1 Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam.
2 Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam; Centre for Tropical Medicine and Global Health, University of Oxford, Nuffield Department of Medicine Research Building, Headington, Oxford OX3 7FZ, UK.
3 Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam; Centre for Tropical Medicine and Global Health, University of Oxford, Nuffield Department of Medicine Research Building, Headington, Oxford OX3 7FZ, UK. Electronic address: [email protected].