Recent cases could be warning signs.

Two recent cases of Equine Herpes Virus (EHV-1) could be warning signs to horse owners, event managers and veterinarians.

The nearest case was found in Kansas following a barrel racing event in Lincoln, Neb. As soon as symptoms were displayed, the horse’s health deteriorated and it died shortly after.


According to Oklahoma State University report ‘Oklahoma Horse Industry Trends’ by OSU extension equine specialist David W. Freeman, in 2005 the American Horse Council (AHC) estimated there to be around 326,000 head of horses in Oklahoma.


“Oklahoma ranks first in number of horses per capita,” Freeman said in his report.


There have been no related EHV-1 cases in Oklahoma, but the report said that as of 2007 Oklahoma’s four sanctioned pari-mutuel racetracks conduct over 198,000 official multi-state races.


Although Kansas is a state away, this many out-of-state equine interacting with Oklahoma horses makes the EHV-1 case cause for concern.


“The virus isn’t new,” Doctor of Veterinary Medicine in Tecumseh, Gary Lenaburg, said. “There is always cause for concern, but it hasn’t proven itself to be epidemic in nature in the past.”


Varying factors can cause the virus.


“For disease to occur, one of two things must occur,” Lenaburg said. “Either an individual is exposed to a high dose of the virus directly, or its immune system is repressed to the point that it is more susceptible to infection.”


Lenaburg said that horse owners should practice basic precautions and common sense.


“Any time a horse goes to an event, there is stress involved,” He said. “Before attending an event, ensure that your horse is healthy, displaying a normal temperature of 100.5 degrees.”


Besides only socializing horses with good immune systems, horse owners should make sure to only attend reputable events, Lenaburg said.


Other precautions can be taken in addition to practicing common sense.


“The best thing to do is to give them the EHV-1 vaccine, which is used to cause abortion in mares,” Lenaburg said. “If the horse is going to events, give them a dose of the EHV-1 vaccine. It’s not considered protective, but it’s what we have.”


Lenaburg said horse owners with healthy animals should keep in mind that the virus is not new, and that horses can carry the dormant virus for many years before it is activated by stress.

The Oklahoma Department of Agriculture, Food, and Forestry (ODAFF) specified measures that can be taken to avoid the spread of communicable equine diseases.


Horse owners and event managers should maintain awareness, implement biosecurity practices to minimize potential exposure, keep up to date on vaccines and report suspicious symptoms.