Prevalence and Phenotypic Antimicrobial Resistance of Listeria monocytogenes from Animal-Derived Foods: A Scoping Review

Listeria monocytogenes is one of the leading foodborne pathogens and an increasing public health concern because of the emergence of antimicrobial-resistant strains. This scoping review aimed to synthesize the available evidence on the prevalence and phenotypic antimicrobial resistance profiles of L. monocytogenes in animal-derived foods. The review was conducted following the Joanna Briggs Institute methodology and the PRISMA-ScR guidelines through systematic searches of PubMed/MEDLINE, Scopus, Web of Science, and Embase. Of the 711 records identified, 11 studies met the eligibility criteria. The included studies reported the occurrence of L. monocytogenes in meat and meat products, milk and dairy products, and ready-to-eat foods. The reported prevalence ranged from 0.1% to 60.0% across food matrices; however, the highest estimate (60.0%) was derived from a single ready-to-eat food study with a small sample size (9 positive samples among 15 analyzed) and should therefore be interpreted cautiously. Phenotypic resistance was most frequently reported to specific β-lactams, particularly penicillin, oxacillin, cloxacillin, cefotaxime, ceftriaxone, and piperacillin, as well as to tetracyclines. In contrast, several studies reported preserved susceptibility to ampicillin and amoxicillin, indicating substantial variability in resistance within the β-lactam class across the included studies. This scoping review provides an updated synthesis of the available evidence on the prevalence and phenotypic antimicrobial resistance profiles of L. monocytogenes in animal-derived foods and summarizes the phenotypic antimicrobial resistance patterns reported across the included food matrices.