DefinitionFood poisoning occurs when you swallow food or water that contains bacteria, parasites, viruses, or toxins made by these germs. Most cases of food poisoning are from common bacteria such as Staphylococcus or E. coli.Causes, incidence, and risk factorsFood poisoning can affect one person or a group of people who all ate the same contaminated food. It more commonly occurs after eating at picnics, school cafeterias, large social functions, or restaurants.The germs may get into the food you eat (called contamination) in different ways:Meat or poultry can come into contact with the normal bacteria from the intestines of an animal that is being processedWater that is used during growing or shipping can contain manure or human wasteFood handling or preparation in grocery stores, restaur