Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.

BACKGROUND: Current guidelines recommend the use of Escherichia coli (EC) or thermotolerant ("fecal") coliforms (FC) as indicators of fecal contamination in drinking water. Despite their broad use as measures of water quality, there remains limited evidence for an association between EC or...

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Main Authors: Joshua S Gruber, Ayse Ercumen, John M Colford
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2014-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4175079?pdf=render
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author Joshua S Gruber
Ayse Ercumen
John M Colford
author_facet Joshua S Gruber
Ayse Ercumen
John M Colford
author_sort Joshua S Gruber
collection DOAJ
description BACKGROUND: Current guidelines recommend the use of Escherichia coli (EC) or thermotolerant ("fecal") coliforms (FC) as indicators of fecal contamination in drinking water. Despite their broad use as measures of water quality, there remains limited evidence for an association between EC or FC and diarrheal illness: a previous review found no evidence for a link between diarrhea and these indicators in household drinking water. OBJECTIVES: We conducted a systematic review and meta-analysis to update the results of the previous review with newly available evidence, to explore differences between EC and FC indicators, and to assess the quality of available evidence. METHODS: We searched major databases using broad terms for household water quality and diarrhea. We extracted study characteristics and relative risks (RR) from relevant studies. We pooled RRs using random effects models with inverse variance weighting, and used standard methods to evaluate heterogeneity and publication bias. RESULTS: We identified 20 relevant studies; 14 studies provided extractable results for meta-analysis. When combining all studies, we found no association between EC or FC and diarrhea (RR 1.26 [95% CI: 0.98, 1.63]). When analyzing EC and FC separately, we found evidence for an association between diarrhea and EC (RR: 1.54 [95% CI: 1.37, 1.74]) but not FC (RR: 1.07 [95% CI: 0.79, 1.45]). Across all studies, we identified several elements of study design and reporting (e.g., timing of outcome and exposure measurement, accounting for correlated outcomes) that could be improved upon in future studies that evaluate the association between drinking water contamination and health. CONCLUSIONS: Our findings, based on a review of the published literature, suggest that these two coliform groups have different associations with diarrhea in household drinking water. Our results support the use of EC as a fecal indicator in household drinking water.
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spelling doaj.art-b3cc0bd0d4604479b6344c7feb71962b2022-12-21T19:45:39ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0199e10742910.1371/journal.pone.0107429Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.Joshua S GruberAyse ErcumenJohn M ColfordBACKGROUND: Current guidelines recommend the use of Escherichia coli (EC) or thermotolerant ("fecal") coliforms (FC) as indicators of fecal contamination in drinking water. Despite their broad use as measures of water quality, there remains limited evidence for an association between EC or FC and diarrheal illness: a previous review found no evidence for a link between diarrhea and these indicators in household drinking water. OBJECTIVES: We conducted a systematic review and meta-analysis to update the results of the previous review with newly available evidence, to explore differences between EC and FC indicators, and to assess the quality of available evidence. METHODS: We searched major databases using broad terms for household water quality and diarrhea. We extracted study characteristics and relative risks (RR) from relevant studies. We pooled RRs using random effects models with inverse variance weighting, and used standard methods to evaluate heterogeneity and publication bias. RESULTS: We identified 20 relevant studies; 14 studies provided extractable results for meta-analysis. When combining all studies, we found no association between EC or FC and diarrhea (RR 1.26 [95% CI: 0.98, 1.63]). When analyzing EC and FC separately, we found evidence for an association between diarrhea and EC (RR: 1.54 [95% CI: 1.37, 1.74]) but not FC (RR: 1.07 [95% CI: 0.79, 1.45]). Across all studies, we identified several elements of study design and reporting (e.g., timing of outcome and exposure measurement, accounting for correlated outcomes) that could be improved upon in future studies that evaluate the association between drinking water contamination and health. CONCLUSIONS: Our findings, based on a review of the published literature, suggest that these two coliform groups have different associations with diarrhea in household drinking water. Our results support the use of EC as a fecal indicator in household drinking water.http://europepmc.org/articles/PMC4175079?pdf=render
spellingShingle Joshua S Gruber
Ayse Ercumen
John M Colford
Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
PLoS ONE
title Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
title_full Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
title_fullStr Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
title_full_unstemmed Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
title_short Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis.
title_sort coliform bacteria as indicators of diarrheal risk in household drinking water systematic review and meta analysis
url http://europepmc.org/articles/PMC4175079?pdf=render
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AT johnmcolford coliformbacteriaasindicatorsofdiarrhealriskinhouseholddrinkingwatersystematicreviewandmetaanalysis