Equine Infectious Anemia
Equine Infectious Anemia (EIA) is a viral disease for which there is no vaccine and no cure. Though most horses succumb rapidly to EIA, a percentage of infected horses appear to recover. It is because of these healthy appearing carriers that we test horses. It insures that we do not put their pasture mates at risk.
The EIA disease is spread by horseflies. The large horsefly is the main vector. If they bite an infected horse and then bite a healthy horse, the disease gets transmitted. The virus does not live for very long on the horsefly, maybe as little as fifteen or thirty minutes. So for one horse to infect another they must be close to each other. The EIA disease occurs anywhere horseflies live.
To insure that an animal is not harboring the virus, a simple blood test is performed. The EIA (or "Coggin's") test checks for Equine Infectious Anemia (EIA) antibodies in the horse's blood. Blood samples must be sent to a state approved laboratory for testing. This test is often required for you to take your horse to a show or whenever you transport your horse across a state line. It is to prove to others your horse is safe to be around other horses. Some states now require a negative Coggin's test on a horse before he can be sold.
Once your horse is tested negative for EIA, (s)he will be issued a government certificate stating that (s)he is free from the EIA virus and further testing is not required for your own peace of mind. You may be required to have a test done yearly to show or transport your horse, so other people will know your horse is free from this disease.
New England Horse Labs uses the ELISA method as opposed to the older, subjective AGID method. The SA-ELISA II test utilizes a synthetic envelope antigen and a recominant core antigen in an enzyme-linked immunosorbent assay (ELISA) for the qualitative determination of antibodies to Equine Infectious Anemia Virus (EIAV) in horse serum.