11/21/2025
The Kentucky Department of Agriculture (KDA) / Office of State Veterinarian (OSV) has received notification regarding the confirmation of several cases of equine herpes myeloencephalopathy (EHM), the neurologic disease linked to equine herpes virus (EHV-1) in both Texas and Oklahoma.
The affected horses both attended the 2025 Women’s Professional Rodeo Association (WPRA) World Finals and Elite Barrel Race event in Waco, Texas, Nov. 5-9, 2025. The initial EHV-1/EHM horse was detected several days after the WPRA event finished. The second EHV-1/EHM confirmation occurred at an Oklahoma horse event Nov. 18, 2025. Additional participants of these events have been notified by animal health officials and are being monitored. Kentucky horses were reported to have attended one or both events but currently there are no known EHV-1/EHM detections in the Commonwealth associated with these events. WPRA has listed cancelled events and other updates related to this outbreak.
The extent of this EHV-1 outbreak is not fully known. Presentation of EHV-1 in these horses has been acute with rapid progression and high clinical severity. Measures to prevent further horses from direct or indirect EHV-1 virus contact are recommended. These measures, including increased biosecurity overall, are encouraged.
Mitigating risk of disease introduction is a shared responsibility that requires commitment from exhibitors, trainers, event managers, facility operators, veterinarians, and animal health officials. KDA/OSV encourages event sponsors of high-risk horse population (barrel/rodeo horses) related events to take all necessary precautions to prevent further spread of this virus and protect equine health. Precautions include canceling or postponing equine events utilizing high risk equine populations (rodeo/barrel horses) as the best method to protect horses from further exposure until such time as the extent of the current outbreak has been determined.
Equine owners, handlers, and veterinarian practitioners are encouraged to take the following precautions:
Isolate the horses that attended the event for at least two (2) weeks.
Have the temperature of returning horses monitored twice daily for at least 14 days after last known exposure. If a fever (>102.5°F) or other signs consistent with EHM develop, a veterinarian should initiate testing.
Suspend hauling, showing, or mixing horses from the exposure group until further notice. Avoid taking exposed horses to other barns or events.
Disinfect boots, trailers, wash-racks, cross-ties, tie-areas, tack and tack rooms, buckets, grooming tools, and any shared equipment. Use an appropriate virucidal disinfectant.
Avoid sharing tack, halters, grooming equipment, buckets, water hoses, etc., between exposed and unexposed horses.
When doing feeding and chores, work with the returning horses last, wear boots and coveralls, and remove them before working with other horses.
If any horse exhibits neurologic signs, coughing, or nasal discharge, isolate it immediately, wear protective gear, and call the veterinarian.
Keep accurate records: track which horses were present at events, their movement, and who handled them for contact tracing if needed.
Stay in contact with the veterinarian and keep up to date on updates from state veterinary authorities.
Have laboratory samples for clinical horses submitted to an American Association of Veterinary Laboratory Diagnosticians (AAVLD) accredited laboratory. (e.g. University of Kentucky Diagnostic Laboratory (UKVDL) or Murray State University - Breathitt Veterinary Center (MSU BVC) Laboratory).
Wash your hands.
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 pe**le paralysis. It is important to remember these signs are not specific to EHM and diagnostic testing is required to confirm infection.
Additional resources can be found here:
USDA APHIS Equine Herpes Myeloencephalopathy Fact Brochure
AAEP Equine Biosecurity
