Thumper's Link
The study is The species barriers and public health threat of CWD and BSE prions. Ms. Kristen Davenport, Dr. Davin Henderson, Dr. Candace Mathiason, Dr. Edward
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If this report is accurate its a game changer. I'd check the author's credentials to make sure they're not Fund For Animals it PETA board members.
CWD has been of scientific interest to me for a number of years.
I'll read the paper and comment on it specifically in a couple of days. I have a number of other things going right now. There are a lot of new assays and techniques being developed. I have several virtual friends who do research in the field. I'll see if I can get some comments from them. IMHO, I have always felt that due to the nature of prions that there is a possibility that CWD could pass specie barrier like BSE did in England.
However, there are some known facts that should be considered.
1. Prion disease has been shown to cross the specie barrier both in and out of the laboratory. CWD was originally seen in a research herd of deer in Colorado where the deer were kept in a research lot that had been previously used for the study of scrapie positive sheep...scrapie being a prion disease. The abnormal sheep prions contaminated the ground due from urine and feces from the sheep.
2. Bovine spongiform encepatholopathy (BSE), aka "mad cow" was demonstrated to pass from cattle to human in Great Britain. Studies were shown that the abnormal prions were passed from downer cattle who had the disease to other cattle via feed made from the infected cattle. The prions are not destroyed in the process of rendering--the prions need to be incinerated. This is why there are regulations as to the source of protein supplements in animal feed (there is a whole other issue about this).
In GB, vCJD occurred due to dietary habits of the Britians. Parts of beef that would contain possible high concentrations of the abnormal prions are part of their regular diet where such here is pretty much considered offal and not eaten. Venison, much liked by our hunter class, is not widely eaten. I don't have on hand, but I believe there were several papers years ago that both linked and not linked venison consumption to the occurrence of vCJD. (Ha!)
3. Prion disease has numerous symptoms leading up to the final stages before death. Many of these symptoms can be seen in other neurological diseases which can be seen across the spectrum such as MS, dementia, Alzheimer's, CJD, vCJD,etc. Diagnosis of these are made mostly on the diagnosis of the attending physicians, whose skill at diagnosis varies on skill, experience, and expertise. The only certain diagnosis of CWD (and many of these related diseases) is dependent upon laboratory tests of brain tissue.
Michigan had CWD show in the wild herd two years ago and deer in the quarantine area are tested at DCPAH at MSU and any positive is sent to Ames Iowa for verification...
Testing for animals is much easier than with humans. In today's medicine, an autopsy is a rare event as insurance does not pay for the testing. Only if there is a legal reason or a funded study (or rarely medical interest where cost is picked up by hospital), are autopsies performed. Therefore, a cause of death is usually deemed by doctor's diagnosis--so links might not be seen.
3. The process of infection of CWD appears to be oral and the abnormal prions pass from the gut into the lymphatic system eventually reaching the brain where the disease begins to appear. It is usually seen in older deer. It has long been suggested that one avoid contaminating the muscle (meat) by debone-ing rather than sawing through the bones (marrow can contain prionic material); avoiding spleen, liver, brain; wearing gloves...and perhaps using the same knives only for deer and not other game.
Some of the research I have read indicates that the spread of prionic disease may be dose related. If so, if one hunts in a known CWD area, it is probably wise to wait until test results are known before consumption.
The spread of CWD has a high relationship to cervid farming. CWD has been seen in not only deer, but moose, elk and other cervids. Cervid farming has two major sources of funding...trophy animals/breeding stock for such and scent lures. Knowing that urine and feces are sources of infection, it would seem to be wise not to potentially spread the disease with the use of scent lures--but those products are seen in every hunting display. Remember: there are various tests for CWD that are considered screening. The actual presence of CWD is determined by a specific test done on brain tissue. With screening assays, there is the possibility of false negative or positive results.
One thing is certain: once the CWD prions are deposited in an area, it will remain infected. Research done in Iceland with scrapie positive sheep demonstrated that heat, cold, sun, rain--mother nature's normal route of cleansing--do no inactivate the prions. An area that had scrapie positive sheep was left fallow for a year, the top 10" of soil removed and area chemically treated. Negative tested sheep were reintroduced and scrapie was seen within 6 months.
Putting potentially infected urine on our hunting lands seems a very unwise thing to do.
There are a number of past threads on CWD. I will try to post a links to them in a few days when I get a chance to do a historical search.
I'm not convinced the risk is real.
Over 200 people in Britain and France died from BSE. Without the severe containment practices, the death toll would be off the charts. People would no longer eat beef, knowing it could kill them.
Britain health authorities are currently concerned that Mad Cow is still active in the human population, and that new infections may be spread through the medical blood supply. In other words, more people are likely to die from the previous BSE outbreak.
A little research on the topic leaves little room for doubt as to the seriousness of Mad Cow.
Now IF CWD were to be proven to infect humans, then it will be the end of wild ungulate populations in North America. Health authorities have long been prepared to implement a scorched earth policy. The CDC could order the extirpation of all wild ungulates in known CWD areas. National Game farm associations are quietly in favour of this direction, for they would then be the only source of deer/elk....
Anony Mouse's excellent post missed commenting on another alarming discovery in CWD research. IN laboratory settings, CWD has been found to be uptaken by plants, including agricultural crops such as corn and wheat. Governments and financial institutions worldwide are beginning to prepare for the potential that vast swaths of North America's agricultural lands could become declared unfit for growing food. Export of CWD infected produce would be banned, and it is unlikely local consumption would be desired.
The potential ramifications are mind boggling. Some within the financial community are salivating at the opportunities, trying to figure out when to go short...
It is easy to understand the desire to ignore CWD, the potential devastation if this prion crosses the species barrier into humans is mind blowing....
If recommended practices are followed by sportsman as well as American beef/lamb/etc providers then the "real" risk should be reduced to that of being struck by lightning. A risk i am willing to assume for deer chili all winter!!
I hope someday managing risk will be more politically correct that eliminating it in the minds of American politicians as well as the public.
CWD found in a free ranging deer
(Michigan deer...second case, first in a wild deer)
Would like to comment on the subject of protein supplements in feed and government regulations. Because of results seen in Great Britain where the spread of BSE was identified with protein supplements fed to cattle that came from downer cattle. The prions that cause BSE are not destroyed by the process of producing these protein supplements and so can be passed to healthy animals via contaminated feed.
This fact lead to the government banning downer cattle to be used in providing feed to cattle. However, protein supplements from downer cattle can be used for feed destined to feed other species. In the process of producing protein supplements from downer cattle, infective prions are concentrated.
Here's the kicker...while the government bans proteins supplements for cattle sourced from downer cattle, it does not ban their usage for other species: fowls, swine, fish, etc. These animals
See the hitch?
A little background about prion research:
1. There seems to be a genetic factor WRT susceptibility of prion disease. It has been known for a long time that there are several strains of sheep that have resistance to scrapie. This genetic resistance has been seen in other species' prion disease, and some research has shown that this may also be seen in cervids. I recently read a few papers describing some possible epigenetic factors, too.
2. Infection and coming down with prion diseases was hard to produce in laboratory investigations. Much of the knowledge has come where CWD was introduced by inoculation from brain tissue from CWD positive animals. With greater knowledge, the disease was introduced orally. It appears that infection may be does related...which coincides with increased exposure in cervid farming, where animals are kept in greater density and confined areas than in the wild.
3. There is more than ample evidence that the abnormal prions are passed via urine, feces, and nasal secretions. There have been a number of sensitive assays that can now detect the presence of CWD prions and most states that now have screening programs use a PCR/ELISA assay, but confirmation is still done by the "gold standard" examination of brain tissue at AMES lab. There is a screening test that can be done on live animals, but this test is NOT definitive as it only indicates that the deer tests negative at the time of testing (the negative may be a false negative due to a lower level of prions present than the assay can detect).
4. Due to the nature of prion diseases, there probably will never be a vaccine or cure developed. Deer (and other cervids) are not domestic animals. Domestication of wild animals takes a long period of time and changes the genetic makeup of the species (think about dogs, cats, horses and cattle). Even today, when it comes to cattle/dairy, herd health is something that is monitored on every farm and ranch.
5. The probability of CWD becoming a danger to human health is probably fairly low. First, venison is not part of most people's diets and there has been seen no spike in vCJD or similar diseases among the hunting population. Unlike Great Britain, where the parts of BSE positive animals that contained high prion concentrations were part of the British diet, most consider this to be offal and not eaten. Best recommendations are to avoid eating or coming into contact with neural or lymphatic tissue.
IMHO, dealing with CWD there are two things that can slow the spread or prevent it from appearing in non-infected regions:
1. Tight control/regulation and perhaps elimination of cervid farming. This includes transport and movement of breeding stock.
2. Complete prohibition and banning of all commercial urine based scent lures. If one feels the need to pour urine on the ground, collect and save it from the deer you harvest rather than purchasing a bottle from your favorite hunting outlet.
Anony Mouse's Link
Since few people eat enough venison, the dosage of the abnormal prion is obviously low. Additionally, human hunters have the ability to identify and NOT consume game that is obviously ill, prion dosage again is low. The risk is low, but NOT non-existent. The more CWD is spread and increased in cervid populations, the greater chances of a BSE-like event occurring.
However, it is a fact that prionic disease can be passed between species and hunting activities that promote the spread of the disease will increase (and spread) the incidence of the disease in cervid populations. The link between cervid farming and its spread is a fact. CWD was found in Alberta (the second major locus) and connected to the importation of breeding stock from the Colorado nexus. CWD east of the Mississippi River is also linked to the movement of breeding stock. In WI and MI, the first identified CWD positive animals were found in captive herds.
Occurrence, Transmission, and Zoonotic Potential of Chronic Wasting Disease
Abstract
Chronic wasting disease (CWD) is a fatal, transmissible prion disease that affects captive and free-ranging deer, elk, and moose. Although the zoonotic potential of CWD is considered low, identification of multiple CWD strains and the potential for agent evolution upon serial passage hinders a definitive conclusion. Surveillance for CWD in free-ranging populations has documented a continual geographic spread of the disease throughout North America. CWD prions are shed from clinically and preclinically affected hosts, and CWD transmission is mediated at least in part by the environment, perhaps by soil. Much remains unknown, including the sites and mechanisms of prion uptake in the naive host. There are no therapeutics or effective eradication measures for CWD-endemic populations. Continued surveillance and research of CWD and its effects on cervid ecosystems is vital for controlling the long-term consequences of this emerging disease.
BSE (Mad Cow Disease) is a good example of prions and crossing to humans from bovines. A couple of references:
Mad cow Disease: History & Causes
Prion Diseases and the BSE Crisis (Author is Stanley B. Prusiner--one of the most knowledgeable researchers in the field of prion disease)
Estimate doubled for vCJD carriers in UK
Yes...we should be concerned about CWD and its spread. But for the uninformed, concern is far different than "fear and panic".
There is a new comment on the post "Boone and Crockett - Situational Overview of Chronic Wasting Disease". https://www.ammoland.com/2018/04/boone-and-crockett-situational-overview-of-chronic-wasting-disease/
Author: Terry S. Singeltary Sr. Comment: thank you Boone and Crocket!
APHIS USDA CFIA CWD TSE Prion Herd Certifications Update
FRIDAY, MARCH 30, 2018
Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification Program Standards Singeltary Submission March 30, 2018
Terry S. Singeltary Sr., Bacliff, Texas USA 77518 [email protected] Attachments (1) Docket No. APHIS-2018-0011 Chronic Wasting Disease Herd Certification Program Standards Singeltary View Attachment:View as format pdf
https://www.regulations.gov/document?D=APHIS-2018-0011-0003
https://www.regulations.gov/contentStreamer?documentId=APHIS-2018-0011-0003&attachmentNumber=1&contentType=pdf
https://www.regulations.gov/docketBrowser?rpp=25&so=DESC&sb=commentDueDate&po=0&dct=PS&D=APHIS-2018-0011
http://chronic-wasting-disease.blogspot.com/2018/03/docket-no-aphis-2018-0011-chronic.html
WEDNESDAY, APRIL 04, 2018
Canada Chronic Wasting Disease Voluntary Herd Certification Program Updated
http://chronic-wasting-disease.blogspot.com/2018/04/canada-chronic-wasting-disease.html
''Caribou concerns Alberta’s threatened woodland caribou could also be at risk, said University of Alberta researcher Debbie McKenzie, who is among a group of scientists funded by the Alberta Prion Research Institute. “That’s one thing that we’re very concerned about,” she said, adding at least four CWD strains have been confirmed.''
AT LEAST FOUR STRAINS OF CHRONIC WASTING DISEASE CWD TSE PRION HAS BEEN CONFIRMED!
Province of Alberta
The 29th Legislature Fourth Session Alberta Hansard
Thursday afternoon, March 15, 2018 Day 5 The Honourable Robert E. Wanner, Speaker
Chronic Wasting Disease
Dr. Swann: Mr. Speaker, we learned nothing from the BSE crisis. Mad cow disease, an incurable and rapidly fatal infectious prion disease of the brain, devastated our cattle industry 15 years ago at roughly a cost of $10 billion in lost markets. Conventional wisdom at the time assured us that this could not be transmitted to humans. This proved wrong, and variant CJD cost over 200 human lives.
CWD, chronic wasting disease, is a similar, decades-old prion disease which began in deer and elk farms and is now growing across western Canada in the wild. It is spread easily from body fluids, not only from eating the meat, across the deer family, with weak and inconsistent provincial and federal control measures. Both game farming and wildlife management are provincial issues, but the federal food inspection agency, CFIA, sets the standards for meat safety and just last year relaxed the regulations for controlling this disease.
Paul Glover, the CFIA director, wrote the following: since 2010 CWD has spread and become firmly established in wild cervids in Saskatchewan and Alberta and cannot be eradicated with the tools currently available. End quote. This highlights the failure of cooperation between federal and provincial governments in control measures.
Recent U of C studies on CWD showed that it can be transmitted to experimental monkeys after they eat the flesh of infected deer. This is mobilizing the wildlife and hunting community, especially indigenous communities who depend on wild game. It’s also the agricultural community’s worst nightmare. We know that a significant number of infected deer and elk are consumed without being properly tested.
Dr. Neil Cashman, a noted neurobiologist and prion scientist from UBC, recently said, quote, we appear to be waiting till CWD is found in humans, end quote, before taking serious action on control and elimination of the disease.
This provincial government is negligent. We have learned nothing from . . .
The Speaker: Thank you, hon. member
http://www.assembly.ab.ca/ISYS/LADDAR_files/docs/hansards/han/legislature_29/session_4/20180315_1330_01_han.pdf
MONDAY, APRIL 02, 2018
Canada Liberal MLA David Swann quoted, This provincial government is negligent, spread of CWD reminiscent of the onset of Canada’s mad cow disease crisis
http://chronic-wasting-disease.blogspot.com/2018/04/canada-liberal-mla-david-swann-quoted.html
10. ZOONOTIC, ZOONOSIS, CHRONIC WASTING DISEASE CWD TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY TSE PRION AKA MAD DEER ELK DISEASE IN HUMANS, has it already happened, that should be the question...
''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)
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 TSE?exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
snip...
The tissue distribution of infectivity in CWD?infected 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.
https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2018.5132
zoonosis zoonotic cervid tse prion cwd to humans, preparing for the storm
***An alternative to modeling the species barrier is the cell-free conversion assay which points to CWD as the animal prion disease with the greatest zoonotic potential, after (and very much less than) BSE.116***
https://www.tandfonline.com/doi/pdf/10.4161/pri.29237
***> However, to date, no CWD infections have been reported in people.
key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry
LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
http://www.tandfonline.com/doi/full/10.4161/pri.28124?src=recsys
http://www.tandfonline.com/doi/pdf/10.4161/pri.28124?needAccess=true
https://wwwnc.cdc.gov/eid/article/20/1/13-0858_article
To date there is no direct evidence that CWD has been or can be transmitted from animals to humans.
However, initial findings from a laboratory research project funded by the Alberta Prion Research Institute (APRI) and Alberta Livestock Meat Agency (ALMA), and led by a Canadian Food Inspection Agency (CFIA) scientist indicate that CWD has been transmitted to cynomolgus macaques (the non-human primate species most closely related to humans that may be used in research), through both the intracranial and oral routes of exposure.
Both infected brain and muscle tissues were found to transmit disease.
Health Canada’s Health Products and Food Branch (HPFB) was asked to consider the impact of these findings on the Branch’s current position on CWD in health products and foods.
Summary and Recommendation:
snip...
Health Portfolio partners were recently made aware of initial findings from a research project led by a CFIA scientist that have demonstrated that cynomolgus macaques can be infected via intracranial exposure and oral gavage with CWD infected muscle.
These findings suggest that CWD, under specific experimental conditions, has the potential to cross the human species barrier, including by enteral feeding of CWD infected muscle.
https://www.thetyee.ca/Documents/2017/06/24/Risk-Advisory-Opinion-CWD-2017.pdf
*** WDA 2016 NEW YORK ***
We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions.
In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species.
***We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.
Student Presentations Session 2
The species barriers and public health threat of CWD and BSE prions
Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University
Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein.
These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species.
The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time.
We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations.
We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species.
***We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions. CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD. Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholders
http://www.wda2016.org/uploads/5/8/6/1/58613359/wda_2016_conference_proceedings_low_res.pdf
PRION 2016 TOKYO Zoonotic Potential of CWD Prions:
An Update
Chronic wasting disease (CWD) is a widespread and highly transmissible prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern, but the susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. We reported earlier that peripheral and CNS infections were detected in transgenic mice expressing human PrP129M or PrP129V. Here we will present an update on this project, including evidence for strain dependence and influence of cervid PrP polymorphisms on CWD zoonosis as well as the characteristics of experimental human CWD prions.
PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION 2016 Tokyo Prion 2016
http://prion2016.org/dl/newsletter_03.pdf
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.
http://grantome.com/grant/NIH/R01-NS088604-01A1
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.
http://jvi.asm.org/content/83/18/9608.full
Prions in Skeletal Muscles of Deer with Chronic Wasting Disease
Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.
http://science.sciencemag.org/content/311/5764/1117.long
Terry S. Singeltary Sr.
