[Studies on bacterial agents in acute diarrheal disease (1985-1987)]

A three-year epidemiological study (from January 1985 to December 1987) was carried out on sporadic cases of acute diarrhea. A total of 2889 fecal specimens in Cary-Blair transport medium were examined for bacterial enteric pathogens, and 832 strains of fifteen species were isolated from 739 specimens, 73 patients having two or more pathogens. C. jejuni shared 51.7%, Salmonella spp. 18.3%, V. parahaemolyticus 10.3%, and Aeromonas spp. 15.7% of total fecal specimens. Isolation rates of C. jejuni and Salmonella spp. in children under the age of fifteen years (19.3%, 6.4%) were higher than those of older years (9.8%, 3.9%), respectively. Isolation of C. jejuni decreased to 24% (12/50) during 2-4 days storage at room temperature in Cary-Blair transport medium, which showed the necessity of rapid plating for isolation of C. jejuni from fecal specimens. Incidence of A. caviae in children up to ten years of age was significantly higher as compared with those of other Aeromonas species. Desoxycholate-hydrogen sulfide-xylose-agar (DHXA) was used for direct plating technique and for plating after enrichment with alkaline peptone water (without NaCl), which was found suitable as an enrichment medium for Aeromonas spp. Enterohemorrhagic E. coli (EHEC) O157:H7 was isolated from 3 patients by using desoxycholate-hydrogen sulfide-sorbitol-agar (DHSA).