Bagged-Salad_406x250Health officials in England are tracking an outbreak of E. coli O157 linked to prepackaged salad that has sickened 38 people. The Verocytotoxigenic E. coli (VTEC) cases were first identified in early August 2015 by whole genome sequencing. As of Sept. 3, the cluster includes 38 confirmed cases, with one additional probable case and four possible cases for which whole genome sequencing results are pending. Onset dates for confirmed and probable cases range from July 29 to Aug. 12, 2015. Cases are widely distributed across England, with one in Wales but none identified in Scotland to date. In England, the majority of confirmed cases have been reported from Anglia and Cheshire and Merseyside (seven each). Most of those sickened are females and are ages 18 to 73 years. Analysis of enhanced VTEC questionnaires has shown that 33 victims had been exposed to prepackaged salad and that 19 of them had purchased the product at the same supermarket chain. A focused survey carried out with 24 of the confirmed cases indicated that the most common exposures were to two salad products from one supermarket chain which share one ingredient. Traceback has been initiated, and one packer/distributor supplied by three farms has been identified. Samples are being collected from the supermarket chain outlets visited by those sickened, the distributor/packer, and from the supply farms. Investigations to determine the exact source and the cause of contamination are ongoing.

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