Escherichia coli is a bacterium that’s part of the normal intestinal flora of warm-blooded organisms, including humans. It’s pretty harmless most of the time, but when “fecal contamination” between different organisms occurs, it can result in a very serious illness. It took more than a year, but authorities in Colorado have traced a September 2013 E. coli outbreak to one specific food: cucumbers from Jimmy John’s sandwich shops in three towns in Colorado.

Specifically, authorities traced the outbreak to Mexican cucumbers that the chain put on salads. In the past, Jimmy John’s has also had foodborne pathogen problems with sandwich-topping raw vegetables like sprouts and lettuce. Food Safety News points out that the chain has had five different outbreaks related to bean sprouts since 2008, making us return to that whole “maybe don’t eat sprouts” thing.

Back to the cucumbers: the experts traced the cucumbers distributed to the chain and to each of the individual restaurants back to the same batch at the same source. They also confirmed that eight cases were the same strain of E. coli by testing samples of bacteria taken from patients’ stool.

The danger had passed by the time investigators were able to trace the source, but it’s useful to confirm that it was not sprouts making people sick for once, and that cucumber slices on a sandwich can be a vector to deliver E. Coli to potential victims.

Cucumbers Likely Cause of Jimmy John’s E. Coli Outbreak [Food Safety News]

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