Evaluation of nonisotopic DNA hybridization methods for detection of the tdh gene of Vibrio parahaemolyticus

Production of the thermostable direct hemolysin (TDH) by Vibrio parahaemoly ticus is associated with pathogenicity of the organism and is encoded by th e tdh gene. The timely resolution of seafood-associated outbreaks requires rapid and accurate detection of pathogenic V. parahaemolyticus. The specifi city of alkaline phosphatase- and digoxigenin-labeled tdh gene probes was e valuated against 61 strains of V. parahaemolyticus (including isolates from recent outbreaks involving oysters from the Pacific Northwest, Texas, and New York), 85 strains of other vibrios, and 7 strains of non-vibrio species from clinical and environmental sources. The probes were specific for dete ction of the V. parahaemolyticus tdh gene.