Prevalence and antibiotic resistance profile of Listeria spp. associated with seafoods from fish catchment areas in Kerala, India

Abstract

Background and Aim: Listeria monocytogenes is a ubiquitous, intracellular pathogen which has been implicated as a cause of several foodborne outbreaks. This study aimed to generate information on the prevalence and antibiotic resistance profile of Listeria species isolated from seafood. Materials and Methods: A total of 400 samples of fresh fish, 100 samples of dry fish and 200 samples each of crustaceans and mollusks were collected from the fish catchment areas. All the samples were subjected to isolation and identification of Listeria spp. by two-step enrichment in UVM broth and plating on selective agar media (PALCAM) and then subjected to molecular characterization. L. monocytogenes isolates obtained during the study were subjected to serotyping by multiplex polymerase chain reaction. The isolates were also subjected to antibiotic sensitivity test. Results: The prevalence of L. monocytogenes in seafoods in the present study was 0.55%. The isolates of L. monocytogenes were found to possess all virulence genes, namely, iap, hlyA, actA, prfA, plcA, and inlA. All the isolates belonged to serotype 4b. The occurrence of Listeria innocua was found to be more and was detected in 16.77% of seafoods samples. Antibiotic sensitivity test revealed that all isolates were resistant to cefixime but were sensitive to almost all other commonly used antibiotics. Conclusion: The presence of Listeria spp. in raw seafood samples augments the need for implementation of good hygienic practices during the handling and processing of seafoods to safeguard the health of the consumers.

Listeria monocytogenes from Marine Fish and the Seafood Market Environment in Northern Greece: Prevalence, Molecular Characterization, and Antibiotic Resistance

“…The recent European Union One Health zoonoses report states that L. monocytogenes was detected in 7.1% of ready-to-eat fish and fishery products, one of the highest among ready-to-eat foods in the European Union [7]. The prevalence of Listeria monocytogenes in seafood depends on several factors, such as the geographic area, the water quality, the seasonality, and the discharge of agricultural effluents in water bodies ending up in the sea [12][13][14]. The prevalence of the pathogen usually varies between geographic regions; furthermore, the variation in prevalence and serotypes between different regions is mainly caused by environmental factors and climatic differences between countries.…”

“…These differences may affect the presence and proliferation of Listeria monocytogenes and, therefore, affect the risk posed by this foodborne pathogen. Additionally, the water quality and pollution levels prevailing in each region affect the prevalence of Listeria monocytogenes [12,14]. In cases where the fish-rearing areas receive livestock effluents, the possibility of the occurrence of this pathogen in the seawater is augmented, resulting in the contamination of the aquatic animals and seafood produced there [13].…”

“…Also, the eating habits of marine animals affect contamination with a pathogenic bacterium or the multiplication of it. More specifically, filter-feeding organisms, such as mussels, can readily accumulate pathogens in their tissues compared to fish [12].…”