University of Gothenburg, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, Murdoch University, World Health Network Long Covid Expert Advisory Group, McGill University, Faculty of Engineering, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, University of Derby, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, Long Covid Support, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, The University of Manchester - Manchester University NHS Foundation Trust, University of Adelaide, University of New South Wales (UNSW) - Biosecurity Research Program, CEO & Founder Long Covid Kids, Imperial College London, Murdoch University - The Centre for Computational and Systems Medicine, Independent, World Health Network Long Covid Expert Advisory Group, World Health Network Long Covid Expert Advisory Group, Westmead and Blacktown Hospitals and World Health Network Long Covid Expert Advisory Group

Russian Academy of National Economy and Public Administration under the President of the Russian Federation (RANEPA) - Laboratory of Health Economics, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Tareev Clinic of Internal Diseases, I.M. Sechenov First Moscow State Medical University - Clinic of Pulmonology, I.M. Sechenov First Moscow State Medical University - Department of Internal Medicine №1, Moscow Research and Clinical Center for Neuropsychiatry, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Clinical Immunology and Allergology, University of Pisa - Department of Clinical and Experimental Medicine, Otto von Guericke University Magdeburg - Institute of Social Medicine and Health Systems Research, University of Leipzig - Pediatric Epidemiology, Universidad de la Sabana, University of Amsterdam - Department of Pediatric Pulmonology, I.M. Sechenov First Moscow State Medical University, I.M. Sechenov First Moscow State Medical University, I.M. Sechenov First Moscow State Medical University - World-Class Research Center, Government of the Russian Federation - Russian Medical Academy of Continuous Professional Education, ZA Bashlyaeva Children's Municipal Clinical Hospital, Government of the Russian Federation - Russian Medical Academy of Continuous Professional Education, N. I. Pirogov Russian National Research Medical University (RSMU), I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, I.M. Sechenov First Moscow State Medical University - Department of Paediatrics and Paediatric Infectious Diseases, University of Oxford - Nuffield Department of Medicine, University of Oxford - International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC), MRC-University of Glasgow Centre for Virus Research, University of Colorado at Denver - Department of Pediatrics, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, University of Liverpool - Health Protection Research Unit in Emerging and Zoonotic Infections, Imperial College London - Inflammation, Repair and Development Section, University of Oxford - Nuffield Department of Medicine, Johns Hopkins University - Outcomes After Critical Illness and Surgery (OACIS) Research Group, I.M. Sechenov First Moscow State Medical University, I.M. Sechenov First Moscow State Medical University, N. I. Pirogov Russian National Research Medical University (RSMU), Imperial College London and affiliation not provided to SSRN

Universitat Politècnica de Catalunya (UPC Barcelona Tech) - Department of Physics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP), Carol Davila University of Medicine and Pharmacy, National Institute for Mother and Child Health, Royal Hospital for Children and Young People, University of Bristol - Population Health Sciences, Barnaspitali Hringsins Children's Hospital, Generalitat de Catalunya - Department of Health, Generalitat de Catalunya, Children's Hospital Vall d'Hebron, Children's Hospital Vall d'Hebron, Polytechnic University of Catalonia (UPC) - Computational Biology and Complex Systems (BIOCOM-SC), Leicester University, Autonomous University of Barcelona - Paediatric Infectious Diseases and Immunodeficiencies Unit, University of Edinburgh and Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health

Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital, Bambino Gesù Children's Hospital and Bambino Gesù Children's Hospital - Academic Department of Pediatrics (DPUO)

Leicester University, University of Leicester, affiliation not provided to SSRN, Imperial College London, Padua University and Hospital, Government of the United Kingdom - Institute of Cancer Research, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, University of Padua - Department of Woman’s and Child’s Health, Imperial College London - Department of Epidemiology and Biostatistics, Mater Dei Hospital, affiliation not provided to SSRN, Erasmus University Rotterdam (EUR) - Department of General Paediatrics, Imperial College London, affiliation not provided to SSRN, Erasmus University Rotterdam (EUR) - Department of General Paediatrics, Hôpital Robert Debré and Imperial College London - Section of Paediatric Infectious Disease

Imperial College London - Section of Paediatric Infectious Disease, Government of the United Kingdom - Institute of Cancer Research, Mater Dei Hospital, Imperial College London, affiliation not provided to SSRN, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, University of Padua - Department of Woman’s and Child’s Health, Imperial College London - Department of Epidemiology and Biostatistics, Imperial College London, Ospedale Paediatrico Meyer Firenze, Leicester University, Karolinska Institutet - Department of Global Public Health, Jean Verdier Hospital, University College Dublin (UCD) - Women’s and Children’s Health, Louis Mourier Hospital, Erasmus University Rotterdam (EUR) - Department of General Paediatrics, affiliation not provided to SSRN, Paracelsus Medical University Salzburg, Tallaght University Hospital, Children’s Health Ireland, University of Szeged - Albert-Szent Györgyi Medical Centre, Hospital Universitario Cruces, Medical University of Vienna, Sorbonne University - Pediatric Emergency Deparment, Government of the United Kingdom - Birmingham Women’s and Children’s NHS Foundation Trust, Ludwig Maximilian University of Munich (LMU), Lithuanian University of Health Sciences, Medical University of Graz, affiliation not provided to SSRN, University of the West of England (UWE), Coimbra Hospital and University Centre (CHUC), Hospital Dr. Fernando da Fonseca, Alder Hey Children's NHS Foundation Trust, Ondokuz Mayis University, Riga Stradins University, Centro Hospitalar Tondela-Viseu, Association Clinique et Thérapeutique Infantile du Val-de-Marne (ACTIV), Karolinska Institutet, Hacettepe University Medical School, Mersin City Training and Research Hospital, Barnaspitali Hringsins Children's Hospital, Hospital Río Hortega de Valladolid, Padua University and Hospital, Erasmus University Rotterdam (EUR) - Department of General Paediatrics, Erasmus University Rotterdam (EUR) - Department of General Paediatrics and Hôpital Robert Debré

- Section of Pediatrics, University of Naples Federico II, University of Naples Federico II, University of Palermo, Sapienza University of Rome - Department of Maternal, Infantile, and Urological Sciences, Santobono-Pausilipon Children's Hospital, Azienda Ospedaliero Universitaria Consorziale Policlinico di Bari, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, Bambino Gesù Children's Hospital, S. Maria della Speranza Hospital of Battipaglia, University of Florence - Meyer Children’s Hospital, University of Pavia, University of Campania Luigi Vanvitelli, University of Palermo, University of Naples Federico II and - Department of Translational Medical Sciences

Heidelberg University - University Medical Center Mannheim, - Clinical Hospital San Carlos, Heidelberg University - First Department of Medicine, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Instituto de Investigación, Sanitaria del Hospital Clínico San Carlos (IdISSC), Hospital Clínico Universitario Virgen de la Victoria, Departamento de Cardiología, Hospital Clínico Universitario de Valladolid, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Instituto de Investigación, Sanitaria del Hospital Clínico San Carlos (IdISSC), Hospital Nuestra Señora de América, Hospital Universitario Guadalajara, Centro Cardiologico Monzino, IRCCS, Universidade de Santiago de Compostela - Cardiology Department, Azienda Ospedaliero-Universitaria Consorziale Policlinico Di Bari, Hospital Universitario Getafe, Hospital General del norte de Guayaquil IESS Los Ceibos, San Luigi Gonzaga University Hospital, Orbassano and Rivoli Infermi Hospital, Hospital Virgen del Mar, University of Turin - Department of Cardiology, Hospital IMED, Hospital Clínico de Valencia, INCLIVA, Hospital Clínico Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Fondazione Policlinico Universitario A. Gemelli IRCCS - Department of Woman and Child Health and Public Health, University Hospital Joan XXIII, Heidelberg University - Department of Medical Statistics and Biomathematics, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Instituto de Investigación, Sanitaria del Hospital Clínico San Carlos (IdISSC), Instituto Cardiovascular, Hospital Clínico San Carlos and Heidelberg University - First Department of Medicine