A survey on the occurrence of Vibrio parahaemolyticus on fish and shellfish, marketed in The Netherlands

Abstract

A survey was carried out on the occurrence of Vibrio parahaemolyticus on fish and shellfish, as sold in The Netherlands. The optimal mode of detection of this bacterium appeared to be: (i) enrichment of swabs taken from the surface and the gills in freshly prepared meat broth with 5% NaCl; (ii) streaking onto Teepol bromothymol blue agar (BTB) and taurocholate bromothymol blue sucrose agar (TCBS); (iii) confirmation of suspect colonies by testing for mode of growth in butts/slants of a Kligler type glucose sucrose iron thiosulphate agar, formation of indole in 2% NaCl 2% trypticase water, anaerobic utilization of starch in the presence of 5% NaCl and oxidase reaction according to Kovacs (1956). A total of 407 samples, stemming from 17 types of fish and shellfish, taken at three fish shops, was examined by this technique. Only one specimen, i.e. a haddock, was found to contain V. parahaemolyticus. This contamination rate of approximately 0·3% correlates well with data found earlier for fish landed in Northern Germany. © 1970, Cambridge University Press. All rights reserved.