FORT PIERRE — The South Dakota Game, Fish and Parks Department says chronic wasting disease has been confirmed in Stanley County. Chronic wasting disease is a fatal brain disease that impacts deer, elk and moose and is caused by an abnormal protein called a prion. The confirmation in Stanley County was made in an adult female mule deer. Stanley County is now classified as a C-W-D endemic area and joins 17 other central and western South Dakota counties with confirmed cases including, Sully, Haakon, Jackson, Tripp Mellette and Lyman. Most harvested animals with chronic wasting disease will appear health and show no outward signs of being sick. In later stages of infection, animals may show progressive weight loss and body condition, behavioral changes, excessive salivation, loss of muscle control and eventual death. The Game, Fish and Parks Commission has imposed modified carcass transportation and disposal regulations for all of South Dakota with the goal of reducing the artificial spread of the disease.