Chronic Wasting Disease

"I would say this question [whether the wasting disease afflicting deer could infect humans] was answered with 'yes'."

"The more we did, the more we could confirm the macaques [laboratory experimental monkeys] were infected."

Hermann Schaetzl, veterinary scientists, University of Calgary

"It's easy to go down a doomsday scenario but I don't think we're there yet."

"I think it's low-risk."

Dr.Keith Lehman, provincial veterinarian, Alberta  

 

"I was shocked when we first learned of the results. It's absolutely confirmative that this happened — you could give macaques a prion disease through oral consumption of contaminated meat."  

"[For] many people with a spinal cord syndrome, it wouldn't even occur to the treating neurologist that this could be a prion disease. It's going to take some education and alertness to even think of the diagnosis." 

"I hear the alarm bells going off."  

"I would have expected a human case to emerge in the U.S. before Canada. But on the weight of evidence, I think it's not only not impossible, it's kind of expected at this point."

Neil Cashman, prion expert, University of British Columbia 

New research on chronic wasting disease has raised new fears about whether the illness could infect humans. (Radio-Canada)

Decades ago the world was horrified when an outbreak of variant Creutzfeldt-Jakob disease saw people dying horrible deaths in the United Kingdom, linked to the consumption of infected internal organs from cattle finding their way into animal feedlots, butchered animals for human consumption then passing on the disease that causes degenerative brain wasting as a result of proteins called prions that were abnormally shaped. Once infected, deterioration was swift and deadly, a horrendous scenario.

Now, a spread of a fatal wildlife disease in Alberta and Saskatchewan is infecting deer across a wide area of the Canadian Prairies. Research about to be published on Chronic Wasting Disease highlights fears over whether the illness could end up crossing the species barrier and infect humans. A recent report from the Canadian Agri-Food Policy Institute advising the federal government on agriculture policy resulted from a study of Professor Schaetzl's research.

The Institute had concluded that the spread of the disease over the past decade is a dire threat to Western Canada's agriculture, wildlife and food security. Quite apart from, but connected to concerns over transmission to humans. "It's continuing to increase in its spread and the speed of its spread", the Institute's strategy officer, Ted Bilyea, stated.

"The southern range [of caribou] is pretty much the northern range for our survey. If [prions] pass through that, then we have a genuine food security problem for our northern people." Dr.Bilyea is referring to hunters, susceptible to contracting the disease in the closeness of their proximity to infected animals, mostly First Nations hunters. "We don't have any buffer zone. It's not a very pleasant idea, but this is not a very pleasant topic."

 

Chronic Wasting Disease is a prion disease which deer, elk and caribou, in both wild and farmed populations in Canada, the U.S., and more recently in South Korea and Scandinavia are susceptible to; highly contagious between hoofed animals. It is spread through saliva, animal carcasses and fecal matter. Soil and vegetation in areas where infected animals have died can be contaminated with it. The pathogen can survive up to a decade in an area. Data indicates potential transmission to cats, pigs, sheep, cows and rodents.

 

It attacks the nervous system of afflicted animals and its presence is always fatal, the morbid illness is excruciating but fairly swiftly concluded in death. Misshapen prions cause the wasting disease, quite similar to Creutzfeldt-Jakob in humans; the prions are able to persist in the environment and to transfer their disease-causing shape to healthy proteins. 

 

An experiment that was conducted on macaque monkeys -- as the closest animal genetically to humans -- in 2006 by German scientists fed macaques with meat from contaminated animals. With the knowledge that the disease can take years to develop the monkeys were not tested until two years ago with the first tests being ambiguous. It soon enough became clear, however, that the monkeys had developed low-level infections.

 

Dr.Schaetzl had been involved in the confirmatory tests, and although his work is in the process of peer-review before publication it was presented in conferences, subsequently widely discussed among experts in the disease. According to Dr.Cashman of the University of British Columbia, a leading prion expert, his opinion is that people could already be suffering from a human form of chronic wasting disease.

 

Deer and elk farmers are required in Saskatchewan and Alberta to test every animal on their farms that dies, including those that are slaughtered, in an effort to ensure that tainted meat is kept out of the food supply. Although theoretically domesticated cattle could be contaminated by wild animals with the disease, no cases of this occurring have yet been recognized.

Male elk during the late autumn season in the backcountry of British Columbia. Mount Assiniboine Provincial Park. Photo by Matthew James Ferguson /Getty Image