This paper consists of a brief review on equine Infectious anemia added of the results of serological diagnosis of this infection performed at the Federal University of Santa Maria, RS, Brazil, between 1979 to 1990. A total of 7,035 serum samples were tested by the agar gel immunodiffusion test (Coggins test), to which 40 (0,57%) reacted positively. This percentage of positivity is lower than in other regions of Brazil, probably due to the lack of predisposing factors for equine infectious anemia virus spread, such as, a low density of blood-sucking insects in the South of Brazil and the seldom use of massive therapies and vaccinations in the region.