[Seasonal change of Vibrio vulnificus in the slime of tidal flats, seawater, and fishes collected along Ariake Sea, Japan].

To investigate the seasonal change of Vibrio vulnificus in Ariake Sea, Japan, we attempted to isolate V. vulnificus from the slime of tidal flats, seawater, and fishes obtained from three harbors along Ariake Sea. The sample were collected twice a month from January to December, 2001. Also, we determined the biological characteristics of the individual isolates. V. vulnificus were isolated throughout the year, but the isolation ratios were higher during the warmer season from June to October. The isolates in the warmer season were able to grow in culture media containing 0.5% NaCl, whereas those isolated in the remaining seasons could not. Moreover, the isolates in the warmer season showed a greater hemolytic activity than those isolated in the remaining seasons. These results suggest that V. vulnificus isolated in warmer seasons are more vigorous in nature than those isolated in the remaining seasons.