Officials at the Canadian Animal Heath Surveillance System (CAHSS) have confirmed positive equine infectious anemia (EIA) test results for one horse in St. Paul County and another horse in Saddle Lake in central Alberta. Both horses were tested by the Canadian Food Inspection Agency’s (CFIA) national reference laboratory.

The horse in St. Paul County was confirmed positive on Dec. 3 after the owner requested their veterinarian test due to clinical signs compatible with EIA. The horse was euthanized shortly afterward because its condition rapidly deteriorated. Two other horses on the premises had died previously with similar clinical signs but without being tested for EIA.

The horse in nearby Saddle Lake was confirmed positive on Dec. 10. The affected horse’s owner had requested the test after being made aware that it had commingled with infected animals on the chuckwagon racing circuit last summer; however, no clinical signs of EIA were noted by the testing veterinarian.

CFIA is investigating and other equids on the premises have been officially quarantined until all disease response protocols are complete, including follow-up testing and ordering that confirmed cases be euthanized. Trace-out activities might warrant actions at other premises as well.

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.

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.

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.