dr_relling, flickr

 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.

    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.

    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.   (Associated Press)