Horse owners are familiar with a Coggins test—that piece of paper required for entry into most horse shows and sales and/or for interstate horse transport. But many overlook the fact that this piece of paper, which serves as proof that the horses has tested negative for equine infectious anemia (EIA), is essential to protecting the health of the national equine population. A number of recent EIA positives in racing Quarter Horse populations in California and Texas has increased the need for awareness about this potentially fatal blood borne disease of horses, donkeys, and mules.

Also known as swamp fever, EIA is caused by a virus closely related to the human immunodeficiency virus (commonly known as HIV). The equine condition might not cause any outward clinical signs, or they can be apparent, ranging from fever and lethargy to weight loss; anemia; and swelling of the legs, chest, and abdomen.

Natural disease transmission occurs when a deerfly or horsefly bites an infected horse, consumes a blood meal, and transfers the virus to another horse. People can also introduce the virus to a naive horse via the use of infected blood or blood products or through the use of blood-contaminated needles, syringes, surgical instruments, dental equipment, tattooing equipment, or any other equipment. Infected horses become lifelong carriers that pose a risk of infection to other horses. There is no known treatment for EIA. The options for managing an EIA-positive horse are euthanasia or lifelong quarantine of the individual horse at least 200 yards from unaffected horses.

Recently, the California Department of Food and Agriculture’s (CDFA) Animal Health