HOT SPRINGS — Chronic wasting disease (CWD) has been found in an elk in Wind Cave National Park, superintendent Linda L. Stoll announced Monday.
Park staff recently discovered a 5-year-old elk exhibiting symptoms of the contagious brain disease. The elk was killed and brain tissue samples were analyzed at the Colorado State University Diagnostic Lab in Fort Collins, which confirmed the diagnosis.
It was the second case of CWD in a free-ranging big-game animal and the second elk in the Southern Hills to contract the disease this year.
A deer shot by a hunter in near Oral last year tested positive for CWD, and state game officials have continued testing deer and elk for CWD.
Last summer an elk in a private herd west of Highway 79 near Fairburn died of CWD.
Six captive elk herds, including some in the Black Hills area, became infected with CWD beginning in 1997. One of the infected herds was adjacent to Wind Cave National Park’s southern boundary.
It is unknown where the park elk became infected with CWD.
Wind Cave National Park officials are consulting with national and state wildlife experts concerning the outbreak in the park, according to a news release.
Public health officials have found no scientific evidence that CWD can be transmitted to humans, or to animals other than deer and elk. However, research on possible links is continuing.
CWD is a fatal condition affecting a game animal’s brain and central nervous system.
Infected animals show progressive loss of weight and body condition, behavioral changes, excessive salivation, increased drinking and urination, depression, loss of muscle control and eventual death.
Related to mad cow disease, CWD is believed to affect only deer and elk, and it is thought to be caused by an abnormal protein called a prion that attacks the animal’s brain tissue.
How the disease is transmitted is unknown, although direct contact between infected and non-infected animals via saliva, urine, and feces is considered the most likely route of transmission, according to the park news release.
The disease can not be diagnosed by observation of physical symptoms because many big-game diseases affect animals in similar ways, according to the state Game, Fish & Parks Department.
The origin and transmission of this disease among deer and elk is not well understood.
Test tube experiments have shown that human proteins are as susceptible to chronic wasting disease as to mad cow disease, according to a June story in the Rocky Mountain News.
The elk found in Wind Cave National Park was believed to be part of the Gobbler Knob sub-herd, located in the southern part of the park.
Last summer, the park received $279,000 to conduct a multi-year study to learn about deer movement patterns, density levels within the park, and to test for CWD. This study, scheduled to begin in February, will be conducted in cooperation with South Dakota State University and GF&P.
“We are concerned about the threat this disease poses to area deer and elk herds, and we’ll be coordinating with the state of South Dakota to use our upcoming study to learn more about the occurrence of this disease,” Stoll said.
This was the 10th elk or deer from the park tested since March 1998.
All previous tissue samples returned negative for CWD. Along with expanding the type of surveillance that found the diseased animal, park officials intend to increase the number of deer involved in the research beginning this winter, Stoll said. Information collected in the park will then be combined with data gathered by GF&P to determine the need for further action.
GF&P is collecting deer heads from participating hunters this fall and sending tissue samples to be tested for CWD.