Funding for this research was provided by:
Commonwealth Scholarship Commission (NGCA-2015-051)
Medical Research Council Canada
Bill and Melinda Gates Foundation (OPP 1033751)
Imperial College London
Text and Data Mining valid from 2018-09-17
Received: 16 May 2018
Accepted: 4 September 2018
First Online: 17 September 2018
Ethics approval and consent to participate
: The process of obtaining ethical approvals, informed consent, and arranging logistical procedures for the field surveys were handled in-country by the Nigeria Ministry of Health, with technical support by the WHO.
: Not applicable.
: The authors declare that they have no competing interests.
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