Detection of Listeria species in fresh fish and fish market environment by IMS technique in Turkey

The incidence of Listeria spp. was investigated in fresh fish (n = 100) sold at retail markets and in the environmental and personnel samples (n = 100) obtained from several fish markets in Afyonkarahisar, Turkey by immunomagnetic separation technique. The fish samples analysed included anchovy, trout, carp and grey mullet (25 of each). Six (6 %) of the fish samples were found positive for Listeria spp. and the overall incidence of Listeria spp. was 10 % in the environmental and personnel samples. Three Listeria spp., Listeria monocytogenes, L. ivanovii, L. grayi were recovered from the samples examined. In addition, L. seeligeri from a fish sample and L. innocua from an environmental sample (box) were isolated. It was found that L. monocytogenes was only detected in fresh water fish with an incidence of 8 %. For the environmental samples, knives and refrigerators had the highest (20 %) and personnel samples had the least (5 %) levels of contamination. It can be concluded that the fish sold at retail markets are moderately contaminated with various species of Listeria including L. monocytogenes, which may pose a risk for human health. The presence of these bacteria in environmental and personnel samples of fish markets is also an important possible sources of cross-contamination of the fish and other seafood. The results of this study indicate the necessity of the implementation of good hygiene and sanitary practices in order to prevent and/or reduce the contamination of fishery products by Listeria spp. at the retail level.