Colorado wildlife expert report on state of CWD With the first five-year period of mandatory chronic wasting disease (CWD) testing in the books, Colorado wildlife experts shared what they’ve learned about the prevalence of the disease within the state. Between 2017 and 2021, Colorado Parks and Wildlife (CPW) collected CWD samples from deer during hunting season in an effort to determine infection rates and future strategies for disease management, according to The Fort Morgan Times.