4th Human Case Of West Nile Reported In MA; Infection Risk Raised In 12 Towns

SHREWSBURY, MA — This year's fourth human case of West Nile Virus in a Massachusetts resident was reported recently. The state Department of Health said the individual is a man in his 60s who was exposed in Norfolk County.

The state also raised the risk level of both West Nile and Eastern Equine Encephalitis (EEE) infection in many towns and cities.

The risk of human infection with West Nile was already classified as moderate in the Greater Boston area, including Middlesex, Norfolk, and Suffolk counties, and in parts of Berkshire, Bristol, Hampden, Hampshire, Plymouth, and Worcester counties.

Twelve additional municipalities are now also considered to be at moderate risk: Ashland, Holliston, Hopkinton, and Sherborn in Middlesex County; and Dover, Medfield, Medway, Millis, Norfolk, Norwood, Walpole, and Westwood in Norfolk County.

Public health officials noted that once the weather becomes cooler, mosquito activity will be reduced. However, there will be some risk of mosquito-borne disease until the first hard frost.

West Nile Virus can infect people of all ages, but the health department noted that those over age 50 are at the highest risk for severe disease. Most people infected with the virus will have no symptoms. When symptoms do occur, they tend to include fever and flu-like illness. In rare cases, more severe illness can occur.

Risk for EEE infection is moderate or high in southern parts of Hampden, Norfolk, and Worcester counties. There have been EEE-infected animals identified in both Rhode Island and Connecticut.

As EEE-positive mosquitoes have recently been identified in Massachusetts, the health department has added thirteen municipalities to its moderate risk list: Easton, Norton, Raynham, Rehoboth, and Taunton in Bristol County; Agawam, Chicopee, Holyoke, Longmeadow, and West Springfield in Hampden County; Bridgewater, and West Bridgewater in Plymouth County; and Warren in Worcester County.

EEE is a rare but serious and potentially fatal disease that affects people of all ages. In 2019, Massachusetts had 12 human cases of EEE resulting in six deaths. There were no human cases of EEE in the state in 2021 or 2022.

The best way to prevent West Nile and EEE infection is to protect yourself against mosquito bites, state health officials said. Safety measures can include using mosquito spray containing DEET, treating clothes with permethrin, avoiding peak mosquito hours around dawn and dusk, and wearing pants and long sleeves. Homeowners should also drain standing water to prevent mosquitoes from breeding.