Hugo C Turner1, James E Truscott2, Roy M Anderson2. 1. London Centre for Neglected Tropical Disease Research, London, UK; Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, London, W2 1PG, UK. Electronic address: hugo.turner06@imperial.ac.uk. 2. London Centre for Neglected Tropical Disease Research, London, UK; Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, London, W2 1PG, UK.