Lipp, E. K. University of South Florida/Dept.of Marine Science,
Rose, J. K. University of South Florida/Dept. of Marine Science,

Vibrio vulnificus is the most common cause of shellfish-associated human mortality in the United States. This organism occurs naturally in subtropical and temperate estuaries; therefore an ecological understanding of this bacterium is necessary to adequately predict high levels in shellfish and recreational waters. In this study, sediment and water samples were collected for one year in Charlotte Harbor (Florida) and analyzed for cultivable V. vulnificus. The greatest concentration detected in sediment was 9.04x10E5 CFU/100 g (dry weight), 10,000x that of the water column. The largest difference between sediment and water column concentrations occurred during spring and winter months when the mean level in the sediment was 1128 and 291 times that of the overlying water column. The seasonal variation appeared to be related to changes in salinity. The greatest levels of the bacterium in the water column and the lowest levels in the sediment were detected as salinity approached 15. Likewise, seeded studies demonstrated significantly less adsorption of V. vulnificus in a 1.5-% NaCl solution than in solutions with salinities of 25 or 30, indicating possible desorption near a salinity of 15. Results from this study illustrate the potential for environmental factors such as salinity to influence the distribution of V. vulnificus between sediment and water column.
Day: Thursday, Feb. 4
Time: 11:30 - 11:45am
Location: Sweeney Center
Code: SS10TH1130S