1. Department of Medicine, Division of Dermatology, Groote Schuur Hospital and Faculty of Health Sciences University of Cape Town; Cape Town South Africa
2. SAMRC/UCT Receptor Biology Research Unit, Division of Medical Biochemistry and Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town; Cape Town South Africa
3. Department of Paediatrics, Red Cross Hospital and Faculty of Health Sciences, University of Cape Town; Cape Town South Africa
4. Department of Medicine, Faculty of Health Sciences, University of Cape Town; Cape Town South Africa