Funding for this research was provided by:
Wellcome Trust (095875/Z/11Z)
Received: 19 February 2018
Accepted: 16 May 2018
First Online: 23 May 2018
Ethics approval and consent to participate
: The ZENITH project was approved by the Medical Research Council of Zimbabwe (MRCZ), the ethics committees for the London School of Hygiene and Tropical Medicine (LSHTM), and the Biomedical Research and Training Institute (BRTI). All participants provided written informed consent and assent.
: The authors declare that they have no competing interests.
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