Shopper cards data and storage practices for the investigation of an outbreak of Shiga-toxin producing Escherichia coli O157 infections.
INTRODUCTION
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.


CONCLUSION
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.
['Barret|A-S|AS|', 'Charron|M|M|', 'Mariani-Kurkdjian|P|P|', 'Gouali|M|M|', 'Loukiadis|E|E|', 'Poignet-Leroux|B|B|', 'Godron|A|A|', 'Gault|G|G|', 'Faure|M|M|', 'Mailles|A|A|', '|||']
D000818:Animals D015373:Bacterial Typing Techniques D002417:Cattle D015925:Cryopreservation D004196:Disease Outbreaks D004927:Escherichia coli Infections D019453:Escherichia coli O157 D005506:Food Contamination D005519:Food Preservation D061353:Food Storage D005602:France D005798:Genes, Bacterial D006463:Hemolytic-Uremic Syndrome D006801:Humans D008461:Meat Products D062486:Public Health Surveillance D011996:Records
Shopper card Storage practices Outbreak Shiga-toxin producing Escherichia coli Carte de fidélité Conservation des aliments Escherichia coli producteur de Shiga-toxines Hemolytic uremic syndrome Syndrome hémolytique et urémique Épidémie