TRANSMISSION
Diarrheagenic pathotypes can be passed in the feces of humans and other animals. Transmission of E. coli occurs through the fecal-oral route, primarily via contaminated food or water. Transmission also occurs through person-to-person contact, as well as contact with animals or their environment. Although some animals may carry non-STEC diarrheagenic E. coli, people constitute the main reservoir for strains causing diarrhea in humans. The intestinal tracts of animals, especially cattle and other ruminants, are the primary reservoirs of STEC.