As spring arrives, Dustin Oedekoven, DVM, South Dakota state veterinarian, reminds horse owners to take steps to prevent the spread of equine herpesvirus (EHV).

Historically found in South Dakota, EHV is transmitted between horses in close contact. Three forms of the disease are recognized: respiratory, reproductive, and neurologic. The respiratory form is the most common, with clinical signs including coughing, nasal discharge, and a high fever. The reproductive form causes abortion in mares, and the neurologic form can cause neurologic deficits and even death or euthanasia. Once a horse is infected with the neurologic form treatment options limited, but include supportive care, antiviral drugs and anti-inflammatories.

Prevention of EHV begins with a solid biosecurity plan. Horse owners can minimize spread of EHV by implementing a 21-day isolation policy when adding new horses or returning horses to established herds. Buckets and other items used to feed and water horses or groups of horses should be cleaned and disinfected regularly. Horses with fever or recent known exposure should stay at home.

Vaccines effective in preventing respiratory and reproductive EHV are widely available and should be administered as directed by the owner’s veterinarian. Often this means at least twice every year, with horses that travel to events being boostered as often as every three months. Horse owners are encouraged to visit with their veterinarian to determine a vaccination program best suited to their individual needs