1Vaccines and Immunity Theme, Medical Research Council Unit, Fajara, The Gambia
2Clinical Services Department, Medical Research Council Unit, Fajara, The Gambia
3Microbiology and Infection Unit, Warwick Medical School, University of Warwick, Coventry, United Kingdom
4Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
5Disease Control and Elimination Theme, Medical Research Council Unit The Gambia, Fajara, The Gambia
6Institute of Tropical Medicine, Antwerp, Belgium
7Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
8Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
9College of Medicine University of Lagos, Lagos, Nigeria
© The Author(s) 2018
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