Prevalence and phylogenetic analysis of Listeria monocytogenes isolated from the fillets of two farmed fish in Shahrekord in 2018

Fish and other aquatic animals, directly and indirectly, can be contaminated with Listeria monocytogenes and consequently, fish and their products are considered a carrier for this bacterium. The present study investigated the contamination of farmed rainbow trout and common carp with this bacterium as well as the phylogenetics of the isolates. A total of 50 samples of farmed fish were obtained from local fish supply centers in Shahrekord City from July to September 2018. Based on the molecular experiments, 18 (36%) of the 50 studied samples were contaminated with L. monocytogenes as 26% and 10% of the isolates were found in trout and carp, respectively. From 18 isolates, 12 samples (66.66%) belonged to serotype 4b, one belonged to serotype 1/2a and the other 5 samples belonged to serotype 1/2b. According to the results of the present study and regarding the importance of the bacteria in terms of public health, continuous and accurate hygienic monitoring seems to be necessary.