What Horse Owners Should Know About EHV1 Outbreak Risks

The North Dakota Department of Agriculture announced that the State Veterinarian’s Office has been made aware of an outbreak of Equine Herpesvirus-1 (EHV-1) and its neurologic form, Equine Herpesvirus Myeloencephalopathy (EHM), in horses associated with barrel racing and rodeo events in Texas and Oklahoma. Several confirmed cases of EHM have been reported in both states, with additional cases and equine deaths under investigation.

There are currently no confirmed cases of EHV-1 or EHM in North Dakota, but the State Veterinarian’s Office is actively coordinating with Texas and Oklahoma officials to monitor the situation. Trace information has been received from the affected states, and North Dakota horse owners who may be at risk will be contacted directly. Quarantines will be issued to mitigate further spread of the disease.

“This outbreak serves as a reminder of the potential disease risks associated with large commingling equine events,” said State Veterinarian Dr. Ethan Andress. “It underscores the importance of timely reporting of diseases and ensuring that movement requirements are followed, including veterinary inspection and health certificates prior to travel.”

EHV-1 can spread through direct contact between horses, the air, and contaminated equipment, clothing, or hands. To reduce the risk of transmission, biosecurity measures should be taken, including avoiding shared food or water containers and preventing nose-to-nose contact.

Equines entering North Dakota for any duration must be accompanied by a certificate of veterinary inspection.

“If your horses traveled to Texas, Oklahoma, or other equine events where EHV-1 exposure may have occurred, please contact our office directly,” Andress said. “We will provide guidance regarding isolation and monitoring. Prevention starts by keeping sick animals at home and being aware of the risk factors while traveling and competing.”

EHV-1 can cause a range of symptoms, including respiratory disease, abortion, neonatal death, and sometimes the neurologic form of the disease, EHM. While current vaccines for EHV-1 can reduce viral shedding, they do not provide protection against EHM.

“These incidents serve as a reminder to work with your local veterinarian on preventive programs for all species,” said Agriculture Commissioner Doug Goehring.

Though EHV-1 is highly contagious among horses, it poses no threat to human health.