The Virginia Department of Agriculture and Consumer Services (VDACS) has confirmed a second diagnosis of equine herpesvirus myeloencephalopathy (EHM) at the affected farm in central Virginia.

On Feb. 1, a horse-boarding stable in Chesterfield County was placed under quarantine after a horse with fever and neurologic signs tested positive to the equine herpesvirus-1 (EHV), the virus that causes EHM.

Since that time, nine horses in the stable have developed fevers, but none exhibited neurologic signs. Veterinarians tested three of these horses for EHV and one tested positive. Testing for the remainder of the febrile horses will continue over the next several days. The facility will remain under quarantine for 21 days past the last positive finding of EHV.

The febrile horses have been isolated on the farm and are under veterinary care. The stable transferred four of these horses to the isolation unit at Marion Dupont Scott Equine Medical Center, in Leesburg, for additional care and monitoring. Because these horses were admitted under the established isolation protocol, the Equine Medical Center is not under quarantine and is admitting and treating patients normally. Neither the Chesterfield stable nor the equine medical facility poses a risk to the Virginia horse population