Funding for this research was provided by:
Department for International Development (MR/M015386/1)
Received: 10 September 2018
Accepted: 15 February 2019
First Online: 6 March 2019
Ethics approval and consent to participate
: Ethical approval has been granted by the Kenya Medical Research Institute (KEMRI) Scientific and Ethics Review Unit (SSC protocol No. 2897).
: Not applicable.
: The authors declare that they have no competing interests.
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