A new form of TSE (transmissible spongiform encephalopathy) that is becoming a main concern in the United States is Chronic Wasting Disease, or CWD, which is becoming more prevalent in wild game such as deer, elk, and moose throughout the US.
The disease is related to BSE, or “Mad Cow” Disease, and therefore concern of it being transmitted to humans through the consumption of wild game is growing as more and more deer and elk are found to be infected with the prion-caused disease.
Deer and elk infected with CWD suffer loss of body condition and control, behavioral abnormalities and eventually death. While there have been no confirmed cases of CWD among humans so far, the fact that the disease has spread from endemic areas of northeastern Colorado, southeastern Wyoming and southwestern Nebraska to numerous places across North America is a source of concern for wildlife managers. (Map of CWD cases in wild deer and elk throughout the USA)
The origin of CWD is unknown, mainly because it occurs in wild game that are not closely monitored for infectious diseases. One theory suggests that CWD is derived from scrapie in sheep.
Also unknown among experts is the method by which CWD is transmitted from deer to deer. Theories suggest it may be passed through contact with feces, urine, or saliva but another theory suggests maternal transmission from mother to fetus.
Hopefully scientists can figure out exactly what causes the disease and how it is transmitted amongst wild game in case the disease does become transmissible to humans in the years to come.