Funding for this research was provided by:
Seventh Framework Programme (grant agreement number 306090)
Received: 13 July 2018
Accepted: 8 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: The research proposal was approved by Liverpool School of Tropical Medicine (Research Protocol 14.007 and Research Protocol 14.044) and Kenya Medical Research Institute (KEMRI) (Non-SSC Protocol 469). In addition, approval was received from the National Council for Science and Technology (NACOSTI) (NACOSTI/15/2058/4010). Written informed consent was sought from and signed by all interviewed respondents.
: The manuscript has anonymised information to ensure confidentiality.
: The authors declare that they have no competing interests.
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