The use of feeders may be one of the reasons we see the spreading. From what I've read "CWD proteins (prions) likely spread between animals through body fluids like feces, saliva, blood, or urine, either through direct contact or indirectly through environmental contamination of soil, food or water "I wish there was a vaccine. If they could develop one , it wouldn't be that difficult to administer with feeders. They even drop rabies medicine from airplanes to raccoons and skunks.
Feeders tend to conjugate several animals to a central location allowing healthy deer to associate with infected animals.