Kinds of E. coli

Key points

  • Six kinds of E. coli can cause diarrhea.
  • Some of these E. coli also can cause other symptoms.
  • People get infected with these E. coli in several ways.
Medical illustration of E. coli, rod-shaped bacteria covered in tiny strands called cilia and many long, thin appendages called flagella.

E. coli that cause diarrhea

E. coli are a large group of bacteria (germs).

Most E. coli are harmless and are part of a healthy intestinal tract. These E. coli help digest food, produce vitamins, and protect us from harmful germs.

But some E. coli can make people sick, including six kinds that cause diarrhea. They are

  • STEC: Shiga toxin-producing E. coli
  • ETEC: Enterotoxigenic E. coli
  • EPEC: Enteropathogenic E. coli
  • EIEC: Enteroinvasive E. coli
  • EAEC: Enteroaggregative E. coli
  • DAEC: Diffusely adherent E. coli

Ways people get infected

People can get infected with these E. coli in several ways. These ways include

  • Eating contaminated food or drinking contaminated water
  • Contact with animals, their poop, or their environment
  • Contact with the poop of an infected person

Not all E. coli are alike

All six kinds of E. coli can cause diarrhea. Some kinds can cause bloody diarrhea, watery diarrhea, or both.

Some of these E. coli can cause other symptoms, including stomach cramps, vomiting, and fever.

Other things that vary for these E. coli include

  • Groups of people most affected
  • Major sources of infection
  • Where infection is more likely to happen

At a glance

This table describes the six kinds of E. coli that cause diarrhea.

Notes

  • STEC infection is the most common cause of hemolytic uremic syndrome (HUS).
  • ETEC infection is the leading cause of travelers' diarrhea.
  • Mucus is thick fluid produced by some parts of the body, including the nose, lungs, and intestines. It may be slippery, slimy, or jelly-like.
  • The World Bank assigns countries to four income groups: low, lower-middle, upper-middle, and high. The classifications are updated each year on July 1.