[An outbreak of food poisoning suspected due to Aeromonas and characteristics of the isolated strains].

On June 7, 1990, food poisoning with main symptoms of abdominal pain and diarrhea occurred in Inuyama City, Aichi Prefecture. From results of bacteriological examination, three kinds of mesophilic Aeromonas spp. were detected from patients, leftover foods, well water, and cookers, one of which was A. hydrophila which was shown to produce haemolysin thought to be the cause of the food poisoning. On the other hand, A. sobria and A. caviae isolated from various materials did not produce haemolysin. The latter two strains of mesophilic Aeromonas spp. did not produce any other enterotoxins. Therefore, it appears that the well water containing A. hydrophila, A. sobria and A. caviae polluted the foods, which then had caused the food poisoning. Of nine strains of A. hydrophila, five do not dissolve sucrose, and these are typed as serogroup O:22 or O:23. The other four strains dissolve sucrose, and these are typed as serogroup O:16. According to the drug sensitivity test, all of these nine strains of A. hydrophila were resistant to Ampicillin, Erythromycin and Cephaloridine.