E. coli (diarrhea causing)

E. coli O157:H7 Romaine Lettuce Outbreak:

  • The Wisconsin Department of Health Services (DHS), the Centers for Disease Control and Prevention (CDC), U.S. Food and Drug Administration (FDA), and numerous other states are investigating a multistate outbreak of E. coli O157:H7 infections.
  • Nationwide, 197 people from 35 states have been infected with the outbreak strain of E. coli O157:H7. Illnesses started on dates ranging from March 13, 2018, to May 12, 2018.
  • To date, 89 people have been hospitalized, with five deaths reported.
  • Information collected to date indicates that romaine lettuce from the Yuma growing region could be contaminated with E. coli O157:H7 and could make people sick.
  • As of May 30, 2018, three Wisconsin E. coli O157:H7 infections have been linked to the outbreak.
Wisconsin E. coli O157:H7 Outbreak Case Count 2018
Updated May 30, 2018
Wisconsin Case Count 3
National Case Count (including Wisconsin cases) 197



Consumer Advice:

  • According to the U.S. Food and Drug Administration, the last shipments of romaine lettuce from the Yuma growing region were harvested on April 16, 2018, and the harvest season is over. It is unlikely that any romaine lettuce from the Yuma growing region is still available in people's homes, stores, or restaurants due to its 21-day shelf life.
  • Talk to your health care provider if you have symptoms of an E. coli infection and report your illness to your local health department. You can also write down what you ate in the week before you started to get sick and talk to public health investigators if they have questions about your illness.
  • Please visit the CDC website for more information on this multi-state outbreak as well as recommendations to restaurants, retailers, and clinicians.

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.

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.

Additional Info Group

Last Revised: June 1, 2018