GRAND RAPIDS, Mich. (WOOD/WJW) — Wendy’s is removing romaine lettuce from their sandwiches after half of the patients in the Michigan E. coli outbreak reported eating at the restaurant.

While no specific food as been confirmed to be source of the outbreak, the state health department said that more than 55% of the patients in cases in Michigan reported consuming food — specifically sandwiches with romaine lettuce — at Wendy’s restaurant locations.

The restaurant is removing the lettuce from locations in that region for the time being, as precaution. Wendy’s uses a different type of romaine lettuce in its salads.

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.

In a Friday press release, MDHHS said that there were 43 confirmed shiga toxin E. coli cases in the state. The illnesses happened in late July through early August in 18 jurisdictions. Cases were reported in Allegan, Branch, Clinton, Genesee, Gratiot, Jackson, Kent, Macomb, Midland, Monroe, Muskegon, Oakland, Ogemaw, Ottawa, Saginaw Washtenaw, and Wayne counties.

The E. coli outbreak has been affecting people ages 6 to 94 years old. Fifty-six percent of people with the infection have been hospitalized. Four cases of hemolytic uremic syndrome, a complication related to shiga toxin E. coli infections, have also been identified.

Symptoms of E. coli infection typically appear three to four days after the exposure and usually improve in five to seven days.

MDHHS reminds Michigan residents to seek medical attention if they experience symptoms such as severe stomach cramps, diarrhea, vomiting or other gastrointestinal distress. It also urged people to take proper precautions when they are handling food.

For more information on E. coli, visit the USDA website on protection from foodborne illness or the CDC website on prevention. Find food safety information on the Michigan Department of Agriculture and Rural Development website.