Sprouts have been called one of ten riskiest foods. They have a known, and well recognized, association with bacterial pathogens, frequently salmonella, E. coli O157, and listeria monocytogenes. Regardless of whether sprouts have been accurately designated one of the riskiest foods you can eat, they have undoubtedly caused their fair share of foodpoisoning illnesses and outbreaks.
Since 1990, raw or slightly cooked sprouts have caused an estimated 2,166 illnesses, through 33 outbreaks (actually – 37 outbreaks, 2,273 illnesses). See list of sprout outbreaks since 1990. The U.S. Food and Drug Administration estimates that sprout-link outbreaks account for 40 per cent of all food-borne illness associated with produce.
Sprouts have also been linked to very large outbreaks. From February through May of 2009, the CDC counted 235 confirmed victims of a Salmonella Saintpaul outbreak linked to alfalfa sprouts. Nebraska was the hardest hit state by far, with 111 confirmed illnesses, many of whom consumed alfalfa sprouts on sandwiches from Jimmy John’s restaurants. South Dakota had the second most illnesses with 38.
Investigating health authorities ultimately determined that sprout seeds distributed by a major seed distribution company called Caudill Seed (Louisville , KY) had been contaminated with Salmonella.
The outbreak occurred in two phases. The first phase, causing illness primarily in the midwest, occurred in February and March 2009, and the contaminated sprouts were grown by CW Sprouts, an Omaha Nebraska company. The chlorine treatment methods used by CW Sprouts were inadequate to eliminate the bacteria from the contaminated seeds that Caudill Seed had distributed to CW.
The second phase of the outbreak occurred shortly after the first, causing Salmonella infection by genetically indistinguishable bacteria from the CW Sprouts phase of the outbreak. But CW Sprouts did not distribute to many of the states affected by the second phase. The sprouts implicated in the second phase had been grown by multiple sprout growers from seeds produced and sold by Caudill Seed. In fact, the seeds in both phases of this large outbreak came from the same lot (032) of Caudill’s seeds.