Demonstration of agglutinating antibodies against Vibrio parahaemolyticus in the yellow tail flounder (Limanda ferruginea).

Sera from the salt water fish (Yellow tail flounder) and the fresh water fish (rainbow trout) were tested for the presence of circulating antibodies against nine strains of Vibrio parahaemolyticus and one of V. alginolyticus. Thirteen out of 26 flounder sera tested gave agglutinating reactions against one specific strain of V. parahaemolyticus; strain No. 3525. Seven rainbow trout sera tested failed to agglutinate any of the strains tested. All agglutinating activity was lost upon boiling the antigen, therefore, the fish antibodies are due to surface antigens (K-antigens) and not to somatic antigens. The specific V. parahaemolyticus strain No. 3525 belongs to the serological type 03:K30, which might be common to the sea waters of the Eastern United States. The possibility that fish serve as a reservoir to Vibrio parahaemolyticus and its possible implication in the transmission of human disease are discussed.