Virulent strains of Vibrio vulnificus isolated from estuaries of the United States West Coast.

Vibrio vulnificus was isolated from United States West Coast estuaries at a low frequency (5.9%) from 529 samples of water, shellfish, and sediment. Four strains tested with iron-treated mice had 50% lethal dose values ranging from 7.6 to 360 CFU, compared with a 50% lethal dose of 4.9 CFU for a clinical isolate that caused the death of a septicemic patient. The presence of this pathogen may be a hazard to users of marine beaches and consumers of raw shellfish on the West Coast, especially to persons most susceptible to V. vulnificus septicemia. Species-specific antiflagellar serum and a gene probe for cytotoxin-hemolysin production were useful for screening these environmental isolates.