State health officials announce season’s first positive West Nile virus mosquito sample detected in MA


BOSTON, MA. (NEWS10) — The Massachusetts Department of Public Health (DPH) announced Thursday that West Nile virus (WNV) has been detected in mosquitoes in Massachusetts for the first time this year.

The presence of WNV was reportedly confirmed Thursday by the Massachusetts State Public Health Laboratory in two mosquito samples collected July 7 in the town of Belmont in Middlesex County.

No human or animal cases of WNV or Eastern Equine Encephalitis (EEE) have reportedly been detected so far this year. Health officials say there is no elevated risk level or risk-level change associated with the finding. 

“The first WNV positive mosquito sample has been identified this year in Massachusetts,” said Public Health Commissioner Monica Bharel, MD, MPH. “It is important to remember that WNV can cause very serious illness, especially in individuals over 50 and those who are immune compromised.”

WNV is usually transmitted to humans through the bite of an infected mosquito. There were five human cases of WNV reported in 2019. In 2018, there were 49 human cases of WNV infection recorded in Massachusetts – reportedly the greatest number of cases the Commonwealth has ever had in a single year.

Health officials say while WNV can infect people of all ages, people over the age of 50 are at higher risk for severe disease. Most people infected with WNV will have no symptoms. When present, WNV symptoms tend to include fever and flu-like illness. In rare cases, more severe illness can occur.

“People have an important role to play in protecting themselves and their loved ones from illnesses caused by mosquitoes,” said State Epidemiologist Dr. Catherine Brown. “The tools for prevention include using a mosquito repellent with an EPA-registered ingredient according to the directions on the label, wearing clothing to reduce exposed skin when weather permits, draining standing water to prevent mosquito breeding and repairing window screens to keep mosquitoes out of your home,” she said.

Information about current mosquito activity in Massachusetts is updated daily and can be found here.


Follow NEWS10

Copyright 2021 Nexstar Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Download our news app

App Store Link
Google Play Link

Click Below to set up your cable box

Latest COVID-19 News

More COVID-19

Cuomo Under Fire News

More Cuomo Under Fire