1. Department of Microbiology and Infection Control; Statens Serum Institut; Copenhagen Denmark
2. Department of Paediatrics; Hvidovre University Hospital; Copenhagen Denmark
3. H.C. Andersen's Children's Hospital; University of Odense; Odense Denmark
4. Department of Gastroenterology; Hvidovre University Hospital; Copenhagen Denmark
5. Department of Clinical Microbiology; Hvidovre University Hospital; Copenhagen Denmark