1. Department of Pneumology, Central Hospital of Maputo, Maputo 1113, Mozambique
2. Faculty of Medicine, Eduardo Mondlane University Maputo, Maputo 1113, Mozambique
3. Department of Paediatry, Central Hospital of Maputo, Maputo 1113, Mozambique
4. Operative Research Unit, Doctors with Africa Cuamm, Beira 1100, Mozambique
5. Centre for Health, Performance and Wellbeing, Anglia Ruskin University, Cambridge CB1 1PT, UK
6. Department of Medicine, University of Padua, 35128 Padova, Italy