1. State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health, Xiamen University, Xiamen City, Fujian Province, People’s Republic of China
2. Nanjing Center for Disease Control and Prevention, Nanjing, Jiangsu Province, People’s Republic of China
3. Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu Province, People’s Republic of China