Texas Horse Euthanized After Positive EIA Test
A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. | Alexandra Beckstett/The Horse
Texas Animal Health Commission (TAHC) officials have confirmed a Denton County premises as under official quarantine following a positive test for equine infectious anemia (EIA) in a Quarter Horse there. The affected horse was euthanized.

The premises will remain under quarantine until TAHC requirements are met, and TAHC staff members continue to work with local veterinarians and horse owners to monitor horses that were exposed and to institute biosecurity protocols.

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.