1. French Institute for Public Health Surveillance (Institut de veille sanitaire), St Maurice, France
2. Regional Office of the French Institute for Public Health Surveillance, Caen, France
3. Institut Pasteur, National Reference Centre for Escherichia coli and Shigella, Paris, France
4. University Hospital of Caen, Neurology department, Caen, France
5. University Hospital of Caen, Nephrology department, Caen, France
6. Laboratory associated to the National Reference Centre for Escherichia coli and Shigella, Robert Debré Hospital, Paris, France