Department of Pediatrics, University of California San Francisco, University of California, Los Angeles (UCLA) - Department of Pediatrics, University of California, Los Angeles (UCLA) - Division of General Internal Medicine, University of California, Los Angeles (UCLA) - Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles (UCLA) - Department of Computational Medicine, University of California, Los Angeles (UCLA) - Department of Pediatrics, Harvard University - Department of Cardiology, University of Pennsylvania - Department of Anesthesiology and Critical Care Medicine, Department of Pediatrics, University of California San Francisco, University of California, Los Angeles (UCLA) - Division of General Internal Medicine, Washington University in St. Louis - Department of Anesthesiology, Division of Pulmonary and Critical Care, University of Toronto - Department of Surgery, Harvard University - Department of Pediatrics, University of California, Los Angeles (UCLA) - Department of Pediatrics and affiliation not provided to SSRN

University of California, San Francisco (UCSF), University of Pennsylvania - Children's Hospital of Philadelphia, Department of Biostatistics and Informatics, University of Colorado, Colorado School of Public Health, Children's Hospital Colorado, Department of Pediatrics, Section of Pulmonary Medicine, University of Colorado School of Medicine, University of Utah, Department of Pediatrics, Section of Critical Care Medicine, University of Colorado School of Medicine and Children’s Hospital Colorado, Department of Pediatrics, Section of Critical Care Medicine, University of Colorado School of Medicine and Children’s Hospital Colorado, Department of Pediatrics, Section of Critical Care Medicine, University of Colorado School of Medicine and Children’s Hospital Colorado, University of Pennsylvania - Children's Hospital of Philadelphia, University of California, San Francisco (UCSF) - UCSF Medical Center, Nationwide Children’s Hospital, University of Pennsylvania - Children's Hospital of Philadelphia, University of Pittsburgh, affiliation not provided to SSRN, University of California, Los Angeles (UCLA) - Department of Pediatrics, Department of Pediatrics, Children’s National Medical Center and George Washington School of Medicine and Health Services, University of California, San Francisco (UCSF), Princeton University, University of California, San Francisco (UCSF) - Division of Infectious Diseases and Children's Hospital Colorado