ACKNOWLEDGEMENTS
The authors express special gratitude to Laura Caulfield and Jessica Fanzo at Johns Hopkins Bloomberg School of Public Health and to the study participants, without whom this research would not have been possible. This work was supported, in whole or in part, by the Bill & Melinda Gates Foundation, Grant Number OPP1163259. Under the grant conditions of the Foundation, a Creative Commons Attribution 4.0 Generic License has already been assigned to the Author Accepted Manuscript version that might arise from this submission. The design of the study was undertaken by the Johns Hopkins University and icddr,b investigative teams. The funder did not have any roles in the design, implementation, or analysis of this study.