1. Médecins Sans Frontières, Médecins Sans Frontières, Noma Children's Hospital, Mamarun Nufawa, Sokoto, Nigeria Sokoto, Nigeria
2. Department of Public Health Medicine, University of Cape Town, Anzio Rd, Observatory, Cape Town, South Africa
3. Médecins Sans Frontières, Plantage Middenlaan 14, 1018 DD, Amsterdam, The Netherlands
4. Department of Medical Microbiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
5. Centre for Infectious Disease Epidemiology and Research, School of Public Health and Family Medicine, University of Cape Town, Anzio Rd, Observatory, Cape Town, South Africa
6. Médecins Sans Frontières, Lower Ground Floor, Chancery Exchange, 10 Furnival Street, London, UK
7. Médecins Sans Frontières—Operational Centre Brussels, Medical Department, 68 Rue de Gasperich, 1617, Luxembourg Operational Research Unit (LuxOR)
8. Division of Social and Behavioural Sciences, School of Public Health and Family Medicine, University of Cape Town, Anzio Road, Observatory, Cape Town, South Africa