1. Department of Chemical Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, PR China
2. Department of Medicine, Chittagong Medical College Hospital, Chittagong, 4217, Bangladesh
3. Nuffield Department of Clinical Medicine, Centre for Tropical Medicine & Global Health, University of Oxford, Old Road campus, Roosevelt Drive, Headington, Oxford, OX3 7FZ, UK
4. Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Rajthevee, Bangkok, 10400, Thailand