1. Stanford Prevention Research Center, Stanford University School of Medicine, 1070 Arastradero Road, Suite 100, Stanford, CA 94304-1334, USA
2. Civil & Environmental Engineering Department, Stanford University, Stanford, CA 94305-4020, USA
3. Emmett Interdisciplinary Program in Environment and Resources, Stanford University, Stanford, CA 94305-4020, USA
4. School of Public Health, Muhimbili University of Health and Allied Sciences, P.O. Box 65015, Dar es Salaam, Tanzania