Mosquitoes with dangerous EEE virus found in Mass. for first time in 2024

The state hasn't found any human or animal cases of EEE so far this year.

The Massachusetts Department of Public Health is reporting the first Eastern equine encephalitis (EEE) virus detected in mosquitoes in the state this year.

EEE was confirmed in mosquito samples collected on June 30 in Carver. The state has not found EEE cases in humans or animals yet this year.

The findings, reported on July 3, increase the risk level of EEE to moderate in the communities of Carver, Kingston, Middleborough, Plymouth, Plympton and Wareham.

EEE is a rare but serious and potentially fatal disease that can affect people of all ages. EEE is spread to humans through the bite of an infected mosquito.

There were 12 cases in people in Massachusetts in 2019, with six deaths. In 2020, there were five cases and one death. No cases were found in people in 2021, 2022, or 2023.

“EEE activity in Massachusetts tends to occur in outbreak cycles,” said state epidemiologist Dr. Catherine Brown, in a statement. “When EEE is found in mosquitoes like this at the start of the season, the risk may increase throughout the rest of the summer. We rely on our mosquito surveillance program to monitor for the presence of virus to let people know when and where the risk is occurring.”

The announcement of EEE follows the announcement of West Nile virus detected in mosquitoes earlier this week.

“We are asking everyone to take the necessary precautions to prevent mosquito bites,” said Public Health Commissioner Robbie Goldstein in a statement.

How to avoid mosquito bites:

• Apply insect repellent when outdoors
• Be aware of peak mosquito hours, which are from dusk to dawn.
• Clothing can help reduce mosquito bites. Wear long sleeves, long pants, and socks when outdoors.

Mosquito-proof your home:

• Reduce potential mosquito breeding sites by eliminating standing water from containers such as buckets, tires and wading pools.
• Install or repair screens to keep mosquitoes outside.

Protect your animals:

• Water troughs provide excellent mosquito breeding habitats and should be flushed out at least once a week during summer to reduce mosquitoes near paddock areas.
• Horse owners should keep them in indoor stalls at night to reduce their risk of exposure to mosquitoes.
• Owners can also speak to their vets about mosquito repellents approved for animals and vaccinations to prevent West Nile Virus and EEE.
• If an animal is suspected of having West Nile Virus or EEE, it must be reported to the Department of Agricultural Resources, Division of Animal Health, by calling 617-626-1795, and to the Department of Public Health, by calling 617-983-6800.