YORK COUNTY — Area residents are being urged by the Maine Center for Disease Control and Prevention to take precautions against illnesses transmitted by mosquito  bites after mosquitoes in York County tested positive for Eastern Equine Encephalitis.

According to Maine’s Health and Environmental Testing Laboratory, presence of Eastern Equine Encephalitis was found in a single mosquito pool contained up to 50 mosquitoes collected Sept. 6 in Lebanon.

“This test confirms that mosquitoes carrying this potentially fatal virus are still active in Maine,” said Maine CDC Director Nirav D. Shah. “We urge residents and visitors to continue to take steps to protect themselves from mosquito bites.”

Eastern Equine Encephalitis is an extremely rare, but serious and often fatal infection that causes encephalitis or inflammation of the brain. It is spread by the bite of a mosquito infected with EEE virus and can also infect a wide range of animals including mammals, birds, reptiles, and amphibians.

The spread of the EEE Virus to mammals occurs through the bite of infected mosquitoes, but Shah said EEE cannot be transmitted from human to human or animal to human.

In August, Maine CDC reported that a horse in York County was euthanized after contracting EEE.

As a precautionary measure, Shah said that the Maine CDC advises minimizing outdoor activity from dusk to dawn, the time when mosquitoes are most active.

If outdoor activity is unavoidable, Maine CDC advised taking precautions to prevent mosquito bites including wearing protective clothing such as  long-sleeved shirts, long pants, and long socks; using an EPA-approved mosquito repellent and taking steps to control mosquitoes around property by emptying artificial sources of standing water, fixing holes in screens, and working with a pesticide control applicator.

Risk from mosquito-transmitted diseases such as EEE typically increases from late summer and in the early fall. Mosquitoes remain active until the second hard frost of the season.

Shah said that there have been no confirmed cases of EEE in humans in Maine this year and that the last case of EEE involving a human in Maine was in 2015.

Human infection with EEE virus can cause serious illness affecting the brain. Some persons infected with EEE have no obvious symptoms, but in those who do develop illness, initial symptoms may include fever, headache, weakness, and body and muscle pain.

Symptoms typically begin in four to 10 days after a bite from an infected mosquito, and usually last one to two weeks. In more serious cases, the disease may progress to swelling of the brain, neck stiffness, confusion, seizures, and coma.

For more information about EEE prevention, visit www.cdc.gov/eee.