Funding for this research was provided by:
Bill and Melinda Gates Foundation
Received: 12 October 2020
Accepted: 19 July 2021
First Online: 3 September 2021
: The ethical approval was obtained from the Institutional Review Board (IRB) of Johns Hopkins School of Public Health (IRB No: 9114), USA as well as Sigma IRB, New Delhi, India- which is the local ethics committee. Written informed consents were taken from all the participants of the study.
: Not Applicable.
: The authors declare that they have no competing interests.