LITTLE ROCK — A virus fatal to horses has been reported in Johnson County and with the horse show season coming to its climax, horse owners need to protect their mounts, Mark Russell, extension equine specialist for the University of Arkansas Division of Agriculture, said Thursday.

The Arkansas Livestock and Poultry Commission reported Wednesday that there were multiple positives in testing for equine infectious anemia, or EIA, in a herd in Clarksville.

"At present, the infection seems to be isolated to the single herd," the commission said. "There has not been any information that warrants canceling horse shows, etc., in Arkansas at the present time."

Arkansas state law requires all equines that live in the state for more than 30 days to be tested for EIA every 12 months — a test known as a Coggins test.

Horse show operators generally require horse owners to show proof of a current negative Coggins test.

With county fairs underway and the State Fair upcoming, many Arkansans are trailering their show horses around the state.

The best way to protect horses is to "get a Coggins test and only go to events where there will be a reliable individual who is a certified EIA verifier at the gate checking Coggins papers," Russell said.

The virus can be transmitted by blood-feeding insects such as horseflies, deerflies and mosquitoes and can also be transmitted by use of non-sterile surgical equipment.

"Controlling flies around the barn and using repellants are an important defense as well," Russell said.

EIA is caused by a retrovirus that induces a long-lasting infection in members of the equine family, including horses, mules, donkeys and zebras.

The disease can appear in three forms:

• Acute, in which animals are obviously very sick and likely to die

• Chronic, in which the animal may suffer intermittent fever, hemorrhaging and become weaker. The episodes of symptoms can vary in severity and can be fatal

• In the "inapparent" form, infected animals may appear normal, but they are carriers of the virus for life.

For information about EIA, contact your veterinarian. The publication, "Equine Infectious Anemia in Arkansas," is available online at: