title: Shopper cards data and storage practices for the investigation of an outbreak of Shiga-toxin producing Escherichia coli O157 infections.
abstract: BACKGROUND
  An outbreak of shiga-toxin producing Escherichia coli infections occurred in southwest France in June 2012. The outbreak was investigated to identify the source of infection, and guide control measures.
  
  
  METHODS
  Confirmed outbreak cases were patients who developed bloody diarrhoea or haemolytic uremic syndrome (HUS) between 28 May and 6 July 2012, with E. coli O157 isolates showing indistinguishable patterns on pulse field gel electrophoresis (PFGE). A standardized questionnaire was administered to patients to document food consumption and other risk exposures. Their purchase was checked through their supermarket shopper card data.
  
  
  RESULTS
  Six patients (four with HUS and two with bloody diarrhea) were confirmed outbreak cases. Fresh ground beef burgers from one supermarket were the only common food exposure, identified by interviews and shopper card data. The PFGE profile of shiga toxin-producing E. coli O157 isolated from the suspected beef burgers was identical to those from the human cases. The suspected beef burgers were no longer on sale at the time of investigation but three patients confirmed as outbreak cases had deep-frozen some at home.
  
  
  CONCLUSIONS
  Shopper card data was particularly useful to obtain precise and reliable information on the traceability of consumed food. Despite the expired use-by date, a recall was issued for the beef burgers. This contributed to preventing other cases among consumers who had deep-frozen the beef burgers.
authors.affiliation: Institut de veille sanitaire, département des maladies infectieuses, 12, rue du Val-d'Osne, 94415 Saint-Maurice cedex, France. Electronic address: asbarret@hotmail.fr.
authors.forename: A-S
authors.initials: AS
authors.lastname: Barret
authors.forename: M
authors.initials: M
authors.lastname: Charron
authors.forename: P
authors.initials: P
authors.lastname: Mariani-Kurkdjian
authors.forename: M
authors.initials: M
authors.lastname: Gouali
authors.forename: E
authors.initials: E
authors.lastname: Loukiadis
authors.forename: B
authors.initials: B
authors.lastname: Poignet-Leroux
authors.forename: A
authors.initials: A
authors.lastname: Godron
authors.forename: G
authors.initials: G
authors.lastname: Gault
authors.forename: M
authors.initials: M
authors.lastname: Faure
authors.forename: A
authors.initials: A
authors.lastname: Mailles
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D002417:Cattle; D015925:Cryopreservation; D004196:Disease Outbreaks; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D019453:Escherichia coli O157 / Q000235:genetics / Q000302:isolation & purification*; D005506:Food Contamination; D005519:Food Preservation; D061353:Food Storage; D005602:France / Q000453:epidemiology; D005798:Genes, Bacterial; D006463:Hemolytic-Uremic Syndrome / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D006801:Humans; D008461:Meat Products / Q000382:microbiology*; D062486:Public Health Surveillance / Q000379:methods*; D011996:Records
keywords: Carte de fidélité; Conservation des aliments; Escherichia coli producteur de Shiga-toxines; Hemolytic uremic syndrome; Outbreak; Shiga-toxin producing Escherichia coli; Shopper card; Storage practices; Syndrome hémolytique et urémique; Épidémie