Funding for this research was provided by:
David and Lucile Packard Foundation (64569)
Received: 15 May 2017
Accepted: 26 April 2018
First Online: 11 May 2018
Ethics approval and consent to participate
: The study protocol was approved by the World Health Organization ‘Research Ethics Review Committee (WHO-ERC)’ and the ‘Research Project Review Panel (RP2)’, Project ID: A65911. All enumerators will be trained to ensure that they took appropriate measures in order protect the confidentiality of participants to the fullest extent possible. All study participants will provide written voluntary informed consent.
: All authors have agreed and have given consent for submission for publication.
: The authors declare that they have no competing interests.
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