The Oneida County (N.Y.) Health Department reported Sept. 6 that a horse in the north Rome/Lee Center that was euthanized last week after developing neurologic clinical signs tested positive for Eastern equine encephalitis (EEE). Two previous confirmed cases of EEE occurred in the Town of Westmoreland and in Camden.

This brings the total number of confirmed EEE cases in Oneida County this year to three, with results on two more suspected equine cases still pending, health department officials said. The virus, which is transmitted to horses through mosquito bite and affects the central nervous system, is fatal to horses in 75-95% of the cases. The course of EEE can be swift, with death occurring two to three days after onset of clinical signs despite intensive care. Horses that survive might have long-lasting impairments and neurologic problems.

Clinical signs for EEE include moderate to high fever, depression, lack of appetite, cranial nerve deficits (facial paralysis, tongue weakness, difficulty swallowing), behavioral changes (aggression, self-mutilation, or drowsiness), gait abnormalities, or severe central nervous system signs, such as head-pressing, circling, blindness, and seizures.

The American Association of Equine Practitioners recommends horses be vaccinated for EEE annually