Eastern Equine Encephalitis, more commonly known as “Triple-E,” is a rare but serious viral infection that is passed from mosquitoes to humans.  While many mosquitoes carry the virus, only a small percentage of humans develop neurological manifestations of the disease.  Unfortunately, there is no vaccine to prevent infection with Eastern Equine Encephalitis Virus, or medication that can be used to treat the virus once a person is infected.  Prevention of mosquito bites is the most effective way to prevent spread of the virus.  The best way to prevent mosquito bites are to wear long clothing, use DEET containing insect repellents on exposed skin, and avoid outdoor activities at dusk and dawn when the risk of mosquito bites is greatest. 

There are two types of infections that can occur when someone has been infected with Eastern equine encephalitis virus:  systemic and invasive.  Systemic infection is the most common type of infection and the symptoms are a flu-like illness that lasts 1 – 2 weeks.   People who have the systemic illness recover fully without any lasting effects.  People who have invasive disease begin with fever, weakness, joint/muscle pain, but after a few days develop severe headache, vomiting, and confusion or drowsiness.  Some individuals will have a seizure as well.  People who have symptoms of invasive disease need to seek medical care as soon as possible.  The Centers for Disease Control (CDC) has information about “Triple-E” that you might find informative and helpful.  Follow this link to the EEE section of our website where you can get more information from both the CDC and the Massachusetts Department of Public Health.