Feed is not on the list of common transmission sources for the the dangerous herpes virus that has killed horses in several states in the West and Midwest.


Instead, the Equine herpes virus, which is said to be a common virus of horses worldwide, is spread by horses breathing upon one another and other close contact including shared tack and human handling.

Horses from Colorado and California that competed in the National Cutting Horse Association’s Western National Championships in Ogden, Utah were among those stroked with the virus.

The potentially deadly horse virus can cause respiratory and neurologic diseases, and abortions.

The University of California (UC)’s Veterinary Medical Teaching Hospital at Davis has issued guidelines for minimizing the risk of transmitting the horse virus.  It suggests:

— Restrict movement of horses from the premises.

— Physically isolate exposed horses a minimum of 30 feet away from other horses for 21 days.

– Horses that are new to premises should also be isolated.

If you suspect a horse may have been exposed, then monitor the horse’s rectal temperature twice a day for 14 days and call your veterinarian immediately if a fever develops (≥ 102 ºF).

Use protective barrier clothing that can be changed in between horses when handling isolated or quarantined horses. Protective barrier clothing includes: gloves, disinfectant foot baths with impervious foot covers, and coveralls or protective gowns. Hands should be washed with soap and water or alcohol based hand sanitizers (if visibly soiled, hands must be washed with soap first) after handling each horse in quarantine.

Provide separate equipment for each horse and do not share buckets, feeders, tack, grooming equipment, towels etc among horses.  

When filling water buckets, make sure the end of the hose does not touch the water in the bucket in order to avoid contamination with infectious material that may be on the outside of the hose.

Potential inanimate fomites such as buckets or tack, if used on more than one horse, should be disinfected before use on another horse. Note: The equine herpes virus is susceptible to many disinfectants; however, whenever organic matter is present, washing and removal of organic material should be done first. If organic matter persists, use disinfectants suitable for use in the presence of organic matter, such as higher peroxygen compounds (e.g.-Trifectant, Virkon) or phenolics (e.g.-Tek-Trol or 1-Stroke Environ).

Consider vaccinating at risk healthy, afebrile horses on the premises to which exposed horses are returning. Consult a veterinarian. 

“We urge horse owners and coordinators of upcoming equine events to educate themselves on the virus and to exercise the utmost caution as they determine whether to participate in or host events that could increase their animals’ exposure to this potentially life-threatening

disease,” said David Wilson, an equine veterinarian and director of UC Davis’ William R. Pritchard Veterinary Medical Teaching Hospital.

“We encourage owners to avoid any non-essential transport of their horses, mules and donkeys,” said Gary Magdesian, an equine veterinarian at UC Davis.

He added that alpacas, llamas and other camelid species are rarely affected by equine herpes virus.