Coggins Test: What, When, & Why

If you’ve ever hauled your horse out of state, entered a horse show, or taken your horse to a new boarding facility, chances are you were asked to provide proof of a current negative coggins test. 

So what exactly IS a coggins test?

The coggins test was named after Dr. Leroy Coggins, the veterinarian who helped develop the laboratory test for Equine Infectious Anemia, or EIA. 

For a coggins test to be completed, a licensed veterinarian needs to draw the blood, and take pictures of the horse’s left and right side, as well as face. The veterinarian will also document all markings on your horse, as well as the horse’s name, name and address of owner, name and address of the stable, and the age, breed, and sex of the horse. The certificate may also list a microchip and registration number, if applicable. Please note, we cannot change the name on an EIA certificate after it is created - we would have to do a completely new blood draw! So help your veterinarian out and make sure they know how to spell your horse’s name!

Most EIA certificates are considered “current” for 12 months after the date of blood draw - but check with the requirements of your horse’s destination, as they may vary.

What are we testing for?

EIA is caused by a viral infection that is spread by biting flies. The infection can also be transmitted through the use of blood-contaminated injectable medications, improperly sterilized equipment, or blood products such as plasma. The virus can infect horses, ponies, donkeys, mules, and other equines. EIA infections can result in fever, lethargy, anemia, chronic muscle wasting, and death. Horses that survive infection will remain lifelong carriers of the virus, though they may not show any outward signs of illness. Unfortunately, these horses continue to pose a risk for transmitting the virus to other animals.

Why test?

There is no treatment for EIA or vaccine for its prevention. Legally, horses diagnosed with EIA in the US must be either quarantined for life or euthanized. Our best way to control the spread of this virus is through widespread testing, especially when horses are traveling and coming into contact with others. Fortunately, EIA now has a very low rate of incidence in the United States.