Assessing the consistency and microbiological effectiveness of household water treatment practices by urban and rural populations claiming to treat their water at home: a case study in Peru.

Ghislaine Rosa,Thomas Clasen,Maria L Huaylinos,Claudio Lanata,Ana Gil,A Mark Ibekwe

doi:10.1371/journal.pone.0114997

Abstract

BackgroundHousehold water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it. These estimates, however, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice—key factors for reducing pathogen exposure and achieving health benefits. The objective of this study was to examine how HWT practices are actually performed by households identified as HWT users, according to international monitoring standards.Methods and FindingsWe conducted a 6-month case study in urban (n = 117 households) and rural (n = 115 households) Peru, a country in which 82.8% of households report treating their water at home. We used direct observation, in-depth interviews, surveys, spot-checks, and water sampling to assess water treatment practices among households that claimed to treat their drinking water at home. While consistency of reported practices was high in both urban (94.8%) and rural (85.3%) settings, availability of treated water (based on self-report) at time of collection was low, with 67.1% and 23.0% of urban and rural households having treated water at all three sampling visits. Self-reported consumption of untreated water in the home among adults and children <5 was common and this was corroborated during home observations. Drinking water of self-reported users was significantly better than source water in the urban setting and negligible but significantly better in the rural setting. However, only 46.3% and 31.6% of households had drinking water <1 CFU/100 mL at all follow-up visits.ConclusionsOur results raise questions about the usefulness of current international monitoring of HWT practices and their usefulness as a proxy indicator for drinking water quality. The lack of consistency and sub-optimal microbiological effectiveness also raises questions about the potential of HWT to prevent waterborne diseases.

Highlights

Unsafe drinking water is a major cause of diarrheal death and disease, especially for young children and vulnerable populations in low-income countries
Systematic reviews of water quality interventions suggest that Household water treatment (HWT) is effective at improving drinkingwater quality and in preventing diarrhoea [2,3,4]
There is evidence that the health impact from HWT may be exaggerated due to reporting bias, the WHO and UNICEF have recommended the use of HWT for populations relying on unsafe supplies as part of a comprehensive strategy to prevent diarrhoea [5]

Summary

Introduction

Unsafe drinking water is a major cause of diarrheal death and disease, especially for young children and vulnerable populations in low-income countries. There is evidence that the health impact from HWT may be exaggerated due to reporting bias, the WHO and UNICEF have recommended the use of HWT for populations relying on unsafe supplies as part of a comprehensive strategy to prevent diarrhoea [5]. The results from 67 low- and middle-income countries suggest that more than 1.1 billion people report treating their water prior to drinking [8]; additional data from China brings the overall figure to at least 1.8 billion [9]. Household water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it These estimates, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice—key factors for reducing pathogen exposure and achieving health benefits. Drinking water of self-reported users was significantly better than source water in the urban setting and negligible but PLOS ONE | DOI:10.1371/journal.pone.0114997 December 18, 2014

Objectives

Methods

Results

Conclusion