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Escherichia coli (E. coli) are gram-negative bacteria and are a type of fecal coliform bacteria commonly found in the intestines of animals and humans E. coli are so small they can’t be seen without a microscope; however, their growth can be seen as colonies on agar media (like JELL-O) under special conditions (Ingerson and Reid, 2011). Most E. coli do not cause illness but if a person becomes sick from E. coli, the primary site of infection is the gastrointestinal tract and symptoms can include nausea, vomiting, diarrhea, and fever. This bacterium lives and grows naturally in the gastrointestinal tract of humans and animals but if it gets in the wrong place in the body, for example, the kidneys or blood, it can cause illness. According to Ingerson and Reid (2011), the infection may spread within the body (to blood, liver, and nervous system). These microorganisms are shed in fecal material, or feces, hence their spread is termed the “fecal-oral” route of transmission. Contaminated food and water are the most common ways to be exposed to E. coli. There are specific types (also called “strains”) of E. coli that can cause disease and there are also harmless types. Some of the harmful types of E. coli are classified into the following groups: Enterotoxigenic (ETEC), Enteropathogenic (EPEC), Enterohemorragic (EHEC) and Enteroinvasive (EIEC). ETEC, EPEC and EIEC are all generally transmitted through contaminated food and water (Gerba et al., 2009 and Vieira et al., 2007). Table 1 summarizes the harmful types of E. coli, mode of transmission, and disease outcome. A more well-known type or strain of E. coli is O157:H7 which is found under the EHEC group and is commonly the cause of contaminated foods such as spinach and meat but has also been implicated in outbreaks where water was the source of contamination.