Funding for this research was provided by:
Bill and Melinda Gates Foundation (INV-010174)
Received: 16 June 2020
Accepted: 5 December 2020
First Online: 6 January 2021
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board (IRB) of the Ethiopian Public Health Institute (Ref: EPHI/6.13/607).
: Not applicable.
: The authors have declared that no competing interests exist. KS and MB are staff members of the World Health Organization. The authors alone are responsible for the views expressed in this article and they do not necessarily represent the decisions, policy or views of the World Health Organization.