A fatal wildlife disease has been detected for the first time in wild populations of white-tailed deer in Pennsylvania.
The Pennsylvania Game Commission confirmed Friday that three deer killed by hunters during the 2012 rifle deer season in Blair and Bedford counties tested positive for the neurological disorder, chronic wasting disease. In October, a farm-raised penned deer in Adams County tested positive in the state's first confirmed case of CWD.
The U.S. Centers for Disease Control and Prevention and the Pennsylvania Department of Agriculture have said there is no evidence CWD can be transmitted to humans or household pets.
Chronic wasting disease is progressive and always fatal in cervids including deer, elk and moose, impacting the infected animal's brain and nervous system. It is believed to occur when normal brain proteins are converted by an unknown agent to an abnormal form.
It is spread through the direct transfer of body fluids and through contaminated soil. There is no known treatment.
CWD was detected during routine random sampling by the state Department of Agriculture with confirmation by the National Veterinary Services Laboratories in Ames, Iowa. CWD was found in two hunter-killed deer in Bedford County and one in Blair County.
"The three CWD-positives were part of 2,945 deer sampled for the disease statewide," said Game Commission executive director Carl Roe, in a written statement. "To date, we have received test results from 1,500 samples, including these three positive samples. Results from the remaining samples should be available in the next few weeks."
An additional 2,089 deer samples were collected during mandatory testing of hunter-killed deer taken within the special Disease Management Area established in Adams and York counties following the discovery of CWD at the commercial deer farm in Adams County. The disease was not detected in those samples.
Agency spokesman Joe Neville said deer-processing centers in southcentral Pennsylvania were prioritized for random sampling because CWD had been previously confirmed in wild deer in nearby counties of Maryland and West Virginia.
The disease is not expected to be found in samples from northern or western counties. Increased sampling from road-killed deer and other sources in south central counties is expected to begin soon.
There is no way to test for CWD in venison from deer killed by hunters during the 2012-13 hunting seasons, said Mr. Neville. Because the disease cannot pass from cervids to humans, risk from ingesting meat from infected deer is "very low," he said. The state has not issued a consumption advisory for hunter-shot venison.
The Game Commission's priority, said Mr. Neville, is protecting the rest of the state's deer herd.
"We'll never get rid of [CWD] now that it's here, but we can slow its spread," he said.
The agency is expected to establish special hunting regulations in targeted areas and educate backyard wildlife watchers about their role in preventing the spread of CWD. Saliva and other fluids are passed among deer on wildlife feed. People should stop feeding deer and structure their bird feeders to prevent deer access.
More information about chronic wasting disease is available at the Game Commission's website, www.pgc.state.pa.us.
John Hayes: 412-263-1991, firstname.lastname@example.org.