A Norfolk County woman in her 80s has died of Eastern equine encephalitis. She was the first Massachusetts resident this season to be infected with the often lethal mosquito-borne illness, state public health officials announced Tuesday.
The woman, who has not been identified, was hospitalized earlier this month, and died a few days later.
Health officials said they are tracing the woman’s activity in recent weeks to determine where she may have been bitten by an infected mosquito, and will determine whether to increase warning levels and urge cancellation of night-time activities based on their findings.
“We are right in the middle of peak transmission for EEE,’’ said Dr. Catherine Brown, state public health veterinarian. “Given the activity we have seen over the last decade for EEE, I am afraid this is the type of thing we are going to see happen.’’
Eastern equine has been detected in Massachusetts since the 1930s and was once considered rare, with isolated cases occuring years apart. But infections have increased in recent years, and last season, with seven people infected, was unprecedented. Three of those infected last year died.