Received: 10 June 2019
Accepted: 27 January 2020
First Online: 10 February 2020
Ethical approval and consent to participate
: Ethical approvals for the study were granted by the Public Health Foundation of India Institutional Ethics Committee, Health Ministry Screening Committee (Indian Council for Medical Research), as well as from the King’s College London Research Ethics Committee (PNM- 1314-4) and the WHO’s Research Ethics Review Committee. All the participants provided informed consent for this study.
: Not applicable.
: The authors declare that they have no competing interests.