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In order to study the growth and survival of enteric pathogens causing water-borne infections in sewage, the filtersterilized and autoclaved sewages of Dae Gu City were inoculated with Salmonella typhimurium, Shigella flexneri 2a, Sh. sonnei I, Vibrio eltor and V. parahaemolyticus, as test series and Escherichia coli as control. After varying periods of incubation up to 15 days at 4o, 15o, 25o and 37oC, viable cells in the inoculated sewages were counted by colony count technique. Distilled water and 0.9% saline were subjected to inoculation of the organisms was observed in the filter-sterilized and autoclaved sewages at 4o, and the sewages became sterile within a few days. At 15o, no growth and rapid inactivation of the organisms in the filter-sterilized sewage and slight or no growth in the autoclaved sewage was noted. Some viable cells were found in the autoclaved sewage after 15 days. A considerable growth was observed in the filter-sterilized and autoclaved sewages, at 25o and 37o, and large numbers of viable cells were found even after 15 days of incubation. In general, the autoclaved sewage supported the growth more noticeably than the filter-sterilized, except for V. parahaemolyticus which grew well in filter-sterilized sewage. No marked difference was noted between incubations at 25o and 37o, but V. parahaemolyticus showed a slightly more active growth at 25o than at 37o. Distilled water inactivated the organisms within a few days, but saline supported the growth at 25o and 37o. Marked differences were noted in the survival test of sewages pathogens of different origins.
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