Staphylococcus aureus biofilm: the role in disseminating antimicrobial resistance over the meat chain

Staphylococcus aureus is responsible for severe skin and respiratory infections and food poisoning, resulting in hospitalizations and high morbidity worldwide. Staphylococci have extensive virulence mechanisms and antimicrobial resistance that pose a global challenge to contain the spread of infectious outbreaks. Antimicrobials are used as growth promoters, and for prevention and treatment of infections in animals that provide us with food. The improvement of animal health is undeniable, but the selection of multidrug-resistant strains that can spread resistance genes among microorganisms is undesirable. The administration of sublethal doses of antimicrobials in farm animals causes stress to Staphylococci inducing the formation of a complex extracellular polymeric structure called biofilm. Such a structure may favor the persistence of infection by disseminating antimicrobial-resistant strains that can be consumed in contaminated food of animal origin. In ruminant mastitis and hospitals, the potential of the biofilm structure in the persistence of infections, especially those caused by S. aureus, has already been demonstrated, as well as its role as a source of resistant genes. In the meat production chain, the potential for persistent contamination by biofilm structure is evidently a worrying health risk. This review brings together studies demonstrating that biofilm production facilitates the exchange of mobile genetic elements and random mutations in S. aureus strains within the structure. This contributes to the emergence of more resistant clonal complexes and, with biofilm support, persists in the meat production chain.