On December 15, 2017, the Washington State Department of Agriculture reported equine herpesvirus type 1 (EHV-1) in a 13-year-old Halflinger gelding at one facility in King County, Washington. Officials report that 37 of 60 horses have now been tested, with 16 horses confirmed positive for the EHV-1 neurotropic strain. Seven horses have been euthanized due to equine herpesvirus myeloencepalopathy (EHM).
Clinical signs of the EHM horses included 102-105 degree fevers, hind limb ataxia, no tail tone and dribbling urine. Treatment of horses includes supportive care and anti-viral therapy. The attending veterinarian is making morning and evening rounds at the barn and evaluating fevers and clinical signs.
The horse facility is still under quarantine and strict equine biosecurity in place. At this time no other horse facilities are reporting new cases in the state of Washington.
Pennsylvania EHV-1 Quarantine Released
On Tuesday December 26, 2017, the quarantine put in place in Butler County, Pennsylvania, which arose from an initial EHV-1 quarantine on November 15, 2017, has been revoked by the Pennsylvania Department of Agriculture. This was the index premises, a small dressage barn. One other closely related private barn was also under quarantine, but that quarantine was released on December 6, 2017. No additional cases beyond the index case, which has recovered, were identified during this quarantine.
The Equine Disease Communication Center (EDCC) works to protect horses and the horse industry from the threat of infectious diseases in North America. The communication system is designed to seek and report real time information about disease outbreaks similar to how the Centers for Disease Control and Prevention (CDC) alerts the human population about diseases in people.