© Thomson Reuters
Eastern equine encephalitis is a potential deadly but rare disease that causes brain damage.
If you needed another reason to use bug spray this summer, here it is: A rare virus that causes brain damage has been confirmed in mosquitoes in New York and Massachusetts, health officials reported last week.

Oswego County officials said the eastern equine encephalitis virus, or EEE, was discovered in two mosquito pools from a swamp about 20 miles north of Syracuse in a town called West Monroe, according to

The Boston Globe reported the virus has also been confirmed in mosquitoes south of Boston — in Easton, Freetown, and New Bedford. No human infections have been reported yet in either state this season.

EEE is a rare but life-threatening virus that can wreak havoc in livestock and cause permanent brain damage in people, resulting in seizures, mental impairment, and even personality changes in survivors of the disease.

It is most often found in the northeastern United States in swampy, wooded areas from late spring to early fall. It can also be found in Florida, Mississippi, Louisiana, Alabama, and Texas into the winter months.

There is no cure, but the disease, as well as others transmitted by mosquitoes, can be prevented by taking precautions against mosquito attacks. Here's what you need to know about EEE.

EEE is dangerous because it can inflame the brain

Only about 5 to 10 human cases of EEE are reported in the U.S. each year, according to the Centers for Disease Control and Prevention. But about 30% of cases are fatal, and survivors are often left with permanent brain damage.

After it's been transmitted via a mosquito bite, the virus can cause inflammation of the brain (encephalitis), which is what makes it so dangerous and potentially fatal.

If a mosquito with the virus bites you, you can experience symptoms like headache, high fever, chills, and vomiting four to 10 days afterward, according to the CDC. You'll know it's not something like the flu since it suddenly progresses into more serious symptoms like disorientation and convulsions.

A blood test or spinal fluid sample can diagnose the infection. Although there's no cure, patients should be hospitalized so symptoms can be treated. If the infection doesn't reach the brain, people can make a complete recovery within weeks.

However, if the brain does become inflamed, brain damage can be permanent and cause long-term problems like confusion, memory loss, changes in personality and mood, paralysis, and intellectual impairment. About a third of patients with EEE die, either within weeks of getting this disease or years later as a result of ongoing physical and mental impairment.

Anyone can get the disease, but people who work outside are particularly likely to be bitten by mosquitoes, and children and the elderly are most likely to have severe cases of EEE.

You can prevent all mosquito-borne illnesses by using effective bug spray (with DEET or lemon eucalyptus) while outside, and wearing long pants and sleeves, according to the CDC.

Health officials also recommend eliminating mosquito habitats where possible. That means getting rid of standing water from containers around the home like flower pots, gutters, recycling containers, wheel barrows, and birdbaths. Also make sure your screens don't have any holes or tears so that they keep mosquitoes outside.