Yang Sun1, Yinzhong Shen2, Hongzhou Lu3. 1. Department of Infectious Diseases, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China; Institute of Medicine Science, Shanghai Tongji Hospital, Shanghai Tongji University School of Medicine, Shanghai 200065, China. 2. Department of Infectious Diseases, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China. 3. Department of Infectious Diseases, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China. Email: luhongzhou@fudan.edu.cn.