1. Department of Internal Medicine, University of Witwatersrand, Johannesburg, South Africa
2. Department of Clinical Microbiology, National Health Laboratory Services & University of Witwatersrand, Johannesburg, South Africa
3. Division of Cardiology, Department of Internal Medicine, University of Witwatersrand, Johannesburg, South Africa
4. Division of Infectious Diseases, Department of Internal Medicine, University of Witwatersrand, Johannesburg, South Africa