"Swamp fever" is a generic term for any infection that typically occurs in humid environment like swamps and is transmitted by mosquitoes or other blood sucking insects that thrive in humid environment. Two very common examples are Malaria and Leptospirosis. Equine infectious anemia also falls in this category. It is caused by a retrovirus, similar to HIV in humans, which is transmitted by bloodsucking insects, like horse flies, deer flies and stable flies. In addition to horses, it can be found in zebras, ponies, donkeys and mules.