Parks and fields closed in Massachusetts cities due to deadly mosquito-borne virus

Local parks and fields have been closed in several counties in eastern Massachusetts following an outbreak of a rare and potentially deadly mosquito-borne virus.

The Massachusetts Department of Public Health (DPH) announced Saturday that it will begin aerial and truck-based mosquito control spraying efforts following the emergence of the Eastern Equine Encephalomyelitis (EEE) virus.

According to the agency, the virus is a “rare but serious and potentially fatal disease” that can affect people of all ages. On August 16, the first human case was recorded this year, a man in his 80s from Worcester County.

EEE is generally transmitted to humans through the bite of an infected mosquito. Symptoms may include fever, headache, vomiting, diarrhea, seizures, behavioral changes and drowsiness, according to the Center for Disease Control and Prevention (CDC).

About 30 percent of people with Eastern equine encephalomyelitis die, and many survivors have persistent neurological problems. There is no vaccine or treatment for EEE.

The first EEE-positive mosquitoes of the season in Massachusetts were reported in Carver on July 3, but others were previously identified in several other counties.

The DPH said trucks are spraying against mosquitoes in Plymouth County and parts of Worcester County. As of Saturday, 10 Massachusetts communities were identified as having a high or critical risk for electrical and electronic equipment, the agency said.

The eight communities in the spray zone are Carver, Halifax, Kingston, Middleborough, Plymouth, Plympton, Rochester and Wareham.

The five communities in the truck spraying zone are Douglas, Dudley, Oxford, Sutton and Uxbridge. Spraying is expected to take place over the next week and is scheduled to take place overnight.

“We have not seen an outbreak of electrical and electronic equipment in Massachusetts in four years,” said DPH Commissioner Robbie Goldstein.

“The outbreak and activities this year are increasing the risk to communities in parts of the state. We must use all the tools at our disposal to reduce the risk and protect our communities. We ask everyone to do their part.”

The last EEE outbreak in Massachusetts in 2019-2020 resulted in 17 human cases and seven deaths.

“Due to the increased risk of EEE and the first human case of the season, the state is taking decisive action to protect public health,” said MDAR Commissioner Ashley Randle. “Aerial spraying targets mosquitoes that transmit the EEE virus.”

“While these measures are critical to reducing the risk of transmission, it is essential for everyone to remain vigilant and follow personal protection guidelines to protect our community.”

The pesticide used is Anvil 10+10, which has been extensively tested and used in the United States for both ground and aerial spraying to control mosquitoes and is approved by the Environmental Protection Agency (EPA).

Residents of affected areas were also advised to avoid mosquito bites by using insect repellent, be aware of peak mosquito seasons, make their homes mosquito-proof and protect their animals.