The University of Sydney, affiliation not provided to SSRN, affiliation not provided to SSRN, University College London, - Health Systems and Population Studies Division, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, International Centre for Diarrheal Disease Research (icddr,b), affiliation not provided to SSRN, Department of Mechanical Engineering, Bangladesh University of Engineering and Technology - Bangladesh University of Engineering and Technology and University of California, Berkeley

International Centre for Diarrheal Disease Research (icddr,b), International Centre for Diarrheal Disease Research (icddr,b), affiliation not provided to SSRN, International Centre for Diarrheal Disease Research (icddr,b), Emory University - Rollins School of Public Health, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, International Centre for Diarrheal Disease Research (ICDDR’B), - Health Systems and Population Studies Division, affiliation not provided to SSRN, affiliation not provided to SSRN, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), affiliation not provided to SSRN, Emory University, Emory University, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Bangladesh Ministry of Health and Family Welfare, Disease Control and Research - Institute of Epidemiology, Disease Control and Research - Institute of Epidemiology, affiliation not provided to SSRN, Emory University and - Health Systems and Population Studies Division