1 Paediatric Infectious Diseases Research Group, Institute for Infection and Immunity, St George's University of London, London, UK; Institute for Medical Microbiology and Hospital Hygiene, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany. Electronic address: malte.kohnsvasconcelos@med.uni-duesseldorf.de.
2 Paediatric Infectious Diseases Unit, Department of Paediatrics, Hospital Universitario 12 de Octubre, Madrid, Spain; Paediatric Research and Clinical Trials Unit, Instituto de Investigación Sanitaria Hospital 12 de Octubre and Translational Research Network in Paediatric Infectious Diseases, Fundación para la Investigación Biomédica del Hospital 12 de Octubre, Madrid, Spain.
3 Department of Paediatric Cardiology, Pulmonology and Intensive Care Medicine, University Children's Hospital Tübingen, Tübingen, Germany.
4 Paediatrics Department, Hospital Universitario Infanta Sofía, Paediatrics Research Group, Universidad Europea de Madrid, Madrid, Spain.
5 Paediatric Infectious Diseases Research Group, Institute for Infection and Immunity, St George's University of London, London, UK; Department of Infectious Diseases and Vaccinology, University of Basel Children's Hospital, Basel, Switzerland; Fondazione Penta Onlus, Padova, Italy.