Application of a Rapid Method for Detecting Vibrio Parahaemolyticus in Seafood

A double‐layer agar plate (DLAP) method was used to detect Vibrio parahaemolyticus in culture broth and seafood samples, which were added with certain amount of V. parahaemolyticus and then subjected to freezing treatment. The results of DLAP, which were compared with the most probable number (MPN) method and direct‐plating methods such as Bio‐chrome Vibrio medium (BCVM) and thiosulfate–citrate–bile salts–sucrose agar (TCBS), showed that they were not significantly different (P > 0.05) from each other under the normal experimental conditions. However, if the bacterium was inactive or injured, the results of DLAP were as effective as MPN and more accurate than those of BCVM and TCBS. Furthermore, DLAP showed the total agreement compared with the MPN method by examining the presence of V. parahaemolyticus in naturally contaminated seafood samples. Because of its sensitivity and exactness, DLAP offers a broad application for fast screening and detecting of V. parahaemolyticus in seafood. PRACTICAL APPLICATIONS: Consumption of raw or undercooked seafood, particularly shellfish, contaminated with Vibrio parahaemolyticus may lead to the development of acute gastroenteritis characterized by diarrhea, headache, vomiting, nausea, abdominal cramps and low fever. Now, this bacterium is recognized as an important seafood‐borne pathogen throughout the world. Usually, 5 to 7 days are required for V. parahaemolyticus detection by the most commonly used procedure – the most probable number method, which is very time‐consuming and labor‐intensive. Some time‐saving alternatives such as polymerase chain reaction or DNA methods are not economically appealing. The considerations demand for a rapid method for V. parahaemolyticus detection that is at least as sensitive and accurate as the methods used currently. A double‐layer agar plate method described here can satisfy these criteria and can be used for rapid detection of V. parahaemolyticus in artificially and naturally contaminated samples in laboratory testing.