Funding for this research was provided by:
Wellcome Trust (082384/Z/07/Z)
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01-HD084233)
Received: 24 March 2017
Accepted: 2 August 2017
First Online: 17 August 2017
Ethics approval and consent to participate
: Ethical approval for the AHRI surveillance programme has been given by the University of KwaZulu-Natal’s Biomedical Research Ethics Committee (ref BF233–09) and is renewed annually. This nested study was approved as an amendment to the overall surveillance programme. Written informed consent was obtained from all participants in the study presented in this paper.
: Not applicable.
: The authors declare that they have no competing interests.
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