Equine infectious anemia
The Coggins test is the most commonly used laboratory analysis for the antibodies to EIA. All states require that horses have a negative Coggins test before interstate movement. “Horse owners are strongly encouraged to incorporate an annual Coggins test into their animal health regimen regardless of whether they travel interstate,” said ISDA State Veterinarian Dr. Bill Barton. “Horses that acquire EIA are infected throughout their lives and will remain a source of infection to other horses in close proximity, so Coggins tests are incredibly important to managing the spread of EIA.”
The symptoms of a horse infected with EIA are often subtle and may go unnoticed. EIA-positive horses may develop a low-grade fever or become lethargic as well as demonstrate weight loss, yellowing of body tissues, anemia, swelling in limbs, and weakness. Not all EIA-positive horses will show signs of illness, and these animals serve as inapparent carriers. Horses demonstrating clinical signs of EIA pose the greatest risk of spreading the virus. However, inapparent carriers can be a source of infection and pose a risk to other horses. Idaho law has strict requirements for EIA-infected horses in the state, including isolation from other horses for the life of the animal.