1. Department of Medical Microbiology, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia.
2. Institute of Virology, University of Bonn Medical Centre, Bonn, Germany.
3. CEA, Division of Immuno-Virology, iMETI, Fontenay-aux-Roses, France and University Paris-Sud XI, Orsay, France.
4. Tropical Infectious Diseases Research and Education Centre, University Malaya, Kuala Lumpur, Malaysia.