1. 1MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
2. †Present address: Respiratory Medicine Unit, NIHR Biomedical Research Centre, Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK.
3. 2Division of Pediatric Infectious Diseases, Department of Pediatrics, Chang Gung Children’s Hospital, Taoyuan City, Taiwan, ROC
4. 3Crick Worldwide Influenza Centre, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK