1. Beijing Ditan Hospital, Capital Medical University, and Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China (C.C., G.G., Y.X., L.P., Q.W., L.W., Y.S., M.C., L.W., F.Y., S.Y., Y.T., Y.W., H.Z., F.Z.)
2. NHC Key Laboratory, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China (W.W., L.Z., H.W.)