A fifth person has been confirmed to have the rare and potentially deadly eastern equine encephalitis, or EEE, virus in Massachusetts this summer, state health officials said Thursday.
The latest human case is in a man in his 70s from southwestern Middlesex County, according to the Massachusetts Department of Public Health's release.
Three more communities have had their EEE risk raised to critical: Ashland, Hopedale and Milford. There are now 32 at critical risk throughout the state.
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This summer's EEE outbreak has prompted massive spraying operations from the air and the ground to try to limit mosquito populations and, therefore, mitigate the risk of EEE, which is trasmitted by the insects.
"Even as the weather begins to cool, it remains critically important that people take steps to protect themselves and their families from mosquito bites," Public Health Commissioner Monica Bharel said in a statement.
Four other people across Massachusetts have been diagnosed with EEE this summer, according to the Massachusetts Department of Health. The family of one woman said she died after being diagnosed, though health officials haven't confirmed that.
EEE affects the nervous system and kills about 1 in 3 people who contract it, according to the U.S. Centers for Disease Control and Prevention.
To protect against EEE, use bug spray, wear long sleeves and pants outdoors and avoid activities in the evening and early morning, when mosquitoes are most active, health officials say.
Before this year, the last EEE outbreak in Massachusetts was between 2010 and 2012.