Chronic wasting disease (CWD) is a horizontally transmitted transmissible spongiform encephalopathy (TSE) of deer and elk recently emergent in the Western United States. Although there is no evidence that this disease can be transmitted to humans, caution is warranted due to the precedent of Bovine Spongiform Encephalopathy (BSE, aka """"""""Mad Cow Disease"""""""") transmitting to humans and giving rise to a new TSE (variant Creutzfeldt-Jakob disease, vCJD). This project has the objective of understanding the mechanisms by which CWD is transmitted in the wild, the factors that affect its spread to other species, and approaches for detecting, and thus controlling human exposure to, infected animals. Additional objectives include: ? Assess the potential infectivity and thus transmissibility of the CWD prion agent in blood, muscle, excreta, and saliva in the native deer species. ? Develop cervid PrPc transgenic mice to study CWD prion infectivity, transmission, host range, pathogenesis, and therapeutics. ? Evaluate the potential for inter-species transmission and pathogenesis of CWD. ? Evaluate a PrP peptide immunization to prevent CWD infection in deer. ? Develop animal models, inocula, facilities, and assays that will allow the investigative team to quickly respond to issues relevant to the natural emergence of TSEs. This project will develop a repository of tissues, body fluids, and inocula from all species which develop TSE following CWD inoculation and make CWD-specific reagents and assay protocols available to other investigators. Tissues and reagents will be cataloged and made available to other scientists working in the TSE field.