Staphylococcus aureus is a common cause of food poisoning. It is faily heat-resistant. When undercooked or improperly heated food is ingested, the enterotoxins of Staph. aureus cause food poisoning. These enterotoxins are superantigens stimulating lymphoid cells, macrophages and T cells to release cytokines, IL-1 and IL-2 respectively. They stimulate the vomiting center in brain causing nausea and vomiting. Vomiting is the characteristic feature of food poisoning. It may be with or without non-bloody watery diarrhea.