A food borne illness is caused by eating contaminated food containing harmful microorganisms. Microorganisms can contaminate food during production or handling if food is left in the danger zone between 4-60 degrees Celsius where bacteria multiply rapidly. Common food borne illnesses include salmonella from undercooked eggs or poultry, E. coli O157:H7 from undercooked ground beef, and norovirus often associated with raw oysters during winter months. Proper food safety practices like keeping food at safe temperatures, thoroughly cooking foods, and washing hands can help prevent contamination and illness.