Q: What is a coggins test?
A: The coggins test is an agar gel immunodiffusion test (AGID).
It is named after Leroy Coggins, the man who developed the test.
Q: What does it test for?
A: The coggins test is a sensitive indicator of antibodies
directed against the EIA virus.
Q: Why should my horse be tested?
A: All horses should be tested at least annually, if they are
traveling they should be tested every six months. The reason they
should be tested is so that positive horses can be identified and
we can stop the spread of this disease.
Q: What is EIA?
A: Equine Infectious Anemia is also known as swamp fever. It is a
retrovirus, grouped with the lentiviruses; therefore, it is
related to the human AIDS virus. EIA is characterized by immune
mediated hemolytic anemia (red blood cell break down).
Q: How is EIA spread?
A: EIA is transmitted by blood. The primary mode of transmission
is by the bite of horse flies and deer flies. Other modes include
contaminated needles or surgical equipment. It can also be passed
from the mare to the foal in utero.
Q: Do any horses in the US really have a positive Coggins test?
A: Yes, in the US alone 2000 new cases are identified each year.
Besides the US, EIA has a worldwide distribution.
Q: What if my horse is positive?
A: EIA is a reportable disease. If a horse is identified as
positive, the state veterinarian should be contacted and the farm
should be quarantined. The choices for horses that test positive
are euthanasia, life long quarantine, or an EIA retirement home.
Q: What are the procedures for life long quarantine?
A: State and federal officials make the decision as to which
horses may be allowed to live in quarantine. The specifications
for life long quarantine include double screening of the area in
which the horse is housed, and physical separation of 200 yards
from any other equine.
Q: What are the clinical signs of EIA?
A: There are 3 common clinical forms of EIA.
Acute: fever, depression, small hemorrhages, sometimes death
Subacute-to-chronic: same as acute plus anemia, icterus, fatigue,
rapid breathing, edema, weight loss, colic and abortion
Chronic inapparent: few clinical signs, although clinical signs
may appear if the animal is stressed.
Q: What is the treatment for EIA?
A: There is no treatment.