A 17-year-old Thoroughbred gelding in Los Angeles County, California, has recently been confirmed positive for equine infectious anemia (EIA) and was euthanized.
Forty-three horses on the property that may have been exposed have tested negative for EIA initially and will be under quarantine until they can be retested after 60 days. The California Department of Food and Agriculture is actively monitoring the situation.
EDCC Health Watch is a program by Equine Network that utilizes information from the Equine Disease Communication Center (EDCC) to create and distribute verified equine disease reports. The EDCC is a nonprofit organization supported by industry donations to provide open access to infectious disease information.
About EIA
Equine infectious anemia is a viral disease that affects horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects like horseflies. It can also spread through the use of blood-contaminated instruments or needles.
A Coggins test checks horses’ blood for antibodies that indicate the presence of the EIA virus. Most states in the U.S. require horses to have a negative Coggins test to travel across state lines.
Once a horse is infected with EIA, it remains infected for life and can spread the disease. While not all horses show symptoms, those that do may have:
- Progressive weight loss;
- Muscle weakness;
- Reduced stamina;
- Fever;
- Depression; and
- Anemia.
There is no vaccine or cure for EIA. Infected horses must be euthanized, die, or be placed under strict quarantine (at least 200 yards from healthy horses) for life.

