Chronic Wasting Disease...Cured?
Welcome to the first post of The Art of Infection! This week's post is a summary of the recent press conference out of Pennsylvania on the expected "cure" for Chronic Wasting Disease (CWD). I am not alone in my skepticism of a cure for this disease and I will explain that a bit later. For now, let's jump into what CWD is and why it is a bad thing for deer and similar species around the United States for readers unfamiliar with this disease.
CWD is referred to as a prion disease or transmissible spongiform encephalopathy (TSE), always affecting the brain or other parts of the central nervous system. It is a disease that affects species like white-tailed deer, elk, caribou, Sitka deer and moose. A prion is essentially an "evil" protein that causes the normal cellular proteins in the brain to fold in an unnatural way. The result of this folding of normal proteins is brain damage and diseases like CWD, scrapie (in species like sheep), and Creutzfeldt-Jacob disease in humans.
According to the CDC, CWD was first identified in captive deer in Colorado in the 1960's and in wild deer in 1981. This disease was more than likely around long before being identified, however it makes sense why it took some time for the disease to be discovered. The reason for this is because symptoms generally won't show in patients until about a year post-infection. As of January 2019, the CDC reports that CWD has been reported in 251 counties in 24 states, as well as in 2 Canadian provinces. It has also been reported in Norway, Finland and even South Korea.
Diseases like CWD are bad enough to where the United States Department of Health and Human Services has a specific TSE Action Plan to combat these diseases. It is split into the following four parts:
1) Surveillance for human health--Run by the CDC
2) Protection for public health--Run by the FDA
3) Research into TSEs--Run by the NIH
4)Oversight of entire project--Run by the Office of the Secretary of DHHS.
It is believed through many different research studies that the prions for CWD are spread between hosts through contact with bodily fluids. The disease can spread either through direct contact with fluids or indirectly through contamination of soil, food, or water. Symptoms, if actually seen, include distinct weight loss, stumbling, increased salivation, and other neurologic symptoms. The disease does not discriminate with age or sex of the host either.
In February 2019, the United Sportsmen of Pennsylvania hosted a press conference in which they expressed to reporters and the public that along with neurosurgeon Dr. Frank Bastian at Louisiana State University, that they have discovered the "actual cause" for CWD. According to Bastian, it isn't a prion, rather it is a recently discovered species of bacteria called Spiroplasma. Over the next three years, he and the USP hope to raise over $300,000 in order for the next three steps of their research to take place. In the next three years, Bastian and his team will do the following:
1) Create CWD field testing kits for hunters
2) Create an antibiotic vaccine for captive deer and elk
3) Create an oral or nasal vaccine for animals in the wild.
Following this announcement, the Pennsylvania Game Commission released the following statement that they "would like to make clear that decades of research have provided abundant evidence that prions, or misfolded proteins, are the infectious agent of CWD, and this hypothesis is accepted by state agriculture and wildlife agencies across the U.S. While alternative theories exist, they have not been thoroughly researched. Meanwhile, CWD remains a serious threat to Pennsylvania's deer and deer hunting..."
The PGC isn't the only agency that is very skeptical of this research. The Wildlife Society posted a response recently in which they state "wildlife managers and biologist emphasize that decades of scientific research go against it [the research]." There is also concern because as of right now, researchers have been unable to reproduce Bastian's work. When asked about this, Bastian responded "No one has really tried."
So where's my concern in this? Coming from Wisconsin, I have seen agencies attempt to have hunter field tests for use in the state. The Wisconsin Dept. Natural Resources attempted a hunter field kit and only had a return rate of ~20-24% which is very low. I am concerned with the fact that no other researcher has come across something like this in all the years that CWD and other TSE research has been occurring, alongside the fact that Bastians' work is not replicable. I am also skeptical of Bastian's thought process for administering vaccines in the field. There's lots of deer on the landscape, how do we get to them and vaccinate. Not to mention the fact that CWD prions can remain in the soil and on the landscape for well over 2 years.
Obviously we work in a field where research needs to occur in order for advances to be made and in this case, diseases to be cured. However I also feel there are multiple red flags standing tall and proud regarding Bastian and his research. I am curious what your thoughts are. Please leave a comment and let's have a discussion regarding this disease and the recent "cure" for it.
Other interesting articles:
Response to Bastian and the press conference found here
Dr. Bastian's interview with Deer and Deer Hunters here
https://www.sciencedaily.com/releases/2008/08/080811095458.htm
Discussion Questions:
1) What do you think about the change from prion to bacteria after years of research providing strong evidence that prions are the cause?
2) From a wildlife management perspective, is it possible or feasible to try and vaccinate wild populations?
3) Is it wrong for the scientific community (aka wildlife biologists, disease ecologists, etc) to be as skeptical of this? Aren't we looking for a solution to the problem?
Literature Cited:
CWD is referred to as a prion disease or transmissible spongiform encephalopathy (TSE), always affecting the brain or other parts of the central nervous system. It is a disease that affects species like white-tailed deer, elk, caribou, Sitka deer and moose. A prion is essentially an "evil" protein that causes the normal cellular proteins in the brain to fold in an unnatural way. The result of this folding of normal proteins is brain damage and diseases like CWD, scrapie (in species like sheep), and Creutzfeldt-Jacob disease in humans.
According to the CDC, CWD was first identified in captive deer in Colorado in the 1960's and in wild deer in 1981. This disease was more than likely around long before being identified, however it makes sense why it took some time for the disease to be discovered. The reason for this is because symptoms generally won't show in patients until about a year post-infection. As of January 2019, the CDC reports that CWD has been reported in 251 counties in 24 states, as well as in 2 Canadian provinces. It has also been reported in Norway, Finland and even South Korea.
 |
| Photo Courtesy of Bryan Richards, USGS National Wildlife Health Center. Public Domain. |
Diseases like CWD are bad enough to where the United States Department of Health and Human Services has a specific TSE Action Plan to combat these diseases. It is split into the following four parts:
1) Surveillance for human health--Run by the CDC
2) Protection for public health--Run by the FDA
3) Research into TSEs--Run by the NIH
4)Oversight of entire project--Run by the Office of the Secretary of DHHS.
It is believed through many different research studies that the prions for CWD are spread between hosts through contact with bodily fluids. The disease can spread either through direct contact with fluids or indirectly through contamination of soil, food, or water. Symptoms, if actually seen, include distinct weight loss, stumbling, increased salivation, and other neurologic symptoms. The disease does not discriminate with age or sex of the host either.
In February 2019, the United Sportsmen of Pennsylvania hosted a press conference in which they expressed to reporters and the public that along with neurosurgeon Dr. Frank Bastian at Louisiana State University, that they have discovered the "actual cause" for CWD. According to Bastian, it isn't a prion, rather it is a recently discovered species of bacteria called Spiroplasma. Over the next three years, he and the USP hope to raise over $300,000 in order for the next three steps of their research to take place. In the next three years, Bastian and his team will do the following:
1) Create CWD field testing kits for hunters
2) Create an antibiotic vaccine for captive deer and elk
3) Create an oral or nasal vaccine for animals in the wild.
Following this announcement, the Pennsylvania Game Commission released the following statement that they "would like to make clear that decades of research have provided abundant evidence that prions, or misfolded proteins, are the infectious agent of CWD, and this hypothesis is accepted by state agriculture and wildlife agencies across the U.S. While alternative theories exist, they have not been thoroughly researched. Meanwhile, CWD remains a serious threat to Pennsylvania's deer and deer hunting..."
The PGC isn't the only agency that is very skeptical of this research. The Wildlife Society posted a response recently in which they state "wildlife managers and biologist emphasize that decades of scientific research go against it [the research]." There is also concern because as of right now, researchers have been unable to reproduce Bastian's work. When asked about this, Bastian responded "No one has really tried."
So where's my concern in this? Coming from Wisconsin, I have seen agencies attempt to have hunter field tests for use in the state. The Wisconsin Dept. Natural Resources attempted a hunter field kit and only had a return rate of ~20-24% which is very low. I am concerned with the fact that no other researcher has come across something like this in all the years that CWD and other TSE research has been occurring, alongside the fact that Bastians' work is not replicable. I am also skeptical of Bastian's thought process for administering vaccines in the field. There's lots of deer on the landscape, how do we get to them and vaccinate. Not to mention the fact that CWD prions can remain in the soil and on the landscape for well over 2 years.
Obviously we work in a field where research needs to occur in order for advances to be made and in this case, diseases to be cured. However I also feel there are multiple red flags standing tall and proud regarding Bastian and his research. I am curious what your thoughts are. Please leave a comment and let's have a discussion regarding this disease and the recent "cure" for it.
Other interesting articles:
Response to Bastian and the press conference found here
Dr. Bastian's interview with Deer and Deer Hunters here
https://www.sciencedaily.com/releases/2008/08/080811095458.htm
Discussion Questions:
1) What do you think about the change from prion to bacteria after years of research providing strong evidence that prions are the cause?
2) From a wildlife management perspective, is it possible or feasible to try and vaccinate wild populations?
3) Is it wrong for the scientific community (aka wildlife biologists, disease ecologists, etc) to be as skeptical of this? Aren't we looking for a solution to the problem?
Literature Cited:
Centers for Disease Control and Prevention. (2018,
October 9). Prion Diseases. Retrieved from Centers for Disease Control
and Prevention: https://www.cdc.gov/prions/index.html
Centers for Disease Control and Prevention. (2019,
February 25). Chronic Wasting Disease (CWD). Retrieved from Centers for
Disease Control and Prevention: https://www.cdc.gov/prions/cwd/index.html
Eble, J. (2019, February 4). PA sportsmen group
announces partnership for CWD cure, state agencies respond. Retrieved from
FOX 43:
https://fox43.com/2019/02/04/pa-sportsmen-group-announces-partnership-for-cwd-cure-state-agencies-respond/
Frey, D. (2019, March 7). Biologists dispute buzz
over controversial CWD theory. Retrieved from The Wildlife Society:
http://wildlife.org/biologists-dispute-buzz-over-controversial-cwd-theory/?fbclid=IwAR3pmN9xuogAR0yubDJWgzq87lty-Vu5fX-HqkNshgJJ0uGMIV_d9FRQrrI
Gary, T. (2019, February 4). Researchers claim
cure to deadly deer disease, game commission responds. Retrieved from WJAC
TV :
https://wjactv.com/news/local/researchers-claim-cure-to-deadly-deer-disease-game-commission-responds
Race, B., Williams, K., Orru, C. D., Hughson, A. G.,
Lubke, L., & Chesebro, B. (2018). Lack of transmission of chronic wasting
disease to cynomolgus macaques . Journal of Virology, 1-18.
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