The clinical manifestations of and epidemiological data from 11 patients infected with Vibrio vulnificus admitted to Danish hospitals during the unusually warm summer of 1994 are reported. All patients contracted the disease after exposure to seawater; however, none had consumed seafood. Four patients developed bacteremia, one of whom subsequently died; nine patients, including the four with bacteremia, exhibited skin manifestations. Four patients contracted the disease while fishing; in at least one case the patient had handled eels. All Vibrio vulnificus strains were highly susceptible to 11 antimicrobial agents tested. Plasmid analysis revealed that 8 of 11 strains carried plasmids. Ribotyping using the enzyme HindIII on the 11 strains showed five different types, two of which comprised four strains each. The present study provides the first clinical and epidemiological data about a series of human Vibrio vulnificus infections from a temperate zone.