On Nov. 19, 2025, the Texas Animal Health Commission (TAHC) received confirmation of equine herpes myeloencephalopathy (EHM), the neurologic disease linked to equine herpes virus (EHV-1), in a Texas Quarter Horse on November 18, 2025.

The horse attended the 2025 WPRA World Finals and Elite Barrel Race event in Waco, Texas on November 5-9, 2025. TAHC staff are working closely with event coordinators, equine owners, and veterinarians to respond to the outbreak, take measures to protect equine, and prevent the further spread of the virus. Additional participants of this event have been notified by the TAHC and are currently being monitored under hold orders.

Clinical signs of EHM in horses may include: fever of 102.5°F or greater (fever most often comes before neurologic signs), nasal discharge, lack of coordination, hindquarter weakness, leaning or resting against a fence or wall to maintain balance, lethargy, urine dribbling, head tilt, diminished tail tone, and penile paralysis. Owners of horses that may have been in contact with these horses or exposed to EHM should work with their veterinary practitioner to establish appropriate monitoring and diagnostic plans to take precautions.

The extent of this EHV-1 outbreak is not yet fully known. Presentation of EHV-1 in these horses has been acute with rapid progression and high clinical severity. A concerning number of mortalities in horses suspected to have EHM have been reported. Investigation into the character and epidemiology of this disease event is ongoing but the need for rapid and proactive actions to curb the spread is clear. Measures to prevent contact of horses from exposure to the virus and increased biosecurity overall are recommended.

TAHC encourages event sponsors to take all necessary precautions to prevent further spread of this virus and protect equine health. Given the nature of this virus and routes of transmission, and out of an abundance of caution, TAHC recommends canceling or postponing equine events as the best method to protect horses from further exposure until such time as the extent of the current outbreak has been determined.