The 21-year-old crossbred gelding resided at a Loudoun County boarding stable, which is under quarantine. | Photo: Wikimedia Commons

The 21-year-old crossbred gelding had experienced clinical signs of ataxia (incoordination) and recumbency (inability to stand). He resided at a Loudoun County boarding stable, which is under quarantine. Although two Maryland horses were exposed, no horses on the Loudoun County farm have shown any clinical signs or fever since the quarantine began on Oct. 24. Virginia officials notified the Maryland state veterinarian’s office, which is following up on the exposed horses.

EHV 101

Equine herpesvirus is highly contagious among horses and can cause a variety of ailments in equids, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and equine herpesvirus myeloencephalopathy (EHM, the neurologic form).

In many horses, the first or only sign of EHV-1 infection is fever, which can go undetected. In addition to fever, other common signs of EHV-1 infection in young horses include cough, decreased appetite, depression, and a nasal discharge. Pregnant mares typically show no signs of infection before they abort, and abortions usually occur late in gestation (around eight months) but can be earlier. Abortions can occur anywhere from two weeks to several months following infection with EHV-1