The CDC estimates that 76 million foodborne illness, or food poisoning, cases occur in the United States every year, which means that one in four Americans contracts a foodborne illness annually after eating foods contaminated with such pathogens as E. coli O157:H7, Salmonella, Hepatitis A, Campylobacter, Shigella, Norovirus, and Listeria. Approximately 325,000 people are hospitalized with a diagnosis of food poisoning, and 5,000 die. The estimated costs in terms of medical expenses and lost wages or productivity are between $6.5 and $34.9 billion (Buzby and Roberts, 1997; Mead, et al., 1999).  While most foodborne illness cases go unreported to health departments, nearly 13.8 million food poisoning cases are caused by known agents – 30% by bacteria, 67% by viruses, and 3% parasites (Mead, et al., 1999).