Chronic Wasting Disease or CWD is a neurological disease that affects animals such as deer, mule deer, elk, and moose (cervids). Once an animal is infected, there is no cure, and it is 100% fatal. It can take several years from the time an animal is initially infected until they start showing symptoms such as weight loss, hair loss, poor co-ordination, and erratic behaviour before it inevitably dies. Iga Stasiak is a wildlife health specialist with the Saskatchewan Ministry of Environment, who’s tracked this growing problem over the last few decades.
“We saw our first case in 1997 in the Regina area on a captive game farm and a few years later the disease was detected in wild mule deer just north of Lloydminster. Since then, we have seen the disease spread fairly widely within the province and we're now at a point where we are seeing some population impacts and given the high rates we're seeing in much of the province, it is problematic to our wild cervid population.”
CWD is a prion or an infectious protein that inhabits the brain of a cervid (deer, moose) which spreads and then causes deterioration of the brain tissue. Along the same lines as BWE (mad-cow disease) or Creutzfeldt-Jakob disease in humans, it essentially erodes the brain away and causes the animal to experience essentially dementia. They forget to eat, forget where they are, forget survival skills and wander aimlessly until they eventually die. Stasiak talks about how it spreads, and just how dangerous this disease is.
“It's a problematic disease and that there's no treatment or cure, so once animals are infected, they do not recover. It's always fatal. On average, mortality within two years in deer and it spreads relatively easily. It's spread through bodily fluids such as urine, feces, and saliva. It can be spread through direct contact between animals and also through environmental contamination.”
While CWD has been identified as early as the 1960’s in Colorado and extensively studied for the last 50 years, there are still many myths and misconceptions surrounding the disease, such as the transmission to humans or other animals. Stasiak hopes to clear up some of the confusion.
“CWD is not known to be transmissible to species other than members of the cervid family under natural conditions. However, there have been experimental studies where they tried to infect different species of livestock, rodents, cats and some of those experimental studies, they have shown some level of transmission to those animals. However, a lot of those studies, they're directly infecting the brain of those animals and that's not how animals would naturally be infected. So far, there have been no known cases in humans, but there have been recommendations from health authorities just to utilize caution and avoid consuming animals that are known to be infected.”
If you notice a cervid that you believe is infected with CWD, there are carcass disposal sites throughout the province to dispose. For more information surrounding CWD, proper disposal techniques, environmental procedures and testing results, visit the Government of Saskatchewan’s website.