News & Features

White-tailed Deer in Libby Tests Positive for Chronic Wasting Disease

Report marks first case of disease west of the Continental Divide in Montana

A white-tailed doe killed in Libby has tested positive for chronic wasting disease, marking the first time the disease has been detected west of the Continental Divide in Montana.

Officials with Montana Fish, Wildlife and Parks (FWP) killed the doe after residents reported seeing a very emaciated and sick-looking deer. This week, initial test results came back positive for chronic wasting disease (CWD). Results of a second confirmation test are expected early next week.

In accordance with FWP’s CWD response plan, an incident command team has been assembled to respond to the detection. The incident command team will define an Initial Response Area (IRA) around where the infected animal was collected, which occurred inside Libby city limits. This will include an area within a roughly 10-mile radius of the collection site. The IRA defines the area within which the disease prevalence and distribution will be determined.

In addition, FWP will collect samples from road-killed deer in hunting districts 100, 101, 103 and 104.

Anyone in the Libby area who sees a deer that appears to be sick should call (406) 291-6539 and leave a message with a name, number, the location of the animal, and the time it was spotted.

CWD is a progressive, fatal disease affecting the nervous system of mule deer, white-tailed deer, elk and moose. It is part of a group of diseases called Transmissible Spongiform Encephalopathies (TSEs). TSEs are caused by infectious, mis-folded prion proteins, which cause normal prion proteins throughout a healthy animal’s body to mis-fold, resulting in organ damage and eventual death.

CWD is a slow-moving disease. However, left unmanaged, it could result in long-term population declines within affected herds. All the states and provinces that border Montana, other than Idaho and British Columbia, have found CWD in their wild cervids, or members of the deer family.

CWD was first found in wild deer in Montana in October 2017. To date, CWD has been detected in Carbon, Liberty, Hill, Blaine, Phillips, Valley, Daniels, Sheridan and now Lincoln counties.

To prevent the spread of CWD within Montana, FWP establishes CWD Management Zones in areas where CWD has been found. Whole carcass, whole head or spinal column from any deer, elk, or moose harvested cannot be removed from these zones unless the animal has tested negative for CWD.

For more information about CWD in Montana, visit fwp.mt.gov and click on Chronic Wasting Disease Management.