High Adherence Is Necessary to Realize Health Gains from Water Quality Interventions

• Type of Material: Article
• Authors: Joe Brown, London School of Hygiene and Tropical Medicine; Thomas Clasen, Emory University
• Language: English
• Date: 2012-05-07
• Publisher: Public Library of Science
• Publication Version: Final Published Version
• Copyright Statement: © 2012 Brown, Clasen. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036735
• Title of Journal or Parent Work: PLoS ONE
• ISSN: 1932-6203
• Volume: 7
• Issue: 5
• Start Page: 1
• End Page: 9
• Grant/Funding Information: This study was supported in part by a grant to the London School of Hygiene & Tropical Medicine by Unilever, Ltd.
• Research Categories: Health Sciences, Public Health

Abstract

Background Safe drinking water is critical for health. Household water treatment (HWT) has been recommended for improving access to potable water where existing sources are unsafe. Reports of low adherence to HWT may limit the usefulness of this approach, however. Methods and Findings We constructed a quantitative microbial risk model to predict gains in health attributable to water quality interventions based on a range of assumptions about pre-treatment water quality; treatment effectiveness in reducing bacteria, viruses, and protozoan parasites; adherence to treatment interventions; volume of water consumed per person per day; and other variables. According to mean estimates, greater than 500 DALYs may be averted per 100,000 person-years with increased access to safe water, assuming moderately poor pre-treatment water quality that is a source of risk and high treatment adherence (>90% of water consumed is treated). A decline in adherence from 100% to 90% reduces predicted health gains by up to 96%, with sharpest declines when pre-treatment water quality is of higher risk. Conclusions Results suggest that high adherence is essential in order to realize potential health gains from HWT.