples from white-tailed deer, 786 from mule deer, 34 from elk, and 157 from exotic species. 260,748 total CWD test results in Texas 2002-2021 (all sources combined). A total of 370 CWD-positive animals have been detected in Texas since 2012, 77% (n=285) are deer/elk associated with captive breeding facilities and release sites, and the remaining 23% are free range deer and elk.
Virginia
2020-2021 season reported harvest = 191,731; mandatory electronic reporting
Check stations discontinued in fall 2021. All deer reports now electronic (telephone, internet, and eNotch)
Research. Non-baited camera technique for deer population dynamics in Appalachians 2018- 2022, final report received (not public yet)
The Department is being sued by several private property owners over Virginia’s “right to retrieve” law, arguing that allowing hunters to go on their property without their permission to retrieve their hunting dogs amounts to an uncompensated taking of their land and violates the state and federal constitutions.
The Virginia General Assembly passed a bill which will allow hunting on public lands on Sundays beginning in fall 2022. Sunday hunting on private lands was legalized in fall 2014.
The first elk hunt will be held in Virginia’s three county Elk Management Zone (Buchanan, Dickenson, and Wise counties) during October 2022.
CWD. Only one new Virginia CWD positive county, Floyd, was identified/added in 2021. Since CWD was first identified in Virginia in fall 2009, 135 CWD-positive deer have been found in ten counties in Virginia including three in Clarke, two in Culpeper, four in Fauquier, one in Floyd, 104 in Frederick, two in Loudoun, one in Madison, two in Montgomery, one in Rappahannock, 13 in Shenandoah, one in Warren, and one of an unknown location in DMA3.
West Virginia
2021-22 reported deer harvest was 105,278.
Research. Research Survival, Cause-specific Mortality, Resource Selection and Movement of White-tailed Deer in West Virginia. This study has three study areas across the state, including one in a CWD detected County. There are two Ph.D. students, one at West Virginia University (WVU) and one at the University of Georgia, and one Masters student at WVU. A total of 244 deer were captured between the two winter capture seasons, 98 in 2021 and 146 in 2022. To date there are 187 deer alive with GPS collars. The project has recorded 49 mortalities with hunter harvest (n = 15), predation (n = 11), and natural (n = 4) being the top causes. In Hampshire County, three GPS collared deer have died of clinical Chronic Wasting Disease.
Five-year evaluation of Distance Sampling for White-tailed Deer (Odocoileus virginianus) Density Estimation in West Virginia. Dr. H. Brian Underwood, USGS Patuxent Wildlife Research Center, Syracuse Field Station, has completed phase I. Phase II modeling of distance sampling conducted by the WVDNR is ongoing.
Climate Influenced Disease Expansion of Hemorrhagic Disease: West Virginia as a case study. Evaluation of Hemorrhagic Disease (HD) outbreaks across West Virginia from 1981 – 2019. This work is part of a collaboration with Drs. Mark Ruder and David Stallknecht, Southeast Cooperative Wildlife Disease Study, University of Georgia, Sonja Christensen, Department of Fisheries and Wildlife, Michigan State University, and WVDNR personnel.
CWD. As of July 2022, the abnormal prion associated with CWD has been detected in a total of 553 white-tailed deer in West Virginia. Statewide, samples from over 21,000 deer have been tested since 2002 and 495 deer in Hampshire County, 14 from Hardy County, 25 from Berkeley County, 10 from Mineral County, and nine from Morgan County are the only animals found thus far to have the abnormal prion associated with CWD. In the fall of 2021, 299 hunter harvested deer were tested, and the abnormal prion associated with CWD was detected in 51 deer. Year round statewide surveillance outside of the current CWD disease management area has been continuous from 2002 to present.
snip...
2021-22 Arkansas Deer Program Report
Deer Program Coordinator: Ralph Meeker Assistant Deer Program Coordinator: Jeremy Brown
I. Harvest / Population Trends
AR hunters reported harvesting 181,374 deer during the 2021- 22 hunting season. This represents a 16.4% decrease from the record harvest of the 2020-21 season.
The 2021-22 season harvest was a 13-year low.
The 2021-22 harvest consisted of:
o 47.7% antlered bucks (86,556)
o 6.2% button bucks (11,282)
o 46.1% does (83,536)
II. Research
Population-level impacts of chronic wasting disease on Arkansas’s white-tailed deer
This study is being conducted by the University of Georgia. The primary objectives of the study are to estimate the current abundance of white-tailed deer in the CWD management zone; examine survival and recruitment of white-tailed deer in the CWD management zone and to compare these parameters between CWD positive and presumed negative individuals; examine movement and home range size of white-tailed deer within the CWD management zone and to compare these between CWD positive and presumed negative individuals; calculate infection rates of CWD in white-tailed deer by age class and sex, calculate mortality rates and determine causes of mortality for CWD positive and presumed negative white-tailed deer; and lastly to use the above data to populate a model that will examine current and future population trends in the presence of CWD to help inform future management decisions. Researchers began field work in January 2021 and have collared a total of 199 deer (33 bucks, 71 does, and 90 fawns). Of those 199 deer collared, 17 bucks, 47 does, and 23 fawns are still alive as of June 20. They have also established three, 81-camera grids within the study areas that they are actively monitoring.
Screening single nucleotide polymorphisms (SNP) variation to model deer dispersal in Arkansas
This study was completed by the Arkansas Conservation and Molecular Ecology Laboratory at the University of Arkansas. The primary objective was to determine likely origin of seven CWD positive deer collected in FY2022. Two CWD positive WTD were harvested in Randolph and Union counties outside the current CWD zone. The other five CWD positive WTD came from Crawford, Franklin, and Van Buren counties which were already inside the CWD zone but the samples represented the 1 st document cases of CWD in these counties. A total of 144 WTD were assayed for SNP. These data were compared to the existing statewide SNP database comprised of 1,162 WTD collected from 2016-2020. Analyses revealed that all seven WTD most likely originated from within or nearby areas where the samples were collected. These findings highlight the importance of the statewide genetic database of WTD and how it can be leveraged to understand WTD dispersal and inform CWD management efforts.
DMAP Participant Survey
AGFC conducted a DMAP participation survey in May 2022. A response rate of 49.5% was achieved. Three notable points from the survey include 1) overall satisfaction of DMAP was high with the highest level being the quality of harvest report that the clubs receive, 2) the lowest satisfaction rating involved the level of communication received from their respective DMAP biologist, and 3) over 95% of the respondents agreed with the statement “I would recommend the DMAP program to others”.
III. Hot Topics
Harvest Decrease
The 2021-22 season was the second time that Arkansas hunters failed to harvest 200,000+ deer since 2011. However, Arkansas experienced an all-time high deer harvest last season with 216,835. Hunting license sales (resident and non-resident combined) are down by approximately 4.6% from 2021. Deer Management Assistance Program (DMAP) DMAP participation by hunting clubs continues to decrease. This has the potential to significantly impact our biological data sample size. Efforts to implement county-level participation targets have been established via the DMAP SOP. With the creation of a new Private Lands Division within the AGFC, uncertainty of who will take ownership of implementing the program has risen.
Introduction to Hunting College Course Expansion
Many of our agency’s in-person R3 efforts were stalled due to COVID-19 in 2020. Efforts to rebound by recruiting new students for enrollment in the 2021 and 2022 fall classes at both AR Tech University and Black River Technical College have also been impacted due to college enrollment being down and virtual learning still being an option.
Southeastern Deer Partnership
The AGFC is currently participating in the SE Deer Partnership with the USFWS and National Deer Association. Our agency views this as a great partnership opportunity to be able to promote hunting (specifically deer hunting) by communicating its many biological, sociological, and economic impacts IV. Disease Issues / Updates Chronic Wasting Disease See attached page
snip...
Overall, 8,389 samples were tested this sampling season, resulting in 209 CWD positive detections (9 elk and 200 WTD)
Most notable findings of the recent CWD surveillance effort:
5 counties detected their 1st CWD positive WTD this season
Union and Randolph County positives were outside the CWD Zone resulting in Ashley, Bradley, Randolph, and Union Counties being added to the CWD Zone for the 2022-2023 season
Crawford, Franklin, and Van Buren Counties detected their 1st positive samples this season, which have been in the CWD Zone since 2018
Targeted removals were performed at Independence, Randolph, and Union County locations with no additional positives detected
AGFC reached a historical high for samples collected annually
snip...end
Louisiana CWD
III. Hot Topics
Chronic Wasting Disease Detection and Mitigation
Louisiana became the 29th state to detect CWD. The index case was a hunter harvested 8.5 year old buck that also displayed symptoms of the disease. No additional positives have been detected. The next closest detection is 25 miles away in Warren County, MS. Upon confirmation by NVSL, LDWF implemented its CWD response plan. A declaration of emergency was issued prohibiting the use of bait and cervid carcass export. A Notice of Intent has been adopted by the Louisiana Wildlife and Fisheries Commission. Final adoption is pending Legislative oversight by the House and Senate Natural Resource Committees. LDWF utilizes parishes for delineation. Currently, any parish within 25 miles of a positive is included in the CWD Control Area.
Fall 2021, AGFC detected a CWD positive deer 7.5 miles north of Louisiana. A baiting prohibition enacted through declaration of emergency included two adjacent LA parishes. The prohibition was lifted after 300 samples were collected without a detection. Louisiana was struck for the second consecutive year by a Category 4 hurricane. Extensive forest damage occurred over the pine dominated forests of southeast Louisiana. No season closures or modifications were made in response to the storms.
A license restructure was passed in the spring of 2021 by the Louisiana legislature. The changes consolidated the total number of licenses and increased the fees on most privileges. The license and fee restructure effected fishing, hunting and commercial license holders. It was the first fee increase in 20 years for recreational licenses and 35 years for commercial. June 1, 2022 was the start of that license year. While licenses are now valid for 365 days, deer tags are only valid for the season they are issued.
IV. Disease Issues / Updates
Chronic Wasting Disease
LDWF collected 1,602 CWD samples statewide in 2021-22 (13,771 since 2002). CWD regulations have been proposed in response to the January 28th, 2022 CWD detection. Current regulations limiting bait and deer carcass export have been established through declaration of emergency. Final CWD related regulations for the 2022-23 deer season are still pending legislative procedures. Drop off containers will be available within the CWD Control Area. Sample goals are based on a risk based system.
snip...end
Maryland CWD
VIII. Disease Issues/Updates
710 CWD samples were collected in the 2021-2022 season. Of those samples, 53 tested positive for CWD. All CWD positives were detected within the existing disease management area (Allegany and Washington counties).
A total of 133 CWD positive cases have been detected out of 11,592 total samples collected since 1999.
snip...end
Mississippi CWD
Chronic Wasting Disease Mississippi currently has detected 134 CWD positive deer in nine counties. The counties are Benton (87), Marshall (35), Issaquena (2), Alcorn (3), Panola (1), Pontotoc (1), Tallahatchie (1), Tippah (2), and Warren (2).
Notes of interest:
The positives in Mississippi range 220 miles apart.
A 3.5 yo buck captured in December 2020 near our first CWD+ location, outfitted with a GPS collar, swam the MS River in March 2021 (to LA), August 2021 (to MS), and March 2022 (to LA). He is currently about 18 miles from capture site. A doe captured in this same area went 14 miles north in March 2021, back to capture location in June 2021, 22 miles east in March 2022 and did not return.
Plans are underway for a thermal count in January along the MS portion of the Natchez Trace Parkway (about 220 miles).
CWD Positives in Mississippi MAP
snip...end
Missouri CWD
IV. Disease Issues / Updates
Chronic Wasting Disease
• During the 2021-2022 CWD surveillance year, more than 32,000 free-ranging deer were sampled for CWD.
• Nearly 3,100 deer were culled post-hunting season within CWD Core Areas (within 1-2 sq. mi of CWD detections)
• 86 CWD+ deer were detected during the 2021-2022 CWD surveillance year
o 54 CWD+ deer were hunter-harvested and 32 were removed during post-season culling
o First CWD detections in Barry, Christian, Howell, and Washington counties
o Barton, Greene, Ripley, and Vernon counties were added to the CWD Management Zone
• Since 2012, 292 free-ranging CWD+ deer have been detected in Missouri in 22 counties
• For upcoming sampling year:
o Conduct mandatory sampling in 34 of the 38 counties in the CWD Management Zone counties during opening weekend of November portion of firearms deer season
▪ No mandatory sampling in Gasconade, Knox, St. Charles, or Warren counties
o Statewide CWD sample collection by participating taxidermists and meat processors
o Continue targeted culling in CWD Core Areas (January 16 – March 15)
CWD Map
snip...end
North Carolina CWD
Chronic Wasting Disease
Statewide surveillance was increased significantly during the 2021-2022 sampling season following the first detection of CWD in Montgomery County Virginia, just 33 miles from the NC border. The NCWRC Cervid Health Cooperator program was revamped to increase sample collection payments for extracted retropharyngeal lymph nodes from $5 to $15, cooperators were allowed to submit whole heads for $5 each, the 20-sample limit was lifted for cooperating taxidermists, and processors could submit up to 100 samples. In the 2021-2022 sampling season 7,338 deer were tested for CWD, of these 4,895 were collected by Cervid Health Cooperators
-Confirmed CWD positive
In late March of 2022, NCWRC was notified that CWD was detected in a sample from a buck that had been harvested in northern Yadkin Co. in December 2021 and submitted by a taxidermist in the Cervid Health Cooperator Program. The positive was confirmed by the National Veterinary Services Laboratory on March 31st. An investigation of the deer was executed, and the cooperative hunter showed biologists and wildlife law enforcement to the location of harvest as well as trail camera photos of the deer days before he was killed. The buck was estimated at 2.5 years old, and a DNA sample removed from the skull mount provided by the hunter was matched with DNA extracted from the positive lymph node in the lab.
snip...end
Oklahoma CWD
???
no mention of it, see my latest Oklahoma CWD update at the bottom of this report;
South Carolina CWD
III. Hot Topics
Things have generally been quiet in South Carolina. Pushback from urine manufacturers related to the 2019 regulation prohibiting the use of commercially available natural deer lures briefly resurfaced in 2021. SCDNR’s position is that until AFWA modifies its CWD BMP’s the regulation will remain in place.
IV. Disease Issues / Updates
snip...
Chronic Wasting Disease
CWD surveillance continues in SC with an emphasis on targeted surveillance of clinical suspect and high-risk animals. In addition, any illegally possessed or imported deer and other high-risk animals are euthanized and tested for CWD. SCDNR completed a project with Cornell University to develop a CWD risk assessment and surveillance strategy. Based on this project, during 2022 efforts will be directed to enlist the assistance of taxidermists to collect samples. All deer hunters in South Carolina receive physical deer tags by mail which provides a platform for messaging related to the CWD carcass importation and commercial urine ban regulations that are in place. The carcass importation messaging is unique for residents and nonresidents.
snip...end
Tennessee CWD
Chronic Wasting Disease
Surveillance 2021-22
Surveillance targets were achieved in all 95 counties and were exceeded by a substantial margin in many counties.
Finished sampling year with total of 16,193 deer tested.
In 2021-22, 634 positives detections. Since the discovery of CWD in December 2018, a total of 1,956 deer have tested positive.
Crockett, Gibson, McNairy, and Hardin Counties went from “High Risk CWD Counties” to “Positive CWD Counties”.
We also detected CWD in Weakley, Henry, Hardin, and Dyer Counties, making them positive counties.
Due to the proximity to these positives (i.e., within 10 miles), Carroll, Decatur, Lake, and Obion Counties became high risk counties.
Wayne County also became high risk due to the proximity of recent detection of CWD in Lauderdale County, AL.
After the 2021-22 deer hunting season, Fayette County had the highest county-wide prevalence (number tested/number positive) of CWD at 17.8% and Hardeman County had the next highest at 11.9%.
Both Fayette County and Hardeman County have seen increases in prevalence since 2018.
The remaining Positive CWD Counties all had a prevalence below 2%.
19 elk sampled in East TN (all not detected).
Strategic Planning Efforts
Tennessee’s Chronic Wasting Disease Management and Response Plan (2023-2027) has been drafted and is nearing final edits. The plan will then go out to review from partners and for public comment before presentation to the commission.
Targeted Removal
Second targeted removal effort for CWD occurred during Winter ’22.
Removals conducted by USDA Wildlife Services. Landowner recruitment conducted primarily by TWRA.
100 deer removed over the 4 removal zones.
Planning efforts underway to increase the number of deer removed in Winter ‘23.
Surveillance 2022-23
Buffer Zone will expand to include Hardin, Decatur, Dyer, Carroll, Lake, Obion, and Wayne Counties.
Freezer drop-off locations and processor/taxidermist incentive program to be expanded into these counties.
Rest of state will have similar targets as 2021-22.
Regulation changes for 2022-23 season
Antlered bag limit in Unit CWD increased from 2 to 3 antlered deer. Hunters may take additional antlered deer under CWD incentive programs (e.g., Earn-A-Buck or Replacement Buck programs)
The Earn-A-Buck program now requires the hunter to only take one antlerless deer (previously two antlerless deer were required) to receive an additional antlered deer in their bag limit in Unit CWD.
The close of the G/M/A (Gun, Muzzleloader, Archery) deer hunting season in Unit CWD was extended to January 31st .
Carcass transportation and feeding restrictions still in effect for Positive CWD Countiesa and High Risk CWD Countiesb .
For more information go to CWDinTN.com
snip...end
Texas CWD
Texas Deer Program Report 2022
Alan Cain
IV. Disease Issues / Updates
Chronic Wasting Disease
• New CWD zone proposed in Duval County
• CWD positive breeding facility depopulated in Duval County (May 2022) / 1 additional positive confirmed.
• CWD positive breeding facility in Hunt County has not been depopulated. TPWD working through litigation / courts to find resolution
• Statewide Surveillance
o 14,523 samples collected in 2021 (11,691 voluntary hunter-harvested samples, 2,606 roadkill samples, 226 other)
o 13,546 samples from white-tailed deer, 786 from mule deer, 34 from elk, and 157 from exotic species
o Females represented 41.5% and males 57.4% of total samples, 1.1% sex was unknown
o 110,495 CWD tests (“Not Detected” / “Detected”) from TPWD collected samples 2002-2021
• Private Samples
o 55,490 postmortem / 65,611 ante mortem deer breeder tests 2002-2021
o 18,532 postmortem deer breeder release site tests 2015-2021
o 10,720 TTT & TTP permit postmortem tests (2002-2021)
• 260,748 total CWD test results in Texas 2002-2021 (all sources combined)
A total of 370 CWD-positive animals have been detected in Texas since 2012, 77% (n=285) are deer/elk associated with captive breeding facilities and release sites, and the remaining 23% are free range deer and elk (Table 1).
Table 1. CWD positives by CWD zone, species (WTD, MD, Elk, Red Deer), and source (fr – free range, cp – captive pen, cr – captive release site). Positives are summarized by calendar year in which the date of the positive was confirmed.
CWD Zone Species 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Total
Trans Pecos MD (fr) 6 0 1 1 5 2 4 2 8 6 4 39
Panhandle
MD (fr) 0 0 0 1 2 2 1 7 3 7 0 23
Elk (fr) 0 0 0 0 1 0 0 0 0 0 0 1
WTD (fr) 0 0 0 0 0 1 3 0 1 1 0 6
South-Central Texas
WTD (fr) 0 0 0 0 1 0 1 3 3 1 3 12
WTD (cp) 0 0 0 5 21 21 45 19 1 46 71 229
WTD (cr) 0 0 0 1 2 4 6 1 6 0 2 22
Elk (cr) 0 0 0 0 0 1 1 0 0 1 0 3
Red Deer (cr) 0 0 0 0 0 0 0 1 1 0 1 2
Val Verde WTD (fr) 0 0 0 0 0 0 0 2 1 0 0 3
Kimble WTD (cp) 0 0 0 0 0 0 0 0 10 0 0 10
WTD (cr) 0 0 0 0 0 0 0 0 0 0 2 2
Hunt WTD (cp) 0 0 0 0 0 0 0 0 0 8 3 11
Matagorda WTD (cp) 0 0 0 0 0 0 0 0 0 1 0 1
Mason WTD (cp) 0 0 0 0 0 0 0 0 0 1 0 1
Lubbock MD (fr) 0 0 0 0 0 0 0 0 0 1 0 1
Duval WTD (cp) 0 0 0 0 0 0 0 0 0 2 1 3
Grand Total 6 0 1 8 31 31 61 34 35 65 97 370
snip...end
Virginia CWD
IV. Disease Issues / Updates
Chronic Wasting Disease (CWD)
Virginia did not identify any new totally unexpected CWD counties or areas in 2021 (see Figure 2). Previously, CWD surveillance efforts had identified big unexpected jumps in CWD to Culpeper County in fall 2018 and to Montgomery County in fall 2020. Only one new Virginia CWD positive county, Floyd, was identified/added in 2021. The new CWD positive deer in Floyd in 2021 was within five miles of the original CWD positive deer in Montgomery from fall 2020. Floyd County was already included in Disease Management Area (DMA) 3.
In DMA1, the original CWD area centered in and around Frederick and northern Shenandoah counties (Disease Management Area 1 (DMA1)) continues to grow and expand. First detected in fall 2009 near the community of Gore in Frederick County on the West Virginia state border, CWD has been moving east across Frederick County and south for a decade and has now become established in the western two thirds of Frederick County and the northern half of Shenandoah County. CWD surveillance efforts in DMA1 have been reduced in recent years.
In DMA2, created in fall 2019 and expanded in fall 2020 and which is that area east of DMA1, isolated and mostly disjunct cases of CWD continue to be identified annually. In four years of surveillance, ten positive deer have been identified in DMA2.
In DMA3, created in fall 2021, surveillance efforts picked up three new CWD positives. In four years of surveillance, four positive deer have been identified in DMA3.
In addition to the three DMAs noted above, the Department continues to conduct annual statewide CWD surveillance using a taxidermist-supported surveillance strategy. In fall 2021, approximately 2,175 samples from hunter-harvested deer were submitted by participating taxidermists.
Since CWD was first identified in Virginia in fall 2009, 135 CWD-positive deer have been found in ten counties in Virginia including three in Clarke, two in Culpeper, four in Fauquier, one in Floyd, 104 in Frederick, two in Loudoun, one in Madison, two in Montgomery, one in Rappahannock, 13 in Shenandoah, one in Warren, and one of an unknown location in DMA3.
see map Figure 2 2021 CWD status in Virginia...
snip...end
West Virginia CWD
IV. Disease Issues
Chronic Wasting Disease
As of July 2022, the abnormal prion associated with CWD has been detected in a total of 553 white-tailed deer in West Virginia (Figure 2).
Statewide, samples from over 21,000 deer have been tested since 2002 and 495 deer in Hampshire County, 14 from Hardy County, 25 from Berkeley County, 10 from Mineral County, and nine from Morgan County are the only animals found thus far to have the abnormal prion associated with CWD.
In the fall of 2021, 299 hunter harvested deer were tested and the abnormal prion associated with CWD was detected in 51 deer.
Year round statewide surveillance outside of the current CWD disease management area has been continuous from 2002 to present.
Figure 2: Panel A is 2021 hunter harvest samples with CWD detection status. Panel B depicts all detected CWD positive deer from 2005 to present.
***> END <***
source reverence
SEAFWA COMMITTEE Cervid Working Group Report August 16, 2022 CWD TSE Prion Report, no url available that i could find, this report was sent to me...terry
SOUTHEASTERN ASSOCIATION OF FISH AND WILDLIFE AGENCIES WILDLIFE RESOURCES COMMITTEE
Cervid Working Group Report July 14, 2021
Meeting Convened: July 14, 09:30 EDT
snip...
State Report Highlights (see attached state reports for additional information)
Alabama
• 218,358 deer harvested during 2019-2020 deer season (estimated from hunter phone survey); up 7.5% from 2018-2019 season
• Participating in Surveillance Optimization Project for Chronic Wasting Disease • Suspect HD cases reported in 26 of 67 counties
• 2,120 CWD samples collected from wild deer during 2020-2021; no detections thus far
Arkansas
• Record deer harvest during 2020-2021 season (~216,800)
• Research project being conducted within CWD Management Zone
• Hired first captive wildlife coordinator
• Updated White-tailed Deer Strategic Management Plan
• Update to CWD Management and Response Plan approved by Commission
• Past CWD surveillance year: 8 CWD+ elk; 261 CWD+ whitetails
o Grand totals since first detection: 32 CWD+ elk; 1,081 CWD+ whitetails
Florida
• Second year of mandatory harvest reporting
• Research project in north FL to study population dynamics
• Rule prohibiting importation of deer carcasses (except certain parts) from out of state
• Working on preparation for and response if/when CWD is detected
• Have collected >16,500 CWD samples since 2002; no detections yet
• Working on developing hazard model for CWD detection
Georgia
• 2020-2021 deer harvest (~209,100) slightly more than in 2019-2020
• 231,000 acres impacted by Deer Management Assistance Program thus far
• Low fawn recruitment rates observed
• Collected 1,357 CWD samples in 2020-2021; no CWD detections to date
• Fawn mortality study conducted on Chattahoochee National Forest
5
Kentucky
• ~141,600 deer harvested during 2020-2021 deer season (down 5% from previous year)
• Conducting deer hunter survey
• Deer population slowly rebounding in areas of eastern KY (HD outbreak in 2017)
• Considerable increases in harvest during crossbow season
• >35,000 deer and 805 elk samples tested for CWD since 2002; no detections yet
Louisiana
• Estimated harvest of 191,800 deer from mail survey (2nd highest in past 10 seasons)
• Five named storms struck LA last year; harvest down 25% in SW Louisiana
• License restructure passed in spring of 2021
• 12,169 CWD samples tested since 2002; not detections to date
• Analysis of forest structure and plant species composition in areas of recent flooding
Maryland
• Harvest up 3% from 2019-2020 deer season
• Conducting survey of sika deer hunters
• Research project upcoming to study sika deer demographics and movements
• Studying deer movements in Montgomery County
• Straight-walled rifle cartridges permitted during firearms deer season in counties where only shotguns have been permitted in past
• ~350 suspect HD cases reported
• 10,882 CWD samples collected since 1999; 80 CWD+ detections
Mississippi
• Harvest up 19% from the 2019-2020 season; 12% increase in deer hunters
• Numerous research projects including influence of fire season and intensity on plant communities, buck movement response to hunting activity and supplemental feeding, and effects of supplemental feeding on sources of disease and habitat
• 4th year of flooding in south Delta
• CWD Response Plan updated/changed to CWD Management Plan
• Have detected 83 CWD+ deer in eight counties
• Several regulation changes within CWD Management Zone
Missouri
• 5th highest harvest on record
• Record archery season harvest; increasing percentage of kill by crossbows
• Research to evaluate effects of CWD targeted culling and increase understanding of landowner motivation and barriers to participating in targeted culling
• Expansion of Deer Management Assistance Program
• Changes to confined cervid regulations
6
• 44 new CWD+ detections; brings total to 206 CWD+ deer since 2012
North Carolina
• Harvest up 9% from previous three-year average
• Research project studying deer ecology across urban-rural continuum
• Over 487 suspect cases of HD; most in Northwestern Zone
• Have tested nearly 17,200 CWD samples to date; no detections
• Commission to vote on revised CWD Response Plan
• CWD+ detection in VA 33 miles from NC border
Oklahoma
• Harvest record of 126,290 deer
• Highest antlerless deer harvest in five years
• Possible research project regarding Pronghorn success
• ODWC Foundation considering elk relocation project in south-central OK
• CWD+ in KS within 11 miles of OK border
South Carolina
• Harvest up 2% from 2019; 38% below record harvest in 2002
• 6% increase in deer hunter numbers
• 4th season of “all deer” tagging system and statewide antlered buck limit
• Conducting doe and fawn movement and survival study
• Field work for three-year coyote study completed
• CWD Response Plan updated; no CWD+ detections to date
Tennessee
• Harvest up ~19% from 2019-2020 deer season; up 36% in CWD Unit
• Project to delineate Deer Management Units
• Working on integrated population model to estimate populations annually by DMU
• Estimated deer density on eight focal areas in CWD Unit
• 18,735 deer tested for CWD last year; 644 positives; total to date is 1,322 CWD+ deer
• Conducted targeted removal effort for CWD last winter
• Several regulation changes within CWD Unit
Texas
• Harvest (~852,450) up ~1% from 2019-2020 season
• Research project on public perceptions of CWD in western Texas
• Developing pilot program for digital licenses and electronic tagging
• Collected 13,154 CWD samples in 2020; total number samples ~208,000 since 2002
• 258 CWD+ detections since 2012
• CWD detected in 5 new captive facilities since March 2021 (297 trace facilities)
7
Virginia
• ~209,000 deer harvested
• Deer hunting license sales up ~7% over last two years, but down over 30% the past 25 years
• Research: Non-baited camera technique for deer population dynamics in Appalachians
• Adopted three resolutions regarding hunting deer with dogs
• All electronic harvest registration beginning this fall
• First elk season to be held fall 2022
• High occurrence of HD last year
• 110 CWD+ detections since 2009 (10 counties)
West Virginia
• Harvest (106,861) up 7.5% from 2019-2020 season
• Research: Deer survival, cause-specific mortality, resource selection, and movements
• Five-year evaluation of distance sampling for deer density estimation
• Revision of White-tailed Deer Operation Plan (2020-2025)
• >21,000 deer tested for CWD since 2002; 463 CWD+ detections to date
snip...
NOW, an update review on these states for CWD to date;
TUESDAY, MARCH 08, 2022
Alabama Second Case of CWD Confirmed in Northwest
THURSDAY, OCTOBER 20, 2022
Arkansas Chronic Wasting Disease CWD TSE Prion Update 1,345+ Cases Confirmed To Date
SATURDAY, FEBRUARY 05, 2022
Louisiana, NVSL Confirms first case of CWD TSE PrP in WTD
THURSDAY, MAY 19, 2022
Maryland DNR reported that 53 WTD sampled within Allegany and Washington counties in 2021 tested positive for chronic wasting disease CWD
THURSDAY, MARCH 10, 2022
Mississippi CWD TSE Prion 2022 Samples Shows 38 Positive To Date
THURSDAY, OCTOBER 20, 2022
North Carolina Deer Herd Third Detection of CWD Confirmed
Oklahoma CWD
MONDAY, SEPTEMBER 12, 2022
OKLAHOMA ODWC ACTIVATES CWD RESPONSE PLAN AFTER DISEASED DEER FOUND WITHIN MILES OF PANHANDLE
Tennessee CWD
Tennessee Chronic Wasting Disease CWD High Prevalence Rate Ames Plantation
Attitudes and Behavior of Deer Hunting Club Members Following Discovery of
Chronic Wasting Disease
Mark A. Turner1, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996
Bonner L. Powell, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996
Neelam C. Poudyal, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996
Allan E. Houston, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Grand Junction, TN 38039 Bronson K. Strickland, Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Starkville, MS 39762 Craig A. Harper, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996
Abstract: Chronic wasting disease (CWD) is a fatal neurological disease that affects cervid species including white-tailed deer (Odocoileus virginianus). As of 2021, it occurs in seven southeastern states, and more discoveries in the region are likely to occur. Hunter education regarding CWD is critical to obtain support for disease management actions that rely on hunter participation but potentially are in opposition to typical hunter objectives. In August 2018, we provided educational programming on CWD to 84 members of a deer hunting club in west Tennessee. After CWD was discovered in the immediate area of the club in December 2018, in spring 2019 we surveyed the attitudes and hunting behaviors of club members. When surveyed five months following discovery of CWD, 86% of respondents expressed extreme or moderate concern about CWD. The number of total deer sightings was the most important factor influencing hunter satisfaction for 70% of respondents. Reducing deer density often is used to reduce CWD prevalence rates, but 66% of respondents did not support such reductions. Despite our efforts to educate hunters and, once CWD was detected, to encourage hunters to maintain or increase harvest, doe harvest declined by 78% during the 2019 deer season. Understanding attitudes and harvest behaviors of hunters is essential to managing CWD. Hunting clubs in the southeastern United States may provide important opportunities for outreach and education before and after CWD is discovered in their areas. Our survey indicates hunter concern about CWD is great, and state wildlife agencies likely will need to de- velop effective educational strategies to maintain or increase doe harvest if the disease is discovered.
Snip...
The major decline in membership that occurred at Ames Plantation likely was driven by high CWD prevalence rates.
In 2019, 13 of the 21 bucks harvested were CWD positive, for a prevalence rate of 62%.
Doe prevalence rate in 2019 was 21% (7/33 tested), still relatively high given that 45% of the does tested were younger than 3.5 years old.
In 2020, the prevalence rate among bucks was 66%(27/41), and the doe prevalence rate was 22.5% (18/80).
These highprevalence rates and the spatial distribution of CWD in Tennessee suggest CWD likely was present at Ames Plantation for many years prior to discovery and highlights the importance of testing to detect the disease before hunters face such high prevalence rates (Jennelle et al. 2014).
We find it noteworthy that mature buck sightings and harvest had not declined following such high disease prevalence, but it is possible they would decline subsequently if management strategies were not changed.
TUESDAY, JULY 19, 2022
Tennessee CWD-Positive Deer Confirmed in Dyer County, Obion County, Lake County Become High-Risk
Texas CWD
SATURDAY, SEPTEMBER 24, 2022
Texas Chronic Wasting Disease Confirmed at a Limestone County Deer Breeding Facility
To date, 392 captive or free-ranging cervids, including white-tailed deer, mule deer, red deer and elk, in 16 Texas counties have tested positive for CWD.
see Texas CWD History;
Counties where CWD Exposed Deer were Released
Number of CWD Exposed Deer Released by County
Virginia CWD
WEDNESDAY, MARCH 09, 2022
Virginia Summary DWR’s 2021–2022 deer hunting season CWD surveillance in the Disease Management Areas (DMA) Finds 25 More Positives
West Virginia
FRIDAY, AUGUST 13, 2021
West Virginia DNR CWD TSE Prion CWD has been found in 451 white-tailed deer to date
PRION CONFERENCE 2022 ABSTRACTS CWD TSE PrP ZOONOSIS
Transmission of prion infectivity from CWD-infected macaque tissues to rodent models demonstrates the zoonotic potential of chronic wasting disease.
Samia Hannaouia, Ginny Chenga, Wiebke Wemheuerb, Walter J. Schulz-Schaefferb, Sabine Gilcha, and Hermann M. Schätzla aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine & Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bInstitute of Neuropathology, Medical Faculty, Saarland University, Homburg/Saar, Germany
Aims: Chronic wasting disease (CWD) is a prion disease of cervids. Its rapid geographic expansion, shedding of infectivity and persistence in the environment for many years are of concern for humans. Here, we provide the first evidence by transmission experiments to different transgenic mouse models and bank voles that Cynomolgus macaques inoculated via different routes with CWD-positive cervid tissues harbor infectious prions that elicit clinical disease in rodents.
Material and Methods: We used tissue materials from macaques inoculated with CWD to inoculate transgenic mice overexpressing cervid PrPCfollowed by transmission into bank voles. We used RT-QuIC, immunoblot and PET blot analysis to assess brains, spinal cords, and tissues of the gastrointestinal tract (GIT) for the presence of prions.
Results: Our results show that of the macaque materials that induced clinical disease in transgenic mice,73% were from the CNS (46% spinal cord and 27% brain), and 27% were from the spleen, although attack rates were low around 20%. Clinical mice did not display PK-resistant PrPSc(PrPres) in immunoblot, but showed low-levels of prion seeding activity. Transmission into bank voles from clinical transgenic mice led to a 100% attack rate with typical PrPressignature in immunoblot, which was different from that of voles inoculated directly with CWD or scrapie prions. High-level prion seeding activity in brain and spinal cord and PrPresdeposition in the brain were present. Remarkably, we also found prion seeding activity in GIT tissues of inoculated voles. Second passage in bank voles led to a 100% attack rate in voles inoculated with brain, spinal cord and small intestine material from first round animals, with PrPresin immunoblot, prion seeding activity, and PrPresdeposition in the brain. Shortened survival times indicate adaptation in the new host. This also shows that prions detected in GIT tissues are infectious and transmissible. Transmission of brain material from sick voles back to cervidized mice revealed transmission in these mice with a 100% attack rate, and interestingly, with different biochemical signature and distribution in the brain.
Conclusions: Our findings demonstrate that macaques, considered the best model for the zoonotic potential of prions, were infected upon CWD challenge, including oral one. The disease manifested as atypical in macaques and transgenic mice, but with infectivity present at all times, as unveiled in the bank vole model with an unusual tissue tropism.
Funded by: The National Institutes of Health, USA, and the Alberta Prion Research Institute/Alberta Innovates Canada. Grant number: 1R01NS121016-01; 201,600,023
Acknowledgement: We thank Umberto Agrimi, Istituto Superiore di Sanità, Rome, Italy, and Michael Beekes, Robert-Koch Institute Berlin, Germany, for providing the bank vole model. We thank the University of Calgary animal facility staff and Dr. Stephanie Anderson for animal care.
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
Samia Hannaouia, Irina Zemlyankinaa, Sheng Chun Changa, Maria Immaculata Arifina, Vincent Béringueb, Debbie McKenziec, Hermann M. Schatzla, and Sabine Gilcha
aDepartment of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada; bUniversité Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France; cDepartment of Biological Sciences, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
Aims: Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we aimed to determine the zoonotic potential of CWD using a mouse model for human prion diseases.
Material and Methods: Transgenic mice overexpressing human PrPChomozygous for methionine at codon 129 (tg650) were inoculated intracerebrally with brain homogenates of white-tailed deer infected with Wisc-1/CWD1 or 116AG CWD strains. Mice were monitored for clinical signs and were euthanized at terminal disease. Brains were tested by RT-QuIC, western blot upon PK digestion, and immunohistochemistry; fecal homogenates were analyzed by RT-QuIC. Brain/spinal cord and fecal homogenates of CWD-inoculated tg650 mice were inoculated into tg650 mice or bank voles. Brain homogenates of bank voles inoculated with fecal homogenates of CWD-infected tg650 mice were used for second passage in bank voles.
Results: Here, we provide the strongest evidence supporting the zoonotic potential of CWD prions, and their possible phenotype in humans. Inoculation of mice expressing human PrPCwith deer CWD isolates (strains Wisc-1 and 116AG) resulted in atypical clinical manifestations in > 75% of the mice, with myoclonus as leading clinical sign. Most of tg650 brain homogenates were positive for seeding activity in RT-QuIC. Clinical disease and presentation was transmissible to tg650 mice and bank voles. Intriguingly, protease-resistant PrP in the brain of tg650 mice resembled that found in a familial human prion disease and was transmissible upon passage. Abnormal PrP aggregates upon infection with Wisc-1 were detectable in thalamus, hypothalamus, and midbrain/pons regions.
Unprecedented in human prion disease, feces of CWD-inoculated tg650 mice harbored prion seeding activity and infectious prions, as shown by inoculation of bank voles and tg650 with fecal homogenates.
Conclusions: This is the first evidence that CWD can infect humans and cause disease with a distinctive clinical presentation, signature, and tropism, which might be transmissible between humans while current diagnostic assays might fail to detect it. These findings have major implications for public health and CWD-management.
Funded by: We are grateful for financial support from the Natural Sciences and Engineering Research Council of Canada, the National Institutes of Health, Genome Canada, and the Alberta Prion Research Institute. SG is supported by the Canada Research Chairs program.
Acknowledgement: We thank Dr. Trent Bollinger, WCVM, University of Saskatchewan, Saskatoon, Canada, for providing brain tissue from the WTD-116AG isolate, Dr. Stéphane Haïk, ICM, Paris, France, for providing brain tissue from vCJD and sCJD cases, and Dr. Umberto Agrimi, Istituto Superiore di Sanità, Italy, for the bank vole model. We thank animal facility staff for animal care, Dr. Stephanie Anderson for veterinary oversight, and Yo-Ching Cheng for preparing recombinant PrP substrates. Thank you to Dr. Stephanie Booth and Jennifer Myskiw, Public Health Agency of Canada, Canada.
The chronic wasting disease agent from white-tailed deer is infectious to humanized mice after passage through raccoons
Eric Cassmanna, Xu Qib, Qingzhong Kongb, and Justin Greenleea
aNational Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, IA, USA bDepartments of Pathology, Neurology, National Center for Regenerative Medicine, and National Prion Disease Pathology Surveillance Center, Case Western Reserve University, Cleveland, Ohio, USA
Aims: Evaluate the zoonotic potential of the raccoon passaged chronic wasting disease (CWD) agent in humanized transgenic mice in comparison with the North American CWD agent from the original white-tailed deer host.
Material and Methods: Pooled brain material (GG96) from a CWD positive herd was used to oronasally inoculate two white-tailed deer with wild-type prion protein genotype and intracranially inoculate a raccoon. Brain homogenates (10% w/v) from the raccoon and the two white-tailed deer were used to intracranially inoculate separate groups of transgenic mice that express human prion protein with methionine (M) at codon 129 (Tg40h). Brains and spleens were collected from mice at experimental endpoints of clinical disease or approximately 700 days post-inoculation. Tissues were divided and homogenized or fixed in 10% buffered neutral formalin. Immunohistochemistry, enzyme immunoassay, and western blot were used to detect misfolded prion protein (PrPSc) in tissue.
Results: Humanized transgenic mice inoculated with the raccoon passaged CWD agent from white-tailed deer exhibited a 100% (12/12) attack rate with an average incubation period of 605 days. PrPScwas detected in brain tissue by enzyme immunoassay with an average optical density of 3.6/4.0 for positive brains. PrPScalso was detected in brain tissue by western blot and immunohistochemistry. No PrPScwas detected in the spleens of mice inoculated with the raccoon passaged CWD agent. Humanized mice inoculated with the CWD agent from white-tailed deer did not have detectable PrPScusing conventional immunoassay techniques.
Conclusions: The host range of the CWD agent from white-tailed deer was expanded in our experimental model after one passage through raccoons.
Funded by: This research was funded in its entirety by congressionally appropriated funds to the United States Department of Agriculture, Agricultural Research Service. The funders of the work did not influence study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Acknowledgement: We thank Quazetta Brown, Lexi Frese, Rylie Frese, Kevin Hassall, Leisa Mandell, and Trudy Tatum for providing excellent technical support to this project.
Stable and highly zoonotic cervid prion strain is possible
Manuel Camacho, Xu Qi, Liuting Qing, Sydney Smith, Jieji Hu, Wanyun Tao, Ignazio Cali, and Qingzhong Kong Department of Pathology, Case Western Reserve University, Cleveland, USA
Aims: Whether CWD prions can infect humans remains unclear despite the very substantial scale and long history of human exposure of CWD in some areas. Multiple in vitro conversion experiments and in vivo animal studies suggest that the CWD-to-human transmission barrier is not unbreakable. A major public health concern on CWD zoonosis is the emergence of highly zoonotic CWD strains. We aim to address the question of whether highly zoonotic CWD strains are possible.
Material and Methods: We inoculated a few sCJD brain samples into cervidized transgenic mice, which were intended as negative controls for bioassays of brain tissues from sCJD cases who had hunted or consumed vension from CWD-endemic states. Some of these mice became infected and their brain tissues were further examined by serial passages in humanized or cervidized mice.
Results: Passage of sCJDMM1 in transgenic mice expressing elk PrP (Tg12) resulted in a ‘cervidized’ CJD strain that we termed CJDElkPrP. We observed 100% transmission of CJDElkPrPin transgenic mice expressing human PrP (Tg40h). We passaged CJDElkPrPtwo more times in the Tg12 mice. We found that such second and third passage CJDElkPrPprions also led to 100% infection in the Tg40h mice. In contrast, we and others found zero or poor transmission of natural elk CWD isolates in humanized mice, despite that natural elk CWD isolates and CJDElkPrPshare the same elk PrP sequence.
Conclusions: Our data demonstrate that highly zoonotic cervid prion strains are not only possible but also can be stably maintained in cervids and that CWD zoonosis is prion strain-dependent.
Funded by: NIH
Grant number: R01NS052319, R01NS088604, R01NS109532
Acknowledgement: We want to thank the National Prion Disease Pathology Surveillance Center and Drs. Allen Jenny and Katherine O’Rourke for providing the sCJD samples and the CWD samples, respectively.
Adaptation of chronic wasting disease (CWD) prion strains in hosts with different PRNP genotypes
Camilo Duque Velasqueza,c, Elizabeth Triscotta,c, Chiye Kima,c, Diana Morenoa,c, Judd Aikenb,c, and Debbie McKenziea,c
aDepartment of Biological Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; bDepartment of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB T6G 2G8, Canada; cCentre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
Aims: The contagious nature of CWD epizootics and the PrPCamino acid variation of cervids (and susceptible sympatric species) guarantee the expansion of prion conformational diversity and selective landscapes where new strains can arise. CWD strains can have novel transmission properties including altered host range that may increase zoonotic risk as circulating strains diversify and evolve. We are characterizing the host adaptability of characterized CWD strains as well as CWD isolates from different cervid species in various enzootic regions.
Material and Methods: Characterized CWD strains as well as a number of isolates from hunter-harvested deer were bioassayed in our rodent panel (transgenic mice expressing cervid alleles G96, S96 and H95-PrPC, elk PrPC, bovine PrPC, and both hamsters and non-transgenic laboratory mice). Strain characteristics were compared using computer based scoring of brain pathology (e.g. PrPCWDbrain distribution), western blot and protein misfolding cyclic amplification (PMCA).
Results: Transmission of various isolates resulted in the selection of strain mixtures in hosts expressing similar PrPC, particularly for polymorphic white-tailed deer and for Norwegian reindeer. As of the second passage, transmission of P153 moose prions from Norway has not resulted in emergence of strains with properties similar to any North American CWD strains in our taxonomic collection (Wisc-1, CWD2, H95+and 116AG).
Conclusions: Our data indicates polymorphic white-tailed deer can favor infection with more than one strain. Similar to transmission studies of Colorado CWD isolates from cervids expressing a single PrPCprimary structure, the isolate from Norway reindeer (V214) represents a strain mixture, suggesting intrinsic strain diversity in the Nordfjella epizootic. The diversity of CWD strains with distinct transmission characteristics represents a threat to wildlife, sympatric domestic animals and public health.
Funded by: Genome Canada and Genome Alberta (Alberta Prion Research Institute and Alberta Agriculture & Forestry); NSERC Grant number: #LSARP 10205; NSERC RGPIN-2017-05539
Acknowledgement: We would like to thank Margo Pybus (Alberta Environment and Parks) Trent Bollinger (University of Saskatchewan) for providing us with tissue samples from hunter-harvested deer and Sylvie Benestad for providing moose and reindeer samples.
Application of PMCA to understand CWD prion strains, species barrier and zoonotic potential
Sandra Pritzkowa, Damian Gorskia, Frank Ramireza, Fei Wanga, Glenn C. Tellingb, Justin J. Greenleec, Sylvie L. Benestadd, and Claudio Sotoa aDepartment of Neurology, University of Texas Medical School at Houston, Houston, Texas, USA; bDepartment of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA; cVirus and Prion Research Unit, United States Department of Agriculture, Ames, Iowa, USA; dNorwegian Veterinary Institute, OIE Reference Laboratory for CWD, Ås, Norway
Aims: Chronic wasting disease (CWD) is a prion disease affecting various species of cervids that continues to spread uncontrollably across North America and has recently been detected in Scandinavia (Norway, Sweden and Finland). The mechanisms responsible for the natural transmission of CWD are largely unknown. Furthermore, the risk of CWD transmission to other species, including humans, is also unknown and remains a dangerous enigma. In this study, we investigated the potential of CWD prions to infect several other animal species (sheep, cattle, pig, hamster, and mouse) including humans, by examining their capacity to convert the normal prion protein of distinct species in a PMCA reaction. Moreover, we also investigated whether the in vivo passage of CWD through intermediate species alters their capacity for zoonotic transmission, which may represent a major hazard to human health.
Material and Methods: For these studies, we used brain material from CWD-infected white-tailed deer (Odocoileus virginianus), elk (Cervus canadensis), and mule deer (Odocoileus hemionus) as species native to North America. We also used CWD-infected Moose (Alces alces), reindeer (Rangifer tarandus) and red deer (Cervus elaphus) as Norwegian cervids. We also used brains from cattle, sheep and pigs experimentally infected by CWD. To study interspecies-transmission and zoonotic potential, samples were tested via PMCA for the conversion of PrPCinto PrPScusing different combinations of inoculum and host species. Based on these analyses we estimated the spillover and zoonotic potential for different CWD isolates. We define and quantify spillover and zoonotic potential indices as the efficiency by which CWD prions sustain prion generation in vitro at the expense of normal prion proteins from various mammals and human, respectively.
Results: Our results show that prions from some cervid species, especially those found in Northern Europe, have a higher potential to transmit disease characteristics to other animals. Conversely, CWD-infected cervids originated in North America appear to have a greater potential to generate human PrPSc. We also found that in vivo transmission of CWD to cattle, but not to sheep or pigs substantially increases the ability of these prions to convert human PrPCby PMCA.
Conclusions: Our findings support the existence of different CWD prion strains with distinct spillover and zoonotic potentials. We also conclude that transmission of CWD to other animal species may increase the risk for CWD transmission to humans. Our studies may provide a tool to predict the array of animal species that a given CWD prion could affect and may contribute to understanding the risk of CWD for human health.
Funded by: National Institute of Health Grant number: P01 AI077774
Generation of human chronic wasting disease in transgenic mice
Zerui Wanga, Kefeng Qinb, Manuel V. Camachoa, Ignazio Cali a,c, Jue Yuana, Pingping Shena, Tricia Gillilanda, Syed Zahid Ali Shaha, Maria Gerasimenkoa, Michelle Tanga, Sarada Rajamanickama, Anika Yadatia, Lawrence B. Schonbergerd, Justin Greenleee, Qingzhong Konga,c, James A. Mastriannib, and Wen-Quan Zoua,c
aDepartment of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, USA; bDepartment of Neurology and Center for Comprehensive Care and Research on Memory Disorders, the University of Chicago Pritzker School of Medicine, Chicago, USA; cNational Prion Disease Pathology Surveillance Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; dDivision of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA, USA; eVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA, USA
Aims: Chronic wasting disease (CWD) results from the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC) in the brains of deer and elk. It has been spreading rapidly throughout many regions of North America, exported inadvertently to South Korea, and more recently identified in Europe. Mad cow disease has caused variant Creutzfeldt-Jakob disease (vCJD) in humans and is currently the only known zoonotic prion disease. Whether CWD is transmissible to humans remains uncertain. The aims of our study were not only to confirm whether CWD prion isolates can convert human brain PrPCinto PrPScin vitro by serial protein misfolding cyclic amplification (sPMCA) but also to determine whether the sPMCA-induced CWD-derived human PrPScis infectious.
Material and Methods: Eight CWD prion isolates from 7 elks and 1 deer were used as the seeds while normal human brain homogenates containing either PrP-129 MM (n = 2) or PrP-129 VV (n = 1) were used as the substrates for sPMCA assay. A normal elk brain tissue sample was used as a negative control seed. Two lines of humanized transgenic (Tg) mice expressing either human PrP-129VV or −129 MM polymorphism were included for transmission studies to determine the infectivity of PMCA-amplified PrPSc. Wester blotting and immunohistochemistry and hematoxylin & eosin staining were used for determining PrPScand neuropathological changes of inoculated animals.
Results: We report here the generation of the first CWD-derived infectious human PrPScusing elk CWD PrPScto initiate conversion of human PrPCfrom normal human brain homogenates with PMCA in vitro. Western blotting with a human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPScwas derived from the human brain PrPCsubstrate. Two lines of humanized transgenic mice expressing human PrPCwith either Val or Met at the polymorphic codon 129 developed clinical prion disease following intracerebral inoculation with the PMCA-generated CWD-derived human PrPSc. Diseased mice exhibited distinct PrPScpatterns and neuropathological changes in the brain.
Conclusions: Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSchas the potential to overcome the species barrier and directly convert human PrPCinto infectious PrPScthat can produce bona fide prion disease when inoculated into humanized transgenic mice.
Funded by: CJD Foundation and NIH
Mortality surveillance of persons potentially exposed to chronic wasting disease
R.A. Maddoxa, R.F. Klosb, L.R. Willb, S.N. Gibbons-Burgenerb, A. Mvilongoa, J.Y. Abramsa, B.S. Applebyc, L.B. Schonbergera, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bWisconsin Department of Health Services (WDHS), Division of Public Health, Madison, USA; cNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: It is unknown whether chronic wasting disease (CWD), a prion disease of cervids, can infect people, but consumption of meat from infected animals would be the most likely route of transmission. Wisconsin Department of Health Services, Division of Public Health (WDHS) personnel maintain a database consisting of information collected from hunters who reported eating, or an intention to eat, venison from CWD-positive cervids. These data, collected since 2003, allow for the evaluation of causes of mortality in individuals potentially exposed to CWD.
Material and Methods: The WDHS database contains the name, date of birth, when available, year of CWD-positive deer harvest, and city and state of residence for each potentially exposed individual. The database also includes information on how the deer was processed (self-processed or by a commercial operator) and when applicable, names of others with whom the venison was shared. Duplicate entries (i.e., those who consumed venison from CWD-positive deer in multiple hunt years) are determined by first name, last name, and date of birth. All names in the database are cross-checked with reported cases of human prion disease in Wisconsin and cases in the National Prion Disease Pathology Surveillance Center (NPDPSC) diagnostic testing database. Persons with date of birth available are also cross-checked with prion disease decedents identified through restricted-use national multiple cause-of-death data via a data use agreement with the National Center for Health Statistics (NCHS).
Results: The database currently consists of 1561 records for hunt years 2003–2017 and 87 additional records for 2018–2019. Of these, 657 records have accompanying date of birth; 15 entries were removed as duplicates leaving 642 unique individuals. Of these individuals, 278 of 426 (66%) who ate venison from a CWD-positive deer and provided processing information reported self-processing. No matches were found among any persons in the database cross-checked with WDHS human prion disease surveillance data, NPDPSC data (February 2022 update), and NCHS data through 2020.
Conclusions: Because of the linkage of person and CWD-positive animal in the WDHS database, reviewing the cause of mortality in potentially exposed persons is possible. The number of individuals cross-checked so far is likely only a small percentage of those potentially exposed to CWD in Wisconsin, and many more years of vital status tracking are needed given an expected long incubation period should transmission to humans occur. Nevertheless, the findings of this ongoing review are thus far reassuring.
Prion disease incidence, United States, 2003–2020
R.A. Maddoxa, M.K. Persona, K. Kotobellib, A. Mvilongoa, B.S. Applebyb, L.B. Schonbergera, T.A. Hammetta, J.Y. Abramsa, and E.D. Belaya aNational Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, USA; bNational Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University, Cleveland, USA
Aims: Mortality data, in conjunction with neuropathological and genetic testing results, are used to estimate prion disease incidence in the United States.
Material and Methods: Prion disease decedents for 2003–2020 were identified from restricted-use U.S. national multiple cause-of-death data, via a data use agreement with the National Center for Health Statistics, and from the National Prion Disease Pathology Surveillance Center (NPDPSC) database. NPDPSC decedents with neuropathological or genetic test results positive for prion disease for whom no likely match was found in the NCHS multiple cause-of-death data were added as cases for incidence calculations, while those with negative neuropathology results but with cause-of-death data indicating prion disease were removed. Unmatched cases in the NPDPSC database lacking neuropathological testing but with a positive real-time quaking-induced conversion (RT-QuIC) test result were additionally assessed. Age-specific and age-adjusted average annual incidence rates were calculated from the combined data; the year 2000 as the standard population and the direct method were used for age-adjustment.
Results: A total of 7,921 decedents were identified as having prion disease during 2003–2020 for an age-adjusted average annual incidence of 1.2 per million population. The age-adjusted incidence between males and females (1.3 and 1.1 per million, respectively) differed significantly (p < 0.0001). The age-specific average annual incidence among those <55 and ≥55 years of age was 0.2 and 4.8 per million, respectively; incidence among those ≥65 was 6.1 per million. Eighteen cases were <30 years of age for an age-specific incidence of 8.0 per billion; only 6 of these very young cases were sporadic (3 sporadic CJD, 3 sporadic fatal insomnia), with the rest being familial (9), variant (2), or iatrogenic (1). The age-adjusted annual incidence for the most recent year of data, 2020, was 1.3 per million. However, assessment of RT-QuIC positive cases lacking neuropathology in the NPDPSC database suggested that approximately 20% more cases may have occurred in that year; the addition of a subset of these cases that had date of death information available (n = 44) increased the 2020 rate to 1.4 per million.
Conclusions: Mortality data supplemented with the results of neuropathological, CSF RT-QuIC, and genetic testing can be used to estimate prion disease incidence. However, the identification in the NPDPSC database of RT-QuIC-positive cases lacking date of death information suggests that this strategy may exclude a number of probable prion disease cases. Prion disease cases <30 years of age, especially those lacking a pathogenic mutation, continue to be very rare.
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported.
Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques.
Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas.
Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA
Grant number: AP20VSSPRS00C143
ATYPRION project: assessing the zoonotic potential of interspecies transmission of CWD isolates to livestock (preliminary results).
Enric Vidala,b, Juan Carlos Espinosac, Samanta Gilera,b, Montserrat Ordóñeza,b, Guillermo Canteroa,b, Vincent Béringued, Justin J. Greenleee, and Juan Maria Torresc
aUnitat mixta d’Investigació IRTA-UAB en Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; bIRTA. Programa de Sanitat Animal. Centre de Recerca en Sanitat Animal (CReSA). Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia; cCentro de Investigación en Sanidad Animal, CISA-INIA-CSIC, Valdeolmos, Madrid, Spain; dMolecular Virology and Immunology, French National Research Institute for Agriculture, Food and Environment (INRAE), Université Paris-Saclay, Jouy-en-Josas, France; eVirus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, USA
Aims: Since variant Creutzfeldt-Jackob disease was linked to the consumption of bovine spongiform encephalopathy prions, the study of the pathobiological features of animal prions, particularly their zoonotic potential, is of great concern to the scientific community and public health authorities. Furthermore, interspecies transmission of prions has been demonstrated as a putative evolutionary mechanism for prions, that can lead to the emergence of new features including the ability to infect humans. For instance, small ruminants’ atypical scrapie prions, when propagated in a bovine or porcine host, can shift to a classical BSE phenotype thus posing a potential risk in case of human exposure. So far, no hard evidence of zoonotic transmission of cervids’ chronic wasting disease (CWD) to humans has been published, however experimental transmission to bovine, ovine and caprine hosts has been achieved. Our goal is to investigate if, once passaged through these domestic species, CWD prions might become infectious to humans.
Material and Methods: Different CWD isolates experimentally adapted to cattle, sheep and goat (Hamir et al, 2005, 2006, 2007, Greenlee et al 2012) have been intracerebrally inoculated to transgenic mouse models expressing the human cellular prion protein either homozygous for methionine or valine at codon 129 (Tg340-Met129 and Tg362-Val129). Additionally, inocula obtained from experimental transmission of elk CWD to ovinized (Tg501) and bovinized (BoTg110) transgenic mice, as well as white-tailed deer CWD to BoTg110 mice, are currently being bioassayed in both human PrPCtransgenic models.
Results and conclusions: No evidence of transmission has been found on first passage for bovine adapted elk and mule deer CWD to none of the humanized models. The remaining bioassays are ongoing without showing clinical signs yet, as well as second passages for the negative 1stpassages.
Funded by: La Marató de TV3 foundation. Grant number: ATYPRION (201,821–30-31-32)
PRION CONFERENCE 2022 ABSTRACTS CWD TSE PrP ZOONOSIS and ENVIRONMENTAL FACTORS
Chronic wasting disease detection in environmental and biological samples from a taxidermy site
Paulina Sotoa,b, J. Hunter Reedc, Mitch Lockwoodc, and Rodrigo Moralesa,b aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile; cTexas Parks and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy affecting captive and free-ranging cervids (e.g., mule deer, white-tailed deer, elk, reindeer, and moose). Nowadays, CWD is widely distributed in North America. It is suggested that CWD spreads due to direct animal contact or through exposure to contaminated environments previously inhabited by infected animals. CWD may also be spread through the movement of infected animals and carcasses. Taxidermy practices involve processing deer tissues (or whole animal carcasses). In many cases, the CWD status of processed animals is unknown. This can generate risks of disease spread and transmission. Taxidermy practices include different steps involving physical, chemical, and biological procedures. Without proper tissue handling or disposal practices, taxidermist facilities may become a focus of prion infectivity. Aims: In this study, we evaluated the presence of infectious prions in a taxidermy facility believed to be exposed to CWD. Detection was performed using the Protein Misfolding Cyclic Amplification (PMCA) technique in biological and inert environmental samples. Methods: We collected biological and environmental samples (plants, soils, insects, excreta, and others) from a taxidermy facility, and we tested these samples using the PMCA technique. In addition, we swabbed different surfaces possibly exposed to CWD-infected animals. For the PMCA reaction, we directly used a swab piece or 10 µL of 20% w/v homogenized samples. Results: The PMCA analysis demonstrated CWD seeding activity in some of the components of this facility, including insects involved in head processing, soils, and a trash dumpster. Conclusions: Different areas of this property were used for various taxidermy procedures. We were able to detect the presence of prions in i) soils that were in contact with the heads of dead animals, ii) insects involved in the cleaning of skulls, and iii) an empty dumpster where animal carcasses were previously placed. This is the first report demonstrating that swabbing is a helpful method to screen for prion infectivity on surfaces potentially contaminated with CWD. These findings are relevant as this swabbing and amplification strategy may be used to evaluate the disease status of other free-ranging and captive settings where there is a concern for CWD transmissions, such as at feeders and water troughs with CWD-exposed properties. This approach could have substantial implications for free-ranging cervid surveillance as well as in epidemiological investigations of CWD.
Funded by: USDA Grant number: AP20VSSPRS00C143
Large-scale PMCA screening of retropharyngeal lymph nodes and in white-tailed deer and comparisons with ELISA and IHC: the Texas CWD study
Rebeca Benaventea, Paulina Sotoa, Mitch Lockwoodb, and Rodrigo Moralesa aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bTexas Park and Wildlife Department, Texas, USA
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that affects various species of cervids, and both free-ranging and captive animals. Until now, CWD has been detected in 3 continents: North America, Europe, and Asia. CWD prevalence in some states may reach 30% of total animals. In Texas, the first case of CWD was reported in a free-range mule deer in Hudspeth and now it has been detected in additional 14 counties. Currently, the gold standard techniques used for CWD screening and detection are ELISA and immunohistochemistry (IHC) of obex and retropharyngeal lymph nodes (RPLN). Unfortunately, these methods are known for having a low diagnostic sensitivity. Hence, many CWD-infected animals at pre-symptomatic stages may be misdiagnosed. Two promising in vitro prion amplification techniques, including the real-time quaking-induced conversion (RT-QuIC) and the protein misfolding cyclic amplification (PMCA) have been used to diagnose CWD and other prion diseases in several tissues and bodily fluids. Considering the low cost and speed of RT-QuIC, two recent studies have communicated the potential of this technique to diagnose CWD prions in RPLN samples. Unfortunately, the data presented in these articles suggest that identification of CWD positive samples is comparable to the currently used ELISA and IHC protocols. Similar studies using the PMCA technique have not been reported. Aims: Compare the CWD diagnostic potential of PMCA with ELISA and IHC in RPLN samples from captive and free-range white-tailed deer. Material and Methods: In this study we analyzed 1,003 RPLN from both free-ranging and captive white-tailed deer collected in Texas. Samples were interrogated with the PMCA technique for their content of CWD prions. PMCA data was compared with the results obtained through currently approved techniques. Results: Our results show a 15-fold increase in CWD detection in free-range deer compared with ELISA. Our results unveil the presence of prion infected animals in Texas counties with no previous history of CWD. In the case of captive deer, we detected a 16% more CWD positive animals when compared with IHC. Interestingly, some of these positive samples displayed differences in their electroforetic mobilities, suggesting the presence of different prion strains within the State of Texas. Conclusions: PMCA sensitivity is significantly higher than the current gold standards techniques IHC and ELISA and would be a good tool for rapid CWD screening.
Funded by: USDA Grant number: AP20VSSPRS00C143
Protein misfolding cyclic amplification (PMCA) as an ultra-sensitive technique for the screening of CWD prions in different sample types
Francisca Bravo‐Risia,b, Paulina Sotoa,b, Rebeca Benaventea, Hunter Reedc, Mitch Lockwoodc, Tracy Nicholsd, and Rodrigo Moralesa,b aDepartment of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA; bCentro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago, Chile; cTexas Park and Wildlife Department, Texas, USA; dVeterinary Services Cervid Health Program, United States Department of Agriculture, Animal and Plant Health Inspection Service, Fort Collins, Colorado, USA
Chronic wasting disease (CWD) is a prion disease that affects farmed and free-ranging cervids. The infectious agent in CWD is a misfolded form of the prion protein (PrPSc) that promotes conformational changes in the host’s cellular prion protein (PrPC). Currently, definitive CWD status is confirmed in the brain and lymphoid tissues by immunohistochemistry. The limitation of this technique is its poor sensitivity. Protein misfolding cyclic amplification (PMCA) and real-time quaking-induced conversion (RT- QuIC) are ultra-sensitive techniques that overcome these issues. PMCA mimics the self- propagation of infectious prions in vitro through multiple incubation/sonication cycles, increasing the number of prion particles present in a given sample. The detection of proteinase K (PK) -resistant PrPScby PMCA has been performed in experimental and natural samples that might harbor subclinical levels of prions. These samples include several tissues, bodily fluids, excreta, and different manmade and natural materials, including mineral licks, soils, and plants. Aims: In this study, we highlight recent advances and contributions that our group has performed in the detection of CWD prions from samples collected in farmed and free-ranging cervids, as well as other specimens involving the environment that contains CWD-infected deer. Material and Methods: A set of diverse samples analyzed in this study were collected by USDA and TPWD personnel in breeding and taxidermy facilities, and deer breeding facilities. These included animal and environmental samples. Additional samples from free-ranging animals were provided by hunters. Results: The diverse range of samples successfully detected for CWD prion infection in this study include blood, semen, feces, obex, retropharyngeal lymph node, fetuses (neural and peripheral tissues) and gestational tissues, parasites, insects, plants, compost/soil mixtures, and swabs from trash containers. Importantly, these results helped to identify seeding-competent prions in places reported to be free of CWD. The levels of prion infectivity in most of these samples are currently being investigated. Conclusions: Our findings contribute to the understanding of the transmission dynamics and prevalence of CWD. In addition, our data have helped to identify CWD in areas previously considered to be free of CWD. We also demonstrate that PMCA is a powerful technique for the screening of biological and environmental samples. Overall, our research suggests that PMCA may be a useful tool to implement for the surveillance and management of CWD. Funded by: NIH/NIAID and USDA Grant number: 1R01AI132695 (NIH) and AP20VSSPRS00C143 (USDA)
Nasal bot: an emerging vector for natural chronic wasting disease transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Carlos Kramma, Nelson Pereza, Rebeca Benaventea, J. Hunter Reedc, Mitch Lockwoodc, Tracy A. Nicholsd, and Rodrigo Moralesa,b aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile; cTexas Park and Wildlife Department, Texas, USA; dVeterinary Services Cervid Health Program, United States Department of Agriculture, Animal and Plant Health Inspection Service, Fort Collins, Colorado, USA
Chronic wasting disease (CWD) is a fatal neurodegenerative disease that affects farmed and free-ranging cervids populations. The spread of CWD in cervids is thought to occur through the direct contact between cervids or through the exposure of naïve animals to contaminated environments. Parasites are known vectors of multiple diseases in animals. However, the potential role of parasites in CWD transmission remains unclear. Aims: The main objective of this study was to determine if CWD prions could be detected in the larvae of deer nasal bot flies, a common deer parasite, taken from CWD-infected white-tailed deer (Odocoileus virginianus). Methods: Bot fly larvae were collected from the nasal cavity of naturally infected CWD- positive or CWD non-detect white-tailed deer. The CWD seeding activity of the larvae was interrogated by PMCA. Prion infectivity was also evaluated in cervidized transgenic mouse bioassay (intra-cerebral administration in Tg1536 mice). Mice inoculated with bot larvae homogenate were sacrificed when they showed established signs of prion disease, or at extended periods after treatment (600 days). All inoculated mouse brains were evaluated for protease resistant prions to confirm clinical or sub-clinical infection. Bot larvae from CWD non-detect deer were used as controls. To further mimic environmental transmission, bot larvae homogenates were mixed with soils and plants were grown on them. Both plants and soils were tested for prion seeding activity. Results: PMCA analysis demonstrated CWD seeding activity in nasal bot larvae from captive and free-ranging white-tailed deer. CWD-contaminated bots efficiently infected transgenic mice, with attack rates and incubation periods suggesting high infectivity titers. Further analyses of treated animals (biochemical characterization of protease resistant prions and immunohistochemistry) confirmed prion infection. Analyses on dissected parts of the bot larvae demonstrate that the infectivity is concentrated in the larvae cuticle (outer part). Nasal bot larvae extracts mixed with
soils showed seeding activity by PMCA. Interestingly, plants grown in soil contaminated with the nasal bot larvae extract were found to produce seeding activity by PMCA. Conclusion: In this study we described for the first time that deer nasal bot larvae from CWD-infected deer carry high CWD infectivity titers. We also demonstrate that CWD prions in these parasites can interact with other environmental components relevant for disease transmission. Considering this information, we propose that deer nasal bot larvae could act as vectors for CWD transmission in wild and farming settings. Funded by: NIH/NIAID and USDA/APHIS Grant number: R01AI132695 and AP20VSSPRS00C143 PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
Shedding of Chronic Wasting Disease Prions in Multiple Excreta Throughout Disease Course in White-tailed Deer
Nathaniel D. Denkersa, Erin E. McNultya, Caitlyn N. Krafta, Amy V. Nallsa, Joseph A. Westricha, Wilfred Goldmannb, Candace K. Mathiasona, and Edward A. Hoovera
aPrion Research Center, College of Veterinary Medicine and Biological Sciences, Department of Microbiology, Immunology, and Pathology; Colorado State University, Fort Collins, CO, USA; bDivision of Infection and Immunity, The Roslin Institute and the Royal Dick School of Veterinary Studies, University of Edinburgh, Midlothian, UK
Aims: Chronic wasting disease (CWD) now infects cervids in South Korea, North America, and Scandinavia. CWD is unique in its efficient transmission and shedding of prions in body fluids throughout long course infections. Questions remain as to the magnitude of shedding and the route of prion acquisition. As CWD continues to expand, the need to better understand these facets of disease becomes more pertinent. The purpose of the studies described was to define the longitudinal shedding profile of CWD prions in urine, saliva, and feces throughout the course of infection in white-tailed deer.
Material and Methods: Twelve (12) white-tailed deer were inoculated with either 1 mg or 300ng of CWD. Urine, saliva, and feces were collected every 3-month post-inoculation (MPI) throughout the study duration. Cohorts were established based on PNRP genotype: codon 96 GG (n = 6) and alternate codons 96 GS (n = 5) & 103NT (n = 1). Urine and saliva were analyzed using iron-oxide magnetic extraction (IOME) and real-time quaking induced conversion (RT-QuIC)(IQ). Feces were subjected to IOME, followed by 4 rounds protein misfolding cyclic amplification (PMCA) with products analyzed by RT-QuIC (IPQ). To determine whether IPQ may be superior to IQ, a subset of urine and saliva were also tested by IPQ. Results were compared with clinical disease status.
Results: Within the 96 GG cohort, positive seeding activity was detected in feces from all deer (100%), in saliva from 5 of 6 (83%), and in urine from 4 of 6 (66%). Shedding in all excreta occurred at, or just after, the first positive tonsil biopsy result. In the 96 GS/103NT cohort, positive seeding activity could be detected in feces from 3 of 6 (50%) deer, saliva in 2 of 6 (33%), and urine in 1 of 6 (16%). Shedding in excreta was detected >5 months after the first tonsil positive result. Four of six 96 GG deer developed clinical signs of CWD, whereas only 2 of the 96 GS/103NT did. Shedding was more frequently detected in deer with clinical disease. The IPQ protocol did not significantly improve detection in saliva or urine samples, however, it significantly augmented detection in feces by eliminating non-specific background commonly experienced with IQ. Negative control samples remained negative in samples tested.
Conclusions: These studies demonstrate: (a) CWD prion excretion occurs throughout infection; (2) PRNP genotype (GG≫GS/NT) influences the excreta shedding; and (3) detection sensitivity in excreta can vary with different RT-QuIC protocols. These results provide a more complete perspective of prion shedding in deer during the course of CWD infection.
Funded by: National Institutes of Health (NIH)
Grant number: RO1-NS061902-09 R to EAH, PO1-AI077774 to EAH, and R01-AI112956-06 to CKM
Acknowledgement: We abundantly thank Sallie Dahmes at WASCO and David Osborn and Gino D’Angelo at the University of Georgia Warnell School of Forestry and Natural Resources for their long-standing support of this work through provision of the hand-raised, CWD-free, white-tailed deer used in these studies
Carrot plants as potential vectors for CWD transmission
Paulina Sotoa,b, Francisca Bravo-Risia,b, Claudio Sotoa, and Rodrigo Moralesa,b
aDepartment of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Texas, USA; bUniversidad Bernardo O’Higgins, Santiago, Chile
Prion diseases are infectious neurodegenerative disorders afflicting humans and other mammals. These diseases are generated by the misfolding of the cellular prion protein into a disease-causing isoform. Chronic wasting disease (CWD) is a prevalent prion disease affecting cervids (captive and free-range). CWD is thought to be transmitted through direct animal contact or by indirect exposure to contaminated environments. Many studies have shown that infectious prions can enter the environment through saliva, feces, or urine from infected animals and decaying carcasses. However, we do not fully understand the specific contribution of each component to disease transmission events. Plants are logical environmental components to be evaluated since they grow in environments contaminated with CWD prions and are relevant for animal and human nutrition.
Aims: The main objective of this study is to study whether prions are transported to the roots and leaves of carrots, an edible plant commonly used in the human diet and as deer bait.
Methods: We have grown carrot plants in CWD-infected soils. After 90 days, we harvested the carrots and separated them from the leaves. The experiment was controlled by growing plants in soil samples treated with brain extracts from healthy animals. These materials were interrogated for their prion seeding activity using the Protein Misfolding Cyclic Amplification (PMCA) technique. Infectivity was evaluated in mouse bioassays (intracerebral injections in Tg1536 mice). The animals were sacrificed when they showed established signs of prion disease. Animals not displaying clinical signs were sacrificed at 600 days post-inoculation.
Results: The PMCA analysis demonstrated CWD seeding activity in soils contaminated with CWD prions, as well as in carrot plants (leaves and roots) grown on them. Bioassays demonstrated that both leaves and roots contained CWD prions in sufficient quantities to induce disease (92% attack rate). As expected, animals treated with prion-infected soils developed prion disease at shorter incubation periods (and complete attack rates) compared to plant components. Animals treated with soil and plant components exposed with CWD-free brain extracts did not display prion-associated clinical signs or evidence of sub-clinical prion infection.
Conclusions: We show that edible plant components can absorb prions from CWD contaminated soils and transport them to their aerial parts. Our results indicate that plants could participate as vectors of CWD transmission. Importantly, plants designated for human consumption represent a risk of introducing CWD prions into the human food chain.
Funded by: NIH
Grant number: R01AI132695
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies
Location: Virus and Prion Research
Title: Transmission of the atypical/nor98 scrapie agent to suffolk sheep with VRQ/ARQ, ARQ/ARQ, and ARQ/ARR genotypes
Author item Cassmann, Eric item MAMMADOVA, JAJIBA - Orise Fellow item BENESTAD, SYLVIE - Norwegian Veterinary Institute item MOORE, SARA JO - Orise Fellow item Greenlee, Justin
Submitted to: PLoS ONE Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/21/2021 Publication Date: 2/11/2021
Citation: Cassmann, E.D., Mammadova, J., Benestad, S., Moore, S., Greenlee, J.J. 2021. Transmission of the atypical/nor98 scrapie agent to suffolk sheep with VRQ/ARQ, ARQ/ARQ, and ARQ/ARR genotypes. PLoS ONE. 16(2). Article e0246503. https://doi.org/10.1371/journal.pone.0246503. DOI: https://doi.org/10.1371/journal.pone.0246503
Interpretive Summary: Atypical scrapie is a prion disease that affects sheep. Unlike classical scrapie, atypical scrapie is thought to occur spontaneously, and it is unlikely to transmit between sheep under natural conditions. Another notable distinction between classical and atypical scrapie is the prion protein genotype of afflicted sheep and the locations in the brain where misfolded prions accumulate. Atypical scrapie generally occurs in sheep that are resistant to classical scrapie. Misfolded prions are predominantly found in the cerebellum for atypical scrapie and not in the brainstem as seen with classical scrapie. Atypical scrapie is a relevant disease because of its potential association with other prion diseases. Some research has shown that the atypical scrapie agent can undergo a transformation of disease forms that makes it appear like classical scrapie or classical bovine spongiform encephalopathy (mad cow disease). Therefore, atypical scrapie is thought to be a possible source for these prion diseases. We investigated the transmission of the atypical scrapie agent to sheep with three different prion protein genotypes. A diagnosis of atypical scrapie was made in all three genotypes of sheep. Misfolded prion protein was detected earliest in the cerebellum and the retina. This is the first report describing the early accumulation of misfolded prions in the retina of sheep with atypical scrapie. Understanding where misfolded prions accumulate in cases of atypical scrapie can lead to better detection earlier in the disease. Furthermore, the materials derived from this experiment will aid in investigating origins of other prion diseases.
Technical Abstract: Scrapie is a transmissible spongiform encephalopathy that occurs in sheep. Atypical/Nor98 scrapie occurs in sheep with that tend to be resistant to classical scrapie and it is thought to occur spontaneously. The purpose of this study was to test the transmission of the Atypical/Nor98 scrapie agent in three genotypes of Suffolk sheep and characterize the distribution of misfolded prion protein (PrPSc). Ten sheep were intracranially inoculated with brain homogenate from a sheep with Atypical/Nor98 scrapie. All sheep with the ARQ/ARQ and ARQ/ARR genotypes developed Atypical/Nor98 scrapie confirmed by immunohistochemistry, and one (1/3) sheep with the VRQ/ARQ genotype had detectable PrPSc consistent with Atypical/Nor98 scrapie at the experimental endpoint of 8 years. Sheep with mild early accumulations of PrPSc in the cerebellum had concomitant retinal PrPSc. Accordingly, large amounts of retinal PrPSc were identified in clinically affected sheep and sheep with dense accumulations of PrPSc in the cerebellum.
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
Title: Scrapie in white-tailed deer: a strain of the CWD agent that efficiently transmits to sheep?
Author item Greenlee, Justin item KOKEMULLER, ROBYN - US Department Of Agriculture (USDA) item MOORE, S - Oak Ridge Institute For Science And Education (ORISE) item WEST GREENLEE, M - Iowa State University
Submitted to: Meeting Abstract Publication Type: Abstract Only Publication Acceptance Date: 3/29/2019 Publication Date: N/A Citation: N/A
Interpretive Summary:
Technical Abstract: Scrapie is a transmissible spongiform encephalopathy 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 the tissue distribution of PrPSc in affected cervids is similar to scrapie in sheep. There are several lines of evidence that suggest that multiple strains of CWD exist, which may affect the agent’s potential to transmit to hosts of the same or different species. We inoculated white-tailed deer with the scrapie agent from ARQ/ARQ sheep, which resulted in 100% attack rates by either the intracranial or oronasal route of inoculation. When examining tissues from the brainstems or lymphoid tissues by traditional diagnostic methods such as immunohistochemistry or western blots, it is difficult to differentiate tissues from deer infected with scrapie from those infected with CWD. However, there are several important differences between tissues from scrapie-infected white-tailed deer (WTD scrapie) and those infected with CWD (WTD CWD). First, there are different patterns of PrPSc deposition in the brains of infected deer: brain tissues from deer with WTD scrapie had predominantly particulate and stellate immunoreactivity whereas those from deer with WTD-CWD had large aggregates and plaque-like staining. Secondly, the incubation periods of WTD scrapie isolates are longer than CWD isolates in mice expressing cervid prion protein. Most notably, the transmission potential of these two isolates back to sheep is distinctly different. Attempts to transmit various CWD isolates to sheep by the oral or oronasal routes have been unsuccessful despite observation periods of up to 7 years. However, WTD scrapie efficiently transmitted back to sheep by the oronasal route. Upon transmission back to sheep, the WTD scrapie isolate exhibited different phenotypic properties when compared to the sheep receiving the original sheep scrapie inoculum including different genotype susceptibilities, distinct PrPSc deposition patterns, and much more rapid incubation periods in transgenic mice expressing the ovine prion protein. The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identication of CWD strains in deer and the eradication of scrapie from sheep.
''The scrapie agent readily transmits between sheep and deer after oronasal exposure. This could confound the identication of CWD strains in deer and the eradication of scrapie from sheep.''
RT-QuIC detection of pathological prion protein in subclinical goats following experimental oral transmission of L-type BSE
Alessandra Favole1* , Maria Mazza1 , Antonio D’Angelo2 , Guerino Lombardi3 , Claudia Palmitessa1 , Luana Dell’Atti1 , Giulia Cagnotti2 , Elena Berrone1 , Marina Gallo1 , Tiziana Avanzato1 , Erika Messana1 , Loretta Masoero1 , Pier Luigi Acutis1 , Daniela Meloni1 , Franco Cardone4 , Maria Caramelli1 , Cristina Casalone1 and Cristiano Corona1*
Abstract
Objective: The spread of bovine spongiform encephalopathy (BSE) agent to small ruminants is still a major issue in the surveillance of transmissible spongiform encephalopathies (TSEs). L-type bovine spongiform encephalopathy (L-BSE) is an atypical form of BSE with an unknown zoonotic potential that is transmissible to cattle and small ruminants. Our current knowledge of bovine atypical prion strains in sheep and goat relies only on experimental transmission studies by intracranial inoculation. To assess oral susceptibility of goats to L-BSE, we orally inoculated five goats with cattle L-BSE brain homogenates and investigated pathogenic prion protein (PrPsc) distribution by an ultrasensitive in vitro conversion assay known as Real-Time Quaking Induced Conversion (RT-QuIC).
Results: Despite a prolonged observation period of 80 months, all these animals and the uninfected controls did not develop clinical signs referable to TSEs and tested negative by standard diagnostics. Otherwise, RT-QuIC analysis showed seeding activity in five out of five examined brain samples. PrPsc accumulation was also detected in spinal cord and lymphoreticular system. These results indicate that caprine species are susceptible to L-BSE by oral transmission and that ultrasensitive prion tests deserve consideration to improve the potential of current surveillance systems against otherwise undetectable forms of animal prion infections.
snip...
Discussion and conclusions
Data here presented indicate that caprine species are susceptible to L-BSE after oral administration and are able to produce very low levels of prions in both lymphatic and central nervous tissues as demonstrated by optimized, high-sensitive, RT-QuIC assay.
At variance with goats intracerebrally infected with L-BSE [4], in this study, no animal developed clinical signs of disease despite prolonged periods of observation, suggesting a comparatively low efficiency of the oral route versus the intracerebral one in L-BSE, a feature that further distinguish this strain from classical BSE [14, 15].
Interestingly, all goats tested negative by standard diagnostics for PrPsc performed on brainstem. This finding, associated with the low amount of PrPsc detected in different brain areas, suggests a partial strain-specific transmission barrier. Indeed, inoculation of a prion into a new host species can produce prolonged incubation periods and/or subclinical infection [16, 17]. In addition, the lack of clinical signs suggests that naturally L-BSE-infected goats may be asymptomatic similarly to what proposed by Okada et al. for oral L-BSE in cattle [17].
In line with previous results [18], RT-QuIC detected lower levels of prions than traditional diagnostic tools. Rapid and confirmatory tests failed to identify any PrPsc in the subclinical animals, while RT-QuIC allowed us to detect misfolded prion protein in multiple brain regions, spinal cord and lymphoreticular system. Studies have established that the rate of fluorescence increase in RTQuIC, while not measuring infectivity, is directly related to the concentration of prions in the sample seeding the reaction [19, 20]. Prolonged lag phases of RT-QuIC reactions indicate relatively low amounts of PrPsc in the examined tissues and may reassure about the possibility of goat to play as silent L-BSE spreaders in natural conditions. However, we believe that prudence must be always adopted when dealing with the risk of prion spread in field conditions as also suggested by recent data by Denkers and colleagues, who showed that the oral route of infection for chronic wasting disease in deer, may be much more efficient than previously thought [21]. Furthermore, although the mere presence of PrPsc is not indicative of a possible infectivity of the tissue, the finding of positivity in the lymphoreticular tissue must alert to the potential distribution of PrPsc in peripheral body regions which may increase the risks for humans. Bioassay of infectivity by inoculation of susceptible animals with brains of these goats may help to clarify this issue.
Based on the results achieved with this prion form and also other animal strains, it would be useful to consider the possibility to enlarge current diagnostic criteria to include, in defined conditions (e.g. very limited amounts of source tissue, or preclinical testing), the application of ultrasensitive diagnostic methods. This will not only improve the sensitivity of our surveillance systems but will also help to protect food chain from accidental spillovers of the agent of L-BSE.
Limitations
Te primary limitation of this work is that infectivity was not demonstrated by bioassay and the infectious titre was not determined. Terefore, we cannot comment the degree of risk for human.
Despite these limitations, this work specifcally demonstrates prion-seeding activity in tissues of goats orally exposed to L-BSE and provide RT-QuIC as useful method to enhance surveillance of TSEs.
Keywords: Prion, L-BSE, RT-QuIC, Goat, Oral transmission, PrPsc, Ultrasensitive detection
snip...see full text;
WEDNESDAY, MARCH 16, 2022
SHEEP BY-PRODUCTS AND WHAT ABOUT Scrapie TSE PrP and Potential Zoonosis?
SO, WHO'S UP FOR SOME MORE TSE PRION POKER, WHO'S ALL IN $$$
SO, ATYPICAL SCRAPIE ROUGHLY HAS 50 50 CHANCE ATYPICAL SCRAPIE IS CONTAGIOUS, AS NON-CONTAGIOUS, TAKE YOUR PICK, BUT I SAID IT LONG AGO WHEN USDA OIE ET AL MADE ATYPICAL SCRAPIE A LEGAL TRADING COMMODITY, I SAID YOUR PUTTING THE CART BEFORE THE HORSE, AND THAT'S EXACTLY WHAT THEY DID, and it's called in Texas, TEXAS TSE PRION HOLDEM POKER, WHO'S ALL IN $$$
***> AS is considered more likely (subjective probability range 50–66%) that AS is a non-contagious, rather than a contagious, disease.
***> All sheep with the ARQ/ARQ and ARQ/ARR genotypes developed Atypical/Nor98 scrapie confirmed by immunohistochemistry, and one sheep with the VRQ/ARQ genotype had detectable PrPSc consistent with Atypical/Nor98 scrapie at the experimental endpoint of 8 years.
Transmission of the atypical/Nor98 scrapie agent to Suffolk sheep with VRQ/ARQ, ARQ/ARQ, and ARQ/ARR genotypes
Eric D. Cassmann, Najiba Mammadova, S. Jo Moore, Sylvie Benestad, Justin J. Greenlee
Published: February 11, 2021
Abstract
Scrapie is a transmissible spongiform encephalopathy that occurs in sheep. Atypical/Nor98 scrapie occurs in sheep that tend to be resistant to classical scrapie and it is thought to occur spontaneously. The purpose of this study was to test the transmission of the Atypical/Nor98 scrapie agent in three genotypes of Suffolk sheep and characterize the distribution of misfolded prion protein (PrPSc). Ten sheep were intracranially inoculated with brain homogenate from a sheep with Atypical/Nor98 scrapie. All sheep with the ARQ/ARQ and ARQ/ARR genotypes developed Atypical/Nor98 scrapie confirmed by immunohistochemistry, and one sheep with the VRQ/ARQ genotype had detectable PrPSc consistent with Atypical/Nor98 scrapie at the experimental endpoint of 8 years. Sheep with mild early accumulations of PrPSc in the cerebellum had concomitant retinal PrPSc. Accordingly, large amounts of retinal PrPSc were identified in clinically affected sheep and sheep with dense accumulations of PrPSc in the cerebellum.
***> These data confirm that ARR/ARR sheep cannot be considered to be fully resistant to classical scrapie.
Journal of General Virology header logoVolume 98, Issue 8
Classical scrapie transmission in ARR/ARR genotype sheep Free
Caroline Lacroux1,†, Hervé Cassard1,†, Hugh Simmons2, Jean Yves Douet1, Fabien Corbière1, Severine Lugan1, Pierette Costes1, Naima Aron1, Alvina Huor1, Cécile Tillier1, Francois Schelcher1, Olivier Andreoletti1
Published: 01 August 2017 https://doi.org/10.1099/jgv.0.000861 ;
ABSTRACT
The ARR allele is considered to provide a very strong resistance against classical scrapie infection in sheep. In this study, we report the occurrence of clinical transmissible spongiform encephalopathy in ARR/ARR sheep, following their inoculation by the intracerebral route with a classical scrapie isolate. On first passage, the disease displayed an incomplete attack rate transmission, with incubation periods exceeding 6 years. On second passage, the obtained prion did not display better abilities to propagate than the original isolate. These transmission results contrasted with the 100 % attack rate and the short incubation periods observed in ARQ/ARQ sheep challenged with the same isolate. These data confirm that ARR/ARR sheep cannot be considered to be fully resistant to classical scrapie. However, they also support the contention that classical scrapie has a very limited capacity to transmit and adapt to ARR/ARR sheep.
''These data confirm that ARR/ARR sheep cannot be considered to be fully resistant to classical scrapie. However, they also support the contention that classical scrapie has a very limited capacity to transmit and adapt to ARR/ARR sheep.''
Emerg Infect Dis. 2007 Aug; 13(8): 1201–1207.
doi: 10.3201/eid1308.070077
PMCID: PMC2828083
PMID: 17953092
Classic Scrapie in Sheep with the ARR/ARR Prion Genotype in Germany and France
Martin H. Groschup,corresponding author* 1 Caroline Lacroux,† 1 Anne Buschmann,* Gesine Lühken,‡ Jacinthe Mathey,† Martin Eiden,* Séverine Lugan,† Christine Hoffmann,* Juan Carlos Espinosa,§ Thierry Baron,¶ Juan Maria Torres,§ Georg Erhardt,‡ and Olivier Andreoletti†
Abstract
In the past, natural scrapie and bovine spongiform encephalopathy (BSE) infections have essentially not been diagnosed in sheep homozygous for the A136R154R171 haplotype of the prion protein. This genotype was therefore assumed to confer resistance to BSE and classic scrapie under natural exposure conditions. Hence, to exclude prions from the human food chain, massive breeding efforts have been undertaken in the European Union to amplify this gene. We report the identification of 2 natural scrapie cases in ARR/ARR sheep that have biochemical and transmission characteristics similar to cases of classic scrapie, although the abnormally folded prion protein (PrPSc) was associated with a lower proteinase-K resistance. PrPSc was clearly distinct from BSE prions passaged in sheep and from atypical scrapie prions. These findings strongly support the idea that scrapie prions are a mosaic of agents, which harbor different biologic properties, rather than a unique entity.
snip...
The discovery of these 2 cases clearly indicates that the genetic resistance of ARR/ARR sheep to the so-called classic scrapie agent is not absolute. It also provides evidence that, rather than being a single entity, scrapie is a mosaic of infectious agents harboring different biologic properties in its natural host. Finally, although many thousands of cases of classic scrapie have been reported in sheep of other PrP genotypes and hundreds of thousands of rapid tests have been performed in Europe since the implementation of active TSE surveillance in small ruminants began in 2001, the discovery of these 2 ARR/ARR cases supports the idea that such infections are extremely rare.
''The discovery of these 2 cases clearly indicates that the genetic resistance of ARR/ARR sheep to the so-called classic scrapie agent is not absolute.''
Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice.
*** These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
A newly identified type of scrapie agent can naturally infect sheep with resistant PrP genotypes
Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?, Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,? +Author Affiliations
*Virologie Immunologie Moléculaires and ?Génétique Biochimique et Cytogénétique, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon, France; **Pathologie Infectieuse et Immunologie, Institut National de la Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology, National Veterinary Institute, 0033 Oslo, Norway
***Edited by Stanley B. Prusiner, University of California, San Francisco, CA (received for review March 21, 2005)
Abstract
Scrapie in small ruminants belongs to transmissible spongiform encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative disorders that affect humans and animals and can transmit within and between species by ingestion or inoculation. Conversion of the host-encoded prion protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP (PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified surveillance of scrapie in the European Union, together with the improvement of PrPSc detection techniques, has led to the discovery of a growing number of so-called atypical scrapie cases. These include clinical Nor98 cases first identified in Norwegian sheep on the basis of unusual pathological and PrPSc molecular features and "cases" that produced discordant responses in the rapid tests currently applied to the large-scale random screening of slaughtered or fallen animals. Worryingly, a substantial proportion of such cases involved sheep with PrP genotypes known until now to confer natural resistance to conventional scrapie. Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice. *** These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.
''These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.''
CWD TSE PRION AND ZOONOTIC, ZOONOSIS, POTENTIAL
Subject: Re: DEER SPONGIFORM ENCEPHALOPATHY SURVEY & HOUND STUDY
Date: Fri, 18 Oct 2002 23:12:22 +0100
From: Steve Dealler
Reply-To: Bovine Spongiform Encephalopathy Organization: Netscape Online member
To: BSE-L@ References:
Dear Terry,
An excellent piece of review as this literature is desperately difficult to get back from Government sites.
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
Steve Dealler ===============
''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...see full text;
MONDAY, FEBRUARY 25, 2019
***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
***> ''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).''
***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***
***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<***
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<***
***> 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.'' Scientific opinion on chronic wasting disease (II) <***
***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.
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases).
Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.
*** 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.
We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
==============
***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.
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 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
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.
Title: 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.
GAME FARM INDUSTRY WANTS TO COVER UP FINDINGS OF INCREASE RISK TO CJD FROM CERVID
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 regarding 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
Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasized by the finding that some strains of scrapie produce lesions identical to the once which characterize the human dementias"
Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the scrapie problem urgent if the sheep industry is not to suffer grievously.
snip...
76/10.12/4.6
IN CONFIDENCE
SCRAPIE TRANSMISSION TO CHIMPANZEES
IN CONFIDENCE
reference...
RB3.20
TRANSMISSION TO CHIMPANZEES
1. Kuru and CJD have been successfully transmitted to chimpanzees but scrapie and TME have not.
2. 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, ilp and i/v) :
3. 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.
4. 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.
5. 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.
6. 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
23 September 1990
CVO (+Mr Wells' comments)
Dr T W A Little
Dr B J Shreeve
90/9.23/1.1.
http://web.archive.org/web/20090506041740/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf
IN CONFIDENCE CHIMPANZEES
CODE 18-77 Reference RB3.46
Some further information that may assist in decision making has been gained by discussion with Dr Rosalind Ridley.
She says that careful study of Gajdusek's work shows no increased susceptibility of chimpanzees over New World Monkeys such as Squirrel Monkeys. She does not think it would tell you anything about the susceptibility to man. Also Gajdusek did not, she believes, challenge chimpanzees with scrapie as severely as we did pigs and we know little of that source of scrapie. Comparisons would be difficult. She also would not expect the Home Office to sanction such experiments here unless there was a very clear and important objective that would be important for human health protection. She doubted such a case could be made. If this is the case she thought it would be unethical to do an experiment abroad because we could not do it in our own country.
Retrospectively she feels they should have put up more marmosets than they did. They all remain healthy. They would normally regard the transmission as negative if no disease resulted in five years.
We are not being asked for a decision but I think that before we made one we should gain as much knowledge as we can. If we decided to proceed we would have to bear any criticisms for many years if there was an adverse view by scientists or media. This should not be undertaken lightly. There is already some adverse comment here, I gather, on the pig experiment though that will subside.
The Gibbs' (as' distinct from Schellekers') study is somewhat different. We are merely supplying material for comparative studies in a laboratory with the greatest experience of human SEs in the world and it has been sanctioned by USDA (though we do not know for certain yet if chimpanzees specifically will be used). This would keep it at a lower profile than if we conducted such an experiment in the UK or Europe.
I consider we must have very powerful and defendable objectives to go beyond Gibbs' proposed experiments and should not initiate others just because an offer has been made.
Scientists have a responsibility to seek other methods of investigative research other than animal experimentation. At present no objective has convinced me we need to do research using Chimpanzees - a species in need of protection. Resisting such proposals would enable us to communicate that information to the scientist and the public should the need arise. A line would have been drawn.
CVO cc Dr T Dr B W A Little Dr B J Shreeve
R Bradley
26 September 1990
90/9.26/3.2
http://web.archive.org/web/20090506041605/http://www.bseinquiry.gov.uk/files/yb/1990/09/26003001.pdf
this is tse prion political theater here, i.e. what i call TSE PRION POKER...tss
3. Prof. A. Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs.
snip...
PAGE 26
Transmission Studies
Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS
resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
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.
snip...see;
IN CONFIDENCE
PERCEPTIONS OF UNCONVENTIONAL SLOW VIRUS DISEASE OF ANIMALS IN THE USA
GAH WELLS
REPORT OF A VISIT TO THE USA
APRIL-MAY 1989
why do we not want to do TSE transmission studies on chimpanzees $
5. A positive result from a chimpanzee challenged severly 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.
snip...
price of prion poker goes up for cwd to cattle;
Monday, April 04, 2016
*** Limited amplification of chronic wasting disease prions in the peripheral tissues of intracerebrally inoculated cattle ***
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
snip...
In the USA, under the Food and Drug Administration's BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system. However, this recommendation is guidance and not a requirement by law.
Animals considered at high risk for CWD include:
1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and
2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.
Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.
The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.
Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.
There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.
snip...
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.
snip...
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).
snip...
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. 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.
snip...
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.
snip...
Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease
Nathaniel D. Denkers ,Clare E. Hoover ,Kristen A. Davenport,Davin M. Henderson,Erin E. McNulty,Amy V. Nalls,Candace K. Mathiason,Edward A. Hoover
Published: August 20, 2020
We report that oral exposure to as little as 300 nanograms (ng) of CWD-positive brain or to saliva containing seeding activity equivalent to 300 ng of CWD-positive brain, were sufficient to transmit CWD disease. This was true whether the inoculum was administered as a single bolus or divided as three weekly 100 ng exposures. However, when the 300 ng total dose was apportioned as 10, 30 ng doses delivered over 12 weeks, no infection occurred. While low-dose exposures to prions of brain or saliva origin prolonged the time from inoculation to first detection of infection, once infection was established, we observed no differences in disease pathogenesis. 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.
i am thinking of that 10,000,000 POUNDS OF BLOOD LACED MEAT AND BONE MEAL IN COMMERCE WARNING LETTER back in 2007, see;
SATURDAY, NOVEMBER 4, 2017
FDA 589.2000, Section 21 C.F.R. Animal Proteins Prohibited in Ruminant Feed WARNING Letters and FEED MILL VIOLATIONS OBSERVATIONS 2017 to 2006
FRIDAY, FEBRUARY 11, 2022
Passage of the CWD agent through meadow voles results in increased attack rates and decreased incubation periods in raccoons
TUESDAY, APRIL 26, 2022
Susceptibility of Beavers to Chronic Wasting Disease
Saturday, April 9, 2022
EFSA EU Request for a scientific opinion on the monitoring of Chronic Wasting Disease (CWD) EFSA-Q-2022-00114 M-2022-00040 Singeltary Submission
ENVIRONMENT FACTORS FOR THE TRANSMISSION OF CWD TSE PRP
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Environment International
Available online 13 June 2022, 107347
Environment International
Sensitive detection of chronic wasting disease prions recovered from environmentally relevant surfaces
Qi Yuana Gag e Rowdenb Tiffany M.Wolfc Marc D.Schwabenlanderb Peter A.LarsenbShannon L.Bartelt-Huntd Jason C.Bartza
a Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, 68178, United States of America
b Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN, 55108, United States of America
c Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, MN, 55108, United States of America
d Department of Civil and Environmental Engineering, Peter Kiewit Institute, University of Nebraska-Lincoln, Omaha, Nebraska, 68182, United States of America
Received 26 April 2022, Revised 8 June 2022, Accepted 9 June 2022, Available online 13 June 2022.
Get rights and content
Under a Creative Commons license Open access
Highlights • An innovative method for prion recovery from swabs was developed.
• Recovery of prions decreased as swab-drying time was increased.
• Recovery of CWD prions from stainless steel and glass was approximately 30%.
• RT-QuIC enhanced CWD prion detection by 4 orders of magnitude.
• Surface-recovered CWD prion was sufficient for efficient RT-QuIC detection.
Abstract
Chronic wasting disease (CWD) has been identified in 30 states in the United States, four provinces in Canada, and recently emerged in Scandinavia. The association of CWD prions with environmental materials such as soil, plants, and surfaces may enhance the persistence of CWD prion infectivity in the environment exacerbating disease transmission. Identifying and quantifying CWD prions in the environment is significant for prion monitoring and disease transmission control. A systematic method for CWD prion quantification from associated environmental materials, however, does not exist. In this study, we developed an innovative method for extracting prions from swabs and recovering CWD prions swabbed from different types of surfaces including glass, stainless steel, and wood. We found that samples dried on swabs were unfavorable for prion extraction, with the greatest prion recovery from wet swabs. Using this swabbing technique, the recovery of CWD prions dried to glass or stainless steel was approximately 30% in most cases, whereas that from wood was undetectable by conventional prion immunodetection techniques. Real-time quake-induced conversion (RT-QuIC) analysis of these same samples resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this method was similar to the original CWD prion load applied to the surface. This combined surface swabbing and RT-QuIC detection method provides an ultrasensitive means for prion detection across many settings and applications.
snip...
5. Conclusions
Chronic wasting disease is spreading in North America and it is hypothesized that in CWD-endemic areas environmental persistence of CWD prions can exacerbate disease transmission. The development of a sensitive CWD prion detection method from environmentally relevant surfaces is significant for monitoring, risk assessment, and control of CWD. In this study, we developed a novel swab-extraction procedure for field deployable sampling of CWD prions from stainless steel, glass, and wood. We found that extended swab-drying was unfavorable for extraction, indicating that hydrated storage of swabs after sampling aided in prion recovery. Recoverable CWD prions from stainless steel and glass was approximately 30%, which was greater than from wood. RT-QuIC analysis of the swab extracts resulted in an increase of the detection limit of CWD prions from stainless steel by 4 orders of magnitude compared to conventional immunodetection techniques. More importantly, the RT-QuIC detection of CWD prions recovered from stainless steel surfaces using this developed method was similar to the original CWD prion load without surface contact. This method of prion sampling and recovery, in combination with ultrasensitive detection methods, allows for prion detection from contaminated environmental surfaces.
Research Paper
Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer
Anthony Ness, Aradhana Jacob, Kelsey Saboraki, Alicia Otero, Danielle Gushue, Diana Martinez Moreno, Melanie de Peña, Xinli Tang, Judd Aiken, Susan Lingle & Debbie McKenzie ORCID Icon show less
Pages 40-57 | Received 03 Feb 2022, Accepted 13 May 2022, Published online: 29 May 2022
Download citation
ABSTRACT
Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.
KEYWORDS: Prion chronic wasting diseasesex differences species differences disease prevalence cervid protein expression glands
Paper
Rapid recontamination of a farm building occurs after attempted prion removal
Kevin Christopher Gough BSc (Hons), PhD Claire Alison Baker BSc (Hons) Steve Hawkins MIBiol Hugh Simmons BVSc, MRCVS, MBA, MA Timm Konold DrMedVet, PhD, MRCVS … See all authors
First published: 19 January 2019 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 scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.
***>This is very likely to have parallels with control efforts for CWD in cervids.
***> Infectious agent of sheep scrapie may persist in the environment for at least 16 years
***> Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded.
JOURNAL OF GENERAL VIROLOGY Volume 87, Issue 12
Infectious agent of sheep scrapie may persist in the environment for at least 16 years Free
Gudmundur Georgsson1, Sigurdur Sigurdarson2, Paul Brown3
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
imageTimm Konold1*, imageStephen A. C. Hawkins2, imageLisa C. Thurston3, imageBen C. Maddison4, imageKevin C. Gough5, imageAnthony Duarte1 and imageHugh A. Simmons1
The findings of this study highlight the role of field furniture used by scrapie-infected sheep to act as a reservoir for disease re-introduction although infectivity declines considerably if the field furniture has not been in contact with scrapie-infected sheep for several months. PMCA may not be as sensitive as VRQ/VRQ sheep to test for environmental contamination.
snip...
Discussion
snip...
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.
***> 172. Establishment of PrPCWD extraction and detection methods in the farm soil
Kyung Je Park, Hoo Chang Park, In Soon Roh, Hyo Jin Kim, Hae-Eun Kang and Hyun Joo Sohn
Foreign Animal Disease Division, Animal and Plant Quarantine Agency, Gimcheon, Gyeongsangbuk-do, Korea
Conclusions: Our studies showed that PrPCWD persist in 0.001% CWD contaminated soil for at least 4 year and natural CWD-affected farm soil. When cervid reintroduced into CWD outbreak farm, the strict decontamination procedures of the infectious agent should be performed in the environment of CWD-affected cervid habitat.
Published: 06 September 2021
***> Chronic wasting disease: a cervid prion infection looming to spillover
Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie
Veterinary Research volume 52, Article number: 115 (2021)
THE tse prion aka mad cow type disease is not your normal pathogen.
The TSE prion disease survives ashing to 600 degrees celsius, that’s around 1112 degrees farenheit.
you cannot cook the TSE prion disease out of meat.
you can take the ash and mix it with saline and inject that ash into a mouse, and the mouse will go down with TSE.
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production as well.
the TSE prion agent also survives Simulated Wastewater Treatment Processes.
IN fact, you should also know that the TSE Prion agent will survive in the environment for years, if not decades.
you can bury it and it will not go away.
The TSE agent is capable of infected your water table i.e. Detection of protease-resistant cervid prion protein in water from a CWD-endemic area.
it’s not your ordinary pathogen you can just cook it out and be done with.
***> that’s what’s so worrisome about Iatrogenic mode of transmission, a simple autoclave will not kill this TSE prion agent.
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
MONDAY, APRIL 19, 2021
Evaluation of the application for new alternative biodiesel production process for rendered fat including Category 1 animal by-products (BDI-RepCat® process, AT) ???
Detection of protease-resistant cervid prion protein in water from a CWD-endemic area
A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing
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
THURSDAY, FEBRUARY 28, 2019
BSE infectivity survives burial for five years with only limited spread
5 or 6 years quarantine is NOT LONG ENOUGH FOR CWD TSE PRION !!!
QUARANTINE NEEDS TO BE 21 YEARS FOR CWD TSE PRION !
FRIDAY, APRIL 30, 2021
Should Property Evaluations Contain Scrapie, CWD, TSE PRION Environmental Contamination of the land?
***> Confidential!!!!
***> As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
and so it seems...
Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years
Published: May 9, 2007
snip...
Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field.
snip...
Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document
SATURDAY, SEPTEMBER 24, 2022
Transmission of CH1641 in cattle
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification
Sunday, January 10, 2021
APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087] Singeltary Submission June 17, 2019
APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087] Singeltary Submission
Greetings APHIS et al,
I would kindly like to comment on APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087], and my comments are as follows, with the latest peer review and transmission studies as references of evidence.
THE OIE/USDA BSE Minimal Risk Region MRR is nothing more than free pass to import and export the Transmissible Spongiform Encephalopathy TSE Prion disease. December 2003, when the USDA et al lost it's supposedly 'GOLD CARD' ie BSE FREE STATUS (that was based on nothing more than not looking and not finding BSE), once the USA lost it's gold card BSE Free status, the USDA OIE et al worked hard and fast to change the BSE Geographical Risk Statuses i.e. the BSE GBR's, and replaced it with the BSE MRR policy, the legal tool to trade mad cow type disease TSE Prion Globally. The USA is doing just what the UK did, when they shipped mad cow disease around the world, except with the BSE MRR policy, it's now legal.
Also, the whole concept of the BSE MRR policy is based on a false pretense, that atypical BSE is not transmissible, and that only typical c-BSE is transmissible via feed. This notion that atypical BSE TSE Prion is an old age cow disease that is not infectious is absolutely false, there is NO science to show this, and on the contrary, we now know that atypical BSE will transmit by ORAL ROUTES, but even much more concerning now, recent science has shown that Chronic Wasting Disease CWD TSE Prion in deer and elk which is rampant with no stopping is sight in the USA, and Scrapie TSE Prion in sheep and goat, will transmit to PIGS by oral routes, this is our worst nightmare, showing even more risk factors for the USA FDA PART 589 TSE PRION FEED ban.
The FDA PART 589 TSE PRION FEED ban has failed terribly bad, and is still failing, since August 1997. there is tonnage and tonnage of banned potential mad cow feed that went into commerce, and still is, with one decade, 10 YEARS, post August 1997 FDA PART 589 TSE PRION FEED ban, 2007, with 10,000,000 POUNDS, with REASON, Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement. you can see all these feed ban warning letters and tonnage of mad cow feed in commerce, year after year, that is not accessible on the internet anymore like it use to be, you can see history of the FDA failure August 1997 FDA PART 589 TSE PRION FEED ban here, but remember this, we have a new outbreak of TSE Prion disease in a new livestock species, the camel, and this too is very worrisome.
WITH the OIE and the USDA et al weakening the global TSE prion surveillance, by not classifying the atypical Scrapie as TSE Prion disease, and the notion that they want to do the same thing with typical scrapie and atypical BSE, it's just not scientific.
WE MUST abolish the BSE MRR policy, go back to the BSE GBR risk assessments by country, and enhance them to include all strains of TSE Prion disease in all species. With Chronic Wasting CWD TSE Prion disease spreading in Europe, now including, Norway, Finland, Sweden, also in Korea, Canada and the USA, and the TSE Prion in Camels, the fact the the USA is feeding potentially CWD, Scrapie, BSE, typical and atypical, to other animals, and shipping both this feed and or live animals or even grains around the globe, potentially exposed or infected with the TSE Prion. this APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087], under it's present definition, does NOT show the true risk of the TSE Prion in any country. as i said, it's nothing more than a legal tool to trade the TSE Prion around the globe, nothing but ink on paper.
AS long as the BSE MRR policy stays in effect, TSE Prion disease will continued to be bought and sold as food for both humans and animals around the globe, and the future ramifications from friendly fire there from, i.e. iatrogenic exposure and transmission there from from all of the above, should not be underestimated. ...
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO
On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
snip...see full text;
SUNDAY, OCTOBER 16, 2022
USDA Transmissible Spongiform Encephalopathy TSE Prion Action Plan National Program 103 Animal Health 2022-2027
FRIDAY, SEPTEMBER 23, 2022
SPILLOVER CWD TSE PRION INTO DIFFERENT SPECIES, pigs, sheep, cattle, camel, and humans, what if?
TUESDAY, OCTOBER 18, 2022
Assessing the Potential Transmissibility of Bovine and Cervid Prions with a Human Prion Protein-based Model ARS RESEARCH
SATURDAY, SEPTEMBER 24, 2022
TEXAS CWD TSE PRION TOTAL TO DATE CONFIRMED AT 392 captive or free-ranging cervids — including white-tailed deer, mule deer, red deer and elk — in 16 Texas counties have tested positive for CWD.
Texas Chronic Wasting Disease Confirmed at a Limestone County Deer Breeding Facility
SATURDAY, SEPTEMBER 24, 2022
Transmission of CH1641 in cattle
Control of Chronic Wasting Disease OMB Control Number: 0579-0189 APHIS-2021-0004 Singeltary Submission
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification
Sunday, January 10, 2021
APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087] Singeltary Submission June 17, 2019
APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087] Singeltary Submission
Greetings APHIS et al,
I would kindly like to comment on APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087], and my comments are as follows, with the latest peer review and transmission studies as references of evidence.
THE OIE/USDA BSE Minimal Risk Region MRR is nothing more than free pass to import and export the Transmissible Spongiform Encephalopathy TSE Prion disease. December 2003, when the USDA et al lost it's supposedly 'GOLD CARD' ie BSE FREE STATUS (that was based on nothing more than not looking and not finding BSE), once the USA lost it's gold card BSE Free status, the USDA OIE et al worked hard and fast to change the BSE Geographical Risk Statuses i.e. the BSE GBR's, and replaced it with the BSE MRR policy, the legal tool to trade mad cow type disease TSE Prion Globally. The USA is doing just what the UK did, when they shipped mad cow disease around the world, except with the BSE MRR policy, it's now legal.
Also, the whole concept of the BSE MRR policy is based on a false pretense, that atypical BSE is not transmissible, and that only typical c-BSE is transmissible via feed. This notion that atypical BSE TSE Prion is an old age cow disease that is not infectious is absolutely false, there is NO science to show this, and on the contrary, we now know that atypical BSE will transmit by ORAL ROUTES, but even much more concerning now, recent science has shown that Chronic Wasting Disease CWD TSE Prion in deer and elk which is rampant with no stopping is sight in the USA, and Scrapie TSE Prion in sheep and goat, will transmit to PIGS by oral routes, this is our worst nightmare, showing even more risk factors for the USA FDA PART 589 TSE PRION FEED ban.
The FDA PART 589 TSE PRION FEED ban has failed terribly bad, and is still failing, since August 1997. there is tonnage and tonnage of banned potential mad cow feed that went into commerce, and still is, with one decade, 10 YEARS, post August 1997 FDA PART 589 TSE PRION FEED ban, 2007, with 10,000,000 POUNDS, with REASON, Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement. you can see all these feed ban warning letters and tonnage of mad cow feed in commerce, year after year, that is not accessible on the internet anymore like it use to be, you can see history of the FDA failure August 1997 FDA PART 589 TSE PRION FEED ban here, but remember this, we have a new outbreak of TSE Prion disease in a new livestock species, the camel, and this too is very worrisome.
WITH the OIE and the USDA et al weakening the global TSE prion surveillance, by not classifying the atypical Scrapie as TSE Prion disease, and the notion that they want to do the same thing with typical scrapie and atypical BSE, it's just not scientific.
WE MUST abolish the BSE MRR policy, go back to the BSE GBR risk assessments by country, and enhance them to include all strains of TSE Prion disease in all species. With Chronic Wasting CWD TSE Prion disease spreading in Europe, now including, Norway, Finland, Sweden, also in Korea, Canada and the USA, and the TSE Prion in Camels, the fact the the USA is feeding potentially CWD, Scrapie, BSE, typical and atypical, to other animals, and shipping both this feed and or live animals or even grains around the globe, potentially exposed or infected with the TSE Prion. this APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087], under it's present definition, does NOT show the true risk of the TSE Prion in any country. as i said, it's nothing more than a legal tool to trade the TSE Prion around the globe, nothing but ink on paper.
AS long as the BSE MRR policy stays in effect, TSE Prion disease will continued to be bought and sold as food for both humans and animals around the globe, and the future ramifications from friendly fire there from, i.e. iatrogenic exposure and transmission there from from all of the above, should not be underestimated. ...
PRION 2022 ABSTRACTS, AND A BIG THANK YOU TO
On behalf of the Prion2020/2022 Congress Organizing Committee and the NeuroPrion Association, we heartily invite you to join us for the International Conference Prion2020/2022 from 13.-16. September 2022 in Göttingen.
Prion 2022 Conference abstracts: pushing the boundaries
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
2:54 PM
0 Comments
