No abstract

SUMMARYThe seasonal variation in the occurrence of V. vulnificus in relation to water temperature and salinity was studied along the Dutch coast. In two consecutive years V. vulnificus strains could be isolated in August when the water temperature was highest. The indole-positive strains isolated from North Sea water samples were identical to most strains isolated from human disease and from the environment. However, strains isolated from four of five patients living in countries around the North Sea were different from the North Sea isolates in that they were indole-negative and have a lower NaCl tolerance.

A 63‐year‐old man was admitted to hospital for septicaemia and severe metastatic skin infection, 24h after he had eviscerated fresh eels. V. vulnificus was isolated from his blood and wounds. The strain was indole negative, was ornithine decarboxylase positive and grew at 42°C. A strain of V. vulnificus with these characteristics was isolated in 1987 from diseased eels. The characteristics differed from those of V. vulnificus strains (biogroup 1) that have been reported from patients world‐wide. V. vulnificus biogroup 1 was isolated from 3 of 11 seawater samples collected along the coast of the Netherlands, but indole negative strains of V. vulnificus were not isolated. We conclude that an indole‐negative variant of V. vulnificus is pathogenic for eels and for human beings and that eels may transmit V. vulnificus to humans.