Isolation and identification of Aeromonas from patients with acute diarrhoea in Kolkata, India

Isolation of diarrhoea causing Aeromonas was carried out in the division of Active Surveillance, National Institute of Cholera and Enteric Diseases (NICED), Kolkata for a period of 12 months from January 1999 to December 1999. Out of 602 stool samples collected from patients with acute diarrhoea admitted in Infectious Diseases (ID) Hospital, Kolkata, 64 (10.6%) samples were identified positive for Aeromonas as the pathogen. The different isolated and identified species from patients with acute diarrhoea were A. hydrophila (60%), A. caviae (20%), A. veronii (10%), A. schubertii (4%), A. jandaei (3%), and A. trota (3%). Most of the isolated Aeromonas strains showed resistance to commonly employed antibiotics. All the clinical isolates of Aeromonas possessed virulence genes encoding for aerolysin and cytotonic enterotoxin genes. Except A. schubertii and A. jandaei, all the other species possessed the gene for haemolysis.