1. State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
2. Department of Disease Control, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom.
3. Institute of Population Research, Peking University, Beijing, China.
4. School of Public Health and Management, Guangzhou University of Chinese Medicine
5. Department of Science and Technology Studies, University College London, London, UK
6. State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China