State Public Health Officials Announce Season’s First EEE-positive Mosquito Sample

BOSTON — The Massachusetts Department of Public Health (DPH) announced that eastern equine encephalitis (EEE) virus has been detected in mosquitoes in Massachusetts for the first time this year. The presence of EEE was confirmed by the Massachusetts State Public Health Laboratory in two mosquito samples that were collected July 15 in the communities of Easton and New Bedford in Bristol County. No human or animal cases of EEE have been detected so far this year. There is no elevated risk level or risk-level change associated with this finding.

“It has been several years since we have had significant EEE activity in Massachusetts,” said DPH State Epidemiologist Dr. Catherine Brown. “This is a relatively normal time of year for the first evidence of EEE; continued mosquito surveillance over the next several weeks will help us understand how active this season will be.”

EEE is a rare but serious and potentially fatal disease that can affect people of all ages. EEE is generally spread to humans through the bite of an infected mosquito. The last human case of EEE in Massachusetts occurred in 2013. At the end of the 2018 season, EEE infection was confirmed in a turkey and a horse from Worcester County.

“People have an important role to play in protecting themselves and their loved ones from illnesses caused by mosquitoes. Now that we have evidence that both West Nile virus and EEE are present this season, it is very important to take steps to prevent exposure to mosquitoes,” Brown said. “We are also asking people to remain aware about the level of virus activity in areas where they live, work, and play.”

Current activity information can be found at the DPH website, www.mass.gov/dph/mosquito, which is updated daily.