YL reports grants from Wellcome Trust and consulting fees from WHO and Pfizer outside the submitted work. HN reports grants from the Innovative Medicines Initiative; consulting fees from WHO, Gates Foundation, Pfizer, and Sanofi; honoraria from AbbVie; support from Sanofi for attending meetings; and honoraria for participation on advisory boards from Sanofi, Janssen, Novavax, Merck, and Resvinet outside the submitted work. HN is also a member of WHO Technical Advisory Groups on respiratory syncytial virus, which is unremunerated.