1. Dengue Unit, National Hospital of Sri Lanka, Colombo, Sri Lanka
2. Dengue Research Group, Colombo, Sri Lanka
3. Department of Medicine, Base Hospital, Panadura, Sri Lanka
4. Department of Medicine, National Hospital of Sri Lanka, Colombo, Sri Lanka
5. Department of Surgery, Faculty of Medicine, University of Colombo, 25 Kynsey Road, Colombo 00800, Sri Lanka
6. Institute of Immunity and Transplantation, Royal Free Hospital and University College London, Pond Street, Hampstead, London, NW3 2QG, UK