1. Department of Medicine, University of Cape Town , Cape Town , South Africa
2. Michael G. DeGroote School of Medicine, McMaster University , Hamilton, Ontario , Canada
3. School of Medicine, University of Ottawa , Ottawa, Ontario , Canada
4. Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town , Cape Town , South Africa
5. Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town , Cape Town , South Africa