GREENVILLE, N.C. (WNCT) — The Eastern Equine Encephalitis (EEE) virus has recently been identified in Eastern North Carolina. Horses in three counties — Brunswick, Pender and Onslow — were recently diagnosed with EEE.

In addition, the EEE virus was detected in a mosquito sample from New Hanover County. No human cases of EEE have been identified in North Carolina so far this year. 

The EEE virus is transmitted by the bite of infected mosquitoes. It can cause serious illness in people as well as horses, donkeys, emus and ostriches.

“It’s a vaccine preventable disease from horses and it’s an opportunity for people to be reminded that it’s a virus that does exist,” said Carl Williams, state public health veterinarian.

Although uncommon in people, EEE is one of the most severe mosquito-transmitted diseases in both horses and humans in the United States. Approximately a third of people who become ill with EEE die.

Many people who survive EEE suffer from long-term brain damage. Those under age 15 and over age 50 are at greatest risk of developing severe disease. From 2003 to 2020, 12 human cases of EEE were reported in North Carolina, with infections occurring from July through December.

We want people to try and prevent mosquitoes bites, because some mosquitoes, especially in the eastern part of the state, can carry that virus. It’s a very rare disease in humans, but we want to take this opportunity to educate people to use prevention measures.

Carl Williams, state public health veterinarian

In North Carolina, EEE virus is most commonly detected in the eastern part of the state, where the virus is normally passed between wild birds and mosquitoes. The mosquito species that is the main carrier of EEE spends most of its time in freshwater swamps and almost exclusively bites birds rather than horses and humans.  

“The local health departments examine the mosquito control program. Part of their job is to determine what species of mosquitoes are present, where they are, and are they infected with any viruses that could affect people or animals,” Williams said.

“The local health departments in these counties will be testing the mosquitoes to determine if there is West Nile virus or ‘triple-E’ present. Those are the two that are most concerning, and if they find them, that’s an opportunity to let people know that they could be passed to a human, so, take prevention measures.” 

People can protect themselves from EEE by preventing mosquito bites. Consistent use of effective mosquito repellents during the months when they are active is important. A second method is mosquito control efforts, especially in areas near freshwater swamps. There is no vaccine to protect humans from EEE, and no cure once a human is infected. Treatment is limited to managing the symptoms of the disease.

“Avoid times that mosquitoes are active, like from dusk to dawn, from the extent that you can,” said Williams.

Autumn is also the time of year when most cases of other mosquito borne viral illnesses are reported, such as West Nile virus and La Crosse virus infections. To prevent mosquito-borne illness, NCDHHS’ Division of Public Health encourages people to practice the “3 Ds”:

  • Dress – Wear loose, light-colored clothing that covers your skin.
  • Defend – When the potential exists for exposure to mosquitoes, repellents containing DEET (N,N-diethyl-meta-toluamide) are recommended. Picaridin and oil of lemon eucalyptus are other repellent options. Learn more about insect repellent options
  • Drainage – Check around your home to rid of standing water, which is where mosquitoes can lay their eggs.  

“It’s not something people should live in fear of, but just be aware of it and take common sense steps that you have heard before,” said Williams. “That will not only help eliminate or reduce mosquito bites, but also tic bites.” 

Helpful prevention tips for around the home can be found here.

If you have specific questions pertaining to EEE in humans, please contact the Communicable Disease Branch at (919) 733-3419. For questions about EEE in horses, please consult your veterinarian or the North Carolina Department of Agriculture and Consumer Services, Veterinary Division, at (919) 733-7601.