Escherichia coli (E. coli) is a group of bacteria found in the intestines of people and animals, and that can also be found in the environment. Most strains of E. coli are harmless and serve an important role in the digestive system. However, some strains of E. coli are pathogenic, meaning they can cause illness in humans. Many of these pathogenic E. coli cause diarrhea and are referred to as diarrheagenic E. coli. Other E. coli can leave the intestines and cause infections in other sites of the body such as urinary tract infections, blood stream infections, and respiratory illnesses.
For information regarding E. coli O157:H7 linked to romaine lettuce, check out our Outbreaks and Investigations page.
There are six pathotypes of E. coli that cause diarrhea in people. In Wisconsin, four of the six pathotypes are reportable:
- Shiga toxin-producing E. coli (STEC), which includes E. coli O157:H7—STEC, and may also be referred to as Verocytotoxin-producing E. coli (VTEC) or enterohemorrhagic E. coli (EHEC). This pathotype is the one most commonly reported in the news, in association with foodborne outbreaks.
- Enterotoxigenic E. coli (ETEC)
- Enteropathogenic E. coli (EPEC)
- Enteroinvasive E. coli (EIEC)
More information can be found on the Food Poisoning home page.