SIOUX FALLS, S.D. – Two deer found dead at Wind Cave National Park have tested positive for chronic wasting disease.

Lymph-node samples submitted to the Colorado State University Diagnostic Lab in Fort Collins confirmed the diagnoses, according to a news release from park headquarters.

Since early July, the carcasses of three female mule deer have been found in or near the park. The third carcass was too badly decomposed to be tested.

The finding was expected and does not mean the disease is becoming more prevalent, park officials said. But it could require reducing deer numbers in western South Dakota.

The two dead deer were part of a study of 40 deer fitted with radio collars in February to determine the rate of infection in the park, which is located in the Black Hills. The results are a product of increased efforts to find the disease.

“Prior to that, we were just doing surveys of animals that we might see that were ill or sickly,” said park spokesman Tom Farrell.

Nine other deer have tested positive for chronic wasting disease in the state since July 2002. One elk has tested positive since the disease first struck free-ranging animals in 2001.

State veterinarian Sam Holland said it may soon be necessary to cut deer numbers, both inside and outside the park.

Current plans by the state Department of Game, Fish and Parks calls for killing deer once chronic wasting disease infections reach 3 percent of the animals tested. But Holland said deer are already numerous enough to start harvesting them inside the park and increasing the number of hunting permits.

Holland also agreed that the increase in positive tests is an expected byproduct of increased testing.

Chronic wasting disease is a contagious, fatal brain disorder that affects elk and deer. The disease is in the same category of brain disorders as mad cow disease. But unlike mad cow disease, there is no proven link between chronic wasting disease and a fatal human brain disorder called Creutzfeldt-Jacob Disease.

Chronic wasting disease is not believed to be contagious to humans or domestic animals. But Farrell said hunters should take reasonable precautions, such as not eating any sick animals and wearing latex gloves when handling carcasses.