The Madera County horse is California’s first confirmed equine infectious anemia case since 2017. | Photo: Wikimedia Commons

On Jan. 24, the California Department of Food and Agriculture (CDFA) confirmed the state’s first case of equine infectious anemia (EIA) since 2017. The affected 24-year-old Paint mare in Madera County had been tested to travel out of state and was euthanized on Jan. 24. No horses on the mare’s premises were exposed; however, officials are performing an epidemiological investigation to determine if any other horses were exposed.

Equine infectious anemia is a viral disease that attacks 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 such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines