DISTRIBUTION OF AEROMONAS-PHENOSPECIES AND GENOSPECIES AMONG STRAINS ISOLATED FROM WATER, FOODS OR FROM HUMAN CLINICAL-SAMPLES

A total of 332 Aeromonas spp. originating from drinking water (n = 75) , fresh water (n = 57), chicken and ground beef (107), human faecal sa mples in association with travelling (n = 49), human faecal samples no t associated with travelling (n = 38), and six strains from human bloo d cultures were studied by phenotypic methods and by using analysis of ribopatterns as a molecular method for the identification of the 13 k nown hybridization groups (HGs). Also included were the reference stra ins of each HG. A. hydrophila HG 1, A. caviae HG 4 and A. veronii biot ype sobria HG 8/10 were the most important genospecies identified in h uman faecal samples. A. hydrophila HG 2 and A. media HG 5B predominate d in drinking water and A. hydrophila HG 2 and HG 3, A. media HG 5A an d HG 5B predominated in fresh water. In drinking water only one isolat e was A. hydrophila HG 1 and two isolates were A, caviae HG 4. Clinica lly important Aeromonas spp. HG 1 (A. hydrophila), HG 4 (A. caviae) an d HG 8/10 (A. veronii biotype sobria) were common in chicken and groun d beef. In contrast to the drinking water samples, HG 5A was common in chicken and ground beef samples. Atypical, unidentified isolates were most often found in fresh water samples (12/57 strains). Although wat er has been suspected of being an important source of human aeromonas infections, clinically important HGs were found to be in the minority among Aeromonas spp, identified in drinking water or fresh water. The distribution of Aeromonas spp. HGs among drinking water, chicken and g round beef samples was also different, suggesting that contamination o f meat or chicken may not originate from water.