Earlier this year, just 10 miles across Pennsylvania's border in Maryland, chronic wasting disease (CWD) was confirmed in a yearling male white-tailed deer.
That is a little too close for comfort.
In 2005, CWD was found in Hampshire County, W. Va., 26 miles from the Pennsylvania border.
The disease probably now exists in Pennsylvania, said Dr. Walt Cottrell, wildlife veterinarian for the state Game Commission, although the commission has not released information on any identified cases.
"This is an expanding disease and it does not care about political boundaries," he said.
"I would say this, it wouldn't surprise me that it is already here," Cottrell said. "I think there is every reason to believe that it is here."
CWD can affect elk and deer in Pennsylvania. It has the potential to devastate the state's herds of both species.
What is it?
The disease is a transmissible spongiform encephalopathy, or TSE, believed to be caused by an abnormal prion found in the brain. A prion, Cottrell said, is an infectious protein particle.
It causes brain damage and behavioral changes. An infected animal doesn't eat and loses weight, characterizing the disease's name - chronic wasting.
The infectious agent isn't a virus or a parasite.
"Prions in general are not like any other disease agent we know of," Cottrell said.
It can bond with soil particles, which makes it capable to survive in animals' digestive tracts. Infections of CWD have been found in not just the nervous system but also in blood, urine and saliva.
Because it can be found in urine and saliva, artificial feeding and even the use of urine-based lures made from unknown sources and in unknown areas could pass the disease.
With artificial feeding, deer will concentrate at a feeding site, resulting in a greater chance for exposure to the prions from other infected deer.
"The prions are taken in by mouth either directly through contaminated animal secretions or indirectly through the environment. They then exit the gastrointestinal tract and migrate up the local nerves to the spinal cord, then to the brain and also to lymph nodes," Cottrell said.
Is there a cure?
An infected animal doesn't show signs of the disease right away, he added. The disease has a very long incubation period - it can take anywhere from 24 months to five years before an animal may show signs of having it.
Males seem to be more affected than females, Cottrell said.
There is no cure or immunization available for CWD.
And, the disease always is fatal.
Cottrell said the Game Commission has tested about 30,000 animals of both species - elk and deer - since 2002. So far, all of the tests have been negative for chronic wasting disease.
Tests are conducted on certain areas of the brain of dead animals.
CWD first was discovered in the late 1960s in captive mule deer in Colorado.
Cottrell calls the importing of live deer and elk from areas where they have tested positive for CWD is one of the biggest threats for states where the disease has not yet reached.
"Some states, like Pennsylvania, have no ban on importation of live cervids from CWD-positive locations," Cottrell said in an article published in Pennsylvania Game News.
Pennsylvania ranks second to Texas for the number of captive cervids.
Pennsylvania has a "parts ban" on the importation of carcasses from CWD locations.
Hunters harvesting deer, elk or moose in states with CWD cannot bring back the following body parts: the head (including brain, tonsils, eyes and lymph nodes) spinal cord/backbone, spleen, skull plate, as well as other body parts.
Without a doubt, if the disease establishes itself in Pennsylvania, it will change the deer and elk herds here forever, Cottrell said.
In states such as Wyoming and Colorado, where the disease has been present for a long time, the mule deer population has undergone drastic cuts.
"We now see mule deer declining in areas where CWD has been present for some time - up to 48 percent of those populations are infected. Once the disease is established in Pennsylvania, we can expect that same behavior in our population over time, too," he said.
In a Wisconsin zone in which CWD exists, one in every four adult male deer have been affected by it.
Cottrell said hunters and residents in Pennsylvania can help reduce the spread of the disease by learning about it, obeying the CWD Parts Ban, reporting deer that look ill, eliminating artificial feeding and salt licks, and not using urine-based lures.
Game Commission personnel also plan to collaborate with colleagues in nearby states.