1. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
2. Department of Disease Control, London School of Hygiene and Tropical Medicine, London WC1E 7HT,United Kingdom
3. Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
4. Center for Global Safe Water, Sanitation, and Hygiene, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
5. Department of Population Health Sciences, School of Public Health, Georgia State University, Atlanta, Georgia 30302, United States
6. Division of Pediatric Gastroenterology, SUNY Downstate Health Sciences University, Brooklyn, New York 11203, United States
7. Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States