While the Centers for Disease Control and Prevention initially said 37 people in Indiana, Michigan, Ohio and Pennsylvania were sickened from eating lettuce in the sandwiches, that number has since jumped to more than 100, the outlet said.
Wendy's said it's taking precautions by throwing out and replacing the lettuce.
More than 98 reports were received in Michigan for the month of August, compared to this time last year when the number was 20, the state's health department said. Forty-three of those cases were linked to Wendy's, the other 55 have results pending.
Three Michigan residents and five Ohio residents sued the fast food chain in the last week over E. coli.
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