Escherichia coli is a Gram-negative cane (bacillus) of the Enterobacteriaceae family. Most E. coli are normal diners found in the digestive tract. The pathogenic strains of this organism are distinguished from normal flora by possessing virulence factors, such as exotoxins. Enteropathogenic Escherichia coli cause damage to the mucosa causing inflammatory responses. Because of this, it is the most common type of diarrhea in infants and is sometimes associated with vomiting and fever. It is common in developed and developing countries.