[1] Med Res Council, ZA-7505 Tygerberg, South Africa
[2] Univ Witwatersrand, Parasitol Res Programme, ZA-2050 Johannesburg, South Africa
[3] Univ Stellenbosch, Dept Haematol Pathol, ZA-7505 Stellenbosch, South Africa
[4] Tygerberg Hosp, ZA-7505 Tygerberg, South Africa