University of Basel - Swiss Tropical and Public Health Institute, University of Basel - Swiss Tropical and Public Health Institute, University of Basel, University of Basel, University of Basel, University of Basel, University of Basel, HFR Fribourg Cantonal Hospital - Department of Pediatrics, University of Zurich, HFR Fribourg Cantonal Hospital - Department of Pediatrics, University of Basel - Swiss Tropical and Public Health Institute and University of Basel