1. Department of Epidemiology, Ministry of Education Key Laboratory of Public Health Safety, School of Public Health, Fudan University, Shanghai, China
2. Department of Immunization Planning, Minhang District Center for Disease Control and Prevention, Shanghai, China
3. Department of Immunization Planning, Jiading District Center for Disease Control and Prevention, Shanghai, China
4. Institute of Immunization Planning, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, China