Received: 5 March 2020
Accepted: 22 December 2020
First Online: 11 January 2021
: Ethics approval for this study was provided by the Emory University Institutional Review Board (00062989) and University of the Witwatersrand Human Research Ethics Committee (M181186). Consent to participate in research was obtained at each study visit. Written consent by the Bt20+ participant or written consent by the caregiver and verbal assent by the Bt20+ participant were obtained as age appropriate.
: The authors declare that they have no competing interests.