San Bernardino County, California
The horse originally resided in San Bernardino County, where investigation revealed 19 exposed horses, six of which were also confirmed positive on Jan. 13. | Photo: Wikimedia Commons

On Jan. 3, California Department of Food and Agriculture (CDFA) confirmed that a 5-year-old Quarter Horse gelding in the racing industry tested positive for equine infectious anemia (EIA) while in Arizona. The horse originally resided in San Bernardino County, where investigation revealed 19 exposed horses, six of which were also confirmed positive on Jan. 13. The rest of the horses on the San Bernardino County premises will remain under official quarantine until they are retested in 60 days.

CDFA continues investigating to find any additional exposed horses.

About EIA

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.

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.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

  • Progressive condition loss;
  • Muscle weakness;
  • Poor stamina;
  • Fever;
  • Depression; and
  • Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.