Incidence and biotyping of Aeromonas species from the environment.

A survey was carried out to establish the incidence rate of Aeromonas species in various environmental samples with a view to ascertaining their reservoirs and distinguishing the biotypes. High rates of isolation were obtained from snails and water. This indicates that these samples are likely reservoirs and therefore constitute high sources of human infection. Low incidence rates were realised from poultry, cattle and humans, thus suggesting that these samples may be transient hosts. Two species of Aeromonas were isolated: A. sobria, and A. hydrophila which was further split into two biotypes, viz A. hydrophila subspecies hydrophila and A. hydrophila subspecies anaerogenes. All were involved with infections in humans.