INDIANAPOLIS — More than 80 illnesses have now been reported in a multi-state E. coli outbreak from an unknown source.

The Centers for Disease Control provided an update Thursday in its investigation into the outbreak. 84 illnesses have been reported so far, an increase of 47 cases since Friday. So far, 38 have been hospitalized and 8 people in Michigan have developed a type of kidney failure called hemolytic uremic syndrome. No deaths have been reported.

The four states the CDC listed as being affected are Michigan, Ohio, Pennsylvania and Indiana. Michigan is reporting the most cases at 53. Ohio has reported 23 cases, Indiana reports six, and Pennsylvania reports two cases.

The CDC says most people infected with Shiga toxin-producing E. coli experience severe stomach cramps, diarrhea, and vomiting three to four days after swallowing the bacteria.

While most people recover without treatment within 5 to 7 days, some people may develop a type of kidney failure and need to be hospitalized.

The CDC said the true number of such people in the outbreak is likely higher than the reported number, and the outbreak may not be limited to Indiana, Ohio, Michigan and Pennsylvania. This is because some of the recent illnesses have not been reported to PulseNet, as it usually takes three to four weeks to determine if a person is part of an outbreak. Other people may recover without medical care so they are not tested.

Sick people range in age from 5 to 94 years, with a median age of 24 years. A slight majority of those sickened are male. Illnesses started on dates ranging July 26 to August 9.

While a specific food source has yet to be confirmed as the source of the outbreak, many of those sickened reported eating sandwiches with romaine lettuce at Wendy’s restaurants in Indiana, Michigan, Ohio, and Pennsylvania

Among 62 people interviewed, 84% reported eating at a Wendy’s restaurant in the week before their illness started. 17 people were able to provide detailed information about what they ate at Wendy’s. All but two reported eating romaine lettuce served on burgers and sandwiches.

Health officials are still trying to determine if the romaine lettuce is the source of the outbreak. As a precautionary measure, Wendy’s is removing the romaine lettuce in the region. Wendy’s released the following statement:

“We are fully cooperating with public health authorities on their ongoing investigation of the regional E. coli outbreak reported in certain midwestern states. While the CDC has not yet confirmed a specific food as the source of that outbreak, we are taking the precaution of removing the sandwich lettuce from restaurants in that region. The lettuce that we use in our salads is different, and is not affected by this action. As a company, we are committed to upholding our high standards of food safety and quality.“

The CDC is not advising that people avoid eating at Wendy’s restaurants or stop eating romaine lettuce. The latest information does not indicate that romaine lettuce sold in grocery stores, served in other restaurants, or in people’s homes is linked to this outbreak.

Anyone with E. coli symptoms to should report it to their local or state government. Call your healthcare provider right away if you have severe E. 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.

The CDC asks anyone with symptoms to help them solve the 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.