State veterinarians have been notified if their jurisdiction received horses that could potentially be spreading equine herpesvirus-1 (EHV-1) from the shipment of 15 horses that included ones responsible for sparking the current outbreak of EHV-1, according to Jim Rogers, media coordinator for the USDA’s Animal and Plant Health Inspection Service (APHIS).

Rogers said that since EHV-1 is not considered a foreign animal disease, it will be up to the individual states to handle the situation.

Fifteen horses imported from Germany were shipped from a New York quarantine facility to various locations across the country. One horse shipped to California died of EHV-1. Five of the 15 were shipped to Florida, where two are showing neurologic signs and three are in isolation.

Three Florida horses that were in contact with the imported horses have died, with EHV-1 confirmed in at least one. Four other horses that were in contact with the imported horses are showing neurologic signs. This number has not changed since Saturday.

The 15 animals were in quarantine at the USDA New York Animal Import Center in Newburgh, N.Y. Rogers said that one horse did have a fever while in quarantine, but the horse improved and was not showing any clinical signs at the time it was released.

Mike Short, DVM, equine programs manager for Florida’s Division of Animal Industry, said today (Dec. 18) there are 19 horses showing suspect clinical signs (fevers of unknown origin) in Wellington. Area veterinarians are working to trace the movement of the affected animals to determine if any in-contact horses are showing clinical signs. The horses with fevers are having samples submitted for EHV-1 testing.

There are no state or federal restrictions for horse movements into, within, or out of Florida, except for the five premises in Wellington with movement restrictions in place.

Because EHV-1 can spread through direct contact or through the air, the disease is a concern where groups of horses congregate. The clinical signs of EHV-1 include fever and nasal discharge, and more rarely, neurologic signs (including an inability to control the hind limbs and tail) and abortions. Scientists definitively diagnose EHV-1 infections on virus culture from blood or nasal secretions, PCR (polymerase chain reaction test, a DNA test of blood or nasal secretions), or serology (blood antibody titers).

For more information on EHV-1, check out our free PDF library of EHV-related articles including images, or all our archived EHV-1 articles on TheHorse.com.