The Montana Department of Fish, Wildlife & Parks (FWP) announced May 30 that chronic wasting disease (CWD) was recently found in a white-tailed deer that was killed within the city limits of Libby, Mont., in the state's far northwestern corner.
Officials with FWP collected the doe after residents reported seeing a very emaciated and sick-looking deer.
The agency said initial test results came back positive for CWD this week, and results of a second confirmation test are expected early next week.
According to FWP, this is the first time CWD has been detected in the wild, west of the Continental Divide in Montana.
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. 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 nearby hunting districts.
CWD is a progressive, fatal disease affecting the nervous system of cervids — mule deer, white-tailed deer, elk and moose. It is part of a group of diseases called transmissible spongiform encephalopathies (TSEs), which are caused by infectious, mis-folded prion proteins that 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.
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.