Clarifying the Dual Role of <em>Staphylococcus</em> spp. in Cheese Production

Staphylococcus spp. present a dual role during cheese production as some species may be pathogenic, while others bring beneficial characteristics to the final products. Coagulase-positive staphylococci (CoPS) species, particularly Staphylococcus aureus, are of concern due to their potential to produce enterotoxins commonly linked to foodborne outbreaks. These enterotoxins, encoded by a set of genes, can cause severe gastroenteritis, particularly vomiting. Many other members of the genus can harbor a wide range of genes encoding virulence factors and capability of forming biofilms on various surfaces. The alarming prevalence of antibiotic-resistant strains, including methicillin-resistant S. aureus (MRSA), further complicates their control. In contrast, some strains of coagulase-negative Staphylococcus species (CoNS) positively contribute to cheese ripening, influencing flavor and texture. Some strains are even considered safe for use in food production and have been studied as inhibitors of foodborne pathogens. Conversely, the expression of enterotoxin genes in some Staphylococcus species, particularly S. aureus, is regulated by different mechanisms including quorum sensing. Understanding enterotoxin gene expression in various environmental conditions, including during cheese production and ripening, can aid in developing targeted interventions. The risks posed by enterotoxin producing Staphylococcus in cheese are evident since numerous food poisoning outbreaks have been reported. Also concerning is the fact that several Staphylococcus species pose risks to animal health and livestock production. Effective control measures include adherence to microbiological criteria for CoPS and enterotoxin levels in cheeses with special attention to animal health, good manufacturing practices (GMP), temperature control, and strict hygiene protocols. This review highlights the need to balance the beneficial roles of CoNS in cheese production with the risks associated with virulent and enterotoxigenic strains of CoNS and CoPS.