1. Department of Pediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
2. Tygerberg Hospital, Cape Town, South Africa
3. MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
4. Haematology-Oncology Service, Department of Pediatrics and Child Health, Red Cross Children's Hospital, University of Cape Town, Cape Town, South Africa
5. Department of Pediatrics, University of the Free State, Bloemfontein, South Africa
6. Universitas Hospital, Bloemfontein, South Africa
7. Department of Pediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa
8. Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa
9. Division of Pediatric Hematology Oncology, Department of Pediatrics and Child Health, Faculty of Health Sciences, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
10. Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa
11. Department Radiation Oncology, Groote Schuur Hospital, Cape Town, South Africa
12. Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
13. Department of Ophthalmology, Groote Schuur Hospital, Cape Town, South Africa