Funding for this research was provided by:
United States Agency for International Development (AID-OAA-00050)
Received: 6 June 2017
Accepted: 21 November 2018
First Online: 28 January 2019
: Not applicable.
: This research was guided by the protocol, applicable laws and regulations, and the principles of research ethics as set forth in the Belmont Report. For this study, need for consent was formally waived. Every care was taken to ensure the privacy and confidentiality of study data. The Tanzanian National Institute of Medical Research (Protocol Number NIMR/HQ/R.8c/Vol.II/767) and the U.S.-based Western Internal Review Board (Protocol Number 1160194) approved the study protocol.
: Not relevant.
: The authors declare that they have no competing interests.
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