Equine Infectious Anemia


This article is shared by permission from the Horse Industry Association of Alberta

By Kathleen Winfield

You might have noticed that equine competitions and events are now beginning to request a negative result Coggins test as part of their requirements for entry in to the competition or event.  If you frequently travel across international borders with equines, you already know that a negative Coggins is required: but do you know why? So – what is a Coggins test and what is it testing for?

Coggins.test_.closeupA Coggins test is a blood test designed to determine if antibodies are present for the viral disease Equine Infectious Anemia (EIA).  A negative result means no antibodies are detected. Blood samples are taken by an accredited veterinarian and the test performed in an accredited laboratory (accreditation by the Canadian Food Inspection Agency (CFIA)).

EIA is a persistent and incurable viral disease that attacks the equine immune system, including donkeys and mules. Symptoms of infected equines are highly variable and can resemble other diseases so diagnosis can be difficult without doing the blood test.  Symptoms may include anorexia, fever, depression, small hemorrhages in mucous membranes, swelling of legs, lower chest and abdomen, fatigue, reduced stamina or weakness, rapid breathing and rapid weight loss, jaundice. An infected equine might only exhibit a loss of coordination.  It is also possible that an equine may be a carrier of the disease but not show any symptoms. All horse owners should be aware of EIA, but not alarmed, as the prevalence has remained relatively low in western Canada.

This disease is transmitted by contaminated blood or blood products.  Biting insects such as deer and horse flies are known transmitters of the disease.  This transfer is strictly “mechanical” which means the virus does not replicate itself in the insect – it is contained in the blood from the infected equine that the insect carries on its mouthparts then deposits into the bloodstream of the next equine during the next bite.   The virus only survives a short time on the insects so the disease is generally spread between horses in close proximity.  As these insects thrive in wet areas, outbreaks of EIA have often been linked to horses pastured in swampy areas (thus the nickname of Swamp Fever for this disease).

There is no cure for EIA and equines infected with the EIA virus carry it for life.  There is no vaccine available. EIA transcends all equines regardless of breed, discipline, training, or husbandry so prevention is the key to managing this disease.  The introduction of Coggins testing, in 1970, has made a significant improvement in managing the disease by identifying infected horses and taking the appropriate actions to prevent exposure to the equine population. In 2015, there have been 10 positive results in Alberta, according to the Canadian Food Inspection Agency (CFIA) report as of 2015-05-31.  Positive cases were reported in the following counties: Grande Prairie No.1 – 1 case, Ponoka No.3 – 1 case, Rocky View No. 44 – 1 case, Pincher Creek No. 9 – 7 cases.

This disease, found around the world and been present in Canada since the 1800s, has been a reportable disease since 1971 and we have had a national policy since 1972. In Canada, as defined by the Health of Animals Act, CFIA must be notified then a protocol of action is initiated.  This involves an investigation of the infected horse and any horses that have been exposed in the previous 30 days as well as destruction or lifelong quarantine of the infected animal.  The current protocol is currently being revised and a new policy will be released by CIFA upon completion.

The Alberta Veterinary Medical Association (ABVMA) suggests the follow guidelines to help control this disease:

• Test all horses for EIA annually. Horses at greater risk should be tested every 4-6 months. Control of EIA is based on voluntary testing, identifying infected equines and removal of infected animals from the general population.
• Farm owners and operators should require and verify a current negative Coggins certificate before introducing any new horses to the farm or ranch.
• Quarantine new horses for 45 days and observe them for any signs of illness before introducing them to the herd. Retest them if EIA exposure is suspected.
• Horse show and event managers should require and verify negative Coggins certificates for all horses entering the premises.
• Use only one disposable needle or syringe per horse when administering vaccines or medications.
• Sterilize dental tools before using them on another horse.
• Keep all stable areas clean, dry and waste-free. Practice good pasture management techniques such as removing manure and providing adequate drainage to discourage breeding sites for pests.

This disease is deadly.  Good management practices on your part as a horse owner will help fight this disease.  In addition to the recommendations by the ABVMA, the CFIA suggests your management practices should include:

• Do not breed EIA-positive equines
• Abide by the national EIA control program
• Consult with your veterinarian if you suspect your equine may be infected with EIA

EIA is a serious concern for all equine owners – we must be vigilant in insuring this disease does not reside in our equine population. In the interest of continuing international trade and travel for equines to and from Canada, it important that the horse industry is proactive about EIA testing. By following the guidelines, we can protect our equines from exposure and continue to enjoy their company for many years to come.

Kathleen Winfield is a EC Driving Coach, CAA Instructor and a Lifelong Horsey Person.