1. China Center for Health Development Studies, Peking University, No 38, Xueyuan Road, Haidian District, 100191 Beijing, China
2. Centre for History in Public Health, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1E 7HT, UK
3. Department of Global Health and Development, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1E 7HT, UK