CDC Investigation Notice Update: CDC Updates Number of People Ill in E. coli Outbreak with Unknown Source

A CDC investigation notice update regarding a multistate outbreak of E. coli O157 infections is now live:

Key points:

  • Since the last update on August 19, 2022, 47 more illnesses have been reported to CDC.
  • 84 people infected with the outbreak strain of coli O157 have been reported to CDC from 4 states: Indiana (6), Michigan (53), Ohio (23), and Pennsylvania (2).
  • 38 people have been hospitalized, including 8 people in Michigan who have a type of kidney failure called hemolytic uremic syndrome. No deaths have been reported.
  • A specific food has not yet been confirmed as the source of this outbreak, but most sick people reported eating burgers and sandwiches with romaine lettuce at Wendy’s restaurants before getting sick.
    • Among 62 people interviewed, 52 (84%) reported eating at a Wendy’s restaurant in the week before their illness started.
    • Of 17 people with detailed information about what they ate at Wendy’s, 15 (88%) reported eating romaine lettuce served on burgers and sandwiches.
    • The Wendy’s restaurants where sick people ate are in Indiana, Michigan, Ohio, and Pennsylvania.
  • Based on the information collected so far, Wendy’s has taken the precautionary measure of removing the romaine lettuce being used in sandwiches from restaurants in that region. Wendy’s uses a different type of romaine lettuce for salads.
  • CDC is not advising that people avoid eating at Wendy’s restaurants or that people stop eating romaine lettuce.
    • At this time, there is no evidence to indicate that romaine lettuce sold in grocery stores, served in other restaurants, or in people’s homes is linked to this outbreak.
  • Investigators are working to confirm whether romaine lettuce is the source of this outbreak, and whether romaine lettuce served at Wendy’s restaurants was served or sold at other businesses.

What You Should Do:

  • Call your healthcare provider right away if you have severe coli symptoms, such as diarrhea that lasts for more than 3 days or diarrhea that is accompanied by a fever higher than 102˚F, bloody diarrhea, or so much vomiting that you cannot keep liquids down and are not peeing much.
  • If you have symptoms of coli, help us solve this outbreak:
    • Write down what you ate in the week before you got sick.
    • Report your illness to your local or state health department.
    • Answer public health officials’ questions about your illness.

About E. coli:

  • Symptoms of Shiga toxin-producing coli (STEC) infection vary for each person, but often include severe stomach cramps, diarrhea (often bloody), and vomiting. Some people may have a fever, which usually is not very high (less than 101˚F/38.5˚C).
  • Most people get better within 5 to 7 days. Some infections are very mild, but others are severe or even life-threatening.
  • Most people with a STEC infection start feeling sick 3 to 4 days after eating or drinking something that contains the bacteria. However, illnesses can start anywhere from 1 to 10 days after exposure.

If you have questions about cases in a particular state, please call that state’s health department.


CDC works 24/7 protecting America’s health, safety and security. Whether disease start at home or abroad, are curable or preventable, chronic or acute, or from human activity or deliberate attack, CDC responds to America’s most pressing health threats. CDC is headquartered in Atlanta and has experts located throughout the United States and the world.