1. Department of Radiology, The Royal Brompton and Harefield NHS Foundation, London
2. Department of Radiology, Guy’s and St Thomas’ NHS Foundation Trust, London
3. Department of Pediatrics and Child Health, College of Health Sciences, University of Zimbabwe, Avondale
4. Biomedical Research and Training Institute, Harare, Zimbabwe
5. London School of Hygiene and Tropical Medicine, United Kingdom
6. Liverpool School of Tropical Medicine, Pembroke Place, United Kingdom
7. Division of Pulmonary and Critical Care Medicine, University of California, San Francisco