10/29/2026
Most equine owners know a negative Coggins test is needed to cross state lines, enter a competition, or board at a barn. But what does “negative Coggins” actually mean? 🐴
A Coggins is a blood test, performed only by USDA-approved laboratories, that checks for antibodies to Equine Infectious Anemia (EIA). EIA is a potentially fatal, blood-borne viral disease that causes persistent infection in equids nearly worldwide. It is most commonly spread through contaminated needles, syringes, surgical instruments, dental equipment, and blood transfusions, and it can also be transmitted by biting flies.
⚠️ Clinical signs can range from acute illness to no apparent signs at all, but the infection never goes away. Once a horse tests positive, it is a lifelong source of transmission. With no vaccine or treatment available, owners can only choose between lifelong quarantine and humane euthanasia to prevent outbreaks.
Learn more about EIA:
🔗 AAEP: Equine Infectious Anemia (EIA) Disease Guidelines – AAEP
🔗 Equine Disease Communication Center: https://www.equinediseasecc.org/equine-infectious-anemia
