The SaniPath Exposure Assessment Tool: A quantitative approach for assessing exposure to fecal contamination through multiple pathways in low resource urban settlements

• Type of Material: Article
• Authors: Suraja J. Raj, Emory University; Yuke Wang, Emory University; Habib Yakubu, Emory University; Katharine Robb, Emory University; Casey Siesel, Emory University; Jamie Green, Emory University; Amy Kirby, Emory University; Wolfgang Mairinger, Emory University; James Michiel, Emory University; Clair Null, Emory University; Eddy Perez, Emory University; Katherine Roguski, Emory University; Christine Moe, Emory University
• Language: English
• Date: 2020-06-12
• Publisher: Public Library of Science
• Publication Version: Final Published Version
• Copyright Statement: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose.
• License: Creative Commons Universal : Public Domain Dedication
• Final Published Version (URL): http://dx.doi.org/10.1371/journal.pone.0234364
• Title of Journal or Parent Work: PLoS One
• Volume: 15
• Issue: 6
• Start Page: e0234364
• End Page: e0234364
• Grant/Funding Information: The study was financially supported by the Bill & Melinda Gates Foundation, grant no. 00010161.
• Keywords: Young children; Risk; Environment; Ghana; Drinking water; Science & Technology; Accra; Science & Technology - Other Topics; Multidisciplinary Sciences; Sanitation; Neighborhoods; Escherichia coli
• Research Categories: Health Sciences, Public Health; Health Sciences, Hygiene; Sociology, Public and Social Welfare

Abstract

Inadequate sanitation can lead to exposure to fecal contamination through multiple environmental pathways and can result in adverse health outcomes. By understanding the relative importance of multiple exposure pathways, sanitation interventions can be tailored to those pathways with greatest potential public health impact. The SaniPath Exposure Assessment Tool allows users to identify and quantify human exposure to fecal contamination in low-resource urban settings through a systematic yet customizable process. The Tool includes: a project management platform; mobile data collection and a data repository; protocols for primary data collection; and automated exposure assessment analysis. The data collection protocols detail the process of conducting behavioral surveys with households, school children, and community groups to quantify contact with fecal exposure pathways and of collecting and analyzing environmental samples for E. coli as an indicator of fecal contamination. Bayesian analyses are used to estimate the percentage of the population exposed and the mean dose of fecal exposure from microbiological and behavioral data. Fecal exposure from nine pathways (drinking water, bathing water, surface water, ocean water, open drains, floodwater, raw produce, street food, and public or shared toilets) can be compared through a common metric-estimated ingestion of E. coli units (MPN or CFU) per month. The Tool generates data visualizations and recommendations for interventions designed for both scientific and lay audiences. When piloted in Accra, Ghana, the results of the Tool were comparable with that of an in-depth study conducted in the same neighborhoods and highlighted consumption of raw produce as a dominant exposure pathway. The Tool has been deployed in nine cities to date, and the results are being used by local authorities to design and prioritize programming and policy. The SaniPath Tool is a novel approach to support public-health evidence-based decision-making for urban sanitation policies and investments.