Pennsylvania Sounding the Alarm on Chronic Wasting Disease Among Deer

Pennsylvania's efforts to control the spread of Chronic Wasting Disease have spread into Berks County, the closest to the Lehigh Valley since the illness was first confirmed in the state in 2012.

Experts say Pennsylvania's white-tailed deer and hunting culture aren't facing a CWD catastrophe. Yet.

But state game and agriculture officials are calling for a unified effort on the part of hunters and other outdoors enthusiasts, along with deer farmers, to avoid becoming another Wisconsin. Some parts of that state are seeing half their deer population infected, said Wayne Laroche, special assistant to the Pennsylvania Game Commission for Chronic Wasting Disease.

"They're probably not ever going to get rid of that unless we come up with some novel ways of disinfecting the landscape," Laroche told a recent meeting on CWD set up by state Rep. Marcia Hahn, R-Northampton, at the East Bath Rod and Gun Club in East Allen Township.

Hunting in Pennsylvania is a $1.6 billion industry, Hahn said.

"So we want to make sure that we keep hunters happy, for one, that we can keep the economy going," she said Wednesday. "It generates a lot of tax revenue for us and helps the state."

Chronic Wasting Disease affects members of the cervid family: black-tailed deer, elk, moose, mule deer, red deer, reindeer, sika deer and white-tailed deer, and hybrids of these species.

It was first confirmed in the United States in 1967, in northern Colorado. Now it's in almost half the states in the nation. Along with Pennsylvania, it's since been found in Arkansas, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Mexico, New York, North Dakota, Ohio, Oklahoma, South Dakota, Texas, Utah, Virginia, West Virginia, Wisconsin, Wyoming and Alberta and Saskatchewan in Canada.

Regionally, the disease turned up in eastern West Virginia in 2005, northern Virginia in 2009 and western Maryland in 2010 — all near the Pennsylvania border.

It's been confirmed in 177 free-ranging deer in Pennsylvania since 2012, including 78 in 2017 and 26 through June 2018.

"This disease doesn't respect bounds, OK, this is not a PA problem," Dr. Kevin Brightbill, a veterinarian leading the fight against CWD for the Pennsylvania Department of Agriculture, told the gun club meeting. "This is kind of an East Coast-Maryland-West Virginia-PA problem. ...

"I'm here to say I don't care where it came from. If we care about this, if we care about our hunting future, we need to think about strategies that wildlife enthusiasts, captive cervid facilities, hunters, how we can all come together and mitigate this."

Similar to mad cow disease in cattle and scrapie in sheep, CWD is part of the family of diseases known as transmissable spongiform encephalopathies. It's caused by an abnormal protein, called a prion, rather than a living organism like a virus that an animal's immune system could fight.

There is no treatment, no cure and no vaccine.

"And so animals start wandering around, ears drooping, salivating, falling down and end up dying 18 to 24 months usually after they're infected," Laroche said. "It's only in those last stages that you see signs. ... And any animal getting the infection always dies. ...

"They all die in the end."

CWD is not known to affect humans. The U.S. Centers for Disease Control and Prevention has been surveilling for increased incidences of Creutzfeld-Jakob Disease, linked to mad cow, to look for spikes possibly associated with Chronic Wasting Disease, according to Laroche. There's been no evidence of human infections.

It spreads between cervids through feces, urine and saliva. The prion can remain infectious outside an animal for up to 15 years, Laroche said. That could lead to deer picking up the infection from the environment if enough prions accumulate -- at a deer farm's watering station, for example.

On the first day of the 2012 firearms deer season, hunters bring deer taken within the Disease Management Area in Adams and York counties to a Pennsylvania Game Commission testing station for Chronic Wasting Disease at State Game Lands 249.

With an incubation period of up to two years, a CWD infection generally is not evident in deer. If an animal does appear ill, the experts at the gun club told the audience of about 40 people to avoid eating any of its meat. CWD is just one animal disease to be concerned about, in addition to avian flu, tuberculosis and brucellosis, to name a few.

"However, animal studies suggest CWD poses a risk to some types of non-human primates, like monkeys, that eat meat from CWD-infected animals or come in contact with brain or body fluids from infected deer or elk," the CDC says. "These studies raise concerns that there may also be a risk to people."

As a precaution, the CDC recommends against eating meat from deer and elk that test positive for CWD. State officials advise wearing protective gloves when field-dressing a deer, and say hunters should ask their butcher to process only their kill instead of mixing it with the meat of other deer.

The state asks hunters or other wildlife enthusiasts who see a deer they suspect might have CWD to call their regional Pennsylvania Game Commission office. A hunter who shoots a suspected ill deer can get another tag for another deer from a game warden, according to Laroche.

To stem the spread of CWD, Pennsylvania has established four Disease Management Areas in south-central Pennsylvania. DMA 1 was dissolved following control measures put in place at the Adams County captive deer farm where the disease surfaced in 2012.

DMA 4 is the furthest east, extending to Reading in Berks County. This area was set up in 2018, following the discovery of CWD in a captive deer at a farm in neighboring Lancaster County.

More than 5,895 square miles of Pennsylvania lie within DMAs.

Prohibited within DMAs are the rehabilitation of cervids; use or possession of cervid urine-based attractants in an outdoor setting; removal of high-risk cervid parts like the spinal cord/backbone and head; and the feeding of wild, free-ranging cervids.

For deer killed within a DMA, the Game Commission offers free testing of heads dropped into any of the CWD Collection Containers set up around these areas. The only reliable testing for CWD is done on the brain stem and lymph nodes of a deer carcass.

The meat, hide and antlers attached to a clean skull plate may be removed from a DMA.

"Don't consume high-risk parts," the Game Commission says on its website. "Normal field-dressing, coupled with boning out a carcass, will remove most, if not all, high-risk parts. Cutting away all fatty tissue will remove remaining lymph nodes."

Pennsylvania tested 7,910 free-ranging deer and 128 elk for CWD in 2017, up from 5,707 deer and 110 elk in 2016. Since 2002, the Game Commission has tested over 69,000 deer for CWD.

According to Laroche, the Game Commission biologist, deer have been shown to demonstrate a range of resistance to CWD. For that reason, experts do not recommend eradicating a wild herd where CWD is found, in the hopes that generations pass on the resistance.

"But the truth of the matter is if we don't solve this problem the way it rose as we see in Wisconsin, Wyoming, West Virginia, Colorado, the future of deer hunting for your kids and your grandchildren will definitely be in jeopardy," Laroche said last week in Northampton County. "So we have to be serious about this and we have to be committed to do what we have to do and maybe sacrificing a little bit in order to get the job done."