These diseases are always fatal. After the animal dies, tissue samples show a series of microscopic holes in and around its brain cells. You can't kill CWD and related diseases by cooking the animal's meat. Most disinfectants don't kill these disease agents, and they can exist in the soil for years.
Prions can even remain infectious on correctly sterilized surgical instruments.
In fact, the rates of transmission are highest in areas where animals have the most opportunity for contact. Outbreaks of the disease have also been found among farmed elk in Colorado and Wyoming, and in other Western states, forcing the destruction of herds and the quarantining of farms. The disease was traced to an animal exported to Canada from South Dakota. It is scientifically established that infected Western elk can transmit CWD to native New York deer putting the entire herd at risk.