1 MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College, London, UK.
2 Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
3 Department of Global Health, Boston University School of Public Health, Boston, MA, USA.
4 Avencion Limited, Lusaka, Zambia.
5 Department of Biomedical Sciences, School of Health Sciences, University of Zambia, Lusaka, Zambia.
6 Zambia National Public Health Institute, Lusaka, Zambia.
7 Manicaland Centre for Public Health Research, Biomedical Research and Training Institute, Harare, Zimbabwe.
8 Carlo F. Dondena Centre for Research on Social Dynamics and Public Policy, Bocconi University, Milan, Italy.
9 Max Planck Institute for Demographic Research, Rostock, Germany.
10 Department of Social and Political Science, Bocconi University, Milano, Italy.
11 Centers for Disease Control and Prevention, Lusaka, Zambia.
12 Zambia Ministry of Health, Lusaka, Zambia.
13 MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College, London, UK. patrick.walker06@imperial.ac.uk.