Two Horses Test Positive for EIA in Montana

Because two horses recently tested positive for equine infectious anemia (EIA) in Montana, the Montana Department of Livestock's Animal Health Division has scheduled a May 17 meeting in Gallatin county to update local horse owners on the situation.

EIA, also called swamp fever, was reported in Gallatin county April 26 after a horse tested positive following a routine Coggins test.

"The horse was going to be traveling out of state, which is how the positive came up," said Tahnee Szymanski, DVM, a staff veterinarian for the Department of Livestock. "As a result of the positive test, two more horses on the premises were tested, and we found one other positive."

Fifty nearby horses were also tested. As of May 13, about 45 of those tests had come back, all negative, said Szymanski. She expected the rest of the test results in the next day or so.

Because of the infectious nature of EIA, horses testing positive must be euthanized or quarantined for life. The two positive horses were quarantined for transport to an EIA-positive herd. Szymanski explained that these herds are bled monthly for lab efficiency testing.

"In that way, these animals can contribute to our understanding of the disease and they do not have to be euthanized," she said.

EIA is spread by biting insects and through contaminated needles, said Szymanski.

"We recommend annual testing and like to see horses that travel for equine-related events tested twice a year," she said. "While Coggins tests are routinely required for horses traveling out of state, some boarding facilities, and events now require negative Coggins tests as well. Some farms also require a negative test to bring an animal in for breeding."

The May 17 meeting will be held at 10 a.m. at the Gallatin County Fairgrounds, building #4.

This was the first known case of EIA in Montana since 2007.

About the Author

Tracy Gantz

Tracy Gantz is a freelance writer based in Southern California. She is the Southern California correspondent for The Blood-Horse and a regular contributor to Paint Horse Journal, Paint Racing News, and Appaloosa Journal.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More

Free Newsletters

Sign up for the latest in:

From our partners