Federal officials connected some of the dots in their investigation of an E. coli outbreak yesterday when they declared the outbreak over. It was one of three concurrent outbreaks linked to romaine lettuce in late 2019.
A total of 167 people infected with the outbreak strain of E. coli O157:H7 were confirmed from 27 states. Illnesses started on dates ranging from Sept. 20 to Dec. 21, 2019. Ill people ranged in age from less than 1 to 89 years, with a median age of 27. Sixty-four percent of ill people were female. Of 165 ill people with information available, more than half were so sick they had to be admitted to hospitals. Fifteen people developed hemolytic uremic syndrome (HUS), a type of kidney failure. No deaths were reported.
The Public Health Agency of Canada also reported several illnesses that were closely related genetically to the illnesses in the United States. As of Dec. 6, 2019, there were two illnesses related to the U.S. outbreak that have been identified in Canada. These individuals became ill in mid-October to early November 2019. One individual was hospitalized. Neither died. Epidemiologic, laboratory, and traceback evidence indicated that romaine lettuce from the Salinas Valley growing region in California was the likely source of this outbreak.
According to the FDA, this outbreak, a Washington state outbreak linked to leafy greens, and another multi-state outbreak shared a common denominator — a romaine lettuce supplier with ranches in Salinas, CA.
Although this grower was determined to be a common supplier for all three outbreaks based on available supply chain information, the romaine lettuce from this grower does not explain all the illnesses seen in the three outbreaks, according to the FDA and CDC. Neither agency has named the grower.
The Maryland Department of Health identified the outbreak strain of E. coli O157:H7 in an unopened package of Ready Pac Foods Bistro Chicken Caesar Salad collected from a sick person’s home in Maryland. The Wisconsin Department of Health Services identified the outbreak strain of E. coli O157:H7 in an unopened bag of Fresh Express Leafy Green Romaine collected from an ill person’s home in Wisconsin. The Salinas Valley growing region in California was the main source of the romaine lettuce in both products.
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