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.

Related Stories
Expanded school access to whole milk provides modest but reliable demand support for U.S. dairy producers.
Alissa White with American Farmland Trust joined us to provide insight into climate resilience efforts and strategies to help farmers manage weather-related risks.
University of Nebraska President Dr. Jeffrey Gold joined us to share practical health and safety guidance for managing respiratory and skin health during the winter season.
Roger McEowen with the Washburn University School of Law joined us to provide legal analysis on key cases shaping the agricultural landscape heading into the year ahead.
NASDA declared 2026 the International Year of the Woman Farmer. President Amanda Beal joins us to share NASDA’s new hub, which highlights the impact of women in agriculture worldwide.
The American Farm Bureau Federation’s 2026 agenda centers on labor stability, biosecurity, and economic resilience for family farms. Expanded DMC coverage improves risk protection for dairy operations facing tighter margins.