Two cases of Equine Herpesvirus Myeloencephalopathy (EHM) have been reported in Washington state connected to the outbreak of EHM that originated at the Women’s Professional Rodeo Association (WPRA) World Finals and Elite Barrel Race event Nov 5-9.
Washington State University is urging horse owners to remain vigilant following a multi-state outbreak of EHM, the neurologic form of Equine Herpesvirus-1 (EHV-1).
The first affected horse tested positive for EHV-1/EHM several days after returning home from the WPRA event. A second confirmed case was identified on November 18 at an Oklahoma horse event. Animal health officials have notified participants from both events, and monitoring is ongoing.
Common signs of EHM include fever (often appearing before neurologic symptoms), recent respiratory illness, acute ataxia or weakness, and urine dribbling. Owners are encouraged to closely monitor their horses and to contact their primary veterinarian immediately if any symptoms arise. Prompt isolation is critical to preventing further spread.
One case has been reported in Colorado and one in New Mexico—both believed to be linked to the Texas event. Additional cases have been confirmed in Texas, Oklahoma, and Louisiana.
For the latest updates, including any future reports in Washington, visit the Washington Department of Agriculture website. Resources on the outbreak are also available on the Equine Disease Detection Center website.
Additionally, the American Association of Equine Practitioners and the Equine Disease Detection Center are in the process of organizing a Horse Owner Education webinar to help educate the public on the current outbreak. This webinar will take place on Nov. 25 at 8 PM ET.