1. Oxford University Clinical Research Unit, 78 Giai Phong, Hanoi, Vietnam
2. Hanoi Medical University, 1 Ton That Tung, Hanoi, Vietnam
3. National Hospital for Tropical Diseases, 78 Giai Phong, Hanoi, Vietnam
4. MRC Unit The Gambia at The London School of Hygiene & Tropical Medicine, Fajara, The Gambia
5. Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK