1. National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
2. Qinghai Provincial Institute of Endemic Disease Control and Prevention, Xining, China
3. Qilian County Center for Disease Control and Prevention, Haibei Tibetan Autonomous Prefecture, Qilian, China
4. School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China