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 m odification 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 collecti on strains on CC, VVM, VVMc and on thiosulphate-citrate-bile salts-sucrose (TCBS) agar were compared and similar efficiencies were obtained. A slightl y hi,,her recovery was observed on VVMc agar. The detection of V. vulnificu s in environmental samples (eels and water) was performed by combining cult ure-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 ar e useful for the detection of V. vulnificus in environmental samples. Howev er, the use of any of these media should be combined with a species-specifi c probe. Significance and Impact of the Study: The combined use of a selective mediu m and a specific probe provides a feasible method for the detection of V. v ulnificus for epidemiological and ecological studies.