Occurrence of haemolysin producing Aeromonas species in the aquatic environment.

A total of 532 environmental isolates of motile aeromonads were evaluated for their ability to produce haemolysins. Of those isolates tested, 68 (12.5%) and 18 (3.4%) were found to be alpha and beta haemolytic, respectively. Aeromonas caviae was found to be alpha haemolytic (3.8%) for the first time. Isolates of Aeromonas which were either alpha or beta haemolytic on plate assay also produced detectable amounts of haemolysin in cell free broth assay.