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The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50 % detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ㎖ of water samples with 0.1 CFU/㎖ of L monocytogenes was inoculated into 10 ㎖ of UVM concentrated at 10-fold, and incubated for 24 h at 36 ℃. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total number of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1, L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 lgo CFU/㎖ for 1 week poststorage (5 and 20℃), but the pathogens were able to be detected in river and sea water unitl 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.
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