1. McGill University; Department of Epidemiology, Biostatistics and Occupational Health; Montreal Canada
2. McGill University Health Centre - Research Institute; Division of Clinical Epidemiology; Montreal QC Canada
3. University of Cape Town; 3 Centre for Lung Infection and Immunity Unit, Department of Medicine and UCT Lung Institute; Cape Town South Africa
4. FIND; Geneva Switzerland
5. Department of Clinical Sciences, Liverpool School of Tropical Medicine; Honorary Research Fellow; Pembroke Place Liverpool UK