What You Need To Know About EEE

You may have seen headlines about EEE (Eastern Equine Encephalitis) and brushed past them either out of denial (seriously, another thing?!) or because of the very real overwhelm that is back-to-school season. I will admit to maybe a little of each of those things, but given that we got our first city robocall about spraying and given that EEE is now a topic of conversation on the soccer sidelines (where I'm now spending a lot of time), EEE is very top of mind. I’m so grateful to Attending Physician and Associate Director of the Infectious Diseases Fellowship Program, Brian D. W. Chow, MD, for answering these pressing questions that I wanted to get answered for you!

What is EEE and what happens if you get it?

Eastern Equine Encephalitis (EEE) is a virus transmitted from a mosquito bite. It normally lives in birds, but certain mosquitoes that bite both birds and humans can pass the virus to humans. 

It is estimated that in the vast majority of cases, about 95%, the person will fight off the virus with only a mild illness. In the remaining 5%, the virus will travel to the brain and cause encephalitis—inflammation and swelling of the brain. 

Most cases will start with a mild illness and fever. Cases of encephalitis will develop signs and symptoms about 3-4 days into the illness. This can include headache, drowsiness, confusion, and/or change in personality. Of people who develop encephalitis, even with modern medical care, about one-third will die, and many survivors will have long lasting nervous system problems.

Are there treatments available?

There is no vaccine for EEE, and there is no medicine which acts directly against the virus. Doctors and nurses support the body’s functions as the body heals.

What is the prevalence in MA?

EEE comes and goes. The last outbreak in Massachusetts was in 2012. Between then and now, we had no cases of EEE.  However this year, we have had 8 total cases of encephalitis due to EEE as of today.

How you can protect yourself and your family?

Keep from getting bitten by mosquitoes! Here are some tips:

  • The mosquitoes that transmit EEE bite between dusk and dawn. Avoid spending time outdoors during these times if you can.

  • Ensure that you sleep with windows closed.

  • If you have screens, make sure they are in good repair and have no holes where mosquitoes can get inside. 

  • While outside, wear clothes that will cover up as much skin as possible to reduce areas where mosquitoes can bite.

  • Wear a CDC recommended insect repellent, such as DEET or oil of lemon eucalyptus. 

  • Make sure you get rid of standing or stagnant water to reduce placed where mosquitoes can breed.

What you should ask of your town/city for further protection?

Ask about any plans for spraying for mosquitoes and instructions on what do while they are spraying in your neighborhood. The Massachusetts Department of Public Health maintains maps showing the risk for EEE in your area.

To contact Brian Chow, call 617-636-7010 or request an appointment on our website.


Tufts Medical Center is a renowned not-for-profit academic medical center in downtown Boston. Floating Hospital for Children is the full-service children’s hospital of Tufts Medical Center. Both are the principal teaching hospitals of Tufts University School of Medicine. Tufts MC and the Floating Hospital offer a full range of services including primary care, OBGYN services in all areas of women’s health, and dedicated pediatric and adult emergency rooms.

Disclaimer: The content provided in this post is intended solely for the information of the reader. This information is not medical advice and should not replace a consultation with a medical professional.

Disclosure: This post reflects a compensated editorial partnership. Personal commentary by Christine Koh is, of course, her own!

What you need to know about EEE (Eastern Equine Encephalitis)

What you need to know about EEE (Eastern Equine Encephalitis)