Colorado Parks and Wildlife will conduct mandatory chronic wasting disease testing during the 2020 hunting season in specific game management units as part of efforts to control spread of the disease with its Colorado Chronic Wasting Disease Response Plan.

Beginning in late September, CPW will send letters to Colorado rifle season deer (buck and doe) hunters who have been selected for mandatory testing. Eighty-nine GMUs, the majority on the Western Slope, are included in the 2020 mandatory sample. Mandatory and voluntary sampling is critical for data collection on this disease that impacts the long-term health of herds. 

For a complete list of this year’s mandatory GMUs, see pages 20-34 of the 2020 Colorado Big Game Brochure. 

Chronic wasting disease is a prion disease that affects Colorado’s deer, elk and moose. The disease course generally lasts two to three years and is always fatal. 

Although there has been no evidence that the disease has yet been transmitted to humans, the Centers for Disease Control, along with CPW, recommends that hunters not eat the meat of a CWD-infected animal.

Other regulations related to CWD samples and CWD-positive test results

CPW does not offer a replacement license or refund license fees to hunters who harvest a CWD-positive animal. This is in line with other states’ CWD regulations and helps ensure the testing program maintains adequate funding.

Hunters whose deer tests positive for CWD will get a letter mailed to them by CPW explaining what is known about CWD, disposal recommendations and public health information. 

It will also provide links to online sources for additional information. In addition to this letter, each hunter with a CWD-positive animal will be notified once by phone and email.

Updated information on CWD and the 2020 mandatory sample will be posted on CPW’s website at