Funding for this research was provided by:
National Health and Medical Research Council (1077636, 1092789)
Received: 11 July 2017
Accepted: 16 January 2018
First Online: 29 January 2018
Ethics approval and consent to participate
: Ethical approval was provided by the Human Research and Ethics Committees of Alfred Health and Melbourne Health, Australia, and from the College of Medicine, University of Malawi, and the Medical Research Advisory Committee, PNG. All study participants gave written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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