With another flour-related foodborne illness outbreak brewing – this time Salmonella – a bit(e) of history might be on the menu. Here is the latest one:

As of March 30, 2023, 12 people infected with the outbreak strain of Salmonella have been reported from 11 states – California, Oregon, Nebraska, Minnesota, Iowa, Missouri, Illinois, Tennessee, Ohio, Virginia and New York. Illnesses started on dates ranging from December 6, 2022, to February 13, 2023. Sick people range in age from 12 to 81 years, with a median age of 64, and 92% are female. Of 10 people with race or ethnicity information available, 8 are White, 2 are Asian, and no one reported Hispanic ethnicity. Of 12 people with information available, 3 have been hospitalized. No deaths have been reported. Investigators are working to identify specific brands of flour that are linked to illness. In the meantime, CDC always advises you not to eat raw cookie dough or cake batter.

2021 Multistage Outbreak of E. Coli O121 linked to Flour

As of July 27, 2021, 16 people infected with the outbreak strain of E. coli O121 have been reported from 12 states. Illnesses started on dates ranging from February 26, 2021 to June 21, 2021. Sick people range in age from 2 to 73 years, with a median age of 13, and 100% are female. Of 16 people with information available, 7 have been hospitalized. One person has developed a type of kidney failure called hemolytic uremic syndrome (HUS), and no deaths have been reported. FDA is conducting a traceback investigation using purchase records from locations where sick people bought cake mix to try to determine a common cake mix brand or production facility. CDC advises people not to eat raw cake batter, whether made from a mix or homemade. Eating raw cake batter can make you sick. Raw cake batter can contain harmful bacteria. Bacteria are killed only when raw batter is baked or cooked.

2018-2019 Multistate Outbreak of E coli O26 Linked to Flour

In May 2019 the CDC announced an investigation of E. coli O26 infections linked to flour produced by ADM Milling Company and sold at ALDI grocery stores. As of July 11, 2019 there were 21 outbreak associated cases reported by 9 states. Illnesses started on dates ranging from December 11, 2018 to May 21, 2019. Three people were hospitalized. No one died. In interviews, 4 ill people reported eating, licking, or tasting raw, homemade dough or batter. Investigators with the Rhode Island Department of Health collected records and flour samples at a bakery where an ill person reported eating raw dough. The bakery used Baker’s Corner All Purpose Flour from ALDI. The outbreak strain was isolated from an unopened bag of Baker’s Corner All Purpose Flour collected at the bakery. On May 23, 2019 ADM Milling Co. and ALDI recalled 5-lb. bags of Baker’s Corner All Purpose Flour. Recalled flour was sold at retail locations in Connecticut, Delaware, Massachusetts, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont and West Virginia. On June 13, 2019 King Arthur Flour, Inc. a customer of ADM announced a recall of 14,218 cases of 5-lb. bags of King Arthur Unbleached All-Purpose Flour. On June 14, 2019 another customer of ADM Milling Company, Hometown Food Company, announced a recall of 5-lb. bags of Pillsbury Best Bread Flour. On June 14, 2019 Hometown food Company, a customer of ADM Milling Co., announced a recall of Pillsbury Best Bread Flour. On June 21, 2019 Brand Castle, LLC of Bedford Heights, Ohio recalled several brands of cookie and brownie mix because the flour used in them was potentially contaminated.

2015-2016 Outbreak of E. coli O121 linked to General Mills’ Flour

In June 2016 the CDC announced that public health officials were investigating a multistate outbreak of E. coli O121 linked to flour produced at the General Mills’ Kansas City, Missouri facility. In interviews with ill persons, sixteen (76%) reported that they or someone in their household used flour in the week before they became ill. Twelve (55%)of 22 people reported using Gold Medal brand flour. On September 29, 2016 the outbreak was declared to be over. There were 63 ill people reported by 24 states. Seventeen people were hospitalized. One person developed hemolytic uremic syndrome. No one had died. Illness onset dates ranged from December 21, 2015 to September 5, 2016. The FDA identified STEC O121 in an open sample of General Mills flour collected from the homes of ill persons in Colorado, Arizona and Oklahoma. On May 31, 2016 General Mills recalled several sizes and varieties of Gold Medal Flour, Gold Medal Wondra Flour, and Signature Kitchens Flour. On July 1 General Mills expanded the recall. the recall was expanded again on July 25, 2016.

2015-2016 Multistate Outbreak of E. coli O157 Linked to Dough Mix at Pizza Ranch

In 2016 public health officials investigated an outbreak of E. coli O157 linked to consumption of products made with contaminated dough mix. A total of 13 cases were reported by 9 states. Eight were hospitalized. There were no deaths. Illness onset dates ranged from December 6, 2015 to February 9, 2016. Nine of 12 persons interviewed reported eating at one of 9 locations of Restaurant A during the week preceding illness onset. Eight ate a specific dessert pizza made through a proprietary dough mix provided by manufacturer A. The ninth patient consumed bread sticks made from the same dough mix. Eighty-eight samples of dry dough mix from five restaurant A locations where patients reported eating were collected by public health officials in 5 states. The Minnesota Department of Agriculture identified non-0157 STEC in 17 collected samples, including one Shiga toxin-1-producing non-O157 STEC isolate and six Shiga toxin 2 (stx2)-producing non-O157 STEC isolates. FDA collected 6 samples of dry dough mix from manufacturer A. All six samples tested negative for STEC O157, but one yielded an stx2 producing STEC O8:H28. All identified strains lacked known adherence factors and were therefore considered to present low health risk.

2009 Multistate Outbreak of E. coli O157:H7 Linked to Nestle Raw Refrigerated Prepackaged Cookie Dough

Eighty ill persons infected with a single strain of E. coli O157:H7 were identified in at least 31 states. At least 70 of these illnesses were confirmed by an advanced DNA test as being the same strain of E.coli O157: H7. An epidemiological study indicated a strong association between eating raw, prepackaged, cookie dough and infection; Nestle Toll House brand cookie dough was mentioned by most ill persons who had reported eating cookie dough. On June 29, 2009, the Food and Drug Administration announced that they had found E.coli O157:H7 in a package of cookie dough that had been collected from a Nestle plant on June 25. The strain identified from the package was different from the outbreak strain. E.coli O157:H7 infection had not been previously associated with eating raw cookie dough. The strain of E.coli O157:H7 associated with this outbreak had been associated with earlier outbreaks going back to February, 2005. Although the investigation found no conclusive evidence that contaminated flour was the outbreak source, contaminated flour remained the prime suspect in this outbreak. A single, large purchase of contaminated flour could have been used to manufacture multiple lots and varieties of dough over time as was consistent with the variety of UBD codes on product packages from ill consumers.