The U.S. Food and Drug Administration issued a warning to Jimmy John’s Tuesday, listing five bacterial outbreaks linked to the brand’s clover sprouts and cucumbers.

Four of the outbreaks concerned E. coli while the other involved Salmonella. The issue dates back as far as April 2012, when 29 people from 11 states were infected with a strain of E. coli. There were also reported outbreaks in October 2013, August 2014, February 2018, and as recently as November/December 2019.  

During the 2019 outbreak, 22 people in Iowa were infected with E. Coli. Of the 20 interviewed by the Iowa Department of Public Health, all recently ate at a Jimmy John’s. The department tested the chain’s clover sprouts, and found that they were the cause of the outbreak.

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Sprouts were the cause of four of the five outbreaks. In October 2013, eight people in Colorado were infected with E. Coil, and each said they ate a sandwich with raw cucumbers at one of three Jimmy John’s in Denver.

In August 2014, 19 were infected with E. Coli across Idaho, Montana, Michigan, Utah, California, and Washington. An FDA investigation concluded that most contracted the infection from eating clover sprouts at a Jimmy John’s. In February 2018, 10 people were infected with salmonella across Illinois, Minnesota, and Wisconsin. Of those, eight dined at a Jimmy John’s, and said they ate raw sprouts.

“Taken together, these outbreaks, which spanned over the past seven years and impacted no fewer than 17 states, demonstrate the corporate-wide supplier control mechanisms you have in place for receiving fresh produce are inadequate,” the FDA stated in the letter.

The FDA said that Jimmy John’s claimed to implement corrective action after the 2012 and 2019 outbreaks, but the brand did not provide the administration with any information showing that “long-term, sustainable corrections have been implemented throughout your organization to prevent this violation from recurring in the future.”

Jimmy John’s President James North told CNN Tuesday that restaurants have removed sprouts indefinitely.

The FDA acknowledged that Inspire Brands, the chain’s parent, decided in December to destroy all sprouts in Iowa restaurants, but it also noted that “neither you nor your parent company proposed any corrective actions to prevent these, or other Jimmy John’s restaurants, from receiving adulterated produce, specifically sprouts.”

Jimmy John’s has 15 days to respond with specific ways in which it will prevent adulterated food from reaching its restaurants in the future.