Comparison of selective media for the detection of Vibrio vulnificus in environmental samples

Aims: To compare two selective agars, cellobiose-colistin (CC) agar and a modification of the Vibrio vulnificus medium (VVMc agar), for the isolation of Vibrio vulnificus from environmental samples. Methods and Results: The efficiencies of recovery of V. vulnificus collection strains on CC, VVM, VVMc and on thiosulphate-citrate-bile salts-sucrose (TCBS) agar were compared and similar efficiencies were obtained. A slightly hi,,her recovery was observed on VVMc agar. The detection of V. vulnificus in environmental samples (eels and water) was performed by combining culture-based methods (CC and VVMc agars) with DNA-based methods using species-specific probes based on the cytolysin-haemolysin and the 16S rDNA genes. A lower accompanying microbiota was found on CC agar than on VVMc agar. Conclusions: The comparison between CC and VVMc agars confirms that both are useful for the detection of V. vulnificus in environmental samples. However, the use of any of these media should be combined with a species-specific probe. Significance and Impact of the Study: The combined use of a selective medium and a specific probe provides a feasible method for the detection of V. vulnificus for epidemiological and ecological studies.