BOSTON (AP) — Massachusetts health officials say a new case of Eastern equine encephalitis has been found in a horse in Middleborough, and are urging people to continue precautions against mosquitoes.

The Department of Health said Friday it is raising the threat level to “critical” in Middleborough and “high” in nearby Plymouth, meaning people should cancel outdoor evening events there until the end of mosquito season. It’s the fourth EEE-infected horse in the state this summer.

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Officials also said the first West Nile virus case has been found in a horse in Dartmouth, which already is at “moderate” risk from mosquitoes.

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EEE has also been found in horses in Tyngsborough and Belchertown this summer.

There have been three human cases of West Nile. A Weymouth woman who died in August is the only human EEE case.

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