1. Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Centre for Disease Control and Prevention, 155 Changbai Road, Changping District, Beijing, 102206, China.
2. West China School of Public Health, Sichuan University, Chengdu, China.
3. Sinosoft Company, Beijing, China.
4. Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada.
5. International Field Epidemiology Training Programme, Ministry of Public Health, Nonthaburi, Thailand.
6. Research School of Population Health, The Australian National University, Canberra, Australia.
7. School of Public Health and Social Work, Queensland University of Technology, Brisbane, Australia.