1. Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
2. International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa.
3. Centre for Infectious Disease Epidemiology and Research, University of Cape Town, Cape Town, South Africa.
4. Division of Medical Virology and Institute of Infectious Disease and Molecular Medicine, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
5. National Health Laboratory Service, Cape Town, South Africa.
6. Division of Medical Virology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.