Mosquitoes infected with Eastern equine encephalitis have been detected in the state for the first time this year, the Massachusetts Department of Public Health said Wednesday.
The mosquito samples were collected earlier this week in Easton, and two of the four positive samples came from a mammal-biting type of mosquito, meaning people are at risk of being infected through bites from the insect.
“Today is our first indication this year that EEE is circulating in our environment, and it’s circulating early,” said state epidemiologist Dr. Al DeMaria. “This is also an important reminder for individuals to take simple, common-sense steps to avoid getting bitten by mosquitoes.”
State health officials have raised the threat level of mosquito-borne illness in the towns of Easton, Raynham, and Taunton from “moderate” to “high,” prompting state and local officials to begin discussions about mosquito-control efforts, which could range from canceling events to aerial spraying.
“As of right now, all activities on town and school properties must cease immediately from dusk to a half-hour after dawn until further notice,” said Alan Perry, a Raynham health agent. “The town is advising all outdoor activities on all properties be curtailed during those hours.”
Mosquitoes infected with West Nile virus have also been found this year in Massachusetts. Although there have been no human cases of West Nile or Eastern equine encephalitis reported so far, new state guidelines allow aerial spraying to occur earlier and more often to battle the illnesses. The state was criticized by some Southeastern Massachusetts residents for not proactively spraying pesticides last summer and putting them at risk. A Raynham man died of encephalitis last September, one of two people known to have been infected in the state last year. The other was a tourist.
“The DPH knows we have a community that’s been a huge advocate of aerial spraying so the ball is in their court,” said Perry, who also said the town has a vigorous ground spraying program already in place with Bristol County Mosquito Control. “We expect them to make a decision in the next few days.”
To avoid mosquito bites, health officials urge people to apply insect repellent containing DEET, permethrin, picaridin, oil of lemon eucalyptus or IR3535 when they go outdoors; and stay inside around dawn and dusk, or wear long-sleeved clothing, pants, and socks if you do go out.
EEE symptoms include a high fever, stiff neck, headache, and fatigue, and show up three to 10 days after a bite from an infected mosquito.
Globe correspondent Christine Legere contributed to this
report. Sarah N. Mattero
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