1. Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, P. R. China
2. Department of Laboratorial Science and Technology & Vaccine Research Center, School of Public Health, Peking University, Beijing, P. R. China
3. Institute for Immunization and Prevention, Inner Mongolia Center for Disease Control and Prevention, Hohhot City, People’s Republic of China
4. Institute for Immunization and Prevention, Suzhou Center for Disease Control and Prevention, Suzhou, China
5. Department of Infectious Disease, Guizhou Provincial Center for Disease Control and Prevention, Guiyang, China
6. Institute for Immunization and Prevention, Beijing Center for Disease Prevention and Control, Beijing Research Center for Preventive Medicine, Beijing, China
7. Key Laboratory of Epidemiology of Major Diseases, Ministry of Education, Peking University, Beijing, China
8. Center for Infectious Diseases and Policy Research & Global Health and Infectious Diseases Group, Peking University, Beijing, P. R. China