Horses from across the West were exposed to a deadly new form of Equine Herpes Virus at a Utah horse show. Equine Herpes Myeloencephalopathy (EHM), which is caused by Equine Herpes Virus (EHV-1). The disease, which results in neuorological symptoms, is highly contagious and often fatal.

Equine herpes virus (EHV-1) is a highly contagious disease that is spread through nasal secretions by nose-to-nose contact when horses nuzzle each other, according to Colorado State University's college of veterinary medicine. It is potentially fatal to horses. Horses cannot infect humans, but people can transmit the virus between animals through contaminated tack and clothing. Symptoms of the virus include hind-leg weakness, decreased coordination, nasal discharge and fever. .

Important points that should be remembered and that have occurred with this incident:

  • Horse owners that are considering attending any equine competitive or congregation events are encouraged to contact the event sponsor to see if the event is going to take place at the scheduled time and place. 
  • Signs associated with this disease include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, leaning against a wall or fence to maintain balance, lethargy, and the inability to rise.
    • Horse owners should watch their horses carefully and call their veterinarian immediately if any abnormal signs are observed.
    • Horses that attended the Ogden, UT event or have been in contact with horses that attended the event should be isolated and a minimum of two temperatures taken and recorded per day on each horse.
    • If there is any increase in body temperature or abnormal clinical signs in any of your horses, notify your veterinarian immediately.
  • The veterinary teaching hospitals in Fort Collins, CO (Colorado State University) and Pullman, WA (Washington State University) are not quarantined but under voluntary restriction of equine and camelid patients at this time.
  • There was only one horse euthanized at the event and the horse was diagnosed with a developmental abnormality of the spine. Testing of the cerebrospinal fluid on this patient was negative for EHV-1 agent.
  • This disease is not transmissible to humans or other animals other than equine (horses, mules, burros) or camelid (llamas, alpacas, camels) species.