A review on prevalence of Listeria monocytogenes in raw seafood

Listeria monocytogenes is an important food pathogen that can survive in food under adverseenvironmental conditions (low pH, high salt levels, and refrigerated temperatures). Listeria is aubiquitous bacterium that can be naturally isolated from water, sewage, sludge, and soil. Researches showthat the environment is a natural reservoir for Listeria. Therefore, the purpose of this research is toinvestigate the prevalence of Listeria monocytogenes in raw seafood in Iran and other countries. Theresults of this research showed that the level of contamination in different countries is very different. Inthe USA, the contamination rate of Listeria monocytogenes has been reported as ۳۷-۴۳% in catfish fillets,۴.۳% in tilapia, and ۲.۶% in shrimp samples. In Finland, it has been reported that up to ۳۵%contamination of rainbow trout with Listeria. In the studies conducted in Japan, the level of Listeriamonocytogenes contamination of different aquatic animals varied from ۰ to ۲۱%. The contamination rateof fish and shrimp in India has been reported from ۱.۲ to ۱۴%. Moreover, in Chile, the contaminationlevel of fresh shrimp has been reported up to ۲۸%. In Iran, the contamination rate of fish and shrimp hasbeen reported between ۰ and ۷.۷%. In general, according to the obtained results, it can be stated that theprevalence of Listeria monocytogenes in marine animals depends on several factors, including thevariable species of aquatic animals in different countries, the test method, the sampling season, the type ofproduct, and the region. Due to the very high mortality rate of listeriosis, it is important to continuouslymonitor the prevalence of Listeria monocytogenes in order to control the disease.

Keywords:

Listeria monocytogenes , Listeriosis , Seafood products