Two towns south of Boston now have ‘high’ EEE risk, state says

Authorities are warning residents in some South Shore towns to be aware of a mosquito-borne illness called Eastern equine encephalitis (EEE).

The rare — but very dangerous — disease was detected in mosquito samples collected in various townships in the past few days, the Massachusetts Department of Public Health (DPH) announced. 

The EEE risk level in Carver and Middleborough is now “high,” according to DPH. Bridgewater, Lakeville, and Rochester are now at a “moderate” EEE risk level. Authorities detected the first EEE-positive mosquitoes in early July in Carver.

EEE is a serious concern for horses and their owners. The DPH says horses should be kept in indoor stalls at night to reduce their risk of exposure to mosquitoes, and make sure they are vaccinated against mosquito-borne illnesses. Owners are required to report any suspected or confirmed cases of EEE or West Nile Virus 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.

“Everyone should take the recommended steps to prevent mosquito bites,” Public Health Commissioner Robbie Goldstein said. He says people in “high risk areas” should use mosquito repellent whenever outside, and limit outdoor activities that take place in the evening or early morning.

“The mosquitoes that are most likely to spread EEE are most active between the hours of dusk and dawn,” said State Epidemiologist Dr. Catherine M. Brown. “They are also more active during hot and humid weather. We all want to enjoy this last month of summer but also want people to take steps to be safe from mosquitoes.”

Massachusetts authorities reported 12 human cases of EEE in 2019, with six fatalities. There were five human cases and one death in 2020, and no cases reported from 2021 to 2023. 

How to protect yourself from EEE

The DPH gave several ways to protect yourself and your home from EEE, including just avoiding mosquito bites. 

• Use mosquito repellent with an EPA-registered ingredient
• Avoid being outside at dusk and dawn, when mosquitoes are most active
• Wear long sleeves, long pants, and socks, when outside
• Mosquito-proof your home by draining standing water and installing or repairing window screens

These towns have had EEE detected in mosquitoes this year, according to DPH.

• Abbington
• Amesbury
• Bridgewater
• Groveland
• Halifax
• Haverhill
• Kingston
• Lakeville
• Merrimac
• Middleborough
• Newburyport
• Plymouth
• Plympton
• Rochester
• Salisbury
• Wareham
• West Newbury
• Whitman