Encephalitis is a virus disease affecting horses, mules, donkeys and humans. It is usually transmitted by the bite of mosquitoes but possibly by other insects. In horses, the central nervous system is affected, often resulting in high death losses, whereas in humans the infection usually produces a mild to severe respiratory illness.
Signs of encephalitis in horses include a rapid rise in body temperature, up to 106 deg F, with rapid pulse, loss of appetite and depression. The animal displays a "drifting gait." It may hang its head, appear drowsy, press its head against objects and assume a cross-legged stance. Commonly, the animal may circle continuously until prostrated with death occurring in six to eight days.
For suspected cases of encephalitis, contact your local practicing veterinarian, who will draw blood samples in order that the Ohio Department of Health can analyze for this disease. Do not wait until the animal dies before action is taken.
Consult your veterinarian regarding an equine vaccination program for protection against encephalitis.