1 Intensive Care Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam.
2 Intensive Care Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam; Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam.
3 Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam; Department of Tropical Medicine, University of Oxford, UK.
4 Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam; Department of Medicine, Imperial College London, UK. Electronic address: syacoub@oucru.org.