INFLUENZA

Influenza vaccine, which is often combined with Rhinopneumonitis vaccine, is an important part of our "stable" of disease preventing immunizations.

Influenza causes a wide variety of symptoms and is spread rapidly and easily. These characteristics make it a particular problem at places where large numbers of horses gather, such as race tracks, show grounds, training barns, breeding facilities and sale barns.

The signs of Influenza are high fever, lethargy, nasal discharge and a loud, harsh cough.

The protection from this vaccine is relatively short lived, approximately 3 to 4 months; therefore, it should be administered more often to horses that are exposed to a lot of different horses, 3 to 4 times per year, or 2 to 4 weeks prior to a single event.

EASTERN AND WESTERN EQUINE ENCEPHALOMYELITIS

This virus stays active in bird and rodent populations, and is spread to horses (and humans) by blood sucking insects, such as mosquitoes.

The period that the virus is active in the infected horse is so short that the horse is not considered a reservoir of the disease, and is termed a "dead end host" of the disease (as are humans).

Neurologic disease is the hallmark of infection with this virus. The prognosis for horses that contract equine encephalomyelitis is poor.

Manufacturers of vaccines recommend once yearly immunization for adults, but studies demonstrate a shorter duration of immunity, approximately 4 to 6 months, which suggests twice yearly boosting.

Brood mares should be vaccinated 4 to 6 weeks prior to foaling, and primary vaccination of foals should begin at 3 to 4 months of age, with a minimum of two vaccinations 4 weeks apart.

Note: We usually administer EWT, which is EEE & WEE and Tetanus.

POTOMAC HORSE FEVER

Potomac Horse Fever (PHF) was originally described as a diarrhea producing colitis found in horses living near the Potomac River in Maryland.

The causative agent, Ehrlichia risticii is an intracellular parasite that infects blood cells that move into intestinal cells. Although never proven conclusively, it is thought that biting insects transmit this disease.

We really do not see this disease in Maine, but horses that travel to shows in Southern New England or New York should be protected against this disease.

After an initial 2 vaccination series, yearly boosters are recommended.

COGGINS

The Coggins Test, developed n 1970 by Dr. Leroy Coggins, D.V.M.,  tests for Equine Infectious Anemia. Equine Infectious Anemia is a viral disease that attacks a horse's immune system. There is no cure and no vaccine for this viral infection, which is caused by a retrovirus closely related to the HIV virus in humans, the cause of AIDS. It's recommended by the American Association of Equine Practitioners that horses testing positive for EIA antibodies be euthanized humanely. Most horses exposed to the equine lentivirus, the virus that causes EIA, progress without outward symptoms of the disease.

This test is especially important when traveling with your horse during show season, or whenever you plan to bring your horse to a new barn. Test regulations vary between states and events so make sure you call to find out what you will need in advance!

The state of Maine requires a valid Coggins test every three years, however certain other destinations require proof of a valid 6 month test. The Dressage Association requires an annual test. Be sure to check with your show or event sponsor to find out well in advance what the requirements are, as it may take several weeks to receive the results of your test after the blood sample is sent in for analysis.