This is bad news. This is Equine Herpesvirus - 1, or EHV-1. Most horses have probably been exposed to EHV-1, however, according to one source, when horses are under stress the virus can reactivate and can cause EHM, or Equine Herpesvirus Myeloencephalopathy, a neurological form of the disease. This is the disease that was contracted by two Colorado horses at a National Cutting Horse event in Ogden, UT over Mother's Day weekend. One of those horses has been euthanized. Now the disease has been confirmed in 10 horses in California and 1 horse in Washington. Credible (but not official) reports indicate cases of EHV-1 in Utah, Idaho, Arizona and Western Canada. Considering that 54 horses attended the initial event, the number who have been identified with the disease speaks to the ease of spreading this virus. Currently this appears to be a problem in the western states and Canada, but with the ease of interstate transport the virus could easily and unknowingly be carried to other states and even to other countries.
There is no cure for EHM. Symptoms of EHV-1 can be treated, but once the horse demonstrates neurological complications the only option is euthanasia.
The incubation period for EHV-1 is 2-14 days. The virus is spread in horses from nose-to-nose contact and through water droplets in the air. It can also be carried on grooming and feed equipment and on caretaker's clothing. Humans can not contract the disease. Many equestrian events have been canceled for this weekend and the Colorado State University Vet Hospital has closed its doors to horses coming in or going out. Horses being transported into the state of Colorado need to have a permit number on their health certificates, which is obtained from their veterinarian, who must call the Dept. of Ag in Colorado.
Horses that have had possible contact with the virus should be isolated and precautions taken to avoid spreading the disease to others. There are many excellent resources available on the Internet. One publication is put out by the USDA. It describes EHM and talks about avoiding exposure and monitoring your horse if you think he may have been exposed. It is entitled, "Equine Herpesvirus Myeloencephalopathy, A Guide to Understanding the Neurological Form of EHV Infection"
EHV-1 gives a new meaning to 'Going Viral'. Take care of your horses! Keep on top of the news to keep your guys/gals safe.