1. From Aarhus University Hospital, Aarhus, Denmark (L.O., N.B.S.); Vaccine Research Center, University of Tampere Medical School, Tampere, Finland (T.V.); Pfizer Vaccine Clinical Research and Development (J.A., J.J.E.) and Pfizer Vaccine Research and Development (K.U.J., A.S.A., T.R.J., S.L.H., R.O.), Pearl River, NY; Pfizer Vaccine Clinical Research and Development, Hurley, United Kingdom (J.B.); Research Institute of the McGill University Health Center, Montreal (B.J.W.); Senders Pediatrics, South Euclid...