CHRB Offers EHV-1 Update

The California Horse Racing Board issued the following update Friday evening regarding a recent case of EHV-1 at Los Alamitos:

A 10-year-old horse used to pony horses at Los Alamitos Race Course was euthanized after developing severe neurological signs, subsequently testing positive for the “wild-type” strain of equine herpesvirus type 1 (EHV-1). Even though the pony horse was exhibiting neurological signs, the “wild-type” strain is generally considered less virulent than the neurological strain EHV-1. The pony was used to accompany Quarter Horses at Los Alamitos during the races. He last worked Feb. 11. The barn where the horse was housed is under quarantine, and the six quarter horses he ponied during the races that week are being closely monitored.

The EHV-1 test results were reported Tuesday evening. Dr. Gary Beck, the CHRB official veterinarian at Los Alamitos, has been monitoring the situation since early Wednesday morning, setting up the quarantine conditions, reviewing biosecurity procedures with horsemen, and consulting with the California Department of Food and Agriculture (CDFA) veterinarian assigned to the incident. To date, there is no indication of additional cases, and the most common incubation period after EHV-1 exposure (three to eight days) has passed from when the pony last had direct contact with other horses (all QHs).

There are horses entered to race at Santa Anita that are currently stabled at Los Alamitos. Those horses are being monitored. Horses with no reasonable exposure risk are being allowed to race after being inspected by CHRB veterinarians prior to shipping to Santa Anita.

Any questions should be directed to the official veterinarians and/or Dr. Rick Arthur, the CHRB's equine medical director.

Updates will continue to be posted in the official veterinarians' offices and on the California Department of Food and Agriculture and Equine Disease Communication Center websites.