A rare mosquito-transmitted virus that can be fatal to humans was recently confirmed in a deer found in Luzerne County.
On. Oct. 9, the Pennsylvania Game Commission received a report of an emaciated deer standing on Swamp Road in Hunlock Twp.
According to the agency, the deer — a doe — stood with its head down and didn’t respond when humans approached. The animal was euthanized by Game Commission officials, and subsequent testing revealed it was infected with Eastern equine encephalitis.
While there have been no reported cases of EEE in humans in the state, there have been several confirmations of the virus appearing in wildlife and livestock during October.
In addition to the deer in Hunlock Twp., EEE has also been found in captive pheasants in Monroe County, horses in Carbon County and two wild turkeys in Erie County.
Kevin Wenner, a biologist with the Game Commission in the Northeast Region Office, said the deer in Hunlock Twp. represents the first instance of EEE in wildlife in the area, but it’s difficult to predict if more cases will follow.
“We’re not experiencing any significant mortality with deer and this happens to be one individual that was tested,” he said. “It’s possible that we’re not aware of every case because a sick animal could die and never be found, but we’re not getting an increase in calls regarding sick deer.”
Equine encephalitis is transmitted to people, mammals and birds through the bites of mosquitoes that have fed on infected birds. Most birds with EEE do not show any symptoms and never become ill. However, EEE can cause illness and death in some bird species — most often pigeons, pheasants, turkeys and quail.
According to the Centers for Disease Control, symptoms of EEE in people develop four to 10 days after being bitten by an infected mosquito.
There are two types of illness that occur — systemic and encephalitic. The former resembles flu-like symptoms and lasts up to two weeks. In the case of encephalitic illness (swelling of the brain), approximately a third of all people afflicted die from the disease, according to the CDC. An average of seven human cases of EEE are reported annually in the United States.
While the occurrence of EEE is not widespread in the region or state, Wenner said the threat will go away once cold weather arrives and knocks out the mosquito population.
“It sounds like this is a disease that comes and goes. It’s not new, but we’ll go through stretches where there are no cases for years and then it shows up,” he said.
But right now, EEE is here, and since the disease has infected a deer in the wild, what does it mean for hunters? With archery deer season remaining open until Nov. 16 and the statewide firearms season set to begin on Nov. 30, are hunters at risk simply contacting a deer that harvest?
“There shouldn’t be a fear that every deer out there has this and they shouldn’t be consumed,” Wenner said. “It’s pretty uncommon in deer, and while people shouldn’t be scared, they should be aware and take simple precautions to help prevent exposure.”
Additionally, EEE can only be transmitted via a bite from an infected mosquito and not by direct contact, such as field dressing a deer. There is also no evidence that transmission can occur from consuming the meat of an infected animal, according to the Game Commission.
And even though birds are the primary host for the virus, Wenner said it doesn’t mean that people should refrain from feeding birds.
“Just take the necessary precautions to avoid being bitten by mosquitoes, such as using repellent and getting rid of any standing water around your home,” he said.
Equine encephalitis is one of several diseases in Pennsylvania that can impact deer. Chronic wasting disease turned up in 2012 and has spread through parts of the south-central and south-western areas of the state, and epizootic hemorrhagic disease — which is transmitted by biting flies — has turned up in Pennsylvania in localized areas since 2002.
“It makes you think,” said Game Warden Gerald Kapral, whose district includes Hunlock Twp. “Everyone sees a sick deer and they assume its chronic wasting disease, but this EEE case is an example that there’s more out there.”
