Equine Herpesvirus Myeloencephalopathy Confirmed in Virginia

Detection of a neurological illness in Virginia thought to be equine herpesvirus-1 (EHV-1) myeloencephalopathy was recently confirmed as such at several laboratories throughout the United States.

The organism causing EHV-1 can cause three different forms of the disease--rhinopneumonitis, a respiratory disease of mostly young horses; abortions in pregnant mares; and this neurologic disease. There are at least seven other strains of equine herpesviruses, named in order of their discovery. (See Article Quick Find #32 at www.TheHorse.com for more on herpesviruses.) 

Four horses at Fox Chase Farm in Middleburg, Va., displayed the mysterious symptoms of the neurological form of EHV-1 in late April. Three of the horses were euthanized and one pony recovered with supportive care. (See Article Quick Find #3585 at www.TheHorse.com). 

Joseph P. Garvin, DVM, is the laboratory director of the Virginia Department of Agriculture and Consumer Services' Warrenton Regional Animal Health Laboratory, where the autopsies of the second and third horses were performed. "No more cases surfaced--only the ones at the original premise," said Garvin. "It's still not known where it came from. It could have come from any number of places."

Garvin's Warrenton, Va.-based laboratory personnel performed necropsies on two of the affected horses and sent tissue from the horses to various facilities with the ability to test for EHV. The first confirmation of EHV-1 that Garvin received was from the University of Kentucky's Gluck Equine Research Center. The treating practitioner had sent whole blood from one of the affected horses prior to its death to the Lexington, Ky. research laboratory for isolation of the virus. 

The United States Department of Agriculture's Animal and Plant Health Inspection Service scientists isolated the virus from the brain of that horse at the Ames, Iowa National Veterinary Services Laboratory. Additionally, Michigan State University received spinal cord tissue from both of the horses for polymerase chain reaction tests, which detected the DNA of EHV within the tissue.

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from TheHorse.com. Learn More

Free Newsletters

Sign up for the latest in:

From our partners