Yellowstone National Park officials have announced the discovery of chronic wasting disease (CWD) in an adult mule deer buck, marking the first confirmed case of the fatal brain disease in the park. The deer carcass was found near Yellowstone Lake, having been captured in Cody, Wyoming, in March as part of a population study. The animal was fitted with a GPS collar, which indicated that it died in mid-October. Multiple diagnostic tests were conducted, confirming the presence of CWD in the deer.

Chronic wasting disease, also known as “zombie” deer disease, affects deer, elk, reindeer, and moose. It is a rare neurodegenerative disorder caused by prion proteins and primarily impacts the central nervous system. Infected animals may exhibit symptoms such as weight loss, reluctance to move, excessive salivation, increased drinking and urination, drooping ears, and eventual death. However, the majority of CWD-positive animals may appear normal and healthy, according to the Wyoming Game and Fish Department.

The disease is transmitted through bodily fluids and waste, including saliva, urine, feces, and carcasses. Contamination of feed or pasture with prions can also lead to infection. Once established, there is currently no effective strategy to eradicate CWD, making prevention and monitoring crucial. The National Park Service plans to collaborate with other agencies to identify high-risk areas for disease spread, increase monitoring efforts, and conduct sample testing.

While there have been no reported cases of CWD infection in humans, concerns remain about the potential risk. Some studies suggest that monkeys exposed to infected animal meat or bodily fluids may be at risk. The World Health Organization has advised against the consumption of prion-infected animals since 1997. Further research is being conducted to determine if certain individuals may be more susceptible to developing prion diseases like CWD.

The recent confirmation of CWD in Yellowstone National Park raises uncertainty about the long-term impact on the deer, elk, and moose populations in the area. The disease has been spreading across Wyoming since the mid-1980s and is now prevalent throughout most of the state. It is estimated that 10-15% of the mule deer near Cody, known to migrate to the southeastern section of Yellowstone in the summer, are affected by CWD. Currently, no treatments or vaccines exist for the disease, emphasizing the importance of continued monitoring and prevention efforts.