Funding for this research was provided by:
Bill and Melinda Gates Foundation (OPP1165083)
Received: 17 June 2018
Accepted: 5 July 2018
First Online: 20 July 2018
Consent for publication
: Not applicable
: Venkata Raghava Mohan is an Associate Editor for BMC Public Health. The other authors declare that they have no competing interests.
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