A type of prion protein has been found in the brains of affected animals, and is believed to be the cause of the disease. The origin and mode of transmission of CWD is unknown. The estimated incubation period is two to five years. During the nearly two decades of monitoring, public health officials and researchers have not found any evidence that CWD can be naturally transmitted to humans or to animals other than deer and elk. Currently, there is no effective live animal test for this disease.
Definitive diagnosis is based on microscopic examination of the brain.
States that have CWD in wild deer and elk populations are considering reducing herds densities. States that have had CWD in captive elk are attempting to eradicate the disease by depopulating any affected herds and developing importation and monitoring programs. There is continued research to better understand the biology of the disease.