Domestic Cutting Boards as Reservoirs of Virulent and Antimicrobial-Resistant Listeria monocytogenes and Escherichia coli.

Cutting boards are key food-contact surfaces in domestic kitchens and may act as reservoirs for foodborne pathogens and antimicrobial-resistant bacteria. This study investigated the presence of Listeria monocytogenes and Escherichia coli in wooden and plastic cutting boards collected from Brazilian households, focusing on virulence and biofilm-associated genes, adhesion capacity, and resistance to antibiotics and sanitizers. From 100 cutting boards analyzed, 16 L. monocytogenes isolates and 15 E. coli isolates were recovered. Clinically relevant L. monocytogenes serotypes (1/2a, 1/2b, and 4b) were identified. Both species showed a high prevalence of genes associated with virulence and biofilm formation, although most isolates were classified as weakly adherent in vitro conditions. Antimicrobial susceptibility testing revealed a high frequency of multidrug resistance, particularly in E. coli, with 60.0% of isolates identified as extended-spectrum β-lactamase producers. Several L. monocytogenes isolates also showed resistance to clinically important antimicrobials. All sanitizers tested were effective under experimental conditions. These findings indicate that domestic cutting boards can harbor bacteria combining virulence potential and antimicrobial resistance, highlighting their role in household food safety and the dissemination of antimicrobial resistance.