Horse in Virginia tests positive for Equine Herpesvirus-1

The Virginia Department of Agriculture and Consumer Services said a neurologic horse was admitted to the Virginia Maryland College of Veterinary Medicine Large Animal Hospital in Blacksburg on November 17.

The horse was euthanized on November 18.

Equine Herpesvirus-1 causes Equine Herpes Myeloencephalopathy. 

EHV-1 can cause four manifestations of disease in horses, including neurological form, respiratory disease, abortion, and neonatal death. EHV-1 myeloencephalopathy results from widespread vascular or blood vessel injury after damage to the lining of the blood vessels of the blood-brain barrier. 

Neurologic signs result from inflammation of the blood vessels, blood clots, and death of neurologic tissue. Cases of EHM occur singly or can affect multiple exposed horses. 

In conjunction with the State Veterinarian's Office of the Virginia Department of Agriculture, all exposed horses at the hospital were immediately isolated from the rest of the hospital population with strict biosecurity protocol and placed under quarantine.  All quarantined horses are being monitored twice daily for fever and other clinical signs. The farm where the horse came from has been placed under quarantine as well.

Horses at this farm are also being monitored for fever and clinical signs. The State Veterinarian’s Office has contacted all other horses that may have been secondarily exposed while at the teaching hospital. 

The Equine Disease Communications Center Biosecurity has more information on best practices for disease prevention in horses