Funding for this research was provided by:
Wellcome Trust (203077_Z_16_Z)
National Institute for Health Research (16/136/33)
Received: 18 November 2020
Accepted: 8 February 2021
First Online: 18 February 2021
Ethics approval and consent to participate
: Ethical approval was provided by the Kenya Medical Research Institute Scientific and Ethics Review Unit and written informed consent obtained from parents or guardians of all study participnats (SSC Nos. 3296, 2617 and 3149).
: Not applicable.
: The authors declare that they have no competing interests.