Which bacterium is a major cause of staphylococcal food poisoning through preformed toxins?

Staphylococcus aureus is a major cause of staphylococcal food poisoning through preformed toxins.

Some strains of S. aureus produce heat-stable enterotoxins in foods. If food is handled by a colonized person and then left at a suitable temperature, the bacteria may multiply and release toxin. Eating the contaminated food can cause sudden nausea, vomiting, stomach cramps, and diarrhea.

Symptoms often begin within a few hours because the toxin is already present; the illness is not mainly caused by bacterial growth inside the intestine. Heating may kill the bacteria but does not always destroy the toxin.

S. aureus also causes skin infections and can include methicillin-resistant strains called MRSA. Bacillus cereus and Clostridium botulinum cause different toxin-mediated foodborne illnesses.