In many horses, the first or only sign of EHV-1 infection is fever, which can go undetected. | Photo: Stephanie L. Church/The Horse

On June 16, the Virginia Department of Agriculture and Consumer Services (VDACS) confirmed a Fauquier County horse with the neurologic form of equine herpesvirus-1 (EHV-1). The 26-year-old Warmblood mare, who is reported as vaccinated, began experiencing clinical signs on June 12. These included fever, recumbency (inability to rise), and neurologic signs. She was subsequently euthanized. Six other horses were reported as having been exposed.

EHV 101

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 myeloencephalitis (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