1. Institute of Public Health, Heidelberg University, Im Neuenheimer Feld 130.3, Heidelberg, Germany
2. World Bank, Zambia Country Office, Atlas Mara House, Church Road, Lusaka, Zambia
3. Karolinska Institutet, Department of Public Health Sciences, Centre for Global Health, Stockholm, Sweden
4. Aidhedge, SE-102 34 Stockholm, Sweden