In many horses, the first or only sign of EHV-1 infection is fever, which can go undetected. | Photo: The Horse Staff

Veterinarians have diagnosed a Montgomery County, Texas, Quarter Horse with equine herpes myeloencephalopathy (EHM), the neurologic disease linked to equine herpesvirus (EHV-1), on April 9, the Texas Animal Health Commission (TAHC) reported April 10.

The positive horse attended a reining event in Ardmore, Oklahoma, the week of March 18. Staff from the TAHC has been in contact with the Oklahoma state veterinarian to ensure event participants are notified and enhanced biosecurity measures are taken. Since the Oklahoma event, the horse has not traveled to any other event and is under the care of a Brazos County veterinary hospital. The horse was quarantined after showing signs of ataxia (incoordination) and other neurologic signs consistent with EHM.

While the risk of exposure to the virus was likely low at the event, owners of horses potentially exposed are encouraged to take precautions. Exposed horses should be isolated and have their temperatures monitored twice daily for at least 14 days after last known exposure. If an exposed horse develops a fever or other signs consistent with EHM, a veterinarian should perform diagnostic tests. Owners should work with their veterinary practitioners to establish appropriate monitoring and diagnostic plans for any potentially exposed horse(s)