1. School of Population Medicine and Public Health, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100730 , China
2. Department of Epidemiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing 100021 , China
3. National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Public Health School of Xiamen University , Xiamen 361102 , China