Equine Infectious Anemia (EIA) is a viral disease that affects horses, donkeys, and mules. It is caused by the Equine Infectious Anemia Virus (EIAV), which is transmitted primarily through blood-sucking insects, such as horseflies and deerflies. Infected animals can show symptoms like fever, weakness, and swelling, but some may not exhibit any signs at all. There is no cure for EIA, and infected animals must be permanently removed from the herd to prevent the spread of the virus. Testing for EIA is essential for horse owners, especially before events or sales, to ensure the health and safety of all equines involved.