1. From the CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (L.D., Y.L., J.Y., G.F.G.), the National Institute for Food and Drug Control (Z.Y., P.H., Z.H., C.L.), and Beijing Keytech Statistical Technology (Z.J.), Beijing, the Hunan Provincial Center for Disease Control and Prevention, Changsha (L.G., F.L.), and Anhui Zhifei Longcom Biopharmaceutical, Hefei (L.T., F.D.) — all in China; the Child Health Department, Faculty of Medicine,...