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Wednesday, April 27, 2022

Missouri MDC reports final CWD results for 2021 deer season with 86 testing positive for CWD

Missouri MDC reports final CWD results for 2021 deer season with 86 testing positive for CWD

MDC reports final CWD results for 2021 deer season 

MDC thanks hunters, landowners, taxidermists, and meat processors who participated in CWD sampling and management activities.

JEFFERSON CITY, Mo. – The Missouri Department of Conservation (MDC) reports that it sampled and tested more than 32,000 deer for chronic wasting disease (CWD) between July 2021 and April 2022. Of the more than 32,000 deer sampled, 86 tested positive for CWD.

Those deer bring the total number of CWD cases found in the state to 292 since the first case in wild deer was found by MDC in early 2012. Including recent sampling efforts, MDC has collected more than 210,000 tissue samples for CWD testing since the disease was first detected.

Of deer tested this past season, MDC found CWD-positive deer in 18 counties: Adair (2), Barry (4), Cedar (2), Christian (2), Franklin (6), Howell (1), Jefferson (12), Linn (12), Macon (10), Oregon (6), Perry (2), Pulaski (1), Putnam (1), St. Clair (1), Ste. Genevieve (15), Stone (6), Taney (2), and Washington (1).

CWD-positive cases in Barry, Christian, Howell, and Washington counties marked the first detections of the disease in these counties.

More than 18,700 of the 32,000-plus deer tested were sampled as part of MDC mandatory CWD sampling efforts during the opening weekend of the November portion of the firearms deer season, Nov. 13 and 14. Mandatory sampling required hunters who harvested deer in any of the 34 MDC CWD Management Zone counties during that weekend to present their deer for CWD sampling.

Of the more than 32,000 deer sampled, about 3,000 were collected through MDC’s partnerships with many landowners in localized areas where CWD has been found. MDC works with local landowners on a voluntary basis to remove deer through targeted culling after the close of regular deer seasons in immediate areas where CWD has been recently found.

“These landowners are critical in slowing the spread of CWD by removing additional infected deer from the landscape and reducing deer numbers in targeted areas,” said MDC Wildlife Health Program Supervisor Jasmine Batten. “Participation by landowners is entirely voluntary, and all meat from deer that do not test positive for CWD is either returned to the landowner or donated to Share the Harvest.”

Batten also thanked the hunters, taxidermists, and meat processors who helped with CWD sampling.

“We are very grateful to the thousands of deer hunters who brought in their deer for CWD sampling, along with the 109 taxidermists and 34 meat processors across the state who collected and submitted more than 9,000 CWD samples,” Batten said. “These important partners provide critical surveillance data, give hunters additional opportunities to have their deer tested, and ensure that meat from deer harvested in CWD Management Zone counties is tested before venison donations are sent to food pantries.”

CWD is a deadly illness in white-tailed deer and other members of the deer family, called cervids. CWD sampling involves cutting an incision across the throat of harvested deer to remove lymph nodes for testing. Tissue samples are sent to an independent lab for testing. CWD has been found in Missouri and is slowly spreading. MDC is working with conservation partners to find cases of CWD and limit its spread. CWD remains relatively rare in the state at this time. Learn more about CWD from the MDC website at mdc.mo.gov/cwd.


Chronic Wasting Disease Regulations

The CWD Management Zone includes counties within approximately 10 miles of CWD detections. Special regulations apply in these counties.
For the 2021–2022 deer seasons, the CWD Management Zone includes Adair, Barry, Camden, Cedar, Chariton, Christian, Clark, Crawford, Franklin, Gasconade, Hickory, Howell, Jefferson, Knox, Laclede, Linn, Macon, McDonald, Mercer, Oregon, Ozark, Perry, Polk, Pulaski, Putnam, St. Charles, St. Clair, St. Francois, Ste. Genevieve, Stone, Sullivan, Taney, Warren, and Washington counties.

Fall 2021 Mandatory CWD Sampling

If you harvest a deer from counties in the CWD Management Zone during Nov. 13 or 14, 2021, you must take your deer — or just the head — on the day of harvest to a CWD sampling station. Hunters are reminded to follow new carcass transport regulations when traveling to CWD sampling stations.

Special Regulations for the CWD Management Zone


see also;


Missouri CWD TSE PrP 28 confirmed positive test results so far for the current sampling season (July 1, 2021 - June 30, 2022) 

2021-2022 Sampling Results to Date

The table below shows MDC sampling efforts and test results so far for the current sampling season (July 1, 2021 - June 30, 2022). These numbers are subject to frequent change.

CWD Sampling Results

Area Positives Negatives Pending Total

Inside CWD Management Zone 28 20995 676 21699

Statewide (Outside of Zone) 0 2844 652 3496

TOTAL 28 23839 1328 25195

CWD Positives by County

County Positives

Barry 3

Christian 1

Franklin 1

Jefferson 3

Linn 6

Macon 4

Putnam 1

Ste Genevieve 4

Stone 5

CWD Cases Found in Free-Ranging Deer Through June 30, 2021

This table shows the total number of CWD cases found in Missouri free-ranging deer by county through June 30, 2020. Positives for the current surveillance season are not included in this table.

Total CWD-positives (free-ranging deer) by County (through 6/30/2021)

County Total Positives Year of 1st Detection

Total 206 

Macon 47 2011-12

Adair 21 2014-15

Cole 1 2014-15

Franklin 24 2015-16

Linn 25 2015-16

Jefferson 9 2016-17

St Clair 9 2016-17

Cedar 1 2017-18

Perry 3 2017-18

Polk 8 2017-18

Ste Genevieve 35 2017-18

Crawford 1 2018-19

Mercer 1 2018-19

Oregon 10 2018-19

Stone 4 2018-19

Taney 4 2018-19

Pulaski 1 2020-2021

Putnam 2 2020-2021



map


MONDAY, APRIL 26, 2021

Missouri MDC REPORTS FINAL CWD RESULTS FOR 2020-2021 44 POSITIVE WITH TOTAL TO DATE 206 CONFIRMED


Missouri 2019 - 2020 CWD



Captive Deer and Elk in Missouri

Captive Cervids: Elk, elk-hybrids, red deer, roe deer, sika deer, white-tailed deer, mule deer, moose, and related species in the Cervidae family, raised under confinement or agricultural conditions for the production of meat or other agricultural products or for sport or exhibition, and free-ranging cervidae when they are captured for any purpose.


For information concerning health requirements governing the admission of CWD status herds of Elk, elk-hybrids, red deer, roe deer, sika deer, white-tailed deer, mule deer, moose, and related species in the Cervidae family, sold, traded, exchanged, leased, donated, relinquished or otherwise involved in a change of ownership contact the Division of Animal Health at (573) 751-3377, or e-mail Animal.Health@mda.mo.gov.

Dept. of Ag Notified of Two Positive Tests for CWD at Macon County Facility

March 07, 2012

Dept. of Ag Notified of Two Positive Tests for CWD at Macon County Facility The Missouri Department of Agriculture has received two additional positive test results for Chronic Wasting Disease (CWD) in white-tailed deer harvested at a captive wildlife facility in Macon County. Depopulation is continuing at the facility, operated by Heartland Wildlife Ranches, LLC, with approximately 320 animals harvested and tested since the facility's first positive result was found in October 2011.

MDA has received negative test results for approximately 280 animals, with results pending from the National Veterinary Services Laboratory for the roughly 40 remaining samples. The current harvest and testing protocol requires the facility to remain under its current quarantine until all animals have been harvested and tested for CWD, which is a neurological disease found in deer, elk and moose. There is no evidence CWD can be transmitted to humans or non-cervid animals, such as livestock and household pets.

For more information on CWD visit the Department online at http://www.mda.mo.gov.


Depopulation Efforts Conclude at Macon County Facility May 07, 2012

Depopulation Efforts Conclude at Macon County Facility Depopulation efforts have concluded at a captive wildlife facility in Macon County, and testing for Chronic Wasting Disease (CWD) has been completed on all animals harvested. The roughly 3,000-acre facility operated by Heartland Wildlife Ranches LLC remains quarantined. The Missouri departments of Agriculture, Conservation and Health and Senior Services will continue to work with Heartland Wildlife Ranches LLC, to develop a five year management plan for the Macon County facility.

In total, 10 cervids tested positive and 356 cervids tested negative within the Macon County premises. None of the positive samples were obtained from the existing breeding herd. State and federal staff will be conducting a final verification over the next several weeks to ensure the facility has been fully depopulated.

Heartland Wildlife Ranches LLC began voluntarily depopulating their herd after the facility's first positive test for CWD was reported in October 2011 through random surveillance. Additional positive results were found in December 2011 and March 2012. Testing was completed at USDA-approved facilities and confirmed by the National Veterinary Services Laboratory in Ames, Iowa.

CWD is a neurological disease found in deer, elk and moose. There is no evidence CWD can be transmitted to humans or non-cervid animals, such as livestock and household pets.

For more information on CWD visit the Department online at http://www.mda.mo.gov.


Chronic Wasting Disease Found in Captive Deer

February 25, 2010

Chronic Wasting Disease Found in Captive Deer

The Missouri Departments of Agriculture, Conservation and Health and Senior Services and the U.S. Department of Agriculture announced today that a captive white-tailed deer in Linn County, Missouri has tested positive for Chronic Wasting Disease (CWD). CWD is a neurological disease found in deer, elk and moose.

"There is no evidence that CWD poses a risk to domestic animals or humans," said State Veterinarian Dr. Taylor Woods. "We have protocols in place to quickly and effectively handle these situations."

The animal that tested positive for CWD was a white-tailed deer inspected as part of the State's CWD surveillance and testing program. Preliminary tests were conducted by the USDA National Veterinary Services Laboratory in Ames, Iowa.

Upon receiving the confirmed CWD positive, Missouri's departments of Agriculture, Conservation and Health and Senior Services initiated their CWD Contingency Plan. The plan was developed in 2002 by the Cervid Health Committee, a task force comprised of veterinarians, animal health officers and conservation officers from USDA, MDA, MDC and DHSS working together to mitigate challenges associated with CWD.

CWD is transmitted by live animal to animal contact or soil to animal contact. The disease was first recognized in 1967 in captive mule deer in the Colorado Division of Wildlife captive wildlife research facility in Fort Collins, Colorado. CWD has been documented in deer and/or elk in Colorado, Illinois, Kansas, Michigan, Minnesota, Montana, Nebraska, New Mexico, New York, Oklahoma, South Dakota, Utah, Virginia, West Virginia, Wisconsin, and the Canadian Provinces of Alberta and Saskatchewan. There has been no evidence that the disease can be transmitted to humans.

"Missouri's proactive steps to put a testing protocol in place and create a contingency plan years ago is proving beneficial. We are in a solid position to follow pre-established steps to ensure Missouri's valuable whitetail deer resource remains healthy and strong," said Jason Sumners Missouri's Deer Biologist.

For more information regarding CWD, please contact Dr. Taylor Woods at (573) 751-3377.


CWD Test Results Negative in White-Tailed Deer on Property in Linn County March 19, 2010

CWD Test Results Negative in White-Tailed Deer on Property in Linn County Today the Missouri Departments of Agriculture and Conservation announced that tests of 50 captive deer sampled in Linn County showed no signs of Chronic Wasting Disease (CWD). Tests were conducted by the USDA National Veterinary Services Laboratory in Ames, Iowa. The Department of Conservation continues to test a sampling of free-ranging deer within a five-mile radius of the 800-acre tract where the initial CWD-positive white-tailed deer was located.

"The Missouri Department of Agriculture, Missouri Department of Conservation, Missouri Department of Health & Senior Services and USDA have worked cooperatively in putting an aggressive and effective plan in place and quickly executing that plan," said State Veterinarian Dr. Taylor Woods. "The sampling and negative test results should reassure the public that the infection does not appear widespread."

State agencies continue an active and robust tracking plan through which deer near the site are monitored for the disease.

"We will continue to monitor free-ranging deer in the surrounding area," said Bob Ziehmer, director of the Missouri Department of Conservation. "The continued cooperation of nearby landowners and support from the sportsmen in the area has been greatly appreciated."

CWD is transmitted by live animal-to-animal contact or soil-to-animal contact and has never been reported in humans or cattle. The disease was first recognized in 1967 in a captive mule deer in the Colorado Division of Wildlife research facility in Fort Collins, Colo.

For more information regarding CWD, contact the Missouri Department of Agriculture's Animal Health Division at (573) 751-3377.


Chronic Wasting Disease Found in Captive Deer

October 20, 2011

Chronic Wasting Disease Found in Captive Deer

The Missouri departments of Agriculture, Conservation and Health and Senior Services and the U.S. Department of Agriculture announced that a captive white-tailed deer in Macon County, Missouri has tested positive for Chronic Wasting Disease (CWD). CWD is a neurological disease found in deer, elk and moose.

"We have a plan in place and our team is actively working to ensure that this situation is addressed quickly and effectively," said State Veterinarian Dr. Linda Hickam. "Fortunately there is no evidence that CWD poses a risk to humans, non cervid livestock, household pets or food safety."

The animal that tested positive for CWD was a captive white-tailed deer inspected as part of the State's CWD surveillance and testing program. Preliminary tests were conducted by the USDA National Veterinary Services Laboratory in Ames, Iowa.

Upon receiving the confirmed CWD positive, Missouri's departments of Agriculture, Conservation and Health and Senior Services initiated their CWD Contingency Plan. The plan was developed in 2002 by the Cervid Health Committee, a task force comprised of veterinarians, animal health officers and conservation officers from USDA, MDA, MDC and DHSS working together to mitigate challenges associated with CWD.

In February 2010 a case of CWD was confirmed in Linn County on a captive hunting preserve operated by the same entity, Heartland Wildlife Ranches, LLC. The Linn County facility was depopulated and no further infection was identified at that facility. The current case was identified through increased surveillance required by the management plan implemented from the previous CWD incident.

CWD is transmitted by live animal to animal contact or soil to animal contact. The disease was first recognized in 1967 in captive mule deer in the Colorado Division of Wildlife captive wildlife research facility in Fort Collins, Colorado. CWD has been documented in deer and/or elk in Colorado, Illinois, Kansas, Maryland, Michigan, Minnesota, Montana, Nebraska, New Mexico, New York, North Dakota, Oklahoma, South Dakota, Utah, Virginia, West Virginia, Wisconsin, and the Canadian Provinces of Alberta and Saskatchewan. There has been no evidence that the disease can be transmitted to humans.

"Missouri's proactive steps to put a testing protocol in place and create a contingency plan years ago is proving beneficial. We are in a solid position to follow pre-established steps to ensure Missouri's valuable whitetail deer resource remains healthy and strong," said Jason Sumners Missouri's Deer Biologist, Missouri Department of Conservation.

For more information regarding CWD, please contact Missouri's State Veterinarian Dr. Linda Hickam at (573) 751-3377.


Depopulation Plan Being Developed for Captive Deer Facility in Macon County December 30, 2011

Depopulation Plan Being Developed for Captive Deer Facility in Macon County The Missouri Department of Agriculture is finalizing a depopulation and management plan for an approximately 3,000 acre captive wildlife hunting facility in northern Missouri following two positive tests for Chronic Wasting Disease. The facility, operated by Heartland Wildlife Ranches, LLC, is home to white-tail deer, elk and red deer.

The plan includes a requirement to depopulate and test all remaining animals for CWD, as well as restrictions on the future movement of animals into the facility. The plan follows multiple positive CWD tests indentified through random surveillance and extends the facility's current quarantine until all animals have been depopulated and tested for the disease.

In October, MDA received results from the USDA National Veterinary Services Laboratory in Ames, Iowa indicating that a captive white-tail deer harvested in the Macon County facility tested positive for CWD. The animal that tested positive was inspected as part of the State's CWD surveillance and testing program. A second positive test result on a captive white-tail deer within the same facility was verified late this week.

"This plan is an important step forward as we continue working to ensure that this situation is addressed quickly and effectively and that the health of Missouri's cervids is protected from this disease," said State Veterinarian Dr. Linda Hickam.

The State's CWD Contingency Plan was developed in 2002 and revised in 2003 by the Cervid Health Committee, a task force comprised of industry representatives, veterinarians and staff from the departments of Agriculture, Conservation and Health and Senior Services and the U.S. Department of Agriculture.

In February 2010 a case of CWD was confirmed in Linn County on a captive hunting preserve operated by the same entity, Heartland Wildlife Ranches, LLC. The Linn County facility was depopulated and no further infection was identified at that facility.

CWD is transmitted by live animal to animal contact or soil to animal contact. The disease was first recognized in 1967 in captive mule deer in the Colorado Division of Wildlife captive wildlife research facility in Fort Collins, Colorado. CWD has been documented in deer and/or elk in Colorado, Illinois, Kansas, Maryland, Michigan, Minnesota, Montana, Nebraska, New Mexico, New York, North Dakota, Oklahoma, South Dakota, Utah, Virginia, West Virginia, Wisconsin, and the Canadian Provinces of Alberta and Saskatchewan. There has been no evidence that the disease can be transmitted to humans.

CWD is a neurological disease found in deer, elk and moose; it has not been reported in humans or non-cervid animals.

For more information on CWD, visit the Department online at http://www.mda.mo.gov.



WEDNESDAY, DECEMBER 15, 2021 

Missouri CWD TSE PrP 28 confirmed positive test results so far for the current sampling season (July 1, 2021 - June 30, 2022)


WEDNESDAY, MAY 06, 2020 

Missouri 46 new cases Chronic Wasting Disease found, total to date at 162 documented CWD


TUESDAY, FEBRUARY 11, 2020 

Missouri MDC 2019-2020 SAMPLING RESULTS CWD TSE PRION TO DATE 28 Positive


SUNDAY, JANUARY 19, 2020 

Missouri CWD TSE Prion 2019-2020 SAMPLING RESULTS TO DATE 25 Positive


THURSDAY, JANUARY 02, 2020 

Missouri MDC officially reports more than 20 new cases of Chronic Wasting Disease CWD TSE Prion


TUESDAY, DECEMBER 31, 2019 

Missouri MDC TESTS SHOW SEVEN NEW CHRONIC WASTING DISEASE CASES IN SOUTHEAST


FRIDAY, DECEMBER 20, 2019 

Missouri MDC Confirms 24 New Cases of Chronic Wasting Disease CWD TSE Prion

THURSDAY, JUNE 06, 2019 
Missouri MDC proposes new efforts to limit spread of CWD TSE Prion To Date 116 Cases Confirmed

THURSDAY, APRIL 25, 2019 

Missouri MDC reports 41 new positive test results for CWD have been confirmed following its sampling


Saturday, September 05, 2015 

Missouri Captive Cervid Industry, CWD TSE Prion, and Procrastinating for Money, while mad deer and elk disease silently spreads 



Tuesday, June 16, 2015
 
Missouri MDC changes deer hunting regs to help slow CWD
 
 
Wednesday, March 11, 2015
 
MDC reports 11 new cases of Chronic Wasting Disease CWD in Missouri deer
 
 
Monday, January 26, 2015
 
Missouri MDC reports two new cases of CWD found in Adair and Macon counties
 
 
Tuesday, December 09, 2014
 
Missouri MDC reports one new case of CWD, found in Adair County
 
 
Friday, October 17, 2014
 
Missouri Final action on Orders of Rule making Breeders and Big Game Hunting Preserves
 
 
Thursday, September 11, 2014
 
Missouri Nixon's Veto Stands Overide Fails on Agriculture Legislation
 
How they voted: attempt to override veto of ag bill fails in the House
 
 
Thursday, May 01, 2014
 
Missouri DNR CWD prevention and captive cervid farming Update
 
 
Tuesday, March 26, 2013
 
CWD Missouri remains confined to Linn-Macon-County Core Area with four new cases
 
Wednesday, January 23, 2013
 
Missouri sixth case CWD documented northwest Macon County
 
 
Tuesday, January 24, 2012
 
CWD found in two free-ranging deer from Macon County Missouri
 
 
Friday, February 26, 2010
 
Chronic wasting disease found in Missouri deer
 
 
Sunday, March 25, 2012
 
Three more cases of CWD found in free-ranging deer in Macon County
 
 
From: Terry S. Singeltary Sr.
 
Sent: Thursday, March 29, 2012 6:26 PM
 
 
 
Subject: re-Missouri officials seek states' advice on chronic wasting disease in deer
 
 
Thursday, May 31, 2012
 
Missouri MDC staff will provide information on five recently found cases of CWD in free-ranging deer in northwest Macon County June 2, 2012
 
 
Wednesday, September 05, 2012
 
Missouri MDC seeks hunters’ help when processing harvested deer and preventing CWD
 

Thursday, December 20, 2012
 
MISSOURI Initial CWD sampling test results available online from MDC so far one adult buck has tested positive for the disease
 
 
Friday, October 21, 2011
 
Chronic Wasting Disease Found in Captive Deer Missouri
 
 
The Missouri Department of Agriculture discovers the state's first case of CWD in a captive white-tailed deer.
 
 
Friday, February 26, 2010
 
Chronic wasting disease found in Missouri deer February 25, 2010
 
Chronic Wasting Disease Found in Captive Deer
 
The Missouri Departments of Agriculture, Conservation and Health and Senior Services and the U.S. Department of Agriculture announced today that a captive white-tailed deer in Linn County, Missouri has tested positive for Chronic Wasting Disease (CWD). CWD is a neurological disease found in deer, elk and moose.
 
"There is no evidence that CWD poses a risk to domestic animals or humans," said State Veterinarian Dr. Taylor Woods. "We have protocols in place to quickly and effectively handle these situations."
 
The animal that tested positive for CWD was a white-tailed deer inspected as part of the State's CWD surveillance and testing program. Preliminary tests were conducted by the USDA National Veterinary Services Laboratory in Ames, Iowa.
 
Upon receiving the confirmed CWD positive, Missouri's departments of Agriculture, Conservation and Health and Senior Services initiated their CWD Contingency Plan. The plan was developed in 2002 by the Cervid Health Committee, a task force comprised of veterinarians, animal health officers and conservation officers from USDA, MDA, MDC and DHSS working together to mitigate challenges associated with CWD.
 
CWD is transmitted by live animal to animal contact or soil to animal contact. The disease was first recognized in 1967 in captive mule deer in the Colorado Division of Wildlife captive wildlife research facility in Fort Collins, Colorado. CWD has been documented in deer and/or elk in Colorado, Illinois, Kansas, Michigan, Minnesota, Montana, Nebraska, New Mexico, New York, Oklahoma, South Dakota, Utah, Virginia, West Virginia, Wisconsin, and the Canadian Provinces of Alberta and Saskatchewan. There has been no evidence that the disease can be transmitted to humans.
 
"Missouri's proactive steps to put a testing protocol in place and create a contingency plan years ago is proving beneficial. We are in a solid position to follow pre-established steps to ensure Missouri's valuable whitetail deer resource remains healthy and strong," said Jason Sumners Missouri's Deer Biologist.
 
For more information regarding CWD, please contact Dr. Taylor Woods at (573) 751-3377.
 
 
 
Friday, September 20, 2013
 
*** Missouri State records show gaps in oversight of captive deer farms, ranches ***
 

Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
 
Samia Hannaoui, Irina Zemlyankina, Sheng Chun Chang, Maria Immaculata Arifin, Vincent Beringue, Debbie McKEnzie, Hermann M Schatzl, Sabine Gilch
 
Affiliations:
 
1 Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary
Medicine; Hotchkiss Brain Institute; University of Calgary, Calgary, Canada
 
2 Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
 
3 Department of Biological Sciences, Center for Prions and Protein Folding Diseases, University
of Alberta, Edmonton, Canada
 
*Corresponding author. Email: sgilch@ucalgary.ca
 
 
This article is a preprint and has not been certified by peer review [what does this mean?].
 
Abstract
 
Prions cause infectious and fatal neurodegenerative diseases in mammals. Chronic wasting disease (CWD), a prion disease of cervids, spreads efficiently among wild and farmed animals. Potential transmission to humans of CWD is a growing concern due to its increasing prevalence. Here, we provide the strongest evidence to date supporting the zoonotic potential of CWD prions, and their probable materialization in humans using mice expressing human prion protein (PrP) as an infection model. Inoculation of these mice with deer CWD isolates resulted in atypical clinical manifestations, with prion seeding activity and efficient transmissible infectivity in the brain and, remarkably, in feces. Intriguingly, the protease-resistant PrP in the brain resembled that found in a familial human prion disease and was transmissible upon second passage. Our results are the first evidence that CWD can infect humans with a distinctive clinical presentation, signature, and tropism, and 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.
 
Snip...
 
Discussion
Our findings strongly suggest that CWD is an actual public health risk. Here, we use humanized mice to show that CWD prions can cross the species barrier to humans, and remarkably, infectious prions can be excreted in feces.
 
Snip...
 
Our results indicate that if CWD crosses the species-barrier to humans, it is unlikely to resemble the most common forms of human prion diseases with respect to clinical signs, tissue tropism and PrPSc signature. For instance, PrPSc in variable protease sensitive prionopathy (VPSPr), a sporadic form of human prion disease, and the genetic form Gerstmann-Sträussler-Scheinker syndrome (GSS) is defined by an atypical PK-resistant PrPSc fragment that is non-glycosylated and truncated at both C and N termini, with a molecular weight between 6 and 8 kDa 48-51. These biochemical features are unique and distinctive from PrPSc (PrP27-30) found in most other human or animal prion disease. The atypical PrPSc signature detected in brain homogenate of tg650 mice #321 (1st passage) and #3063 (2nd passage), and the 7 – 8 kDa fragment (Figure 2 and 4) are very similar to that of GSS, both in terms of migration profile and the N-terminal cleavage site.
 
Snip...
 
CWD in humans might remain subclinical but with PrPSc deposits in the brain (e.g., mouse #328; Figure 3), clinical with untraceable abnormal PrP (e.g., mouse #327) but still transmissible and uncovered upon subsequent passage (e.g., mouse #3063), or prions have other reservoirs than the usual ones, hence the presence of infectivity in feces (e.g., mouse #327) suggesting a potential for human-to-human transmission and a real iatrogenic risk that might be unrecognizable. 
 
Snip...
 
Taking this into consideration, our study is the strongest proof-of-principal that CWD is transmissible to humans. Using humanized mice, we demonstrated the zoonotic potential of CWD. Furthermore, our findings provide striking insights into how CWD might manifest in humans and the impact it may have on human health. We have used Wisc-1/CWD1, one of the most common CWD strains, notably WTD prions, which have been shown to be more prone to generate human prions in vitro 43. This implies a high risk of exposure to this strain, e.g., through consumption or handling of infected carcasses, in contrast to rarer CWD strains, and therefore, an actual risk for human health. In addition, CWD surveillance in humans should encompass a wider spectrum of tissues/organs tested and include new criteria in the diagnosis of potential patients.
 
 
 
EFSA Panel on Biological Hazards (BIOHAZ) Antonia Ricci Ana Allende Declan Bolton Marianne Chemaly Robert Davies Pablo Salvador Fernández Escámez ... See all authors 
 
First published: 17 January 2018 https://doi.org/10.2903/j.efsa.2018.5132 ; 
 
also, see; 
 
8. Even though human TSEexposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. 
 
***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. 
 
The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers.. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available. 
 
snip... 
 
The tissue distribution of infectivity in CWDinfected cervids is now known to extend beyond CNS and lymphoid tissues. While the removal of these specific tissues from the food chain would reduce human dietary exposure to infectivity, exclusion from the food chain of the whole carcass of any infected animal would be required to eliminate human dietary exposure. 
 
 
 
MONDAY, FEBRUARY 14, 2022 
 
Atypical Nor98 Scrapie, Atypical BSE, CWD, Can Emerge As Different TSE PrP In Cross Species Transmission, A Volatile Situation For Human and Animal Health
 
 
FRIDAY, JANUARY 31, 2020 
 
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
 
 
Thursday, October 28, 2021 
 
Chronic Wasting Disease (CWD) TSE Prion Zoonosis, friendly fire, iatrogenic transmission, blood products, sporadic CJD, what if?
 
 
Thursday, July 29, 2021 
 
TSE PRION OCCUPATIONAL EXPOSURE VIA ANIMAL OR HUMAN, iatrogenic transmission, nvCJD or sCJD, what if? 
 
 
Saturday, February 2, 2019 
 
CWD GSS TSE PRION SPINAL CORD, Confucius Ponders, What if?
 
snip... 
 
 ***> 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) <*** 
 
REVIEW 
 
***> 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) <***
 
Thursday, March 8, 2018 
 
Familial human prion diseases associated with prion protein mutations Y226X and G131V are transmissible to transgenic mice expressing human prion protein
 
 
MONDAY, DECEMBER 16, 2019 
 
Chronic Wasting Disease CWD TSE Prion aka mad cow type disease in cervid Zoonosis Update
 
***> ''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) <***
 
What if?
 
 
TUESDAY, MAY 11, 2021 
 
***> A Unique Presentation of Creutzfeldt-Jakob Disease in a Patient Consuming Deer Antler Velvet <***
 
Conclusion
 
We believe that our patient’s case of CJD is highly suspicious for cervid etiology given the circumstances of the case as well as the strong evidence of plausibility reported in published literature. This is the first known case of CJD in a patient who had consumed deer antler velvet. Despite the confirmed diagnosis of CJD, a causal relationship between the patient’s disease and his consumption of deer antler velvet cannot be definitively concluded.
 
Supplemental data including molecular tissue sample analysis and autopsy findings could yield further supporting evidence. Given this patient’s clinical resemblance to CBD and the known histological similarities of CBD with CJD, clinicians should consider both diseases in the differential diagnosis of patients with a similarly esoteric presentation. Regardless of the origin of this patient’s disease, it is clear that the potential for prion transmission from cervids to humans should be further investigated by the academic community with considerable urgency. 
 
 
''We believe that our patient’s case of CJD is highly suspicious for cervid etiology given the circumstances of the case as well as the strong evidence of plausibility reported in published literature. This is the first known case of CJD in a patient who had consumed deer antler velvet. Despite the confirmed diagnosis of CJD, a causal relationship between the patient’s disease and his consumption of deer antler velvet cannot be definitively concluded.''
 
 
 
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 
 
 
 
***> Please send relevant new references and proposed modifications to the OIE Science Department (scientific.dept@oie.int). <***
 
TUESDAY, MARCH 29, 2022 
 
***> OIE Agent causing chronic wasting disease (CWD) TSE Prion of Cervid <***
 
 
CHRONIC WASTING DISEASE CWD TSE PrP ZOONOSIS ZOONOTIC POTENTIAL AND FREINDLY FIRE THERE FROM IATROGENIC CJD
 
THURSDAY, DECEMBER 16, 2021 
 
Detection of CWD prions in naturally infected white‑tailed deer fetuses and gestational tissues by PMCA
 
 
THURSDAY, DECEMBER 16, 2021 
 
RT‑QuIC detection of CWD prion seeding activity in white‑tailed deer muscle tissues
 
 
ARS RESEARCH Generation of human chronic wasting disease in transgenic mice 
 
Publication Acceptance Date: 9/8/2021
 
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
 
Title: Generation of human chronic wasting disease in transgenic mice
 
Author item WANG, ZERUI - Case Western Reserve University (CWRU) item QIN, KEFENG - University Of Chicago item CAMACHO, MANUEL - Case Western Reserve University (CWRU) item SHEN, PINGPING - Case Western Reserve University (CWRU) item YUAN, JUE - Case Western Reserve University (CWRU) item Greenlee, Justin item CUI, LI - Jilin University item KONG, QINGZHONG - Case Western Reserve University (CWRU) item MASTRIANNI, JAMES - University Of Chicago item ZOU, WEN-QUAN - Case Western Reserve University (CWRU)
 
Submitted to: Acta Neuropathologica Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/8/2021 Publication Date: N/A Citation: N/A
 
Interpretive Summary: Prion diseases are invariably fatal neurologic diseases for which there is no known prevention or cure. Chronic wasting disease (CWD) is the prion disease of deer and elk and is present in farmed and free ranging herds throughout North America. To date there is no clear evidence that the CWD agent could be transmitted to humans. This manuscript describes the use of an in vitro technique, cell-free serial protein misfolding cyclic amplification (sPMCA), to generate a CWD prion that is infectious to transgenic mice expressing the human prion protein. This study provides the first evidence that CWD prions may be able to cause misfolding in the human prion protein. This information will impact medical experts and those involved in making policy for farmed cervids and wildlife.
 
Technical Abstract: Chronic wasting disease (CWD) is a cervid spongiform encephalopathy or prion disease caused by the infectious prion or PrPSc, a misfolded conformer of cellular prion protein (PrPC). It has rapidly spread in North America and also has been found in Asia and Europe. In contrast to the zoonotic mad cow disease that is the first animal prion disease found transmissible to humans, the transmissibility of CWD to humans remains uncertain although most previous studies have suggested that humans may not be susceptible to CWD. Here we report the generation of an infectious human PrPSc by seeding CWD PrPSc in normal human brain PrPC through the in vitro cell-free serial protein misfolding cyclic amplification (sPMCA). Western blotting confirms that the sPMCA-induced proteinase K-resistant PrPSc is a human form, evidenced by a PrP-specific antibody that recognizes human but not cervid PrP. Remarkably, two lines of humanized transgenic (Tg) mice expressing human PrP-129Val/Val (VV) or -129Met/Met (MM) polymorphism develop prion disease at 233 ± 6 (mean ± SE) days post-inoculation (dpi) and 552 ± 27 dpi, respectively, upon intracerebral inoculation with the sPMCA-generated PrPSc. The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns. We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.
 
 
''The brain of diseased Tg mice reveals the electrophoretic profile of PrPSc similar to sporadic Creutzfeldt-Jakob disease (sCJD) MM1 or VV2 subtype but different neuropathological patterns.'' 
 
''We believe that our study provides the first evidence that CWD PrPSc is able to convert human PrPC into PrPSc in vitro and the CWD-derived human PrPSc mimics atypical sCJD subtypes in humanized Tg mice.''
 
Published: 26 September 2021
 
Generation of human chronic wasting disease in transgenic mice
 
Zerui Wang, Kefeng Qin, Manuel V. Camacho, Ignazio Cali, Jue Yuan, Pingping Shen, Justin Greenlee, Qingzhong Kong, James A. Mastrianni & Wen-Quan Zou
 
Acta Neuropathologica Communications volume 9, Article number: 158 (2021)
 
Abstract
 
Chronic wasting disease (CWD) is a cervid prion disease caused by the accumulation of an infectious misfolded conformer (PrPSc) of cellular prion protein (PrPC). It has been spreading rapidly in North America and also found in Asia and Europe. Although bovine spongiform encephalopathy (i.e. mad cow disease) is the only animal prion disease known to be zoonotic, the transmissibility of CWD to humans remains uncertain. Here we report the generation of the first CWD-derived infectious human PrPSc by elk CWD PrPSc-seeded conversion of PrPC in normal human brain homogenates using in vitro protein misfolding cyclic amplification (PMCA). Western blotting with human PrP selective antibody confirmed that the PMCA-generated protease-resistant PrPSc was derived from the human PrPC substrate. Two lines of humanized transgenic mice expressing human PrP with 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 PrPSc patterns and neuropathological changes in the brain. Our study, using PMCA and animal bioassays, provides the first evidence that CWD PrPSc can cross the species barrier to convert human PrPC into infectious PrPSc that can produce bona fide prion disease when inoculated into humanized transgenic mice.
 
Snip...
 
It is worth noting that the annual number of sporadic CJD (sCJD) cases in the USA has increased, with the total number of suspected and confirmed sCJD cases rising from 284 in 2003 to 511 in 2017 (https://www.cdc.gov/prions/cjd/occurrence-transmission.html). The greatly enhanced CJD surveillance and an aging population in the USA certainly contributed to the observed increase in annual sCJD case numbers in recent years, but the possibility cannot be excluded that some of the increased sCJD prevalence is linked to CWD exposure.
 
In the present study, using serial protein misfolding cyclic amplification (sPMCA) assay we generate PrPSc by seeding CWD prions in normal human brain homogenates. Importantly, we reveal that two lines of humanized Tg mice expressing human PrP-129VV and 129MM develop prion diseases upon intracerebral inoculation of the abnormal PrP generated by sPMCA. We believe that our study provides the first opportunity to dissect the clinical, pathological and biochemical features of the CWD-derived human prion disease in two lines of humanized Tg mice expressing two major human PrP genotypes, respectively.
 
 
i thought i might share some news about cwd zoonosis that i got, that i cannot share or post to the public yet, i promised for various reasons, one that it will cause a shit storm for sure, but it was something i really already knew from previous studies, but, i was told that ;
 
==================
 
''As you can imagine, 2 and 5 (especially 5) may raise alarms.  The evidence we have for 4 are not as strong or tight as I would like to have.   At this point, please do not post any of the points publicly yet, but you can refer to points 1-3 in private discussions and all 5 points when discussing with relevant public officials to highlight the long-term risks of CWD zoonosis.''
 
====================
 
so, i figure your as about as official as it gets, and i think this science is extremely important for you to know and to converse about with your officials. it's about to burn a whole in my pocket. this is about as close as it will ever get for cwd zoonosis to be proven in my time, this and what Canada Czub et al found with the Macaques, plus an old study from cjd surveillance unit back that showed cjd and a 9% increase in risk from folks that eat venison, i will post all this below for your files Sir. i remember back in the BSE nvCJD days, from when the first BSE case in bovine was confirmed around 1984 maybe 83, i forget the good vets named that screwed it up first, Carol something, but from 83ish to 95 96 when nvCJD was linked to humans from BSE in cattle, so that took 10 to 15 years. hell, at that rate, especially with Texas and cwd zoonsis, hell, i'll be dead before it's official, if ever, so here ya go Sir. there was a grant study on cwd zoonosis that had been going on for some time, i followed it over the years, then the grant date for said study had expired, so, i thought i would write the good Professor about said study i.e. Professor Kong, CWRU et al. i will post the grant study abstract first, and then after that, what reply i got back, about said study that i was told not to post/publish...
 
CWD ZOONOSIS GRANT FIRST;
 
===============
 
Cervid to human prion transmission
 
Kong, Qingzhong 
 
Case Western Reserve University, Cleveland, OH, United States
 
 Abstract Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. We hypothesize that: (1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; (2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; (3) Reliable essays can be established to detect CWD infection in humans; and (4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. 
 
Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3. 
 
Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1. 
 
Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions. 
 
Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.
 
Public Health Relevance There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.
 
 Funding Agency Agency National Institute of Health (NIH) Institute National Institute of Neurological Disorders and Stroke (NINDS) Type Research Project (R01) Project # 1R01NS088604-01A1 Application # 9037884 Study Section Cellular and Molecular Biology of Neurodegeneration Study Section (CMND) Program Officer Wong, May Project Start 2015-09-30 Project End 2019-07-31 Budget Start 2015-09-30 Budget End 2016-07-31 Support Year 1 Fiscal Year 2015 Total Cost $337,507 Indirect Cost $118,756
 
snip... 
 
 
Professor Kongs reply to me just this month about above grant study that has NOT been published in peer reveiw yet...
 
=================================
 
Here is a brief summary of our findings:
 
snip...can't post, made a promise...tss
 
On Sat, Apr 3, 2021 at 12:19 PM Terry Singeltary <flounder9@verizon.net> wrote:
 
snip...
 
end...tss
 
==============
 
CWD ZOONOSIS THE FULL MONTY TO DATE
 
International Conference on Emerging Diseases, Outbreaks & Case Studies & 16th Annual Meeting on Influenza March 28-29, 2018 | Orlando, USA
 
Qingzhong Kong
 
Case Western Reserve University School of Medicine, USA
 
Zoonotic potential of chronic wasting disease prions from cervids
 
Chronic wasting disease (CWD) is the prion disease in cervids (mule deer, white-tailed deer, American elk, moose, and reindeer). It has become an epidemic in North America, and it has been detected in the Europe (Norway) since 2016. The widespread CWD and popular hunting and consumption of cervid meat and other products raise serious public health concerns, but questions remain on human susceptibility to CWD prions, especially on the potential difference in zoonotic potential among the various CWD prion strains. We have been working to address this critical question for well over a decade. We used CWD samples from various cervid species to inoculate transgenic mice expressing human or elk prion protein (PrP). We found infectious prions in the spleen or brain in a small fraction of CWD-inoculated transgenic mice expressing human PrP, indicating that humans are not completely resistant to CWD prions; this finding has significant ramifications on the public health impact of CWD prions. The influence of cervid PrP polymorphisms, the prion strain dependence of CWD-to-human transmission barrier, and the characterization of experimental human CWD prions will be discussed.
 
Speaker Biography Qingzhong Kong has completed his PhD from the University of Massachusetts at Amherst and Post-doctoral studies at Yale University. He is currently an Associate Professor of Pathology, Neurology and Regenerative Medicine. He has published over 50 original research papers in reputable journals (including Science Translational Medicine, JCI, PNAS and Cell Reports) and has been serving as an Editorial Board Member on seven scientific journals. He has multiple research interests, including public health risks of animal prions (CWD of cervids and atypical BSE of cattle), animal modeling of human prion diseases, mechanisms of prion replication and pathogenesis, etiology of sporadic Creutzfeldt-Jacob disease (CJD) in humans, normal cellular PrP in the biology and pathology of multiple brain and peripheral diseases, proteins responsible for the α-cleavage of cellular PrP, as well as gene therapy and DNA vaccination.
 
 
 
 
 
 
SUNDAY, JULY 25, 2021 
 
North American and Norwegian Chronic Wasting Disease prions exhibit different potential for interspecies transmission and zoonotic risk 
 
''Our data suggest that reindeer and red deer from Norway could be the most transmissible CWD prions to other mammals, whereas North American CWD prions were more prone to generate human prions in vitro.''
 
 
MONDAY, JULY 19, 2021 
 
***> U Calgary researchers at work on a vaccine against a fatal infectious disease affecting deer and potentially people
 
 
Prion Conference 2018 Abstracts
 
BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from. 
 
HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic tranmission to humans there from?
 
Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.
 
Prion Conference 2018 Abstracts
 
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
 
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)
 
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
 
Background
 
Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.
 
Methods
 
Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).
 
Results
 
Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).
 
Conclusions
 
While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.
 
=====
 
P172 Peripheral Neuropathy in Patients with Prion Disease
 
Wang H(1), Cohen M(1), Appleby BS(1,2)
 
(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.
 
Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.
 
We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.
 
Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.
 
=====
 
P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission
 
Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)
 
(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.
 
Background
 
Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.
 
Methods
 
We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.
 
Results
 
We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.
 
Conclusions
 
PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.
 
=====
 
P180 Clinico-pathological analysis of human prion diseases in a brain bank series
 
Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)
 
(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.
 
Background and objective:
 
The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.
 
Methods:
 
We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.
 
Results:
 
176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.
 
Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.
 
Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.
 
Discussion:
 
A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:
 
 
=====
 
P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures
 
Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)
 
(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.
 
Aims:
 
Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.
 
Methods:
 
Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.
 
Results:
 
The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.
 
Conclusions:
 
Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.
 
=====
 
WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
 
Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)
 
(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.
 
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
 
See also poster P103
 
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.
 
=====
 
WA16 Monitoring Potential CWD Transmission to Humans
 
Belay ED
 
Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.
 
The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.
 
=====
 
P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan
 
Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)
 
(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.
 
Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.
 
=====
 
Source Prion Conference 2018 Abstracts
 
 
 
 
Volume 24, Number 8—August 2018 Research Susceptibility of Human Prion Protein to Conversion by Chronic Wasting Disease Prions
 
Marcelo A. BarriaComments to Author , Adriana Libori, Gordon Mitchell, and Mark W. Head Author affiliations: National CJD Research and Surveillance Unit, University of Edinburgh, Edinburgh, Scotland, UK (M.A. Barria, A. Libori, M.W. Head); National and OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada (G. Mitchell)
 
Abstract Chronic wasting disease (CWD) is a contagious and fatal neurodegenerative disease and a serious animal health issue for deer and elk in North America. The identification of the first cases of CWD among free-ranging reindeer and moose in Europe brings back into focus the unresolved issue of whether CWD can be zoonotic like bovine spongiform encephalopathy. We used a cell-free seeded protein misfolding assay to determine whether CWD prions from elk, white-tailed deer, and reindeer in North America can convert the human prion protein to the disease-associated form. We found that prions can convert, but the efficiency of conversion is affected by polymorphic variation in the cervid and human prion protein genes. In view of the similarity of reindeer, elk, and white-tailed deer in North America to reindeer, red deer, and roe deer, respectively, in Europe, a more comprehensive and thorough assessment of the zoonotic potential of CWD might be warranted.
 
snip...
 
Discussion Characterization of the transmission properties of CWD and evaluation of their zoonotic potential are important for public health purposes. Given that CWD affects several members of the family Cervidae, it seems reasonable to consider whether the zoonotic potential of CWD prions could be affected by factors such as CWD strain, cervid species, geographic location, and Prnp–PRNP polymorphic variation. We have previously used an in vitro conversion assay (PMCA) to investigate the susceptibility of the human PrP to conversion to its disease-associated form by several animal prion diseases, including CWD (15,16,22). The sensitivity of our molecular model for the detection of zoonotic conversion depends on the combination of 1) the action of proteinase K to degrade the abundant human PrPC that constitutes the substrate while only N terminally truncating any human PrPres produced and 2) the presence of the 3F4 epitope on human but not cervid PrP. In effect, this degree of sensitivity means that any human PrPres formed during the PMCA reaction can be detected down to the limit of Western blot sensitivity. In contrast, if other antibodies that detect both cervid and human PrP are used, such as 6H4, then newly formed human PrPres must be detected as a measurable increase in PrPres over the amount remaining in the reaction product from the cervid seed. Although best known for the efficient amplification of prions in research and diagnostic contexts, the variation of the PMCA method employed in our study is optimized for the definitive detection of zoonotic reaction products of inherently inefficient conversion reactions conducted across species barriers. By using this system, we previously made and reported the novel observation that elk CWD prions could convert human PrPC from human brain and could also convert recombinant human PrPC expressed in transgenic mice and eukaryotic cell cultures (15).
 
A previous publication suggested that mule deer PrPSc was unable to convert humanized transgenic substrate in PMCA assays (23) and required a further step of in vitro conditioning in deer substrate PMCA before it was able to cross the deer–human molecular barrier (24). However, prions from other species, such as elk (15) and reindeer affected by CWD, appear to be compatible with the human protein in a single round of amplification (as shown in our study). These observations suggest that different deer species affected by CWD could present differing degrees of the olecular compatibility with the normal form of human PrP.
 
The contribution of the polymorphism at codon 129 of the human PrP gene has been extensively studied and is recognized as a risk factor for Creutzfeldt-Jakob disease (4). In cervids, the equivalent codon corresponds to the position 132 encoding methionine or leucine. This polymorphism in the elk gene has been shown to play an important role in CWD susceptibility (25,26). We have investigated the effect of this cervid Prnp polymorphism on the conversion of the humanized transgenic substrate according to the variation in the equivalent PRNP codon 129 polymorphism. Interestingly, only the homologs methionine homozygous seed–substrate reactions could readily convert the human PrP, whereas the heterozygous elk PrPSc was unable to do so, even though comparable amounts of PrPres were used to seed the reaction. In addition, we observed only low levels of human PrPres formation in the reactions seeded with the homozygous methionine (132 MM) and the heterozygous (132 ML) seeds incubated with the other 2 human polymorphic substrates (129 MV and 129 VV). The presence of the amino acid leucine at position 132 of the elk Prnp gene has been attributed to a lower degree of prion conversion compared with methionine on the basis of experiments in mice made transgenic for these polymorphic variants (26). Considering the differences observed for the amplification of the homozygous human methionine substrate by the 2 polymorphic elk seeds (MM and ML), reappraisal of the susceptibility of human PrPC by the full range of cervid polymorphic variants affected by CWD would be warranted.
 
In light of the recent identification of the first cases of CWD in Europe in a free-ranging reindeer (R. tarandus) in Norway (2), we also decided to evaluate the in vitro conversion potential of CWD in 2 experimentally infected reindeer (18). Formation of human PrPres was readily detectable after a single round of PMCA, and in all 3 humanized polymorphic substrates (MM, MV, and VV). This finding suggests that CWD prions from reindeer could be more compatible with human PrPC generally and might therefore present a greater risk for zoonosis than, for example, CWD prions from white-tailed deer. A more comprehensive comparison of CWD in the affected species, coupled with the polymorphic variations in the human and deer PRNP–Prnp genes, in vivo and in vitro, will be required before firm conclusions can be drawn. Analysis of the Prnp sequence of the CWD reindeer in Norway was reported to be identical to the specimens used in our study (2). This finding raises the possibility of a direct comparison of zoonotic potential between CWD acquired in the wild and that produced in a controlled laboratory setting. (Table).
 
The prion hypothesis proposes that direct molecular interaction between PrPSc and PrPC is necessary for conversion and prion replication. Accordingly, polymorphic variants of the PrP of host and agent might play a role in determining compatibility and potential zoonotic risk. In this study, we have examined the capacity of the human PrPC to support in vitro conversion by elk, white-tailed deer, and reindeer CWD PrPSc. Our data confirm that elk CWD prions can convert the human PrPC, at least in vitro, and show that the homologous PRNP polymorphisms at codon 129 and 132 in humans and cervids affect conversion efficiency. Other species affected by CWD, particularly caribou or reindeer, also seem able to convert the human PrP. It will be important to determine whether other polymorphic variants found in other CWD-affected Cervidae or perhaps other factors (17) exert similar effects on the ability to convert human PrP and thus affect their zoonotic potential.
 
Dr. Barria is a research scientist working at the National CJD Research and Surveillance Unit, University of Edinburgh. His research has focused on understanding the molecular basis of a group of fatal neurologic disorders called prion diseases.
 
Acknowledgments We thank Aru Balachandran for originally providing cervid brain tissues, Abigail Diack and Jean Manson for providing mouse brain tissue, and James Ironside for his critical reading of the manuscript at an early stage.
 
This report is independent research commissioned and funded by the United Kingdom’s Department of Health Policy Research Programme and the Government of Scotland. The views expressed in this publication are those of the authors and not necessarily those of the Department of Health or the Government of Scotland.
 
Author contributions: The study was conceived and designed by M.A.B. and M.W.H. The experiments were conducted by M.A.B. and A.L. Chronic wasting disease brain specimens were provided by G.M. The manuscript was written by M.A.B. and M.W.H. All authors contributed to the editing and revision of the manuscript.
 
 
 
Prion 2017 Conference Abstracts
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 
This is a progress report of a project which started in 2009. 
21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. 
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. 
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS ABSTRACTS REFERENCE
8. Even though human TSEexposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
 
 
SATURDAY, FEBRUARY 23, 2019 
 
Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019
 
 
TUESDAY, NOVEMBER 04, 2014 
 
Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011
 
Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "
 
 
Transmission Studies
 
Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases {the following was written but with a single line marked through it ''first passage (by this route)}....TSS
 
resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculum (?saline). Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in ALL of these species with the shortest incubation period in the ferret.
 
snip.... 
 
 
Prion Infectivity in Fat of Deer with Chronic Wasting Disease 
 
Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations
 
In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species. 
 
 
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease 
 
Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure. 
 
 
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.
 
see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”
 
From: TSS 
 
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
 
Date: September 30, 2002 at 7:06 am PST
 
From: "Belay, Ermias"
 
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
 
Sent: Monday, September 30, 2002 9:22 AM
 
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
 
Dear Sir/Madam,
 
In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
 
Ermias Belay, M.D. Centers for Disease Control and Prevention
 
-----Original Message-----
 
From: Sent: Sunday, September 29, 2002 10:15 AM
 
 
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
 
Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS
 
Thursday, April 03, 2008
 
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
 
snip...
 
*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
 
snip... full text ; 
 
 
> However, to date, no CWD infections have been reported in people. 
 
sporadic, spontaneous CJD, 85%+ of all human TSE, did not just happen. never in scientific literature has this been proven.
 
if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;
 
 
 
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry 
 
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
 
> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
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: <3daf5023 .4080804="" wt.net="">
 
Dear Terry,
 
An excellent piece of review as this literature is desparately difficult to get back from Government sites.
 
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
 
Steve Dealler =============== 
 
 
''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 ;
 
 
 
 
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...
 
DEER SPONGIFORM ENCEPHALOPATHY SURVEY
 
3. This will be a low key study with no publicity to avoid unnecessary media interest. It will be carried out in two stages ;
 
(I) A small scale examination of around 30 deer brains to establish the normal histology of the healthy brain; and
 
(II) A larger scale random examination of 300 or more adult deer brains drawn from both deer farms and parks to establish whether there is any evidence of a cervine spongiform encephalopathy. ...
 
 
Ministry of Agriculture Fisheries and Food Veterinary Investigation Centre West House. Station Road. Thirsk Y07 IPZ Telephone: 0845·522065 Fax: 0845·525224
 
Your reference
 
Our reference RJH/ASB
 
Date 4 November 1992
 
DEER SPONGIFORM ENCEPHALOPATHY SURVEY
 
Dear Paul
 
I have now found time to review the 10 deer- brains collected from Mr Walker farm··via Winchester Via Winchester VIC. In answer to your specific question was there sufficient difference in preservation of brain tissue to warrant the extra effort involved in rapid brain removal on the farm, the answer is definitely "Yes." The original five brains (Winchester ref M487/11) showed varying degrees of autolytic vacuolation affecting both white and grey matter throughout the brain. vacuolation and separation of Purkinje cells and marked perivascular spaces. These artifacts made interpretation of subtle, specific pathological vacuolation more difficult. By contrast the second submission (Winchester reference N736/2) showed excellent preservation of white and grey matter. Any vacuolar Change present could be confidently interpreted as pathological albeit of unknown pathogenesis.
 
I can only reiterate the comments made by Gerald Wells and myself at the preliminary discussion at Weybridge in Autumn 1991. If the survey's purpose is an accurate histopathological interpretation of brain tissue. the material must be collected in a pristine state. This is particularly valid when looking for ar unrecognised and undefined spongiform encephalopathy in a new species. Deer brains are very large structures which take a lot of fixation and therefore must be handled sympathetically from the start. We have already seen the problems encountered in comparatively smaller hound brains where delayed fixation was a major limitation on interpretation of true pathological change.
 
The bottom line must be that if a pathologist's expertise is to be used, it is critical to collect artefact free brain material. If the politics or economics do not allow this, then I would suggest that an electron microscopy survey in­volving detection of scrapie associated fibrils would be much more appropriate.
 
Best wishes Yours sincerely
 
R J HIGGINS VIO 92/11.4/2.1
 
 
TSE in wild UK deer? The first case of BSE (as we now realise) was in a nyala in London zoo and the further zoo cases in ungulates were simply thought of as being interesting transmissions of scrapie initially. The big problem started to appear with animals in 1993-5 when it became clear that there was an increase in the CJD cases in people that had eaten deer although the statistics involved must have been questionable. The reason for this was that the CJD Surveillance was well funded to look into the diet of people dying of CJD. This effect is not clear with vCJD...if only because the numbers involved are much smaller and hence it is difficult to gain enough statistics. They found that many other foods did not appear to have much association at all but that deer certainly did and as years went by the association actually became clearer. The appearance of vCJD in 1996 made all this much more difficult in that it was suddenly clearer that the cases of sporadic CJD that they had been checking up until then probably had nothing to do with beef...and the study decreased. During the period there was an increasing worry that deer were involved with CJD.. see references: DEER BRAIN SURVEY
 
 
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: <3daf5023 .4080804="" wt.net="">
 
Dear Terry,
 
An excellent piece of review as this literature is desparately difficult to get back from Government sites.
 
What happened with the deer was that an association between deer meat eating and sporadic CJD was found in about 1993. The evidence was not great but did not disappear after several years of asking CJD cases what they had eaten. I think that the work into deer disease largely stopped because it was not helpful to the UK industry...and no specific cases were reported. Well, if you dont look adequately like they are in USA currenly then you wont find any!
 
Steve Dealler =============== 
 
 
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. 

============== 

https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf 

***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20 

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. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20

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. 

http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160
 
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. 
 
 
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.
 
 
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
 
 
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...
 
 
MONDAY, FEBRUARY 25, 2019
 
***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019
 
 
*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, and there may be asymptomatic individuals infected with the CWD equivalent. ***These circumstances represent a potential threat to blood, blood products, and plasma supplies.
 
 
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) 
 
 
FEDERAL DOCKET CWD SINGELTARY SUBMISSION
 
***> 1st and foremost your biggest problem is 'VOLUNTARY'! AS with the BSE 589.2001 FEED REGULATIONS, especially since it is still voluntary with cervid, knowing full well that cwd and scrapie will transmit to pigs by oral route. VOLUNTARY DOES NOT WORK! all animal products should be banned and be made mandatory, and the herd certification program should be mandatory, or you don't move cervid. IF THE CWD HERD CERTIFICATION IS NOT MANDATORY, it will be another colossal tse prion failure from the start.

***> 2nd USA should declare a Declaration of Extraordinary Emergency due to CWD, and all exports of cervid and cervid products must be stopped internationally, and there should be a ban of interstate movement of cervid, until a live cwd test is available.

***> 3rd Captive Farmed cervid ESCAPEES should be made mandatory to report immediately, and strict regulations for those suspect cwd deer that just happen to disappear. IF a cervid escapes and is not found, that farm should be indefinitely shut down, all movement, until aid MIA cervid is found, and if not ever found, that farm shut down permanently.

***> 4th Captive Farmed Cervid, INDEMNITY, NO MORE Federal indemnity program, or what i call, ENTITLEMENT PROGRAM for game farm industry. NO MORE BAIL OUTS FROM TAX PAYERS. if the captive industry can't buy insurance to protect not only themselves, but also their customers, and especially the STATE, from Chronic Wasting Disease CWD TSE Prion or what some call mad deer disease and harm therefrom, IF they can't afford to buy that insurance that will cover all of it, then they DO NOT GET A PERMIT to have a game farm for anything. This CWD TSE Prion can/could/has caused property values to fall from some reports in some places. roll the dice, how much is a state willing to lose?

***> 5th QUARANTINE OF ALL FARMED CAPTIVE, BREEDERS, URINE, ANTLER, VELVET, SPERM, OR ANY FACILITY, AND THEIR PRODUCTS, that has been confirmed to have Chronic Wasting Disease CWD TSE Prion, the QUARANTINE should be for 21 years due to science showing what scrapie can do. 5 years is NOT near long enough. see; Infectious agent of sheep scrapie may persist in the environment for at least 16 to 21 years.

***> 6th America BSE 589.2001 FEED REGULATIONS CWD TSE Prion

***> 7TH TRUCKING TRANSPORTING CERVID CHRONIC WASTING DISEASE TSE PRION VIOLATING THE LACEY ACT

***> 8TH ALL CAPTIVE FARMING CERVID OPERATIONS MUST BE INSURED TO PAY FOR ANY CLEAN UP OF CWD AND QUARANTINE THERE FROM FOR THE STATE, NO MORE ENTITLEMENT PROGRAM FOR CERVID GAME FARMING PAY TO PLAY FOR CWD TSE PRION OFF THE TAX PAYERS BACK.

***> 9TH ANY STATE WITH DOCUMENTED CWD, INTERSTATE, NATIONAL, AND INTERNATIONAL MOVEMENT OF ALL CERVID, AND ALL CERVID PRODUCTS MUST BE HALTED!

***> 10TH BAN THE SALE OF STRAW BRED BUCKS AND ALL CERVID SEMEN AND URINE PRODUCTS

***> 11th ALL CAPTIVE FARMED CERVID AND THEIR PRODUCTS MUST BE CWD TSE PRION TESTED ANNUALLY AND BEFORE SALE FOR CWD TSE PRION

SEE FULL SCIENCE REFERENCES AND REASONINGS ;
 
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
 
 
 
CWD AND SCRAPIE TRANSMIT TO PIGS BY ORAL ROUTES
 
2021 Transmissible Spongiform Encephalopathy TSE Prion End of Year Report 2020
 
CJD FOUNDATION VIRTUAL CONFERENCE CJD Foundation Research Grant Recipient Reports Panel 2 Nov 3, 2020
 
zoonotic potential of PMCA-adapted CWD PrP 96SS inoculum
 
 
4 different CWD strains, and these 4 strains have different potential to induce any folding of the human prion protein. 
 
 
***> PIGS, WILD BOAR, CWD <***
 
***> POPULATIONS OF WILD BOARS IN THE UNITED STATES INCREASING SUPSTANTUALLY AND IN MANY AREAS WE CAN SEE  A HIGH DENSITY OF WILD BOARS AND HIGH INCIDENT OF CHRONIC WASTING DISEASE
 
HYPOTHOSIS AND SPECIFIC AIMS
 
HYPOTHOSIS 
 
BSE, SCRAPIE, AND CWD, EXPOSED DOMESTIC PIGS ACCUMULATE DIFFERENT QUANTITIES AND STRAINS OF PRIONS IN PERIPHERAL TISSUES, EACH ONE OF THEM WITH PARTICULAR ZOONOTIC POTENTIALS
 
 
Final Report – CJD Foundation Grant Program A. 
 
Project Title: Systematic evaluation of the zoonotic potential of different CWD isolates. Principal Investigator: Rodrigo Morales, PhD.
 
 
Systematic evaluation of the zoonotic potential of different CWD isolates. Rodrigo Morales, PhD Assistant Professor Protein Misfolding Disorders lab Mitchell Center for Alzheimer’s disease and Related Brain Disorders Department of Neurology University of Texas Health Science Center at Houston Washington DC. July 14th, 2018
 
Conclusions and Future Directions • We have developed a highly sensitive and specific CWD-PMCA platform to be used as a diagnostic tool. • Current PMCA set up allow us to mimic relevant prion inter-species transmission events. • Polymorphic changes at position 96 of the prion protein apparently alter strain properties and, consequently, the zoonotic potential of CWD isolates. • Inter-species and inter-polymorphic PrPC → PrPSc conversions further increase the spectrum of CWD isolates possibly present in nature. • CWD prions generated in 96SS PrPC substrate apparently have greater inter-species transmission potentials. • Future experiments will explore the zoonotic potential of CWD prions along different adaptation scenarios, including inter-species and inter-polymorphic.
 
 
 
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research
 
Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease 
 
Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
 
 
 
Research Project: Pathobiology, Genetics, and Detection of Transmissible Spongiform Encephalopathies Location: Virus and Prion Research
 
Title: The agent of chronic wasting disease from pigs is infectious in transgenic mice expressing human PRNP 
 
Author item MOORE, S - Orise Fellow item Kokemuller, Robyn item WEST-GREENLEE, M - Iowa State University item BALKEMA-BUSCHMANN, ANNE - Friedrich-Loeffler-institut item GROSCHUP, MARTIN - Friedrich-Loeffler-institut item Greenlee, Justin Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 5/10/2018 Publication Date: 5/22/2018 Citation: Moore, S.J., Kokemuller, R.D., West-Greenlee, M.H., Balkema-Buschmann, A., Groschup, M.H., Greenlee, J.J. 2018. The agent of chronic wasting disease from pigs is infectious in transgenic mice expressing human PRNP. Prion 2018, Santiago de Compostela, Spain, May 22-25, 2018. Paper No. WA15, page 44.
 
Interpretive Summary:
 
 The successful transmission of pig-passaged CWD to Tg40 mice reported here suggests that passage of the CWD agent through pigs results in a change of the transmission characteristics which reduces the transmission barrier of Tg40 mice to the CWD agent. If this biological behavior is recapitulated in the original host species, passage of the CWD agent through pigs could potentially lead to increased pathogenicity of the CWD agent in humans.
 
 
cwd scrapie pigs oral routes 
 
***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <*** 
 
>*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <*** 
 
***> Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 oral >6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 
 
***> Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains. 
 
 
 
 
Conclusions: This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge. CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period. This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease. Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
 
 
CONFIDENTIAL
 
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
 
LINE TO TAKE
 
3. If questions on pharmaceuticals are raised at the Press conference, the suggested line to take is as follows:- 
 
 "There are no medicinal products licensed for use on the market which make use of UK-derived porcine tissues with which any hypothetical “high risk" ‘might be associated. The results of the recent experimental work at the CSM will be carefully examined by the CSM‘s Working Group on spongiform encephalopathy at its next meeting.
 
DO Hagger RM 1533 MT Ext 3201
 
 
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
 
 
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
 
 
May I, at the outset, reiterate that we should avoid dissemination of papers relating to this experimental finding to prevent premature release of the information. ...
 
 
3. It is particularly important that this information is not passed outside the Department, until Ministers have decided how they wish it to be handled. ...
 
 
But it would be easier for us if pharmaceuticals/devices are not directly mentioned at all. ...
 
 
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
 
 
cattle are highly susceptible to white-tailed deer CWD and mule deer CWD
 
***In contrast, cattle are highly susceptible to white-tailed deer CWD and mule deer CWD in experimental conditions but no natural CWD infections in cattle have been reported (Sigurdson, 2008; Hamir et al., 2006). It is not known how susceptible humans are to CWD but given that the prion can be present in muscle, it is likely that humans have been exposed to the agent via consumption of venison (Sigurdson, 2008). Initial experimental research, however, suggests that human susceptibility to CWD is low and there may be a robust species barrier for CWD transmission to humans (Sigurdson, 2008). It is apparent, though, that CWD is affecting wild and farmed cervid populations in endemic areas with some deer populations decreasing as a result.
 
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 ***
 
 
***> 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) 
 

Susceptibility of Beavers to Chronic Wasting Disease

by Allen Herbst 1,2,3,Serene Wohlgemuth 2,4,Jing Yang 2,4,Andrew R. Castle 2,4ORCID,Diana Martinez Moreno 2,5,Alicia Otero 6ORCID,Judd M. Aiken 2,3,David Westaway 2,4 andDebbie McKenzie 2,5,*

1 U.S. Geological Survey National Wildlife Health Center, Madison, WI 53711, USA 2 Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2R3, Canada 3 Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2R3, Canada 4 Department of Medicine, University of Alberta, Edmonton, AB T6G 2R3, Canada 5 Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2R3, Canada 6 Centro de Encefalopatias y Enfermedades Transmisibles Emergentes, University of Zaragoza, 50009 Zaragoza, Spain * Author to whom correspondence should be addressed. Academic Editor: Walker Jackson

Biology 2022, 11(5), 667; https://doi.org/10.3390/biology11050667 (registering DOI)

Received: 18 March 2022 / Revised: 16 April 2022 / Accepted: 20 April 2022 / Published: 26 April 2022

(This article belongs to the Special Issue Selective Vulnerability in Neurodegenerative Diseases)

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Simple Summary

Chronic wasting disease is increasing across the landscape, and this is threatening other wildlife species in addition to cervids. Our objective was to evaluate the possibility that chronic wasting disease could transmit to beavers. Our results indicate that beavers are susceptible to multiple types of prion diseases, including chronic wasting disease.

Abstract

Chronic wasting disease (CWD) is a contagious, fatal, neurodegenerative prion disease of cervids. The expanding geographical range and rising prevalence of CWD are increasing the risk of pathogen transfer and spillover of CWD to non-cervid sympatric species. As beavers have close contact with environmental and food sources of CWD infectivity, we hypothesized that they may be susceptible to CWD prions. We evaluated the susceptibility of beavers to prion diseases by challenging transgenic mice expressing beaver prion protein (tgBeaver) with five strains of CWD, four isolates of rodent-adapted prions and one strain of Creutzfeldt–Jakob disease. All CWD strains transmitted to the tgBeaver mice, with attack rates highest from moose CWD and the 116AG and H95+ strains of deer CWD. Mouse-, rat-, and especially hamster-adapted prions were also transmitted with complete attack rates and short incubation periods. We conclude that the beaver prion protein is an excellent substrate for sustaining prion replication and that beavers are at risk for CWD pathogen transfer and spillover.

Keywords: prions; chronic wasting disease; beavers; wildlife diseases

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4. Discussion

Transgenic mice expressing beaver PrPC are susceptible to multiple prion strains, after intracranial challenge, including those that cause CWD. Strain-specific attack rates and incubation periods were observed in the tgBeaver mice, with the H95+ strain showing the highest virulence among the CWD strains tested. Transmission of the CWD isolates was associated with protracted and variable incubation periods and variable attack rates, as is typical for first passage interspecies transmission of prions. No correlation was apparent in the degree of homology between PrPC in the donor and recipient animals and transmission. Beaver PrPC has the highest homology to human PrPC (92.5%), as compared to the rodents, yet the human CJD prions obtained by passage in tgHuman mice did not result in clinical or subclinical infections. By contrast, the rodent prions had the highest attack rates and shortest incubation periods, even though the sequence homology was the lowest (Figure S2). With the exception of CJD transmission, higher attack rates and shorter incubation periods were observed when the source prion strain was derived from rodents. For example, Wisc-1 prions from deer transmitted poorly compared to the same prion strain passaged in the tg33 transgenic cervid mice. Rodents typically accumulate very high titres of prion infectivity per gram of brain tissue and the higher concentration of prions in the inocula from the cervidized mice may have facilitated transmission.

After the prion inoculation experiments were initiated, we noted that all transgenepositive offspring of crosses between transgene-positive males and Prnp-knockout females were female, indicating that the tgBeaver PrP expression transgene had integrated into the X-chromosome. While sex-specific differences in prion transmissions are per se thought to be minor [54], due to X-inactivation, it is possible that the female transgenic mice had lower PrPC expression levels than the male transgenics. This could explain the tendency for female mice to display longer and more variable incubation periods for most (although not all) of the prion agents tested.

Intracranial infection is a gold-standard laboratory method to measure the molecular barrier between a recipient PrPC and an invading prion strain; however, this approach alone cannot determine the risk of pathogen transfer, which also requires exposure. CWD is geographically expanding, increasing its prevalence within endemic regions, and increasing CWD prion environmental contamination [55]. These factors are increasing the exposure of all sympatric species to CWD prions, including beavers, and driving the risk of interspecies transmission of CWD. High levels of exposure can override even strong species barriers, as was shown by the transmission of bovine spongiform encephalopathy to humans. CWD prion transfer to beavers may result in pathogen spillover facilitated by long beaver lifespans (>20 years) that would enable CWD adaptation and shedding and social interactions that would facilitate transmission.

Transmission studies demonstrate that CWD prions can infect a variety of other species including cattle, sheep, pigs, ferrets, hamsters, red-backed and bank voles, and whitefooted mice. Our data indicate that beavers also are expected to be susceptible to CWD and at risk for pathogen transfer and spillover. We are unaware of any attempt to perform surveillance for prion disease in wild beavers. Targeted or opportunistic surveillance of wild beavers in areas where CWD, in cervids, has reached high prevalence would further clarify the risk of CWD to beavers.



TUESDAY, APRIL 26, 2022 

Susceptibility of Beavers to Chronic Wasting Disease 

 
FRIDAY, FEBRUARY 11, 2022 
 
Passage of the CWD agent through meadow voles results in increased attack rates and decreased incubation periods in raccoons
 

223. Scrapie in white-tailed deer: a strain of the CWD agent that efficiently transmits to sheep?

Justin J. Greenleea, Robyn D. Kokemullera, S. Jo Moorea and Heather West Greenleeb

aVirus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA, USA; bDepartment of Biomedical Sciences, Iowa State University College of Veterinary Medicine, Ames, IA, USA

CONTACT Justin J. Greenlee Justin.Greenlee@ars.usda.gov

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 deposits. 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 identification of CWD strains in deer and the eradication of scrapie from sheep.


TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION MAD COW TYPE DISEASE

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

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Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field.

snip...


***> This is very likely to have parallels with control efforts for CWD in cervids. <***

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

Abstract

The transmissible spongiform encephalopathy scrapie of sheep/goats and chronic wasting disease of cervids are associated with environmental reservoirs of infectivity. Preventing environmental prions acting as a source of infectivity to healthy animals is of major concern to farms that have had outbreaks of scrapie and also to the health management of wild and farmed cervids. Here, an efficient scrapie decontamination protocol was applied to a farm with high levels of environmental contamination with the scrapie agent. Post‐decontamination, no prion material was detected within samples taken from the farm buildings as determined using a sensitive in vitro replication assay (sPMCA). A bioassay consisting of 25 newborn lambs of highly susceptible prion protein genotype VRQ/VRQ introduced into this decontaminated barn was carried out in addition to sampling and analysis of dust samples that were collected during the bioassay. Twenty‐four of the animals examined by immunohistochemical analysis of lymphatic tissues were scrapie‐positive during the bioassay, samples of dust collected within the barn were positive by month 3. The data illustrates the difficulty in decontaminating farm buildings from scrapie, and demonstrates the likely contribution of farm dust to the recontamination of these environments to levels that are capable of causing disease.

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This study clearly demonstrates the difficulty in removing scrapie infectivity from the farm environment. Practical and effective prion decontamination methods are still urgently required for decontamination of scrapie infectivity from farms that have had cases of scrapie and this is particularly relevant for scrapiepositive goatherds, which currently have limited genetic resistance to scrapie within commercial breeds.24 This is very likely to have parallels with control efforts for CWD in cervids.


***>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

1Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK

2Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK

3Surveillance and Laboratory Services, Animal and Plant Health Agency Penrith, Penrith, UK

4ADAS UK, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK

5School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK

Classical scrapie is an environmentally transmissible prion disease of sheep and goats. Prions can persist and remain potentially infectious in the environment for many years and thus pose a risk of infecting animals after re-stocking. In vitro studies using serial protein misfolding cyclic amplification (sPMCA) have suggested that objects on a scrapie-affected sheep farm could contribute to disease transmission. This in vivo study aimed to determine the role of field furniture (water troughs, feeding troughs, fencing, and other objects that sheep may rub against) used by a scrapie-infected sheep flock as a vector for disease transmission to scrapie-free lambs with the prion protein genotype VRQ/VRQ, which is associated with high susceptibility to classical scrapie. When the field furniture was placed in clean accommodation, sheep became infected when exposed to either a water trough (four out of five) or to objects used for rubbing (four out of seven). This field furniture had been used by the scrapie-infected flock 8 weeks earlier and had previously been shown to harbor scrapie prions by sPMCA. Sheep also became infected (20 out of 23) through exposure to contaminated field furniture placed within pasture not used by scrapie-infected sheep for 40 months, even though swabs from this furniture tested negative by PMCA. This infection rate decreased (1 out of 12) on the same paddock after replacement with clean field furniture. Twelve grazing sheep exposed to field furniture not in contact with scrapie-infected sheep for 18 months remained scrapie free. 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 

Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20). 

Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22). 

Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23). 

Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing. 

Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building. 

Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9). 

The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture. 

When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier. 

This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep. 

Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease. 

It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled. 

Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases. 

Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA. 

Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions. 

PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice. 

In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals. 

In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions). 

As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay. 

False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28). 

This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm. 

This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc. 

In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc. 

Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing. 

The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material. 

In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12). 

A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30). 

This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model. 

Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions. 

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. 

These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes. 

Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification 


***> 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.


KOREA CWD UPDATE 2022

FRIDAY, MARCH 18, 2022 

Korea Chronic Wasting Disease CWD TSE PrP Update Increase of Positive Cases and Polymorphisms of the prion-related protein gene 

IN 235 elks, 22 elks (9.4%) were infected with CWD.

IN 257 red deer, 78 red deer (30.4%) were infected with CWD.

IN 150 sika deer, 16 sika deer (10.7%) were infected with CWD.


THURSDAY, MARCH 03, 2022 

Norway More of the NON-CONTAGIOUS Scrapie (CWD) TSE Prion Disease Keeps Mounting? 


MONDAY, JANUARY 17, 2022 

Norway Infamous, Mysterious, Spontaneous, Sporadic, atypical, BSE, CWD, Scrapie, TSE, Prion, Outbreak Update 


SUNDAY, JULY 25, 2021 

North American and Norwegian Chronic Wasting Disease prions exhibit different potential for interspecies transmission and zoonotic risk 

''Our data suggest that reindeer and red deer from Norway could be the most transmissible CWD prions to other mammals, whereas North American CWD prions were more prone to generate human prions in vitro.''


***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018
P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer 

Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1) 

(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada. 

Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer. 

Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection. 

Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD. 

SOURCE REFERENCE 2018 PRION CONFERENCE ABSTRACT

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research

Title: Horizontal transmission of chronic wasting disease in reindeer

Author

item MOORE, SARAH - ORISE FELLOW item KUNKLE, ROBERT item WEST GREENLEE, MARY - IOWA STATE UNIVERSITY item Nicholson, Eric item RICHT, JUERGEN item HAMIR, AMIRALI item WATERS, WADE item Greenlee, Justin

Submitted to: Emerging Infectious Diseases

Publication Type: Peer Reviewed Journal

Publication Acceptance Date: 8/29/2016

Publication Date: 12/1/2016

Citation: Moore, S., Kunkle, R., Greenlee, M., Nicholson, E., Richt, J., Hamir, A., Waters, W., Greenlee, J. 2016. Horizontal transmission of chronic wasting disease in reindeer. Emerging Infectious Diseases. 22(12):2142-2145. doi:10.3201/eid2212.160635.

Interpretive Summary: Chronic wasting disease (CWD) is a fatal neurodegenerative disease that occurs in farmed and wild cervids (deer and elk) of North America and was recently diagnosed in a single free-ranging reindeer (Rangifer tarandus tarandus) in Norway. CWD is a transmissible spongiform encephalopathy (TSE) that is caused by infectious proteins called prions that are resistant to various methods of decontamination and environmental degradation. Little is known about the susceptibility of or potential for transmission amongst reindeer. In this experiment, we tested the susceptibility of reindeer to CWD from various sources (elk, mule deer, or white-tailed deer) after intracranial inoculation and tested the potential for infected reindeer to transmit to non-inoculated animals by co-housing or housing in adjacent pens. Reindeer were susceptible to CWD from elk, mule deer, or white-tailed deer sources after experimental inoculation. Most importantly, non-inoculated reindeer that were co-housed with infected reindeer or housed in pens adjacent to infected reindeer but without the potential for nose-to-nose contact also developed evidence of CWD infection. This is a major new finding that may have a great impact on the recently diagnosed case of CWD in the only remaining free-ranging reindeer population in Europe as our findings imply that horizontal transmission to other reindeer within that herd has already occurred. Further, this information will help regulatory and wildlife officials developing plans to reduce or eliminate CWD and cervid farmers that want to ensure that their herd remains CWD-free, but were previously unsure of the potential for reindeer to transmit CWD.

Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal prion disease of cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, and CWD was recently reported in a free-ranging reindeer of Norway. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWDwtd), mule deer (Odocoileus hemionus; CWDmd), or elk (Cervus elaphus nelsoni; CWDelk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWDwtd, CWDmd, or CWDelk. Two years after challenge of inoculated reindeer, non-inoculated negative control reindeer were introduced into the same pen as the CWDwtd inoculated reindeer (direct contact; n=4) or into a pen adjacent to the CWDmd inoculated reindeer (indirect contact; n=2). Experimentally inoculated reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrPcwd). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (months PI). PrPcwd was detected in 5 out of 6 sentinel reindeer although only 2 out of 6 developed clinical disease during the study period (< 57 months PI). We have shown that reindeer are susceptible to CWD from various cervid sources and can transmit CWD to naïve reindeer both directly and indirectly.


Infectivity surviving ashing to 600*C is (in my opinion) degradable but infective. based on Bown & Gajdusek, (1991), landfill and burial may be assumed to have a reduction factor of 98% (i.e. a factor of 50) over 3 years. CJD-infected brain-tissue remained infectious after storing at room-temperature for 22 months (Tateishi et al, 1988). Scrapie agent is known to remain viable after at least 30 months of desiccation (Wilson et al, 1950). and pastures that had been grazed by scrapie-infected sheep still appeared to be contaminated with scrapie agent three years after they were last occupied by sheep (Palsson, 1979).


Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document


Pathogens. 2020 Apr; 9(4): 311.

Published online 2020 Apr 23. doi: 10.3390/pathogens9040311

PMCID: PMC7238116

PMID: 32340296

Long-Term Incubation PrPCWD with Soils Affects Prion Recovery but Not Infectivity

Alsu Kuznetsova,1 Debbie McKenzie,2 Catherine Cullingham,3 and Judd M. Aiken1,*

Abstract

Chronic wasting disease (CWD) is a contagious prion disease of cervids. The infectious agent is shed from animals at the preclinical and clinical stages of disease where it persists in the environment as a reservoir of CWD infectivity. In this study, we demonstrate that long-term incubation of CWD prions (generated from tg-mice infected with deer or elk prions) with illite, montmorillonite (Mte) and whole soils results in decreased recovery of PrPCWD, suggesting that binding becomes more avid and irreversible with time. This continual decline of immunoblot PrPCWD detection did not correlate with prion infectivity levels. Bioassay showed no significant differences in incubation periods between mice inoculated with 1% CWD brain homogenate (BH) and with the CWD-BH pre-incubated with quartz or Luvisolic Ae horizon for 1 or 30 weeks. After 55 weeks incubation with Chernozem and Luvisol, bound PrPCWD was not detectable by immunoblotting but remained infectious. This study shows that although recovery of PrPCWD bound to soil minerals and whole soils with time become more difficult, prion infectivity is not significantly altered. Detection of prions in soil is, therefore, not only affected by soil type but also by length of time of the prion–soil interaction.

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4. Conclusions

The binding of prions to soil minerals and other soil constituents impacts PrPCWD recovery. During extended incubation with soils, PrP signal on immunoblots continuously declined until it was no longer detectable after 25 weeks in soils with loamy-clay texture and Mte minerology. PrPCWD infectivity did not, however, decrease after 30 weeks incubation with quartz and the Luvisolic Ae soil horizon. At 55 weeks incubation in Chernozem and Luvisol, CWD-BH remained infectious. We studied a wide variety of soil types (from prairie, mountain and boreal regions) and showed decreased PrPCWD signal recovery (as measured by immunoblotting) with retention of infectivity. The decrease in PrPCWD recovery was particularly dramatic in soils from the prairie region. Regardless of soil minerology, texture and humus content, detection of PrPCWD in environmental soil samples is a challenge after long-term incubation. These findings provide important information on the behavior of prions in natural environments, but complicate analysis of environmental samples.

Keywords: prion protein, soil, CWD, prolonged incubation, CWD infectivity, prion detection


Prion. 2012 Jul 1; 6(3): 302–308. doi: 10.4161/pri.20025 PMCID: PMC3399538 PMID: 22561162

Temperature influences the interaction of ruminant PrPTSE with soil

Ben C. Maddison, 1 Jonathan P. Owen, 1 Maged A. Taema, 2 George Shaw, 3 and Kevin C. Gough 2 , *

Abstract

Ovine scrapie and cervid chronic wasting disease can be transmitted in the absence of animal-to-animal contact, and environmental reservoirs of infectivity have been implicated in their spread and persistence. Investigating environmental factors that influence the interaction of disease-associated PrP with soils is imperative to understanding what is likely to be the complex role of soil in disease transmission. Here, we describe the effects of soil temperature on the binding/desorption and persistence of both ovine scrapie- and bovine BSE-PrPTSE. Binding of PrPTSE to a sandy loam soil at temperatures of 4°C, 8–12°C and 25–30°C demonstrated that an increase in temperature resulted in (1) a decrease in the amount of PrPTSE recovered after 24 h of interaction with soil, (2) an increase in the amount of N-terminal cleavage of the prion protein over 11 d and (3) a decrease in the persistence of PrPTSE on soil over an 18 mo period.

snip...

In the present study we investigated the effects of soil temperature in the range 4°C to 30°C on the interaction of BSE- and scrapie-PrPTSE with a complex soil matrix. Lower soil temperatures resulted in increased levels of PrPTSE recovery and persistence over an 18-mo incubation period. A low soil temperature also resulted in less cleavage of the N-terminal domain of PrPTSE after an 11-d interaction. These effects of temperature on PrPTSE-soil interaction were likely to be exerted through both microbial activity and abiotic cleavage mechanisms. Together, the data indicate that for the recoverable fraction of PrPTSE, soils at lower temperature may release increased levels of PrPTSE.

A recent study using transmissible mink encephalopathy reported a correlation between the level of desorption of PrPTSE from soil and the infectivity titer of the sample.25 If such a correlation is also true for ovine scrapie and bovine BSE, the data presented here indicate that the bioavailability of prions in soil for the environmental transmission of scrapie or BSE may be influenced by the temperature of the soil. However, it remains to be seen whether the reported influence of temperature on prion interaction with a sandy-loam soil is consistent with other soil types. Of course, it should also be considered that temperature would be just one of a range of factors influencing the bioavailability of prions from soil; other factors would likely include soil type, prion strain and the biological matrix of the prion source. Scrapie and CWD are known to be spread by environmental routes and therefore understanding the range of factors that influence the persistence of environmental prions is vital in developing eradication programmes.

Keywords: BSE, environment, prion, scrapie, soil, transmission


Using in vitro Prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission. 

Claudio Soto Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston. 

Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.

=========================

***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.

========================

Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis. 

source reference Prion Conference 2015 abstract book

Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions

Sandra Pritzkow,1 Rodrigo Morales,1 Fabio Moda,1,3 Uffaf Khan,1 Glenn C. Telling,2 Edward Hoover,2 and Claudio Soto1, * 1Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA

2Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA

3Present address: IRCCS Foundation Carlo Besta Neurological Institute, 20133 Milan, Italy *Correspondence: claudio.soto@uth.tmc.edu http://dx.doi.org/10.1016/j.celrep.2015.04.036

SUMMARY

Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrPSc) to plants. Small quantities of PrPSc contained in diluted brain homogenate or in excretory materials (urine and feces) can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrPSc for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves). These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease.

INTRODUCTION

snip...

DISCUSSION

This study shows that plants can efficiently bind prions contained in brain extracts from diverse prion infected animals, including CWD-affected cervids. PrPSc attached to leaves and roots from wheat grass plants remains capable of seeding prion replication in vitro. Surprisingly, the small quantity of PrPSc naturally excreted in urine and feces from sick hamster or cervids was enough to efficiently contaminate plant tissue. Indeed, our results suggest that the majority of excreted PrPSc is efficiently captured by plants’ leaves and roots. Moreover, leaves can be contaminated by spraying them with a prion-containing extract, and PrPSc remains detectable in living plants for as long as the study was performed (several weeks). Remarkably, prion contaminated plants transmit prion disease to animals upon ingestion, producing a 100% attack rate and incubation periods not substantially longer than direct oral administration of sick brain homogenates.

Finally, an unexpected but exciting result was that plants were able to uptake prions from contaminated soil and transport them to aerial parts of the plant tissue. Although it may seem farfetched that plants can uptake proteins from the soil and transport it to the parts above the ground, there are already published reports of this phenomenon (McLaren et al., 1960; Jensen and McLaren, 1960;Paungfoo-Lonhienne et al., 2008). The high resistance of prions to degradation and their ability to efficiently cross biological barriers may play a role in this process. The mechanism by which plants bind, retain, uptake, and transport prions is unknown. We are currently studying the way in which prions interact with plants using purified, radioactively labeled PrPSc to determine specificity of the interaction, association constant, reversibility, saturation, movement, etc.

Epidemiological studies have shown numerous instances of scrapie or CWD recurrence upon reintroduction of animals on pastures previously exposed to prion-infected animals. Indeed, reappearance of scrapie has been documented following fallow periods of up to 16 years (Georgsson et al., 2006), and pastures were shown to retain infectious CWD prions for at least 2 years after exposure (Miller et al., 2004). It is likely that the environmentally mediated transmission of prion diseases depends upon the interaction of prions with diverse elements, including soil, water, environmental surfaces, various invertebrate animals, and plants.

However, since plants are such an important component of the environment and also a major source of food for many animal species, including humans, our results may have far-reaching implications for animal and human health. Currently, the perception of the riskfor animal-to-human prion transmission has beenmostly limited to consumption or exposure to contaminated meat; our results indicate that plants might also be an important vector of transmission that needs to be considered in risk assessment. 


Published: 07 October 2021

Review on PRNP genetics and susceptibility to chronic wasting disease of Cervidae

Katayoun Moazami-Goudarzi, Olivier Andréoletti, Jean-Luc Vilotte & Vincent Béringue 

Veterinary Research volume 52, Article number: 128 (2021) Cite this article

Abstract

To date, chronic wasting disease (CWD) is the most infectious form of prion disease affecting several captive, free ranging and wild cervid species. Responsible for marked population declines in North America, its geographical spread is now becoming a major concern in Europe. Polymorphisms in the prion protein gene (PRNP) are an important factor influencing the susceptibility to prions and their rate of propagation. All reported cervid PRNP genotypes are affected by CWD. However, in each species, some polymorphisms are associated with lower attack rates and slower progression of the disease. This has potential consequences in terms of genetic selection, CWD diffusion and strain evolution. CWD also presents a zoonotic risk due to prions capacity to cross species barriers. This review summarizes our current understanding of CWD control, focusing on PRNP genetic, strain diversity and capacity to infect other animal species, including humans.

snip...

CWD positive animals with extended time before they succumb to disease likely represent a source of chronic prion shedding within populations and may contribute to environmental contamination. 


***> CWD positive animals with extended time before they succumb to disease likely represent a source of chronic prion shedding within populations and may contribute to environmental contamination. <***

Genes (Basel) . 2021 Sep 10;12(9):1396. doi: 10.3390/genes12091396.

Selective Breeding for Disease-Resistant PRNP Variants to Manage Chronic Wasting Disease in Farmed Whitetail Deer

Nicholas Haley 1, Rozalyn Donner 1, Kahla Merrett 1, Matthew Miller 1, Kristen Senior 1

Affiliations expand

PMID: 34573378 DOI: 10.3390/genes12091396

Abstract

Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy (TSE) of cervids caused by a misfolded variant of the normal cellular prion protein, and it is closely related to sheep scrapie. Variations in a host's prion gene, PRNP, and its primary protein structure dramatically affect susceptibility to specific prion disorders, and breeding for PRNP variants that prevent scrapie infection has led to steep declines in the disease in North American and European sheep. While resistant alleles have been identified in cervids, a PRNP variant that completely prevents CWD has not yet been identified. Thus, control of the disease in farmed herds traditionally relies on quarantine and depopulation. In CWD-endemic areas, depopulation of private herds becomes challenging to justify, leading to opportunities to manage the disease in situ. We developed a selective breeding program for farmed white-tailed deer in a high-prevalence CWD-endemic area which focused on reducing frequencies of highly susceptible PRNP variants and introducing animals with less susceptible variants. With the use of newly developed primers, we found that breeding followed predictable Mendelian inheritance, and early data support our project's utility in reducing CWD prevalence. This project represents a novel approach to CWD management, with future efforts building on these findings.

Keywords: CWD; PRNP; deer; prion; resistance; selective breeding; susceptibility.


***> While resistant alleles have been identified in cervids, a PRNP variant that completely prevents CWD has not yet been identified.

In Moore et al., reindeer carrying allele E had longer survival-times following intracranial exposure [24]. In the same experiment, a reindeer with a genotype carrier of E, found dead without showing clinical signs ~13 months post-intracranial inoculation, had no histopathological lesions or PrPSc deposition at post-mortem examination.

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Our data support the notion that PRNP genetic variation modulates CWD susceptibility rather than conferring complete resistance. This is in agreement with experimental observations of reindeer-developing CWD after intracranial inoculation regardless of PRNP genotype [24].


***> Our data support the notion that PRNP genetic variation modulates CWD susceptibility rather than conferring complete resistance. 

 Published: 27 May 2021

White-tailed deer S96 prion protein does not support stable in vitro propagation of most common CWD strains

Alicia Otero, Camilo Duque Velásquez, Judd Aiken & Debbie McKenzie 

Scientific Reports volume 11, Article number: 11193 (2021) Cite this article

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Abstract

PrPC variation at residue 96 (G/S) plays an important role in the epidemiology of chronic wasting disease (CWD) in exposed white-tailed deer populations. In vivo studies have demonstrated the protective effect of serine at codon 96, which hinders the propagation of common CWD strains when expressed in homozygosis and increases the survival period of S96/wt heterozygous deer after challenge with CWD. Previous in vitro studies of the transmission barrier suggested that following a single amplification step, wt and S96 PrPC were equally susceptible to misfolding when seeded with various CWD prions. When we performed serial prion amplification in vitro using S96-PrPC, we observed a reduction in the efficiency of propagation with the Wisc-1 or CWD2 strains, suggesting these strains cannot stably template their conformations on this PrPC once the primary sequence has changed after the first round of replication. Our data shows the S96-PrPC polymorphism is detrimental to prion conversion of some CWD strains. These data suggests that deer homozygous for S96-PrPC may not sustain prion transmission as compared to a deer expressing G96-PrPC.

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The protective effect of S96 and H95 alleles was further demonstrated by experimental oral infection in white-tailed deer expressing these amino acid substitutions19. Among the alleles of the PRNP gene associated with a lower CWD incidence and extended preclinical phase, S96 has the highest allelic frequency (~ 25%) after the wt allele in several white-tailed deer populations from the United States and Canada26,27,31. Subsequent independent transmission and epidemiological studies have demonstrated that deer homozygous and heterozygous for S96-PrPC are, compared to wt/wt deer, less susceptible to CWD infection, present prolonged survival times, show delayed prion accumulation and are generally at a significantly earlier stage of disease when deer herds are depopulated23,31,32,33.


***> Subsequent independent transmission and epidemiological studies have demonstrated that deer homozygous and heterozygous for S96-PrPC are, compared to wt/wt deer, less susceptible to CWD infection, present prolonged survival times,

Prion protein polymorphisms associated with reduced CWD susceptibility limit peripheral PrPCWD deposition in orally infected white-tailed deer

Alicia Otero1 , Camilo Duque Velásquez4,5, Chad Johnson3 , Allen Herbst2,5, Rosa Bolea1 , Juan José Badiola1 , Judd Aiken2,5 and Debbie McKenzie4,5*

Abstract

Background: Chronic wasting disease (CWD) is a prion disease affecting members of the Cervidae family. PrPC primary structures play a key role in CWD susceptibility resulting in extended incubation periods and regulating the propagation of CWD strains. We analyzed the distribution of abnormal prion protein (PrPCWD) aggregates in brain and peripheral organs from orally inoculated white-tailed deer expressing four different PRNP genotypes: Q95G96/ Q95G96 (wt/wt), S96/wt, H95/wt and H95/S96 to determine if there are substantial differences in the deposition pattern of PrPCWD between different PRNP genotypes.

Results: Although we detected differences in certain brain areas, globally, the different genotypes showed similar PrPCWD deposition patterns in the brain. However, we found that clinically affected deer expressing H95 PrPC , despite having the longest survival periods, presented less PrPCWD immunoreactivity in particular peripheral organs. In addition, no PrPCWD was detected in skeletal muscle of any of the deer.

Conclusions: Our data suggest that expression of H95-PrPC limits peripheral accumulation of PrPCWD as detected by immunohistochemistry. Conversely, infected S96/wt and wt/wt deer presented with similar PrPCWD peripheral distribution at terminal stage of disease, suggesting that the S96-PrPC allele, although delaying CWD progression, does not completely limit the peripheral accumulation of the infectious agent.

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The significantly longer incubation periods observed in deer with H95-PRNP alleles may not impact secretion of CWD (i.e., less CWD secreted over longer time periods). The emergence of new CWD strains could implicate a zoonotic potential [20]. 

Keywords: Prions, Prion diseases, Chronic wasting disease, CWD, PrPCWD, Peripheral tissues, Polymorphisms, Deer


***> Selective Breeding

***> less susceptible to CWD infection, present prolonged survival times...

this is very disturbing. with all the hype about selective breeding with different alleles, and presenting longer survival times with cwd, this would only allow the spreading of the cwd tse prion to last longer in the given environment imo., and as such has been stated in scientific literature...terry


With cervids, however, resistance based on the PRNP allele alone is not absolute, and is better characterized as a delayed progression [18,25]


Volume 23, Number 9—September 2017 Research Letter

Chronic Wasting Disease Prion Strain Emergence and Host Range Expansion

Allen Herbst1, Camilo Duque Velásquez1, Elizabeth Triscott, Judd M. Aiken, and Debbie McKenzieComments to Author Author affiliations: University of Alberta, Edmonton, Alberta, Canada

Abstract

Human and mouse prion proteins share a structural motif that regulates resistance to common chronic wasting disease (CWD) prion strains. Successful transmission of an emergent strain of CWD prion, H95+, into mice resulted in infection. Thus, emergent CWD prion strains may have higher zoonotic potential than common strains.


P-145 Estimating chronic wasting disease resistance in cervids using real time quaking- induced conversion

Nicholas J Haley1, Rachel Rielinqer2, Kristen A Davenport3, W. David Walter4, Katherine I O'Rourke5, Gordon Mitchell6, Juergen A Richt2 1 Department of Microbiology and Immunology, Midwestern University, United States; 2Department of Diagnostic Medicine and Pathobiology, Kansas State University; 3Prion Research Center; Colorado State University; 4U.S. Geological Survey, Pennsylvania Cooperative Fish and Wildlife Research Unit; 5Agricultural Research Service, United States Department of Agriculture; 6Canadian Food Inspection Agency, National and OlE Reference Laboratory for Scrapie and CWD

In mammalian species, the susceptibility to prion diseases is affected, in part, by the sequence of the host's prion protein (PrP). In sheep, a gradation from scrapie susceptible to resistant has been established both in vivo and in vitro based on the amino acids present at PrP positions 136, 154, and 171, which has led to global breeding programs to reduce the prevalence of scrapie in domestic sheep. In cervids, resistance is commonly characterized as a delayed progression of chronic wasting disease (CWD); at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified. To model the susceptibility of various naturally-occurring and hypothetical cervid PrP alleles in vitro, we compared the amplification rates and efficiency of various CWD isolates in recombinant PrPC using real time quaking-induced conversion. We hypothesized that amplification metrics of these isolates in cervid PrP substrates would correlate to in vivo susceptibility - allowing susceptibility prediction for alleles found at 10 frequency in nature, and that there would be an additive effect of multiple resistant codons in hypothetical alleles. Our studies demonstrate that in vitro amplification metrics predict in vivo susceptibility, and that alleles with multiple codons, each influencing resistance independently, do not necessarily contribute additively to resistance. Importantly, we found that the white-tailed deer 226K substrate exhibited the slowest amplification rate among those evaluated, suggesting that further investigation of this allele and its resistance in vivo are warranted to determine if absolute resistance to CWD is possible.

***at present, no cervid PrP allele conferring absolute resistance to prion infection has been identified.

PRION 2016 CONFERENCE TOKYO


''There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.'' c) The commonest form of CJD occurs as a sporadic disease, the cause of which is unknown, although genetic factors (particularly the codon 129 polymorphism in the prion protein gene (PRNP)) influence disease susceptibility. The familial forms of human TSEs (see Box 1) appear to have a solely genetic origin and are closely associated with mutations or insertions in the PRNP gene. Most, but not all, of the familial forms of human TSEs have been transmitted experimentally to animals. There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.


''There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.''

c) The commonest form of CJD occurs as a sporadic disease, the cause of which is unknown, although genetic factors (particularly the codon 129 polymorphism in the prion protein gene (PRNP)) influence disease susceptibility. The familial forms of human TSEs (see Box 1) appear to have a solely genetic origin and are closely associated with mutations or insertions in the PRNP gene. Most, but not all, of the familial forms of human TSEs have been transmitted experimentally to animals. There are no known familial or genetic TSEs of animals, although polymorphisms in the PRNP gene of some species (sheep for example) may influence the length of the incubation period and occurrence of disease.


Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: Complement component C1q and Prnp polymorphisms§

Julie A. Blanchong a, *, Dennis M. Heisey b , Kim T. Scribner c , Scot V. Libants d , Chad Johnson e , Judd M. Aiken e , Julia A. Langenberg f , Michael D. Samuel g

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Identifying the genetic basis for heterogeneity in disease susceptibility or progression can improve our understanding of individual variation in disease susceptibility in both free-ranging and captive populations. What this individual variation in disease susceptibility means for the trajectory of disease in a population, however, is not straightforward. For example, the greater, but not complete, resistance to CWD in deer with at least one Serine (S) at amino acid 96 of the Prnp gene appears to be associated with slower progression of disease (e.g., Johnson et al., 2006; Keane et al., 2008a). If slower disease progression results in longer-lived, infected deer with longer periods of infectiousness, resistance may lead to increased disease transmission rates, higher prion concentrations in the environment, and increased prevalence, as has been observed in some captive deer herds (Miller et al., 2006; Keane et al., 2008a). Alternatively, if the slower progression of disease in resistant deer is not associated with longer periods of infectiousness, but might instead indicate a higher dose of PrPCWD is required for infection, transmission rates in the population could decline especially if, as in Wisconsin, deer suffer high rates of mortality from other sources (e.g., hunting). Clearly, determining the relationship between genetic susceptibility to infection, dose requirements, disease progression, and the period of PrPCWD infectiousness are key components for understanding the consequences of CWD to free-ranging populations.








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. ... 



Sunday, January 10, 2021 

APHIS Concurrence With OIE Risk Designation for Bovine Spongiform Encephalopathy [Docket No. APHIS-2018-0087] Singeltary Submission June 17, 2019


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




Why didn’t USDA continue to test animals at the enhanced surveillance level? 

USDA's 2004-2006 enhanced surveillance program was initiated in response to the first detection of BSE in the United States and was designed to detect the overall prevalence of the disease in this country. This required a very intensive effort and it allowed us to estimate extremely low prevalence levels of disease. Once that prevalence level was determined, USDA modified its testing levels to monitor any changes in the level of disease. Our current testing of approximately 25,000 targeted animals a year allows USDA to detect BSE at the very low level of less than 1 case per million adult cattle, assess any change in the BSE status of U.S. cattle, and identify any rise in BSE prevalence in this country.

WEDNESDAY, MARCH 16, 2022 

SHEEP BY-PRODUCTS AND WHAT ABOUT Scrapie TSE PrP and Potential Zoonosis? 


RIDAY, OCTOBER 1, 2021 

Bovine Spongiform Encephalopathy BSE TSE Prion Origin, USA, what if?


SATURDAY, DECEMBER 04, 2021

Final rule on the Importation of Sheep, Goats, and Certain Other Ruminants (APHIS-2009-0095) Scrapie, BSE, CWD, TSE Prion

This is an incredibly bad idea, based on trade, not science, imo...terry


WEDNESDAY, DECEMBER 8, 2021 

Importation of Sheep, Goats, and Certain Other Ruminants AGENCY: Animal APHIA, USDA, FINAL RULE [Docket No. APHIS–2009–0095] RIN 0579–AD10


re-Study contemplates predators' role in reducing chronic wasting disease


***> 10. Movement of other animals (working dogs, scavengers, predators). 

***> Faeces of predators (in North America e.g. coyotes or pumas) can serve as a vehicle for prions contributing to the spread of the infectious agent in the environment. Miller et al. (2008) cohort B N Nichols et al. (2015) other

SNIP...SEE FULL TEXT;


CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans)

snip...

The results of this bioassay indicate that infectious CWD prions are able to be passed in the feces of coyotes fed infected elk brain homogenate for at least 3 DPI, making them a potential vector for CWD prion transport and contamination within the environment. 


no tse prp in canine...don't bet on it...


*** DEFRA TO SINGELTARY ON HOUND STUDY AND BSE 2001 *** 

*** DEFRA TO SINGELTARY ON HOUND STUDY AND BSE 2001 ***
DEFRA Department for Environment, Food & Rural Affairs
Area 307, London, SW1P 4PQ Telephone: 0207 904 6000 Direct line: 0207 904 6287 E-mail: h.mcdonagh.defra.gsi.gov.uk
GTN: FAX:
Mr T S Singeltary P.O. Box 42 Bacliff Texas USA 77518
21 November 2001
Dear Mr Singeltary
TSE IN HOUNDS
Thank you for e-mail regarding the hounds survey. I am sorry for the long delay in responding.
As you note, the hound survey remains unpublished. However the Spongiform Encephalopathy Advisory Committee (SEAC), the UK Government's independent Advisory Committee on all aspects related to BSE-like disease, gave the hound study detailed consideration at their meeting in January 1994. As a summary of this meeting published in the BSE inquiry noted, the Committee were clearly concerned about the work that had been carried out, concluding that there had clearly been problems with it, particularly the control on the histology, and that it was more or less inconclusive. However was agreed that there should be a re-evaluation of the pathological material in the study.
Later, at their meeting in June 95, The Committee re-evaluated the hound study to see if any useful results could be gained from it. The Chairman concluded that there were varying opinions within the Committee on further work. It did not suggest any further transmission studies and thought that the lack of clinical data was a major weakness.
Overall, it is clear that SEAC had major concerns about the survey as conducted. As a result it is likely that the authors felt that it would not stand up to r~eer review and hence it was never published. As noted above, and in the detailed minutes of the SEAC meeting in June 95, SEAC considered whether additional work should be performed to examine dogs for evidence of TSE infection. Although the Committee had mixed views about the merits of conducting further work, the Chairman noted that when the Southwood Committee made their recommendation to complete an assessment of possible spongiform disease in dogs, no TSEs had been identified in other species and hence dogs were perceived as a high risk population and worthy of study. However subsequent to the original recommendation, made in 1990, a number of other species had been identified with TSE ( e.g. cats) so a study in hounds was less
critical. For more details see- http://www.bseinquiry.gov.uk/files/yb/1995/06/21005001.pdf
As this study remains unpublished, my understanding is that the ownership of the data essentially remains with the original researchers. Thus unfortunately, I am unable to help with your request to supply information on the hound survey directly. My only suggestion is that you contact one of the researchers originally involved in the project, such as Gerald Wells. He can be contacted at the following address.
Dr Gerald Wells, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, KT 15 3NB, UK
You may also wish to be aware that since November 1994 all suspected cases of spongiform encephalopathy in animals and poultry were made notifiable. Hence since that date there has been a requirement for vets to report any suspect SE in dogs for further investigation. To date there has never been positive identification of a TSE in a dog.
I hope this is helpful
Yours sincerely 4
HUGH MCDONAGH BSE CORRESPONDENCE SECTION
======================================
HOUND SURVEY
I am sorry, but I really could have been a co-signatory of Gerald's minute.
I do NOT think that we can justify devoting any resources to this study, especially as larger and more important projects such as the pathogenesis study will be quite demanding.
If there is a POLITICAL need to continue with the examination of hound brains then it should be passed entirely to the VI Service.
J W WILESMITH Epidemiology Unit 18 October 1991
Mr. R Bradley
cc: Mr. G A H Wells
3.3. Mr R J Higgins in conjunction with Mr G A Wells and Mr A C Scott would by the end of the year, indentify the three brains that were from the ''POSITIVE'' end of the lesion spectrum.
DEFRA Department for Environment, Food & Rural Affairs Area 307, London, SW1P 4PQ Telephone: 0207 904 6000 Direct line: 0207 904 6287 E-mail: h.mcdonagh.defra.gsi.gov.uk GTN: FAX: Mr T S Singeltary P.O. Box Bacliff Texas USA 77518 21 

November 2001 

Dear Mr Singeltary 

TSE IN HOUNDS 


Monday, March 26, 2012 

CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE 


*** DEFRA TO SINGELTARY ON HOUND STUDY AND BSE 2001 *** 

DEFRA Department for Environment, Food & Rural Affairs Area 307, London, SW1P 4PQ Telephone: 0207 904 6000 Direct line: 0207 904 6287 E-mail: h.mcdonagh.defra.gsi.gov.uk GTN: FAX: 

Mr T S Singeltary P.O. Box  Bacliff Texas USA 77518 21 

November 2001 

Dear Mr Singeltary 

TSE IN HOUNDS 


TSE in dogs have not been documented simply because OF THE ONLY STUDY, those brain tissue samples were screwed up too. see my investigation of this here, and to follow, later follow up, a letter from defra, AND SEE SUSPICIOUS BRAIN TISSUE SAF's. ...TSS 


76 pages on hound study; 

snip... 


Monday, March 26, 2012 

CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE 


TSE & HOUNDS GAH WELLS (very important statement here...TSS) 

HOUND STUDY 

AS implied in the Inset 25 we must not _ASSUME_ that transmission of BSE to other species will invariably present pathology typical of a scrapie-like disease. 

snip... 


MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019


THURSDAY, MARCH 31, 2022 

EFSA ONE Conference 2022 Chronic Wasting Disease CWD TSE PrP of Cervid and Zoonosis Zoonotic Transmission Singeltary Submission


TUESDAY, MARCH 29, 2022 

OIE Agent causing chronic wasting disease (CWD) TSE Prion of Cervid


THURSDAY, MARCH 24, 2022 

EID Journal Volume 28, Number 4—April 2022

Increased Attack Rates and Decreased Incubation Periods in Raccoons with Chronic Wasting Disease Passaged through Meadow Voles



Friday, March 11, 2022 

Prevalence of Surgical Procedures at Symptomatic Onset of Prion Disease


THURSDAY, APRIL 21, 2022 
 
Transmission of Cervid Prions to Humanized Mice Demonstrates the Zoonotic Potential of CWD
 

FRIDAY, JANUARY 31, 2020 
 
CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307
 
 
Thursday, October 28, 2021 
 
Chronic Wasting Disease (CWD) TSE Prion Zoonosis, friendly fire, iatrogenic transmission, blood products, sporadic CJD, what if?
 
 
Thursday, July 29, 2021 
 
TSE PRION OCCUPATIONAL EXPOSURE VIA ANIMAL OR HUMAN, iatrogenic transmission, nvCJD or sCJD, what if? 
 

Terry S. Singeltary Sr.

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