In Pennsylvania 22 Horses Destroyed Due to EIA

The total number of horses which have tested positive for equine infectious anemia (EIA) in northeastern Pennsylvania has risen to 23. Twenty-two of the horses have been destroyed, and three remain under quarantine. Another horse tested positive in Lebanon County, but the Pennsylvania Department of Agriculture (PDA) has been unable to link that horse with the positive reservoir group. Two other cases of EIA were detected earlier in 1999 in the state. The first cases in the current positive group were detected at an auction on Sept. 18. EIA, an incurable viral disease, can be detected by a blood test known as a Coggins test. Often compared to HIV or AIDS in humans, EIA is spread through contaminated blood via biting flies, and through improper use of equipment and needles.

The management of the auction in the northeast corner of Pennsylvania, where the positive horses were discovered, decided to give the additional service of Coggins tests through a private practicing veterinarian. Blood samples were taken the Saturday of the sale, and results were returned the following week after the horses were dispersed. Two of the 100-plus horses at the auction tested positive, but showed no clinical signs of EIA.

According to Bruce Schmucker, VMD, a veterinarian at PDA, the night of the auction was relatively "chilly" and insect-free, which reduced the risk of disease transmission. Fortunately, all horses exposed at the sale were located and tested negative except for one horse, which officials say has "vanished."

The two horses which were test-positive at the auction site were traced to two Wayne County camp herds. Ten of 20 horses were positive in one herd, while two of 65 horses were positive in the other herd. Both farms were quarantined for 45 days after the 14 positive horses were euthanized. In terms of incubation of the disease, an exposed horse is expected to test positive within 20 days if it contracts the disease. Some horses might take longer to seroconvert—25 to 28 days. "That is why we wait 45 days. It is highly unlikely that horses will turn sero-positive after 45 days," assures Schmucker. All of the suspect horses in Wayne County have been released from quarantine.

The ability of PDA officials to identify 23 positive horses is considered a success since those positive horses have been removed as a source of the disease. Schmucker was in practice for several decades preceding his position at the PDA. He explains that of the 60-plus positive horses which have been discovered since he began his veterinary career, only one case was diagnosed because of clinical signs. Most horses with EIA are discovered through testing.

Currently, the Commonwealth of Pennsylvania requires that horses entering the state be accompanied by proof of a negative Coggins test taken within the last 12 months. Such documentation is not required of horses destined for slaughter or horses at the time of sale. Schmucker believes the outbreak has raised the state’s awareness of the value of having horses checked, and of not allowing test-negative horses to come into contact with horses which have not been checked.

Is new legislation requiring more rigorous testing on the way? Schmucker explains that the PDA’s job is to administer the laws after they are written by legislators, although the department is asked for input. Twenty-two field personnel work for the PDA, on everything from cows to fish. Therefore, due to the number of horses being transported in the state, not every horse crossing the boarder can be checked.

Schmucker says an effort is being made to educate and generate awareness among horse owners in the region.

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

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