For Immediate Release: August 18, 2023

Media Contacts:

Ben Truman
Vermont Department of Health 802-316-2117 | [email protected]   

Scott Waterman
Vermont Agency of Agriculture, Food & Markets
802-622-4662 | [email protected]


Mosquitoes Test Positive for Eastern Equine Encephalitis (EEE)
Vermonters are urged to take precautions against mosquito bites and potentially deadly mosquito-transmitted diseases

BURLINGTON, VT – Vermonters are urged to take steps to protect themselves against mosquito bites, as mosquitoes in Grand Isle and Franklin Counties have tested positive for Eastern equine encephalitis (EEE) — a serious and potentially fatal mosquito-transmitted infection. These are the first detections of EEE in mosquitoes in Vermont since 2015.

The Vermont Agency of Agriculture Food and Markets collects mosquitoes at locations throughout the state for testing at the Department of Health Laboratory. So far this season more than 824 mosquito pools have been sampled. The positive EEE samples were collected on August 8 from pools in Alburgh and Swanton. Earlier this month West Nile virus was detected among mosquitoes in Alburgh and Vergennes.

Eastern equine encephalitis (EEE) virus is spread through the bite of an infected mosquito. The risk of infection is highest from late summer into fall. It takes four to 10 days after being infected to develop symptoms. Most people infected with EEE will have no or mild symptoms, such as fever, chills, fatigue, joint and body aches. However, while rare, EEE can result in severe illness − including encephalitis, an inflammation of the brain. EEE is fatal in about one-third of people who develop severe EEE disease, and many who recover are left with disabilities. People with symptoms or who suspect exposure are encouraged to contact their health care provider as soon as they feel sick.

There have been no human cases of EEE in Vermont reported this year. The last confirmed cases were in 2012 and resulted in the death of two people. A 2010 study detected antibodies to EEE in deer and moose throughout the state, indicating the virus is widely present in the environment and in wildlife populations.

“EEE can be life-threatening. It’s important that people take this seriously and take measures now to protect themselves and their families from getting mosquito bites." said Health Commissioner Mark Levine, MD. “These results are site specific, but we know from experience that West Nile virus and EEE can potentially be found in many places around Vermont.”

There is no specific treatment or human vaccine for EEE. The best way to protect yourself and family is to prevent mosquito bites. The Health Department offers these simple and effective tips:

  • Wear long-sleeved shirts and pants when outdoors.
  • Limit your time outside at dawn and dusk when mosquitoes are more likely to bite.
  • Use insect repellent labelled as effective against mosquitoes. The EPA has a tool to help find the right repellent for you. These can also protect you from tick bites. 
  • Get rid of standing water in places like gutters, tires, play pools, flowerpots and bird baths. Mosquitoes breed in water that has been standing more than four days.
  • Cover strollers and outdoor playpens with mosquito netting.
  • Fix holes in screens and make sure they are tightly attached to doors and windows.

Horse owners should consult with their veterinarians and make sure their animals are up to date on vaccinations for EEE, West Nile and other viruses spread by infected insects or ticks. Horses cannot spread EEE or West Nile viruses to humans or other horses, but the viruses can cause neurologic disease and death in unvaccinated animals. In 2012, two unvaccinated horses died from the virus.

Agriculture officials said that the wet weather and statewide flooding have led to larger than usual mosquito populations. Vermonters are asked to remove standing water where possible to help limit places where mosquito larvae can hatch and grow into adults. You can eliminate mosquito breeding sites by emptying standing water from flowerpots, buckets, barrels and other containers. Drill holes in tire swings so water drains out. Keep children’s wading pools empty and on their side when not being used.

For more information about EEE, visit

Learn how to prevent mosquito bites at

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About the Department of Health
We have been the state's public health agency for more than 130 years, working every day to protect and promote the health of Vermonters.
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About the Agency of Agriculture, Food & Markets
The Vermont Agency of Agriculture, Food & Markets (VAAFM) facilitates, supports and encourages the growth and viability of agriculture in Vermont while protecting the working landscape, human health, animal health, plant health, consumers and the environment.

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