Most horse owners are familiar with a Coggins test, as it is often required for travel, entrance to shows, and for stabling at boarding barns.  For horses who do not travel and are pastured in a closed herd, is the annual test really necessary?


What is a Coggins test?

A Coggins test is a serology test that detects the presence of antibodies for equine infectious anemia virus (EIA).  By testing all horses, we can monitor and prevent the spread of virus carriers and infections.  Standard test results can take several days, so it is important to plan ahead before making travel plans if your Coggins is nearing its expiration date.


What is Equine Infectious Anemia?

EIA is lentivirus that causes slow disease progression and is often fatal.  EIA is transmissible through the transfer of blood between horses, often by the interrupted feeding of insects such as horse flies.  The virus is at its greatest potential of transfer when large numbers of horses are in close contact.  There is no vaccine for EIA, nor any treatment or cure for infected horses.  To control the spread of the virus, a horse who is positive for EIA should be put under permanent quarantine or euthanized.


Does my horse have to be tested?

Each state has it own regulations regarding EIA testing and transportation.  While most transportation documents require proof of a current negative Coggins, your state may not require each horse to be tested annually if they are not traveling.  It is important to note that most horse shows, organized trail rides, boarding barns, and other equine events require proof of current negative Coggins before allowing entrance, regardless of location.



We always recommend that all horse owners have Coggins tests pulled on each of their horses annually.  Proper and regular testing has significantly reduced the incidence of EIA.  Currently, the best method of keeping track of the virus is by testing as many horses as possible, regardless of their exposure risk or the state requirements.  It is important to remember that EIA is transferred through biting insects like horse flies, who can travel some distance.  Untested horses pose a risk to other horses in the area.

Additionally, while you may not plan to take your horses anywhere or bring a new horse in, you can never predict an emergency situation that may require you to move your horses, such as a flood, fire, or other catastrophic event.  Being without a current negative Coggins puts you in the unnecessary situation of organizing travel and finding a suitable place to stable your horses.