June 7, 2011
Equine Herpes Virus (EHV-1) — an Update
by Cindy Reich
The number of new EHV-1 cases appears to be slowing down; however, horse owners should continue to be vigilant and take precautions to minimize any chance of exposure to their horses.
In Colorado, one of the most heavily affected states, Colorado State University announced on June 1 that they are reopening their Veterinary Teaching Hospital, which had been closed to all but emergency patients since May 17. However, they are going to continue to use stringent biosecurity measures and require a travel and exposure history from all horses coming to the facility.
The USDA released its latest incident report today, which indicated that there 421 horses that were exposed to the virus by attending the show in Ogden, Utah, with 40 horses that are suspected to have the virus as of today’s report, but are not yet confirmed; 32 horses have been confirmed to have EHV-1. There have been an additional 26 horses confirmed to have EHM (equine herpesvirus myeloencephalopathy) the neurologic form of EHV-1, with 6 horses suspected to have EHM, but not confirmed. Ten horses have been euthanized.
There are 1,672 horses considered to be exposed by secondary (came in contact with or were exposed to a horse at the Ogden event) or tertiary contact (at least three degrees of separation from a horse that attended the event) from reporting states. There are 24 suspected cases of EHV-1 and 20 confirmed as well as four suspect cases of EHM and six confirmed cases of EHM, with two horses having been euthanized.
Out of 61 facilities that have confirmed or suspected cases of EHV-1, there have been two new facilities reporting suspected or confirmed cases as of June 1. Therefore, while the number of new cases has decreased, it has not stopped.
Therefore, in summary: 84 confirmed EHV-1 or EHM cases have been reported in 10 states: Arizona, California, Colorado, Idaho, New Mexico, Nevada, Oklahoma, Oregon, Utah, and Washington. Fifty-eight of those cases are horses that were at the Ogden event. Twelve horses are dead or have been euthanized. Two new facilities have suspected or confirmed cases.
The best way to protect your horse is not to bring it into contact with any new horses or facilities that have a lot of horse traffic. The first sign of the disease is a spike in the horse’s temperature, so taking your horse's temperature two times a day is a good management practice. If you are considering taking your horse to a show or event, some show facilities are now requiring that the horse’s temperature be taken two times a day and posted on the stall for inspectors to check. If your horse has a sudden rise in temperature, you should contact your veterinarian immediately. Signs of EHV-1 include lethargy, nasal discharge, high temperature, hind-end weakness, uncoordination, inability to rise, or leaning against a wall or fence for balance.
For more information: http://www.aaep.org/EHV_resourcesowner.htm
