There has been a confirmed positive human case of Eastern Equine Encephalitis (EEE) in Southern Plymouth County, which has now placed some area towns, including Rochester and Marion at “critical risk “ for human exposure to the virus. This is the first human case of the virus in Massachusetts since 2013.

The virus is transmitted by mosquitoes. It is rare but serious, and can lead to the swelling of the brain and death. Those under the age of 15 and over the age of 50 are most at risk.

As of Saturday, Aug. 10 the Massachusetts Department of Health and Human Services has listed the towns and cities of Marion, Rochester, Wareham, New Bedford, Acushnet, Lakeville, Freetown, Middleborough, and Carver at critical risk for EEE. A critical risk classification means that a person in the area has been infected. To prevent infections in a critical risk area, residents should cancel or reschedule outdoor activities to avoid peak mosquito hours (dusk to dawn).

The towns of Mattapoisett and Fairhaven remain at high risk of for the EEE virus. This means that conditions likely to lead to infection are occurring in the area. Under these conditions, residents should adjust outdoor activity to avoid peak mosquito hours, and avoid outdoor camping, especially near freshwater swamps where EEE activity is most likely.

The Town of Marion is closing all town beaches, parks, and events on town property after 6 p.m. due to the risk of EEE. The Marion Board of Health advises residents to use mosquito repellent when outside, and wear long sleeves and pants, to prevent mosquito bites.

Residents should also drain standing water from containers like buckets and tires, as these provide breeding grounds for mosquitoes.

Plymouth County began aerial spraying on August 8 to reduce human risk and will continue spraying tonight, Saturday, August 10. For a map of areas that will be sprayed, click here. Spraying will take place after dusk until about midnight.