AVMA.org: CWD prions are amazing for their ability to spread as a virus would, through saliva, urine, and feces as well as contaminated environments, according to Dr. Edward A. Hoover, a professor and infectious disease researcher at Colorado State University. The Hoover laboratory’s CWD research includes assay and vaccine development, although Dr. Hoover said the latter is a difficult prospect because of the lack of a known immune response to prion diseases.

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