AP

September 4, 2020 | 5:28 PM

BOSTON (AP) — Public health officials in Massachusetts on Friday announced the state’s fourth human case of the mosquito-borne disease eastern equine encephalitis this season.

The latest case is a woman in her 60s who was exposed to the disease in Plymouth County, according to a statement from the state Department of Public Health. As a result, the risk level in the town of Plymouth been raised to high.

There are now four communities in the state at critical risk, 10 at high risk, and 18 at moderate risk for the disease that causes brain swelling and is potentially deadly.

Although mosquito populations are declining and most transmission to people occurs before mid-September, the risk will continue until there has been a hard frost.

Residents are urged to take precautions, including using insect repellent while outside, and limiting outdoor activity at dusk to dawn when mosquitoes are most active.

In 2019, there were 12 human cases of the disease in Massachusetts, and six deaths.

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