The FDA sent a warning letter to Jimmy John's President James North implicating the restaurant chain in a series of E. coli outbreaks. The restaurant will no longer offer sprouts on its menu as a precaution for the future.

"The evidence demonstrates that your corporation, through your franchised Jimmy John's restaurants, engaged in a pattern of receiving and offering for sale adulterated fresh produce, specifically clover sprouts and cucumbers," wrote the FDA.

Five incidences affecting “no fewer than 17 states” were investigated, and all linked Jimmy John’s to either E. coli or salmonella.

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The most recent outbreak happened in Iowa in 2019, which affected 22 people. Out of the 20 ill who were interviewed, 100% of them had eaten at Jimmy John’s.

"15 Jimmy John's restaurants received clover sprouts during the period of interest. As further confirmation that sprouts served at your restaurants were the outbreak vehicle, samples of sprouts and sprout irrigation water collected by the firm that supplied the Jimmy John's restaurants yielded a strain of E. coli O103 that was highly related to the outbreak strain," the FDA wrote.

Four other instances spanning seven years were outlined in the warning letter.

All cases involved the sandwich chain. In 2018, 10 people experienced salmonella across the Midwest, 19 people were infected with E. coli across the Western U.S. in 2018, eight people in Colorado became ill with E. coli in 2013, and 29 people from 11 states fell victim to E. coli in 2012.

Most of those interviewed told the CDC they had consumed sprouts at a Jimmy John’s restaurant in seven days before falling ill.

North told USA Today that sprouts have been removed from restaurants across the nation until further notice.

"This removal was out of an abundance of caution and was not initiated by any known, immediate threat," he said.

The FDA also sent Sprouts Unlimited Wholesale Foods a warning as the supplier involved in the 2019 Iowa E. coli outbreak.