(WFXR) — All deer harvested by hunters in Montgomery, Pulaski, and Floyd counties must be tested for Chronic Wasting Disease (CWD), according to the Virginia Department of Wildlife Resources (DWR).

This decision comes as the start of firearms season for deer across the Commonwealth on Saturday, Nov. 13. Virginia offers some of the best deer hunting in the eastern United States.

On the DWR Facebook page, the organization states that all deer — except for fawn — must be tested. The testing will be done at sampling stations set up by the DWR in those Montgomery, Pulaski, and Floyd counties, as well as several others in Virginia.

Wildlife managers are testing the deer to keep CWD from spreading and negatively affecting Virginia’s deer population.

The disease is a neurological disorder caused by transmissible protein particles called prions. It causes deer to lose coordination and bodily functions until they die. The DWR states that these prions can be passed between deer through saliva, feces, urine, and through water or soil contaminated with prions.

The disease has been found in deer harvested from Montgomery County during the 2020-21 deer season. The DWR says that the deer was a 2.5-year-old male deer.