A second human case of the rare, mosquito-borne Eastern Equine Encephalitis (EEE) virus has been recorded in Massachusetts this season, state public health officials announced Saturday.
Laboratory testing confirmed a woman in her 60s contracted the virus after being exposed in Hampden County, the Department of Public Health said in a statement.
The positive diagnosis prompted the department to raise the EEE risk level in Wilbraham to critical and in Hampden and Monson to high, officials said. Chicopee, East Longmeadow, Ludlow, Palmer, and Springfield are all now at moderate risk for the virus.
A potentially fatal infection, EEE triggers brain swelling, fever, and coma, and kills approximately one-third of the people who contract it. Those who survive are often left with severe neurological disabilities and complications. The illness has no cure.
Last week, officials confirmed the first human case of EEE this year after a boy under the age of 18 in Plymouth County first started to show symptoms on July 20.
State leaders have continually urged the public to take precautions to minimize risk of mosquito bites as Massachusetts weathers what is expected to be a busy year for the virus.
In 2019, the Bay State saw its most active EEE season since the 1950s, signaling the start of an outbreak that could potentially last through next year. Twelve human cases were reported, and six people died from EEE last year.
As of Saturday, three municipalities were considered at critical risk of the virus, while eight others and 20 more were at high and moderate risk, respectively, officials said.
“All residents are reminded to use mosquito repellent any time they are outside, and those in high and critical risk communities are advised to schedule their outdoor activity to avoid the dusk to dawn hours to reduce exposure to the mosquitoes most likely to spread EEE,” the DPH said in a statement.
So far this year, the Department of Public Health has found EEE in 65 mosquito samples, with over 70 percent of them in species capable of infecting humans.
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