Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC), Peking University - Department of Health Policy and Management, Sichuan Center for Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Suqian City Center for Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC), Chinese Center for Disease Control and Prevention (China CDC) - National Immunization Program and Peking University - School of Public Health