1. Athena Institute, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, the Netherlands
2. School of Health and Medical Sciences, Örebro University, 701 82 Örebro, Sweden
3. Food Microbiology and Biotechnology Digestive System Research Unit, CIBERehd, University Hospital Vall d’Hebron,, 08035 Barcelona, Spain
4. Istituto di Microbiologia Università Cattolica S.C.,, Via Emilia Parmense 84, 29122 Piacenza, Italy
5. Departments of Pediatrics, Epidemiology and Biostatistics, University of California San Francisco (UCSF), 3333 California Street, #245, San Francisco, CA 94118, USA
6. Department of Viroscience, Erasmus Medical Center, P.O. Box 2040, 3000 CA Rotterdam, the Netherlands