The two cases of EIA in Colorado horses are “actually very unique cases”

We are learning more about cases of a deadly equine disease in Colorado.

The state veterinarian sheds light on how equine infectious anemia, or EIA, is detected.

According to Dr. Maggie Baldwin, “Most horse owners are probably going to know it when we talk about a Coggins Test. The Coggins Test is the annual test that most horse owners get for their horses, especially prior to moving across state lines. Most events and shows require EIA testing prior to entry, and it’s one of those diseases that, in the United States, broadly, we’ve done a good job with surveillance, and so our cases have been very few and far between, but we do have cases across the U.S. every year. The two cases that we have— and this has been over the last couple of weeks that me and my team have been working on— are actually very unique cases. They are not associated at all, but we got the cases within about three days of each other.”

While the disease can be transmitted by biting insects, like flies, it can also be transmitted through the use of unsanitary equipment.
That is what happened in one of the two Colorado cases.

“This case with this mare that is associated with the clinic in Texas was actually iatrogenic transmission at this clinic. They were not using proper hygiene practices between breeding mares, and so they bred one of the mares that was EIA positive, and then, subsequently, with everything else that they were working on, they inadvertently transmitted EIA to those horses,” Dr. Baldwin adds.

She says that most infected horses can show signs of weakness and weight loss, and they can just seem off.
Both of the infected horses in Colorado were euthanized, and the premises are now under quarantine.

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