Funding for this research was provided by:
Medical Research Council (MCA760-5QX00)
Received: 18 July 2018
Accepted: 21 September 2018
First Online: 1 November 2018
Ethics approval and consent to participate
: The study was approved by the MRC Scientific Coordinating Committee, and the joint Gambian Government/MRC Ethics Committees (SCC1253v2) and participant parents provided signed consent following a verbal and written description of the study aims.
: Not applicable.
: The authors declare that they have no competing interests.
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