On the serology of Vibrio vulnificus

The serology of 70 strains of Vibrio vulnificus was studied. Seven O-antigenic groups were defined among them and it was shown that the H antigens of all the strains were identical. A heat-labile masked antigen, which inhibits O agglutination, was found in some strains. As all O antisera for V. vulnificus contained some R antibody, all diagnostic O sera must be absorbed with R organisms before use.