First MA Human West Nile Virus Case Of Season Confirmed

MASSACHUSETTS — A Middlesex County woman in her 70s became the first confirmed human case of West Nile Virus in Massachusetts this year, according to the Massachusetts Department of Public Health on Tuesday.

The first WNV positive mosquitoes in the state this year were announced on June 17. There have been 319 WNV-positive mosquito samples so far this season detected from Barnstable, Berkshire, Bristol, Dukes, Essex, Franklin, Hampden, Middlesex, Norfolk, Plymouth, Suffolk, and Worcester counties.

There has also been one WNV infected goat identified this year.

• More North Shore West Nile Virus-Positive Mosquitoes As Threat Level Rises

The state DPH said the risk for WNV is high in 10 municipalities in Suffolk and Middlesex counties and moderate in 193 municipalities in Barnstable, Berkshire, Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, Norfolk, Plymouth, Suffolk, and Worcester counties.

"West Nile virus can be a very serious disease and its presence in mosquitoes remains high right now in Massachusetts," said Public Health Commissioner Robbie Goldstein. "While September brings cooler air and the return to school for many in the state, the risk from WNV is going to be elevated for some time.

"Residents should continue to take precautions to avoid mosquito bites."

There have been 18 Eastern equine encephalitis (EEE)-positive mosquito samples and no human or animal cases so far this year.

"The mosquitoes will be with us until the first hard frost," said State Epidemiologist Dr. Catherine M. Brown. "People should use mosquito repellent with an EPA-registered active ingredient, clothing to reduce exposed skin, and consider rescheduling outdoor activities that occur during the evening or early morning."

Multiple positive mosquito samples were identified in Danvers within the past three weeks. The Danvers and Peabody Health Departments said the risk level was raised from low to moderate in both communities as of late last week.

WNV is most commonly transmitted to humans by the bite of an infected mosquito. The mosquitoes that carry this virus are common throughout the state and are found in urban as well as more rural areas.

While WNV can infect people of all ages, people over the age of 50 are at higher risk
of severe infection.

(Scott Souza is a Patch field editor covering Beverly, Danvers, Marblehead, Peabody, Salem and Swampscott. He can be reached at Scott.Souza@Patch.com. X/Twitter: @Scott_Souza.)