EEE: Two Ohio Horses Dead, First Ohio Case in 19 Years

The Ohio Department of Agriculture confirmed cases of Eastern Equine Encephalitis (EEE) in two horses that died on a farm in Mercer County. This is the first incident of EEE in Ohio since an outbreak in 1991 in Wayne and Holmes counties. At this time, there are no known human illnesses associated with this confirmation.

Eastern Equine Encephalitis is caused by a virus that can infect birds, horses and humans. It is transmitted by mosquitoes, and outbreaks typically occur in late summer and early fall when mosquitoes are most abundant. Infected horses could experience symptoms including paralysis, impaired vision, difficulty swallowing, hanging their heads and grinding their teeth.

An effective equine vaccine exists for EEE. Typically, infected horses with clinical symptoms die within three to five days after onset of clinical signs. There is no treatment for EEE aside from supportive care.

EEE infection is rare in humans, but when it does occur, it can be serious. The Ohio Department of Health urges Ohioans to take steps to avoid mosquito bites, such as wearing light-colored long pants and long-sleeved shirts as well as socks and shoes.

In addition, to avoid mosquito bites for both animals and humans, the Ohio Departments of Agriculture and Health recommend insect repellants be used according to label directions. Mosquitoes can be active until the first frost and will stay infected, and capable of transmitting viruses, as long as they live.

Suspect equine cases should be reported to local veterinarians and the Ohio Department of Agriculture, and any suspect human cases should be reported to the local health department.

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