Prevalence and Antimicrobial Resistance Profile of Listeria monocytogenes from Retailed Fresh Cat Fish and Frozen Fish in Abuja, Nigeria.

Abstract

This study investigated the prevalence and antibiotic resistance profile of Listeria monocytogenes from fresh catfish (Clarias species) and frozen raw fish (Mackerel and Herring). A total of 180 samples which comprised 60 units of fresh catfish, mackerel, and herring frozen fish each distributed uniformly across three locations in Abuja, were randomly collected within a period of three months. The samples were analyzed using standard bacteriological methods at the Animal science/bacteriology laboratory, Faculty of Agriculture, University of Abuja. Presumptive isolates were further serotyped using latex agglutination and subjected to antimicrobial sensitivity testing at the Advance Biotechnology laboratory (SHESTCO) Sheda, Abuja. Overall prevalence of L. monocytogenes in this study was 10.6% (n=19/180) distributed across Gwagwalada (20%), Bwari (11.7%) and none in Kwali Area council. The occurrence according to fish types showed 18.3% in mackerel, 10.0% in herring fish while 3.33% was from catfish. There was no statistically significant difference (p>0.05) between the prevalence of Listeria monocytogenes in the fish type studied. Antimicrobial resistance profile indicated high MAR index (≥ 0.4) which revealed a diverse spread of bacterial resistance to antibiotics within the fish population in the study area. This was characterized by 100% resistance of L. monocytogenes isolates to ampicillin and tetracycline while few (5) isolates were susceptible to chloramphenicol (71.5%), streptomycin (61.2%). This finding provides a baseline information on the prevalence and antibiotic profile of L. monocytogenes in catfish and frozen fish in Abuja, Nigeria. Proper hygienic handling of fish during processing and sales is optimum in mitigating the risk of foodborne illness due to L. monocytogenes. Adequate control of antimicrobial agent usage is also recommended to reduce the occurrence and spread of potential multidrug resistance strains.