A Massachusetts man has been diagnosed with the Eastern Equine Encephalitis (EEE) virus infection, the state's Department of Public Health announced Saturday.
Laboratory testing confirmed the virus in a Rochester man who is older than 60.
This is the first human case of EEE in the state since 2013.
As a result, officials raised the risk to critical in the following nine communities: Carver, Lakeville, Marion, Middleborough, Rochester, and Wareham in Plymouth County and Acushnet, Freetown, and New Bedford in Bristol County.
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In addition to those at critical risk, the DPH determined 15 communities in southeastern Massachusetts are at high risk for the EEE virus and 18 more are at moderate risk.
“Today’s news is evidence of the significant risk from EEE and we are asking residents to take this risk very seriously,” Public Health Commissioner Monica Bharel, MD, MPH, said in a statement. “We will continue to monitor this situation and the impacted communities.”
This week, the DPH and the Massachusetts Department of Agricultural Resources (MDAR) announced they would be conducting and monitoring aerial spraying in specific areas of Bristol and Plymouth counties to reduce the mosquito population and public health risk.
Aerial spraying began Thursday and is expected to continue throughout the weekend during evening and overnight hours.
While aerial spraying reduces the risk for EEE, it doesn't eliminate it completely, according to health officials.
People also have an important role to play in protecting themselves from the illnesses caused by mosquitoes, the DPH says. They urge residents to avoid mosquito bites, mosquito proof their homes, and protect their pets
The EEE virus has been found in 227 mosquito samples this year, many of them from species of mosquitoes capable of spreading the virus to people.
EEE is a rare but serious and potentially fatal disease that can affect people of all ages. Symptoms can include fever, headache, stiff neck and sore throat.
The most recent outbreak periods in Massachusetts occurred from 2004-2006 and 2010-2012. There were 22 human cases of EEE infection during those two time periods with 14 cases occurring among residents of Bristol and Plymouth Counties.