[1] Univ Witwatersrand, Fac Hlth Sci, Dept Internal Med, Johannesburg, South Africa
[2] Univ Witwatersrand, Fac Hlth Sci, Dept Internal Med, Div Infect Dis, Johannesburg, South Africa
[3] Univ Witwatersrand, Fac Hlth Sci, Sch Pathol, Dept Clin Microbiol & Infect Dis, Johannesburg, South Africa
[4] Natl Hlth Lab Serv, Johannesburg, South Africa
[5] Univ Witwatersrand, Chris Hani Baragwanath Acad Hosp, Fac Hlth Sci, Dept Internal Med,Div Cardiol, Johannesburg, South Africa