1
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Molina CA, Quiroz-Moreno C, Jarrín-V P, Díaz M, Yugsi E, Pérez-Galarza J, Baldeón-Rojas L. Bacterial community assessment of drinking water and downstream distribution systems in highland localities of Ecuador. JOURNAL OF WATER AND HEALTH 2024; 22:536-549. [PMID: 38557569 DOI: 10.2166/wh.2024.290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 01/23/2024] [Indexed: 04/04/2024]
Abstract
Bacterial communities in drinking water provide a gauge to measure quality and confer insights into public health. In contrast to urban systems, water treatment in rural areas is not adequately monitored and could become a health risk. We performed 16S rRNA amplicon sequencing to analyze the microbiome present in the water treatment plants at two rural communities, one city, and the downstream water for human consumption in schools and reservoirs in the Andean highlands of Ecuador. We tested the effect of water treatment on the diversity and composition of bacterial communities. A set of physicochemical variables in the sampled water was evaluated and correlated with the structure of the observed bacterial communities. Predominant bacteria in the analyzed communities belonged to Proteobacteria and Actinobacteria. The Sphingobium genus, a chlorine resistance group, was particularly abundant. Of health concern in drinking water reservoirs were Fusobacteriaceae, Lachnospiraceae, and Ruminococcaceae; these families are associated with human and poultry fecal contamination. We propose the latter families as relevant biomarkers for establishing local standards for the monitoring of potable water systems in highlands of Ecuador. Our assessment of bacterial community composition in water systems in the Ecuadorian highlands provides a technical background to inform management decisions.
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Affiliation(s)
- C Alfonso Molina
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Cdla. Universitaria y Gaspar de Carvajal s/n., 170521 Quito, Ecuador; Instituto de Investigación en Zoonosis (CIZ), Universidad Central del Ecuador, Cdla. Universitaria y Gaspar de Carvajal s/n., 170521, Quito, Ecuador E-mail:
| | - Cristian Quiroz-Moreno
- Department of Horticulture and Crop Science, Ohio State University, 2021 Coffey Road, Columbus OH 43210
| | - Pablo Jarrín-V
- Laboratorio de Secuenciamiento de Ácidos Nucleicos, Dirección de Gestión de la Innovación, Instituto Nacional de Biodiversidad INABIO, Pje. Rumipamba N341 y Av. de los Shyris, Quito, Ecuador
| | - Magdalena Díaz
- Instituto de Investigación en Zoonosis (CIZ), Universidad Central del Ecuador, Cdla. Universitaria y Gaspar de Carvajal s/n., 170521, Quito, Ecuador; Facultad de Ingeniería Química, Universidad Central del Ecuador, Ritter s/n y Bolivia, 170521 Quito, Ecuador; Institute of Integrative Systems Biology (I2SysBio), University of Valencia and Consejo Superior de Investigaciones Científicas (CSIC), Carrer del Catedràtic Agustín Escardino Benlloch, 46980 Paterna, Valencia, Spain
| | - Elizabeth Yugsi
- Centro de Biotecnología 'Dr Daniel Alkalay Lowitt', Universidad Técnica Federico Santa María, General Bari 699, 2390136, Valparaíso, Chile
| | - Jorge Pérez-Galarza
- Facultad de Ciencias Médicas, Universidad Central del Ecuador, Iquique N14-121 y Sodiro, Quito, Ecuador; Instituto de Investigación en Biomedicina, Universidad Central del Ecuador, Capitán Giovanni Calles y Derby, Quito, Ecuador
| | - Lucy Baldeón-Rojas
- Facultad de Ciencias Médicas, Universidad Central del Ecuador, Iquique N14-121 y Sodiro, Quito, Ecuador; Instituto de Investigación en Biomedicina, Universidad Central del Ecuador, Capitán Giovanni Calles y Derby, Quito, Ecuador
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2
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Harris AR, Daly SW, Pickering AJ, Mrisho M, Harris M, Davis J. Safe Today, Unsafe Tomorrow: Tanzanian Households Experience Variability in Drinking Water Quality. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17481-17489. [PMID: 37922469 DOI: 10.1021/acs.est.3c05275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Measuring Escherichia coli in a single-grab sample of stored drinking water is often used to characterize drinking water quality. However, if water quality exhibits variability temporally, then one-time measurement schemes may be insufficient to adequately characterize the quality of water that people consume. This study uses longitudinal data collected from 193 households in peri-urban Tanzania to assess variability in stored water quality and to characterize uncertainty with different data collection schemes. Households were visited 5 times over the course of a year. At each visit, information was collected on water management practices, and a sample of stored drinking water was collected for E. coli enumeration. Water quality was poor for households, with 80% having highly contaminated (>100 CFU per 100 mL) water during at least one visit. There was substantial variability of water quality for households, with only 3% of households having the same category (low, medium, or high) of water quality for all five visits. These data suggest a single sample would inaccurately characterize a household's drinking water quality over the course of a year and lead to misestimates of population level access to safe drinking water.
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Affiliation(s)
- Angela R Harris
- Civil, Construction, and Environmental Engineering, North Carolina State University, 915 Partners Way, Campus Box 7908, Raleigh, North Carolina 27606, United States
| | - Sean W Daly
- Civil, Construction, and Environmental Engineering, North Carolina State University, 915 Partners Way, Campus Box 7908, Raleigh, North Carolina 27606, United States
| | - Amy J Pickering
- Civil and Environmental Engineering, University California Berkeley, Berkeley, California 94720, United States
| | | | - Michael Harris
- Civil and Environmental Engineering, University California Berkeley, Berkeley, California 94720, United States
| | - Jennifer Davis
- Environmental Engineering & Science, Department of Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
- Woods Institute for the Environment, Stanford University, Stanford, California 94305, United States
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3
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Reynaert E, Steiner P, Yu Q, D'Olif L, Joller N, Schneider MY, Morgenroth E. Predicting microbial water quality in on-site water reuse systems with online sensors. WATER RESEARCH 2023; 240:120075. [PMID: 37263119 DOI: 10.1016/j.watres.2023.120075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 03/24/2023] [Accepted: 05/11/2023] [Indexed: 06/03/2023]
Abstract
Widespread implementation of on-site water reuse is hindered by the limited availability of monitoring approaches that ensure microbial quality during operation. In this study, we developed a methodology for monitoring microbial water quality in on-site water reuse systems using inexpensive and commercially available online sensors. An extensive dataset containing sensor and microbial water quality data for six of the most critical types of disruptions in membrane bioreactors with chlorination was collected. We then tested the ability of three typological machine learning algorithms - logistic regression, support-vector machine, and random forest - to predict the microbial water quality as "safe" or "unsafe" for reuse. The main criteria for model optimization was to ensure a low false positive rate (FPR) - the percentage of safe predictions when the actual condition is unsafe - which is essential to protect users health. This resulted in enforcing a fixed FPR ≤ 2%. Maximizing the true positive rate (TPR) - the percentage of safe predictions when the actual condition is safe - was given second priority. Our results show that logistic-regression-based models using only two out of the six sensors (free chlorine and oxidation-reduction potential) achieved the highest TPR. Including sensor slopes as engineered features allowed to reach similar TPRs using only one sensor instead of two. Analysis of the occurrence of false predictions showed that these were mostly early alarms, a characteristic that could be regarded as an asset in alarm management. In conclusion, the simplest algorithm in combination with only one or two sensors performed best at predicting the microbial water quality. This result provides useful insights for water quality modeling or for applications where small datasets are a common challenge and a general advantage might be gained by using simpler models that reduce the risk of overfitting, allow better interpretability, and require less computational power.
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Affiliation(s)
- Eva Reynaert
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland.
| | - Philipp Steiner
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Qixing Yu
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; Ecole Polytechnique Fédérale de Lausanne (EPFL), Section of Environmental Sciences and Engineering, 1015 Lausanne, Switzerland
| | - Lukas D'Olif
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
| | - Noah Joller
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
| | - Mariane Y Schneider
- The University of Tokyo, Next Generation Artificial Intelligence Research Center & School of Information Science and Technology, 113-8656 Tokyo, Japan.
| | - Eberhard Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
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4
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Zulu N, Idris AO, Orimolade BO, Nkambule TTI, Mamba BB, Feleni U. Approaches for the Detection of
Escherichia coli
in Wastewater: A Short Review. ChemistrySelect 2023. [DOI: 10.1002/slct.202200598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Affiliation(s)
- Nokwanda Zulu
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
| | - Azeez O. Idris
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
| | - Benjamin O. Orimolade
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
| | - Thabo T. I. Nkambule
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
| | - Bhekie B. Mamba
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
| | - Usisipho Feleni
- Institute for Nanotechnology and Water Sustainability (iNanoWS), College of Science, Engineering and Technology University of South Africa, Florida Campus 1710 Johannesburg South Africa
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Nguyen KH, Smith S, Roundtree A, Feistel DJ, Kirby AE, Levy K, Mattioli MC. Fecal indicators and antibiotic resistance genes exhibit diurnal trends in the Chattahoochee River: Implications for water quality monitoring. Front Microbiol 2022; 13:1029176. [PMID: 36439800 PMCID: PMC9684717 DOI: 10.3389/fmicb.2022.1029176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/19/2022] [Indexed: 11/12/2022] Open
Abstract
Water bodies that serve as sources of drinking or recreational water are routinely monitored for fecal indicator bacteria (FIB) by state and local agencies. Exceedances of monitoring thresholds set by those agencies signal likely elevated human health risk from exposure, but FIB give little information about the potential source of contamination. To improve our understanding of how within-day variation could impact monitoring data interpretation, we conducted a study at two sites along the Chattahoochee River that varied in their recreational usage and adjacent land-use (natural versus urban), collecting samples every 30 min over one 24-h period. We assayed for three types of microbial indicators: FIB (total coliforms and Escherichia coli); human fecal-associated microbial source tracking (MST) markers (crAssphage and HF183/BacR287); and a suite of clinically relevant antibiotic resistance genes (ARGs; blaCTX-M, blaCMY, MCR, KPC, VIM, NDM) and a gene associated with antibiotic resistance (intl1). Mean levels of FIB and clinically relevant ARGs (blaCMY and KPC) were similar across sites, while MST markers and intI1 occurred at higher mean levels at the natural site. The human-associated MST markers positively correlated with antibiotic resistant-associated genes at both sites, but no consistent associations were detected between culturable FIB and any molecular markers. For all microbial indicators, generalized additive mixed models were used to examine diurnal variability and whether this variability was associated with environmental factors (water temperature, turbidity, pH, and sunlight). We found that FIB peaked during morning and early afternoon hours and were not associated with environmental factors. With the exception of HF183/BacR287 at the urban site, molecular MST markers and intI1 exhibited diurnal variability, and water temperature, pH, and turbidity were significantly associated with this variability. For blaCMY and KPC, diurnal variability was present but was not correlated with environmental factors. These results suggest that differences in land use (natural or urban) both adjacent and upstream may impact overall levels of microbial contamination. Monitoring agencies should consider matching sample collection times with peak levels of target microbial indicators, which would be in the morning or early afternoon for the fecal associated indicators. Measuring multiple microbial indicators can lead to clearer interpretations of human health risk associated with exposure to contaminated water.
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Affiliation(s)
| | - Shanon Smith
- Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Alexis Roundtree
- Waterborne Disease Prevention Branch, Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Dorian J. Feistel
- Waterborne Disease Prevention Branch, Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Amy E. Kirby
- Waterborne Disease Prevention Branch, Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Karen Levy
- Rollins School of Public Health, Emory University, Atlanta, GA, United States
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, United States
| | - Mia Catharine Mattioli
- Rollins School of Public Health, Emory University, Atlanta, GA, United States
- Waterborne Disease Prevention Branch, Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
- *Correspondence: Mia Catharine Mattioli,
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6
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Drinking Water Quality and Public Health in the Kathmandu Valley, Nepal: Coliform Bacteria, Chemical Contaminants, and Health Status of Consumers. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2022; 2022:3895859. [PMID: 35190745 PMCID: PMC8858048 DOI: 10.1155/2022/3895859] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 01/21/2022] [Indexed: 12/17/2022]
Abstract
Residents of Nepal’s Kathmandu Valley draw drinking water from tube wells, dug wells, and stone spouts, all of which have been reported to have serious water quality issues. In this study, we analyzed drinking water samples from 35 tube wells, dug wells, stone spouts, and municipal tap water for bacterial and chemical contaminants, including total and fecal coliform, aluminum, arsenic, barium, beryllium, boron, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. We also asked a sampling of households who used these specific water sources to rate the taste of their water, list any waterborne diseases they were aware of, and share basic health information about household members. This survey provided us with information from 146 households and 603 individuals. We found widespread bacterial contamination of water sources, with 94% of sources having detectable total or fecal coliform. Nepal Drinking Water Quality Standards and World Health Organization (WHO) Drinking-Water Guidelines or health-based values were exceeded for aluminum (max = 0.53 mg/L), arsenic (max = 0.071 mg/L), iron (max = 7.22 mg/L), and manganese (max = 3.229 mg/L). The distribution of water sources with high arsenic, iron, and manganese appeared to be associated with floodplain deposits. Mixed effects logistic regression models were used to examine the interactions between social factors and water contaminants and their effects on household members’ health. Consumers of water sources with both high and low concentrations of manganese were less likely to have a positive attitude towards school than those whose water sources had moderate concentrations of manganese. Social factors, especially education, played a large role in predicting individual health outcomes. Household taste ratings of drinking water were not correlated with iron or manganese concentrations, suggesting that WHO’s reliance on aesthetic criteria for these contaminants instead of formal drinking-water guidelines may not be sufficient to protect public health.
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7
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Vinueza D, Ochoa-Herrera V, Maurice L, Tamayo E, Mejía L, Tejera E, Machado A. Determining the microbial and chemical contamination in Ecuador's main rivers. Sci Rep 2021; 11:17640. [PMID: 34480050 PMCID: PMC8531378 DOI: 10.1038/s41598-021-96926-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 08/18/2021] [Indexed: 02/07/2023] Open
Abstract
One major health issue is the microbial and chemical contamination of natural freshwater, particularly in Latin American countries, such as Ecuador, where it is still lacking wastewater treatment plants. This study analyzed the water quality in twelve rivers of Ecuador (Coastal, Andean, and Amazonian regions). All rivers showed levels of E. coli and total coliforms above the maximum limit according to International and Ecuadorian legislations. The most polluted rivers were Zamora, Esmeraldas and Machángara. Also, E. coli pathotypes were found in six rivers. Several physicochemical and metal parameters were detected in high levels, such as CODTOTAL (in eight rivers), TSS (in six rivers), TS (in two rivers), Al (in nine rivers), Zn (in eight rivers), Pb (in three rivers), Cu (in three rivers), Fe (in two rivers), and Mn (in Machángara River). Our results agree with other studies in Latin America (such as Colombia, Brazil, and Peru) reporting similar contamination in water resources used for agriculture, livestock, and human consumption. Overall, Guayas, Guayllabamba, and Machángara Rivers showed the highest levels of physicochemical parameters (such as CODTOTAL and TSS) and metal concentrations (such as copper, zinc, aluminum, iron, and manganese). Further studies should evaluate contamination sources and public health impact.
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Affiliation(s)
- Dayana Vinueza
- grid.412251.10000 0000 9008 4711Instituto de Microbiología, Colegio de Ciencias Biológicas y Ambientales (COCIBA), Universidad San Francisco de Quito (USFQ), Diego de Robles y Vía Interoceánica, Campus Cumbayá, Casilla Postal 17-1200-841, Quito, 170901 Ecuador
| | - Valeria Ochoa-Herrera
- grid.412251.10000 0000 9008 4711Colegio de Ciencias e Ingeniería, Instituto Biósfera, Universidad San Francisco de Quito (USFQ), El Politécnico, Quito, 170901 Ecuador ,grid.10698.360000000122483208Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 USA
| | - Laurence Maurice
- grid.462928.30000 0000 9033 1612Geosciences Environnement Toulouse, CNRS/IRD/CNES/Université Paul Sabatier, 14 avenue Edouard Belin, 31400 Toulouse, France ,grid.442269.f0000 0001 0299 0990Área de Salud de la Universidad Andina Simón Bolívar, Área de Salud, Toledo N22-80, P.O. Box 17-12-569, Quito, 170143 Ecuador
| | - Esteban Tamayo
- grid.412251.10000 0000 9008 4711Colegio de Ciencias e Ingeniería, Instituto Biósfera, Universidad San Francisco de Quito (USFQ), El Politécnico, Quito, 170901 Ecuador
| | - Lorena Mejía
- grid.412251.10000 0000 9008 4711Instituto de Microbiología, Colegio de Ciencias Biológicas y Ambientales (COCIBA), Universidad San Francisco de Quito (USFQ), Diego de Robles y Vía Interoceánica, Campus Cumbayá, Casilla Postal 17-1200-841, Quito, 170901 Ecuador
| | - Eduardo Tejera
- grid.442184.f0000 0004 0424 2170Facultad de Ingeniería y Ciencias Agropecuarias Aplicadas, Grupo de Bioquimioinformática, Universidad de Las Américas, Quito, 170125 Ecuador
| | - António Machado
- grid.412251.10000 0000 9008 4711Instituto de Microbiología, Colegio de Ciencias Biológicas y Ambientales (COCIBA), Universidad San Francisco de Quito (USFQ), Diego de Robles y Vía Interoceánica, Campus Cumbayá, Casilla Postal 17-1200-841, Quito, 170901 Ecuador
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8
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Comparison of the ColiPlate™ Kit with Two Common E. coli Enumeration Methods for Water. WATER 2021. [DOI: 10.3390/w13131804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Quantitatively assessing fecal indicator bacteria in drinking water from limited resource settings (e.g., disasters, remote areas) can inform public health strategies for reducing waterborne illnesses. This study aimed to compare two common approaches for quantifying Escherichia coli (E. coli) density in natural water versus the ColiPlate™ kit approach. For comparing methods, 41 field samples from natural water sources in Kentucky (USA) were collected. E. coli densities were then determined by (1) membrane filtration in conjunction with modified membrane-thermotolerant E. coli (mTEC) agar, (2) Idexx Quanti-Tray® 2000 with the Colilert® substrate, and (3) the Bluewater Biosciences ColiPlate kit. Significant correlations were observed between E. coli density data for all three methods (p < 0.001). Paired t-test results showed no difference in E. coli densities determined by all the methods (p > 0.05). Upon assigning modified mTEC as the reference method for determining the World Health Organization-assigned “very high-risk” levels of fecal contamination (>100 E. coli CFU/100 mL), both ColiPlate and Colilert exhibited excellent discrimination for screening very high-risk levels according to the area under the receiver operating characteristic curve (~89%). These data suggest ColiPlate continues to be an effective monitoring tool for quantifying E. coli density and characterizing fecal contamination risks from water.
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9
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Goddard FB, Ban R, Barr DB, Brown J, Cannon J, Colford JM, Eisenberg JNS, Ercumen A, Petach H, Freeman MC, Levy K, Luby SP, Moe C, Pickering AJ, Sarnat JA, Stewart J, Thomas E, Taniuchi M, Clasen T. Measuring Environmental Exposure to Enteric Pathogens in Low-Income Settings: Review and Recommendations of an Interdisciplinary Working Group. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11673-11691. [PMID: 32813503 PMCID: PMC7547864 DOI: 10.1021/acs.est.0c02421] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 05/06/2023]
Abstract
Infections with enteric pathogens impose a heavy disease burden, especially among young children in low-income countries. Recent findings from randomized controlled trials of water, sanitation, and hygiene interventions have raised questions about current methods for assessing environmental exposure to enteric pathogens. Approaches for estimating sources and doses of exposure suffer from a number of shortcomings, including reliance on imperfect indicators of fecal contamination instead of actual pathogens and estimating exposure indirectly from imprecise measurements of pathogens in the environment and human interaction therewith. These shortcomings limit the potential for effective surveillance of exposures, identification of important sources and modes of transmission, and evaluation of the effectiveness of interventions. In this review, we summarize current and emerging approaches used to characterize enteric pathogen hazards in different environmental media as well as human interaction with those media (external measures of exposure), and review methods that measure human infection with enteric pathogens as a proxy for past exposure (internal measures of exposure). We draw from lessons learned in other areas of environmental health to highlight how external and internal measures of exposure can be used to more comprehensively assess exposure. We conclude by recommending strategies for advancing enteric pathogen exposure assessments.
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Affiliation(s)
- Frederick
G. B. Goddard
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Radu Ban
- Bill and
Melinda Gates Foundation, Seattle, Washington 98109, United States
| | - Dana Boyd Barr
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Joe Brown
- School of
Civil and Environmental Engineering, Georgia
Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jennifer Cannon
- Centers
for Disease Control and Prevention Foundation, Atlanta, Georgia 30308, United States
| | - John M. Colford
- Division
of Epidemiology and Biostatistics, School of Public Health, University of California−Berkeley, Berkeley, California 94720, United States
| | - Joseph N. S. Eisenberg
- Department
of Epidemiology, University of Michigan
School of Public Health, Ann Arbor, Michigan 48109, United States
| | - Ayse Ercumen
- Department
of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Helen Petach
- U.S. Agency
for International Development, Washington, DC 20004, United States
| | - Matthew C. Freeman
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Karen Levy
- Department
of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington 98105, United States
| | - Stephen P. Luby
- Division
of Infectious Diseases and Geographic Medicine, Stanford University, California 94305, United States
| | - Christine Moe
- Center
for
Global Safe Water, Sanitation and Hygiene, Rollins School of Public
Health, Emory University, Atlanta, Georgia 30322, United States
| | - Amy J. Pickering
- Department
of Civil and Environmental Engineering, School of Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Jeremy A. Sarnat
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Jill Stewart
- Department
of Environmental Sciences and Engineering, Gillings School of Global
Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Evan Thomas
- Mortenson
Center in Global Engineering, University
of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Mami Taniuchi
- Division
of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Thomas Clasen
- Gangarosa
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
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10
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Holcomb DA, Knee J, Sumner T, Adriano Z, de Bruijn E, Nalá R, Cumming O, Brown J, Stewart JR. Human fecal contamination of water, soil, and surfaces in households sharing poor-quality sanitation facilities in Maputo, Mozambique. Int J Hyg Environ Health 2020; 226:113496. [PMID: 32135507 PMCID: PMC7174141 DOI: 10.1016/j.ijheh.2020.113496] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/09/2020] [Accepted: 02/20/2020] [Indexed: 12/12/2022]
Abstract
Identifying the origin of fecal contamination can support more effective interventions to interrupt enteric pathogen transmission. Microbial source tracking (MST) assays may help to identify environmental routes of pathogen transmission although these assays have performed poorly in highly contaminated domestic settings, highlighting the importance of both diagnostic validation and understanding the context-specific ecological, physical, and sociodemographic factors driving the spread of fecal contamination. We assessed fecal contamination of compounds (clusters of 2-10 households that share sanitation facilities) in low-income neighborhoods of urban Maputo, Mozambique, using a set of MST assays that were validated with animal stool and latrine sludge from study compounds. We sampled five environmental compartments involved in fecal microbe transmission and exposure: compound water source, household stored water and food preparation surfaces, and soil from the entrance to the compound latrine and the entrances to each household. Each sample was analyzed by culture for the general fecal indicator Escherichia coli (cEC) and by real-time PCR for the E. coli molecular marker EC23S857, human-associated markers HF183/BacR287 and Mnif, and GFD, an avian-associated marker. We collected 366 samples from 94 households in 58 compounds. At least one microbial target (indicator organism or marker gene) was detected in 96% of samples (353/366), with both E. coli targets present in the majority of samples (78%). Human targets were frequently detected in soils (59%) and occasionally in stored water (17%) but seldom in source water or on food surfaces. The avian target GFD was rarely detected in any sample type but was most common in soils (4%). To identify risk factors of fecal contamination, we estimated associations with sociodemographic, meteorological, and physical sample characteristics for each microbial target and sample type combination using Bayesian censored regression for target concentration responses and Bayesian logistic regression for target detection status. Associations with risk factors were generally weak and often differed in direction between different targets and sample types, though relationships were somewhat more consistent for physical sample characteristics. Wet soils were associated with elevated concentrations of cEC and EC23S857 and odds of detecting HF183. Water storage container characteristics that expose the contents to potential contact with hands and other objects were weakly associated with human target detection. Our results describe a setting impacted by pervasive domestic fecal contamination, including from human sources, that was largely disconnected from the observed variation in socioeconomic and sanitary conditions. This pattern suggests that in such highly contaminated settings, transformational changes to the community environment may be required before meaningful impacts on fecal contamination can be realized.
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Affiliation(s)
- David A Holcomb
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jackie Knee
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Trent Sumner
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Zaida Adriano
- We Consult, Maputo, Mozambique; Departamento de Geografia, Universidade Eduardo Mondlane, Maputo, Mozambique
| | | | - Rassul Nalá
- Instituto Nacional de Saúde, Ministério da Saúde, Maputo, Mozambique
| | - Oliver Cumming
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Jill R Stewart
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
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11
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McGuinness SL, O'Toole J, Barker SF, Forbes AB, Boving TB, Giriyan A, Patil K, D'Souza F, Vhaval R, Cheng AC, Leder K. Household Water Storage Management, Hygiene Practices, and Associated Drinking Water Quality in Rural India. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:4963-4973. [PMID: 32167297 DOI: 10.1021/acs.est.9b04818] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Household drinking water storage is commonly practiced in rural India. Fecal contamination may be introduced at the water source, during collection, storage, or access. Within a trial of a community-level water supply intervention, we conducted five quarterly household-level surveys to collect information about water, sanitation, and hygiene practices in rural India. In a random subsample of households, we tested stored drinking water samples for Escherichia coli, concurrently observing storage and access practices. We conducted 9961 surveys and collected 3296 stored water samples. Stored water samples were frequently contaminated with E. coli (69%), and E. coli levels were the highest during the wet season. Most households contributing two or more drinking water samples had detectable E. coli in some (47%) or all (44%) samples. Predictors of stored water contamination with E. coli included consumption of river water and open defecation; consumption of reverse osmosis-treated water and safe water access practices appeared to be protective. Until households can be reached with on-premises continuous safe water supplies, suboptimal household water storage practices are likely to continue. Improvements to source water quality alone are unlikely to prevent exposure to contaminated drinking water unless attention is also given to improving household water storage, access, and sanitation practices.
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Affiliation(s)
- Sarah L McGuinness
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - Joanne O'Toole
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - S Fiona Barker
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - Andrew B Forbes
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - Thomas B Boving
- Department of Geosciences & Department of Civil and Environmental Engineering, University of Rhode Island, Kingston, Rhode Island 02281, United States
| | - Asha Giriyan
- The Energy and Resources Institute (TERI), Southern Regional Centre, Santa Cruz, Goa 403005, India
| | - Kavita Patil
- The Energy and Resources Institute (TERI), Southern Regional Centre, Santa Cruz, Goa 403005, India
| | - Fraddry D'Souza
- The Energy and Resources Institute (TERI), Southern Regional Centre, Santa Cruz, Goa 403005, India
| | - Ramkrishna Vhaval
- The Energy and Resources Institute (TERI), Southern Regional Centre, Santa Cruz, Goa 403005, India
| | - Allen C Cheng
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
| | - Karin Leder
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria 3004, Australia
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12
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Kundu A, Smith WA, Harvey D, Wuertz S. Drinking Water Safety: Role of Hand Hygiene, Sanitation Facility, and Water System in Semi-Urban Areas of India. Am J Trop Med Hyg 2019; 99:889-898. [PMID: 30062991 DOI: 10.4269/ajtmh.16-0819] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Poor drinking water quality is one of the main causes of acute diarrheal disease in developing countries. The study investigated the relationship between fecal contamination of hands, stored drinking water, and source waters in India. We further evaluated the environmental and behavioral factors associated with recontamination of water between collection and consumption. The bacterial contamination, that is, Escherichia coli (log10 most probable number per two hands), found on mothers' hands (mean = 1.11, standard deviation [SD] = 1.2, N = 152) was substantially higher than that on their children younger than 5 years (mean = 0.64, SD = 1.0, and N = 152). We found a low level of E. coli (< 1 per 100 mL) in the source water samples; however, E. coli contamination in stored drinking water was above the recommended guidelines of the World Health Organization. The study also found that E. coli on hands was significantly associated with E. coli in the stored drinking water (P < 0.001). Moreover, E. coli was positively associated with gastrointestinal symptoms (odds ratio 1.42, P < 0.05). In the households with elevated levels (> 100 E. coli/100 mL) of fecal contamination, we found that 43.5% had unimproved sanitation facilities, poor water handling practices, and higher diarrheal incidences. The water quality deterioration from the source to the point of consumption is significant. This necessitates effective interventions in collection, transport, storage, and extraction practices when hand-water contact is likely to occur. These findings support the role of hands in the contamination of stored drinking water and suggest that clean source water does not guarantee safe water at the point of consumption.
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Affiliation(s)
- Arti Kundu
- School of Veterinary Medicine, One Health Institute, University of California, Davis, California
| | - Woutrina A Smith
- School of Veterinary Medicine, One Health Institute, University of California, Davis, California
| | - Danielle Harvey
- Department of Public Health Sciences, School of Medicine, University of California, Davis, California
| | - Stefan Wuertz
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore, Singapore.,Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore.,Department of Civil and Environmental Engineering, University of California, Davis, California
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13
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Concentration Detection of the E. coli Bacteria in Drinking Water Treatment Plants through an E-Nose and a Volatiles Extraction System (VES). WATER 2019. [DOI: 10.3390/w11040774] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Water quality control remains an important topic of public health since some diseases, such as diarrhea, hepatitis, and cholera, are caused by its consumption. The microbiological quality of drinking water relies mainly on monitoring of Escherichia coli, a bacteria indicator which serves as an early sentinel of potential health hazards for the population. In this study, an electronic nose coupled to a volatile extraction system (was evaluated for the detection of the emitted compounds by E. coli in water samples where its capacity for the quantification of the bacteria was demonstrated). To achieve this purpose, the multisensory system was subjected to control samples for training. Later, it was tested with samples from drinking water treatment plants in two locations of Colombia. For the discrimination and classification of the water samples, the principal component analysis method was implemented obtaining a discrimination variance of 98.03% of the measurements to different concentrations. For the validation of the methodology, the membrane filtration technique was used. In addition, two classification methods were applied to the dataset where a success rate of 90% of classification was obtained using the discriminant function analysis and having a probabilistic neural network coupled to the cross-validation technique (leave-one-out) where a classification rate of 80% was obtained. The application of this methodology achieved an excellent classification of the samples, discriminating the free samples of E. coli from those that contained the bacteria. In the same way, it was observed that the system could correctly estimate the concentration of this bacteria in the samples. The proposed method in this study has a high potential to be applied in the determination of E. coli in drinking water since, in addition for estimating concentration ranges and having the necessary sensitivity, it significantly reduces the time of analysis compared to traditional methods.
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Thomson KK, Rahman A, Cooper TJ, Sarkar A. Exploring relevance, public perceptions, and business models for establishment of private well water quality monitoring service. Int J Health Plann Manage 2019; 34:e1098-e1118. [PMID: 30734974 DOI: 10.1002/hpm.2747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 01/14/2019] [Indexed: 11/06/2022] Open
Abstract
Existing public policies mostly focus on public water systems, leaving aside the quality issues regarding private wells in small and rural locations. Establishment of affordable and accessible water quality monitoring services may ensure acceptable levels of all the parameters. This paper aims to explore (a) health risk because of chemical contaminants of private wells, (b) population perspective on well water quality and monitoring, and (c) to create a business model of a centralized water quality monitoring service. The results show potential problems with toxic levels of arsenic, barium, cadmium, chromium, lead, mercury, and selenium. About 5% of the province's population is at risk for potential exposure to contaminated private well water. The survey reinforces that the successful implementation of water testing laboratories for private wells is a shared responsibility between well owners and the government organizations, and almost three-fourths respondents were willing to share the cost up to certain limit. A business model including financial projections for a centralized water testing laboratory is presented. Drinking of unmonitored private well water is putting population health at risk. Either strong regulation with mandatory water testing or voluntary water testing with adequate government subsidy can ensure sustainable function of a centralized water testing laboratory.
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Affiliation(s)
- Kalen K Thomson
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Arifur Rahman
- Division of Community Health and Humanities, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Tom J Cooper
- Faculty of Business Administration, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Atanu Sarkar
- Division of Community Health and Humanities, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
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15
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Marie V, Lin J. Microbial Indicators and Environmental Relationships in the Umhlangane River, Durban, South Africa. Open Life Sci 2018; 13:385-395. [PMID: 33817107 PMCID: PMC7874719 DOI: 10.1515/biol-2018-0047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 07/18/2018] [Indexed: 11/15/2022] Open
Abstract
The use of rivers for recreational and domestic practices makes it imperative to scrutinize the water quality circulating within surrounding communities. The complexity of biological, physical and chemical constituents in water is constantly evolving. This study evaluated various microbial and physico-chemical parameters in a polluted river system over a 12-month period. Apart from an increase in chemical pollutants, elevated levels of E. coli, total (TC) and faecal (FC) coliforms, and Shigella species could be attributed to faecal contamination entering the catchment. Canonical correspondence analysis revealed a strong relationship between FC, TC and temperature whereas moderate interactions was seen between total dissolved solids, electrical conductivity, TC and FC populations. Furthermore, close relationships between the bacterial and phage communities were also observed. The complex interactions of these physico-chemical and microbial indicators could be due to anthropogenic activities, changing climatic conditions and the excreta of infected and non-infected individuals entering the river. Assessing the complexity of aquatic ecosystems can aid in the development of novel, customizable, inexpensive water purification tools.
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Affiliation(s)
- Veronna Marie
- Discipline of Microbiology, School of Life Sciences, University of KwaZulu-Natal (Westville), Private Bag X54001, Durban, South Africa
| | - Johnson Lin
- School of Life Sciences, University of KwaZulu- Natal (Westville), Private Bag X54001, Durban 4000, Republic of South Africa
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16
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Feleke H, Medhin G, Kloos H, Gangathulasi J, Asrat D. Household-stored drinking water quality among households of under-five children with and without acute diarrhea in towns of Wegera District, in North Gondar, Northwest Ethiopia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:669. [PMID: 30353421 PMCID: PMC6208974 DOI: 10.1007/s10661-018-7033-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 10/08/2018] [Indexed: 05/28/2023]
Abstract
Contamination of drinking water in household water storage containers and inadequate water supplies are common public burdens in low- and middle-income countries, including towns in Wegera District, Ethiopia. Our study aimed to assess the quality of drinking water and identify factors associated with diarrhea in households with under-five (U5) children with and without diarrhea in Ambagiorgis and Gedebge towns in Wegera District. Stored drinking water samples from households with U5 children with and without diarrhea had fecal coliform (FC) counts of 59 (86.8%) and 55 (82.1%) (p > 0.05) and fecal streptococci (FS) counts of 29 (42.7%) and 24 (35.8%) (p > 0.05), respectively. The very high sanitary risk scores were 32 (47.1%) and 21 (31.3%) for FC (p > 0.05); 25 (36.8%) and 3 (4.5%) for FS (p < 0.001), respectively. Contamination of the stored drinking water samples with FS was significantly higher in households with diarrhetic U5 children in the low- and medium-risk ranges (p < 0.05). Water turbidity of 47 (69.1%) and 23 (34.3%) in households with U5 children with and without diarrhea, respectively, was above the permissible level (p < 0.001). The residual free chlorine (RFC) in all the household-stored drinking water samples was below the World Health Organization (WHO) permissible level and temperatures of all the household-stored drinking water samples were permissible. Promotion and advocacy of good stored drinking water handling practices are essential for decreasing the high risk of microbial contamination in both study areas. We recommend education interventions targeting personal hygiene and drinking water handling at the household level.
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Affiliation(s)
- Hailemariam Feleke
- Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Girmay Medhin
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Helmut Kloos
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
| | | | - Daniel Asrat
- Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
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17
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Islam M, Ercumen A, Naser AM, Unicomb L, Rahman M, Arnold BF, Colford JM, Luby SP. Effectiveness of the Hydrogen Sulfide Test as a Water Quality Indicator for Diarrhea Risk in Rural Bangladesh. Am J Trop Med Hyg 2017; 97:1867-1871. [PMID: 29141754 PMCID: PMC5805062 DOI: 10.4269/ajtmh.17-0387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Microbiological water quality is usually assessed by the identification of Escherichia coli (E. coli), a fecal indicator. The hydrogen sulfide (H2S) test is an inexpensive, easy-to-use, and portable alternative field-based water quality test. Our study evaluated the H2S test’s effectiveness as a water quality indicator for diarrhea risk. Field workers collected stored drinking water samples for H2S analysis and detection of E. coli by membrane filtration and measured caregiver-reported diarrhea among children < 5 years in the same households 1 month later. We assessed the association between the H2S test (incubated for 24 hours and 48 hours) and diarrhea prevalence, with 2-day and 7-day symptom recall periods (N = 1,348). We determined the sensitivity, specificity, and positive and negative predictive value (PPV, NPV) of the H2S test compared with E. coli (N = 525). Controlling for potentially confounding covariates, H2S-positive water (at 24 or 48 hours) was not associated with 2-day diarrhea prevalence (24-hour prevalence ratio [PR] = 1.03, 95% confidence interval [CI]: 0.63–1.69; 48-hour PR = 0.89, 95% CI: 0.58–1.38) or 7-day diarrhea prevalence (24-hour PR = 1.17, 95% CI: 0.76–1.78; 48-hour PR = 1.21, 95% CI: 0.81–1.80). The sensitivity, PPV, and NPV of the H2S test was significantly higher when the H2S test was incubated for 48 versus 24 hours whereas specificity showed the opposite trend. H2S test sensitivity, PPV, and NPV increased with increasing E. coli levels, consistent with previous evidence that the H2S test is a useful water quality tool in high-contamination settings. However, our results suggest that the H2S test is not an effective indicator for waterborne diarrhea.
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Affiliation(s)
- Mahfuza Islam
- Environmental Intervention Unit, Enteric and Respiratory Infections Program, Infectious Disease Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b)
| | - Ayse Ercumen
- Division of Epidemiology, School of Public Health, University of California, Berkeley, California
| | - Abu Mohd Naser
- Department of Environmental Health Sciences. Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Leanne Unicomb
- Environmental Intervention Unit, Enteric and Respiratory Infections Program, Infectious Disease Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b)
| | - Mahbubur Rahman
- Environmental Intervention Unit, Enteric and Respiratory Infections Program, Infectious Disease Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b)
| | - Benjamin F Arnold
- Division of Epidemiology, School of Public Health, University of California, Berkeley, California
| | - John M Colford
- Division of Epidemiology, School of Public Health, University of California, Berkeley, California
| | - Stephen P Luby
- Woods Institute for the Environment, Stanford University, Stanford, California
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18
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Reese H, Routray P, Torondel B, Sclar G, Delea MG, Sinharoy SS, Zambrano L, Caruso B, Mishra SR, Chang HH, Clasen T. Design and rationale of a matched cohort study to assess the effectiveness of a combined household-level piped water and sanitation intervention in rural Odisha, India. BMJ Open 2017; 7:e012719. [PMID: 28363920 PMCID: PMC5387990 DOI: 10.1136/bmjopen-2016-012719] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Government efforts to address massive shortfalls in rural water and sanitation in India have centred on construction of community water sources and toilets for selected households. However, deficiencies with water quality and quantity at the household level and community coverage and actual use of toilets have led Gram Vikas, a local non-governmental organization in Odisha, India, to develop an approach that provides household-level piped water connections contingent on full community-level toilet coverage. METHODS This matched cohort study was designed to assess the effectiveness of a combined piped water and sanitation intervention. Households with children <5 years in 45 randomly selected intervention villages and 45 matched control villages will be followed over 17 months. The primary outcome is prevalence of diarrhoeal diseases; secondary health outcomes include soil-transmitted helminth infection, nutritional status, seroconversion to enteric pathogens, urogenital infections and environmental enteric dysfunction. In addition, intervention effects on sanitation and water coverage, access and use, environmental fecal contamination, women's empowerment, as well as collective efficacy, and intervention cost and cost-effectiveness will be assessed. ETHICS AND DISSEMINATION The study protocol has been reviewed and approved by the ethics boards of the London School of Hygiene and Tropical Medicine, UK and KIIT University, Bhubaneswar, India. Findings will be disseminated via peer-reviewed literature and presentation to stakeholders, government officials, implementers and researchers. TRIAL REGISTRATION NUMBER NCT02441699.
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Affiliation(s)
- Heather Reese
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | | | - Belen Torondel
- London School of Hygiene and Tropical Medicine, London, UK
| | - Gloria Sclar
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Maryann G Delea
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- London School of Hygiene and Tropical Medicine, London, UK
| | - Sheela S Sinharoy
- Nutrition and Health Sciences Program, Laney Graduate School, Emory University, Atlanta, Georgia, USA
| | - Laura Zambrano
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Bethany Caruso
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Samir R Mishra
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
| | - Howard H Chang
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Thomas Clasen
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- London School of Hygiene and Tropical Medicine, London, UK
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19
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Arredondo-Hernandez LJR, Diaz-Avalos C, Lopez-Vidal Y, Castillo-Rojas G, Mazari-Hiriart M. FRNA Bacteriophages as Viral Indicators of Faecal Contamination in Mexican Tropical Aquatic Systems. PLoS One 2017; 12:e0170399. [PMID: 28114378 PMCID: PMC5256921 DOI: 10.1371/journal.pone.0170399] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 01/04/2017] [Indexed: 02/01/2023] Open
Abstract
A particular challenge to water safety in populous intertropical regions is the lack of reliable faecal indicators to detect microbiological contamination of water, while the numerical relationships of specific viral indicators remain largely unexplored. The aim of this study was to investigate the numerical relationships of FRNA-bacteriophage genotypes, adenovirus 41, and human adenoviruses (HADV) in Mexican surface water systems to assess sewage contamination. We studied the presence of HADV, HADV41 and FRNA bacteriophage genotypes in water samples and quantified by qPCR and RT-qPCR. Virus and water quality indicator variances, as analyzed by principal component analysis and partial least squared regression, followed along the major percentiles of water faecal enterococci. FRNA bacteriophages adequately deciphered viral and point source water contamination. The strongest correlation for HADV was with FRNA bacteriophage type II, in water samples higher than the 50th percentiles of faecal enterococci, thus indicating urban pollution. FRNA bacteriophage genotypes I and III virus indicator performances were assisted by their associations with electrical conductivity and faecal enterococci. In combination, our methods are useful for inferring water quality degradation caused by sewage contamination. The methods used have potential for determining source contamination in water and, specifically, the presence of enteric viruses where clean and contaminated water have mixed.
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Affiliation(s)
- Luis Jose Rene Arredondo-Hernandez
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
- * E-mail:
| | - Carlos Diaz-Avalos
- Departamento de Probabilidad y Estadística, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Yolanda Lopez-Vidal
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Gonzalo Castillo-Rojas
- Programa de Inmunología Molecular Microbiana, Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Marisa Mazari-Hiriart
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
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Mellor J, Kumpel E, Ercumen A, Zimmerman J. Systems Approach to Climate, Water, and Diarrhea in Hubli-Dharwad, India. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13042-13051. [PMID: 27783483 DOI: 10.1021/acs.est.6b02092] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Anthropogenic climate change will likely increase diarrhea rates for communities with inadequate water, sanitation, or hygiene facilities including those with intermittent water supplies. Current approaches to study these impacts typically focus on the effect of temperature on all-cause diarrhea while excluding precipitation and diarrhea etiology while not providing actionable adaptation strategies. We develop a partially mechanistic, systems approach to estimate future diarrhea prevalence and design adaptation strategies. The model incorporates downscaled global climate models, water quality data, quantitative microbial risk assessment, and pathogen prevalence in an agent-based modeling framework incorporating precipitation and diarrhea etiology. It is informed using water quality and diarrhea data from Hubli-Dharwad, India-a city with an intermittent piped water supply exhibiting seasonal water quality variability vulnerable to climate change. We predict all-cause diarrhea prevalence to increase by 4.9% (Range: 1.5-9.0%) by 2011-2030, 11.9% (Range: 7.1-18.2%) by 2046-2065, and 18.2% (Range: 9.1-26.2%) by 2080-2099. Rainfall is an important modifying factor. Rotavirus prevalence is estimated to decline by 10.5% with Cryptosporidium and E. coli prevalence increasing by 9.9% and 6.3%, respectively, by 2080-2099 in this setting. These results suggest that ceramic water filters would be recommended as a climate adaptation strategy over chlorination. This work highlights the vulnerability of intermittent water supplies to climate change and the urgent need for improvements.
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Affiliation(s)
- Jonathan Mellor
- Department of Civil and Environmental Engineering, University of Connecticut , Storrs, Connecticut 06269, United States
| | | | - Ayse Ercumen
- Division of Epidemiology, University of California at Berkeley , Berkeley, California 94720, United States
| | - Julie Zimmerman
- Department of Chemical and Environmental Engineering, Yale University , New Haven, Connecticut 06511, United States
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Seasonality of water quality and diarrheal disease counts in urban and rural settings in south India. Sci Rep 2016; 6:20521. [PMID: 26867519 PMCID: PMC4751522 DOI: 10.1038/srep20521] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 01/05/2016] [Indexed: 11/30/2022] Open
Abstract
The study examined relationships among meteorological parameters, water quality and diarrheal disease counts in two urban and three rural sites in Tamil Nadu, India. Disease surveillance was conducted between August 2010 and March 2012; concurrently water samples from street-level taps in piped distribution systems and from household storage containers were tested for pH, nitrate, total dissolved solids, and total and fecal coliforms. Methodological advances in data collection (concurrent prospective disease surveillance and environmental monitoring) and analysis (preserving temporality within the data through time series analysis) were used to quantify independent effects of meteorological conditions and water quality on diarrheal risk. The utility of a local calendar in communicating seasonality is also presented. Piped distribution systems in the study area showed high seasonal fluctuations in water quality. Higher ambient temperature decreased and higher rainfall increased diarrheal risk with temperature being the predominant factor in urban and rainfall in rural sites. Associations with microbial contamination were inconsistent; however, disease risk in the urban sites increased with higher median household total coliform concentrations. Understanding seasonal patterns in health outcomes and their temporal links to environmental exposures may lead to improvements in prospective environmental and disease surveillance tailored to addressing public health problems.
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Antibiotic Resistance in Animal and Environmental Samples Associated with Small-Scale Poultry Farming in Northwestern Ecuador. mSphere 2016; 1:mSphere00021-15. [PMID: 27303705 PMCID: PMC4863614 DOI: 10.1128/msphere.00021-15] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/28/2015] [Indexed: 02/01/2023] Open
Abstract
In developing countries, small-scale poultry farming employing antibiotics as growth promoters is being advanced as an inexpensive source of protein and income. Here, we present the results of a large ecoepidemiological study examining patterns of antibiotic resistance (AR) in E. coli isolates from small-scale poultry production environments versus domestic environments in rural Ecuador, where such backyard poultry operations have become established over the past decade. Our previous research in the region suggests that introduction of AR bacteria through travel and commerce may be an important source of AR in villages of this region. This report extends the prior analysis by examining small-scale production chicken farming as a potential source of resistant strains. Our results suggest that AR strains associated with poultry production likely originate from sources outside the study area and that these outside sources might be a better place to target control efforts than local management practices. The effects of animal agriculture on the spread of antibiotic resistance (AR) are cross-cutting and thus require a multidisciplinary perspective. Here we use ecological, epidemiological, and ethnographic methods to examine populations of Escherichia coli circulating in the production poultry farming environment versus the domestic environment in rural Ecuador, where small-scale poultry production employing nontherapeutic antibiotics is increasingly common. We sampled 262 “production birds” (commercially raised broiler chickens and laying hens) and 455 “household birds” (raised for domestic use) and household and coop environmental samples from 17 villages between 2010 and 2013. We analyzed data on zones of inhibition from Kirby-Bauer tests, rather than established clinical breakpoints for AR, to distinguish between populations of organisms. We saw significantly higher levels of AR in bacteria from production versus household birds; resistance to either amoxicillin-clavulanate, cephalothin, cefotaxime, and gentamicin was found in 52.8% of production bird isolates and 16% of household ones. A strain jointly resistant to the 4 drugs was exclusive to a subset of isolates from production birds (7.6%) and coop surfaces (6.5%) and was associated with a particular purchase site. The prevalence of AR in production birds declined with bird age (P < 0.01 for all antibiotics tested except tetracycline, sulfisoxazole, and trimethoprim-sulfamethoxazole). Farming status did not impact AR in domestic environments at the household or village level. Our results suggest that AR associated with small-scale poultry farming is present in the immediate production environment and likely originates from sources outside the study area. These outside sources might be a better place to target control efforts than local management practices. IMPORTANCE In developing countries, small-scale poultry farming employing antibiotics as growth promoters is being advanced as an inexpensive source of protein and income. Here, we present the results of a large ecoepidemiological study examining patterns of antibiotic resistance (AR) in E. coli isolates from small-scale poultry production environments versus domestic environments in rural Ecuador, where such backyard poultry operations have become established over the past decade. Our previous research in the region suggests that introduction of AR bacteria through travel and commerce may be an important source of AR in villages of this region. This report extends the prior analysis by examining small-scale production chicken farming as a potential source of resistant strains. Our results suggest that AR strains associated with poultry production likely originate from sources outside the study area and that these outside sources might be a better place to target control efforts than local management practices.
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Lu J, Struewing I, Vereen E, Kirby AE, Levy K, Moe C, Ashbolt N. Molecular Detection of Legionella
spp. and their associations with Mycobacterium
spp., Pseudomonas aeruginosa
and amoeba hosts in a drinking water distribution system. J Appl Microbiol 2016; 120:509-21. [DOI: 10.1111/jam.12996] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 10/08/2015] [Accepted: 10/27/2015] [Indexed: 01/12/2023]
Affiliation(s)
- J. Lu
- U.S. EPA National Exposure Research Laboratory; Cincinnati OH USA
| | | | - E. Vereen
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - A. E. Kirby
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - K. Levy
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - C. Moe
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - N. Ashbolt
- School of Public Health; University of Alberta; Edmonton AB Canada
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24
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Luby SP, Halder AK, Huda TM, Unicomb L, Sirajul Islam M, Arnold BF, Johnston RB. Microbiological Contamination of Drinking Water Associated with Subsequent Child Diarrhea. Am J Trop Med Hyg 2015; 93:904-911. [PMID: 26438031 PMCID: PMC4703288 DOI: 10.4269/ajtmh.15-0274] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 08/07/2015] [Indexed: 11/07/2022] Open
Abstract
We used a prospective, longitudinal cohort enrolled as part of a program evaluation to assess the relationship between drinking water microbiological quality and child diarrhea. We included 50 villages across rural Bangladesh. Within each village field-workers enrolled a systematic random sample of 10 households with a child under the age of 3 years. Community monitors visited households monthly and recorded whether children under the age of 5 years had diarrhea in the preceding 2 days. Every 3 months, a research assistant visited the household and requested a water sample from the source or container used to provide drinking water to the child. Laboratory technicians measured the concentration of Escherichia coli in the water samples using membrane filtration. Of drinking water samples, 59% (2,273/3,833) were contaminated with E. coli. Of 12,192 monthly follow-up visits over 2 years, mothers reported that their child had diarrhea in the preceding 2 days in 1,156 (9.5%) visits. In a multivariable general linear model, the log10 of E. coli contamination of the preceding drinking water sample was associated with an increased prevalence of child diarrhea (prevalence ratio = 1.14, 95% CI = 1.05, 1.23). These data provide further evidence of the health benefits of improved microbiological quality of drinking water.
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Affiliation(s)
- Stephen P. Luby
- *Address correspondence to Stephen P. Luby, Division of Infectious Diseases, Stanford University, Yang and Yamazaki Environment and Energy Building (Y2E2), MC 4205, 473 Via Ortega, Stanford, CA 94305. E-mail:
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25
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Stoler J, Ahmed H, Asantewa Frimpong L, Bello M. Presence of Pseudomonas aeruginosa in coliform-free sachet drinking water in Ghana. Food Control 2015. [DOI: 10.1016/j.foodcont.2015.02.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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26
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Heitzinger K, Rocha CA, Quick RE, Montano SM, Tilley DH, Mock CN, Carrasco AJ, Cabrera RM, Hawes SE. "Improved" But Not Necessarily Safe: An Assessment of Fecal Contamination of Household Drinking Water in Rural Peru. Am J Trop Med Hyg 2015. [PMID: 26195455 DOI: 10.4269/ajtmh.14-0802] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The indicator used to measure progress toward the Millennium Development Goal (MDG) for water is access to an improved water supply. However, improved supplies are frequently fecally contaminated in developing countries. We examined factors associated with Escherichia coli contamination of improved water supplies in rural Pisco province, Peru. A random sample of 207 households with at least one child less than 5 years old was surveyed, and water samples from the source and storage container were tested for E. coli contamination. Although over 90% of households used an improved water source, 47% of source and 43% of stored water samples were contaminated with E. coli. Pouring or using a spigot to obtain water from the storage container instead of dipping a hand or object was associated with decreased risk of contamination of stored water (adjusted prevalence ratio [aPR] = 0.58, 95% confidence interval [CI] = 0.42, 0.80). Container cleanliness (aPR = 0.67, 95% CI = 0.45, 1.00) and correct handwashing technique (aPR = 0.62, 95% CI = 0.42, 0.90) were also associated with decreased contamination risk. These findings highlighted the limitations of improved water supplies as an indicator of safe water access. To ensure water safety in the home, household water treatment and improved hygiene, water handling, and storage practices should be promoted.
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Affiliation(s)
- Kristen Heitzinger
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Claudio A Rocha
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Robert E Quick
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Silvia M Montano
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Drake H Tilley
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Charles N Mock
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - A Jannet Carrasco
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Ricardo M Cabrera
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
| | - Stephen E Hawes
- Department of Epidemiology, University Of Washington, Seattle, Washington; Bacteriology Department, U.S. Naval Medical Research Unit No. 6, Callao, Peru; Waterborne Diseases Prevention Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Department of Environmental Health, Hospital San Juan de Dios, Ica Regional Ministry of Health, Pisco, Peru
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Abstract
The use of contaminated surface water continues to be a pressing issue in areas of the world where people lack improved drinking water sources. In northern coastal Ecuador, many communities rely on untreated surface water as their primary source of drinking water. We undertook a study to explore how microscale river hydrodynamics affect microbial water quality at community water collection locations at three rivers with varying stream velocity and turbidity profiles. To examine how the distance from river shore and physiochemical water quality variables affect microbial contamination levels in the rivers; we collected a total of 355 water samples within six villages on three rivers; and tested for Escherichia coli concentrations using the IDEXX Quanti-tray method. We found that log10E. coli concentrations decreased with increasing distance from shore (β = −0.017; p = 0.003). Water in the main channel had E. coli concentrations on average 0.12 log10 lower than within eddies along the river shore and 0.27 log10 lower between the sample closest to shore and any sample >6 m from the shore. Higher E. coli concentrations were also significantly associated with increased turbidity (β = 0.003; p < 0.0001) and decreased dissolved oxygen levels (β = −0.310; p < 0.0001). The results of this study can help inform community members about the safest locations to collect drinking water and also provide information on watershed scale transport of microbial contaminants between villages.
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Alqahtani JM, Asaad AM, Ahmed EM, Qureshi MA. Drinking water quality and public health in Southwestern Saudi Arabia: The need for a national monitoring program. J Family Community Med 2015; 22:19-24. [PMID: 25657607 PMCID: PMC4317990 DOI: 10.4103/2230-8229.149581] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Aim of the Study: The aim was to investigate the bacteriological quality of drinking water, and explore the factors involved in the knowledge of the public about the quality of drinking water in Najran region, Saudi Arabia. Study Design: A cross-sectional descriptive study. Materials and Methods: A total of 160 water samples were collected. Total coliforms, fecal coliform, and fecal streptococci were counted using Most Probable Number method. The bacterial genes lacZ and uidA specific to total coliforms and Escherichia coli, respectively, were detected using multiplex polymerase chain reaction. An interview was conducted with 1200 residents using a questionnaire. Results: Total coliforms were detected in 8 (20%) of 40 samples from wells, 13 (32.5%) of 40 samples from tankers, and 55 (68.8%) of 80 samples from roof tanks. Twenty (25%) and 8 (10%) samples from roof tanks were positive for E. coli and Streptococcus faecalis, respectively. Of the 1200 residents participating in the study, 10%, 45.5%, and 44.5% claimed that they depended on municipal water, bottled water, and well water, respectively. The majority (95.5%) reported the use of roof water tanks as a source of water supply in their homes. Most people (80%) believed that drinking water transmitted diseases. However, only 25% of them participated in educational programs on the effect of polluted water on health. Conclusions: Our results could help health authorities consider a proper regular monitoring program and a sustainable continuous assessment of the quality of well water. In addition, this study highlights the importance of the awareness and educational programs for residents on the effect of polluted water on public health.
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Affiliation(s)
- Jobran M Alqahtani
- Department of Pediatric, College of Applied Medical Sciences, Najran University, Najran, Kingdom of Saudi Arabia
| | - Ahmed M Asaad
- Department of Microbiology, College of Medicine, Najran University, Najran, Kingdom of Saudi Arabia
| | - Essam M Ahmed
- Department of Microbiology, College of Medicine, Najran University, Najran, Kingdom of Saudi Arabia
| | - Mohamed A Qureshi
- Department of Microbiology, College of Applied Medical Sciences, Najran University, Najran, Kingdom of Saudi Arabia
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29
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Gentry-Shields J, Myers K, Pisanic N, Heaney C, Stewart J. Hepatitis E virus and coliphages in waters proximal to swine concentrated animal feeding operations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 505:487-93. [PMID: 25461050 PMCID: PMC4514618 DOI: 10.1016/j.scitotenv.2014.10.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/30/2014] [Accepted: 10/01/2014] [Indexed: 04/15/2023]
Abstract
North Carolina is the second leading state in pork production in the United States, with over 10 million swine. Swine manure in NC is typically collected and stored in open-pit lagoons before the liquid waste is sprayed onto agricultural fields for disposal. Components of this waste may be able to impact surface water quality with the potential for human exposure. This study examined viruses of public health concern in creeks adjacent to swine concentrated animal feeding operation (CAFO) spray fields. Surface water samples (n=154) were collected from public access waters in proximity to swine CAFO spray fields for six months and were tested for hepatitis E virus (HEV) and coliphages. HEV was detected in one sample. Somatic coliphages were detected in 98% of samples (geometric mean 24 ± 4.1 PFU per 100 ml), and F+ coliphages were detected in 85% of samples (geometric mean 6.8 ± 5.0 PFU per 100 ml). Only 3% (21) of the F+ coliphage isolates were RNA phage, and all of the F+ RNA coliphages belonged to genogroup I. Although the pervasiveness of swine CAFOs in this area prevented a comparison with samples from un-impacted sites, the near ubiquity of coliphages, as well as the presence of HEV, suggests that current waste management practices may be associated with the dissemination of viruses of public health concern in waters proximal to CAFO spray fields.
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Affiliation(s)
- Jennifer Gentry-Shields
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599-7431, USA.
| | - Kevin Myers
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599-7431, USA.
| | - Nora Pisanic
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
| | - Christopher Heaney
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
| | - Jill Stewart
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599-7431, USA.
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Gruber JS, Ercumen A, Colford JM. Coliform bacteria as indicators of diarrheal risk in household drinking water: systematic review and meta-analysis. PLoS One 2014; 9:e107429. [PMID: 25250662 PMCID: PMC4175079 DOI: 10.1371/journal.pone.0107429] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 06/18/2014] [Indexed: 01/24/2023] Open
Abstract
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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Affiliation(s)
- Joshua S. Gruber
- Division of Epidemiology, University of California, Berkeley, California, United States of America
| | - Ayse Ercumen
- Division of Epidemiology, University of California, Berkeley, California, United States of America
| | - John M. Colford
- Division of Epidemiology, University of California, Berkeley, California, United States of America
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31
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Golberg A, Linshiz G, Kravets I, Stawski N, Hillson NJ, Yarmush ML, Marks RS, Konry T. Cloud-enabled microscopy and droplet microfluidic platform for specific detection of Escherichia coli in water. PLoS One 2014; 9:e86341. [PMID: 24475107 PMCID: PMC3903517 DOI: 10.1371/journal.pone.0086341] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 12/12/2013] [Indexed: 12/13/2022] Open
Abstract
We report an all-in-one platform – ScanDrop – for the rapid and specific capture, detection, and identification of bacteria in drinking water. The ScanDrop platform integrates droplet microfluidics, a portable imaging system, and cloud-based control software and data storage. The cloud-based control software and data storage enables robotic image acquisition, remote image processing, and rapid data sharing. These features form a “cloud” network for water quality monitoring. We have demonstrated the capability of ScanDrop to perform water quality monitoring via the detection of an indicator coliform bacterium, Escherichia coli, in drinking water contaminated with feces. Magnetic beads conjugated with antibodies to E. coli antigen were used to selectively capture and isolate specific bacteria from water samples. The bead-captured bacteria were co-encapsulated in pico-liter droplets with fluorescently-labeled anti-E. coli antibodies, and imaged with an automated custom designed fluorescence microscope. The entire water quality diagnostic process required 8 hours from sample collection to online-accessible results compared with 2–4 days for other currently available standard detection methods.
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Affiliation(s)
- Alexander Golberg
- Centre for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Shriners Burns Institute, Boston, Massachusetts, United States of America
| | - Gregory Linshiz
- Fuels Synthesis Division, Joint BioEnergy Institute, Emeryville, California, United States of America ; Physical BioSciences Division, Lawrence Berkeley National Labs, Berkeley, California, United States of America ; DOE Joint Genome Institute, Walnut Creek, California, United States of America
| | - Ilia Kravets
- Department of Computer Science, Technion Institute of Technology, Haifa, Israel
| | - Nina Stawski
- Fuels Synthesis Division, Joint BioEnergy Institute, Emeryville, California, United States of America ; Physical BioSciences Division, Lawrence Berkeley National Labs, Berkeley, California, United States of America
| | - Nathan J Hillson
- Fuels Synthesis Division, Joint BioEnergy Institute, Emeryville, California, United States of America ; Physical BioSciences Division, Lawrence Berkeley National Labs, Berkeley, California, United States of America ; DOE Joint Genome Institute, Walnut Creek, California, United States of America
| | - Martin L Yarmush
- Centre for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Shriners Burns Institute, Boston, Massachusetts, United States of America ; Department of Biomedical Engineering, Rutgers University, New Jersey, United States of America
| | - Robert S Marks
- Department of Biotechnology Engineering, The National Institute of Biotechnology in Negev, Ben Gurion University, Beer-Sheva, Israel ; School of Materials Science and Engineering, Nanyang Technological University, Singapore ; NRF CREATE program for Nanomaterials in Energy and Water Management, Singapore
| | - Tania Konry
- Department of Pharmaceutical Sciences, School of Pharmacy Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts, United States of America
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32
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Shaheed A, Orgill J, Montgomery MA, Jeuland MA, Brown J. Why "improved" water sources are not always safe. Bull World Health Organ 2014; 92:283-9. [PMID: 24700996 DOI: 10.2471/blt.13.119594] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 11/26/2013] [Accepted: 11/28/2013] [Indexed: 11/27/2022] Open
Abstract
Existing and proposed metrics for household drinking-water services are intended to measure the availability, safety and accessibility of water sources. However, these attributes can be highly variable over time and space and this variation complicates the task of creating and implementing simple and scalable metrics. In this paper, we highlight those factors - especially those that relate to so-called improved water sources - that contribute to variability in water safety but may not be generally recognized as important by non-experts. Problems in the provision of water in adequate quantities and of adequate quality - interrelated problems that are often influenced by human behaviour - may contribute to an increased risk of poor health. Such risk may be masked by global water metrics that indicate that we are on the way to meeting the world's drinking-water needs. Given the complexity of the topic and current knowledge gaps, international metrics for access to drinking water should be interpreted with great caution. We need further targeted research on the health impacts associated with improvements in drinking-water supplies.
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Affiliation(s)
- Ameer Shaheed
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, England
| | - Jennifer Orgill
- Sanford School of Public Policy, Duke University, Durham, United States of America (USA)
| | - Maggie A Montgomery
- Water, Sanitation and Health Unit, World Health Organization, Geneva, Switzerland
| | - Marc A Jeuland
- Sanford School of Public Policy, Duke University, Durham, United States of America (USA)
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Mason Building, 790 Atlantic Drive, Atlanta, GA 30332-0355, USA
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Mattioli MC, Boehm AB, Davis J, Harris AR, Mrisho M, Pickering AJ. Enteric pathogens in stored drinking water and on caregiver's hands in Tanzanian households with and without reported cases of child diarrhea. PLoS One 2014; 9:e84939. [PMID: 24392161 PMCID: PMC3879350 DOI: 10.1371/journal.pone.0084939] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Accepted: 11/29/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Diarrhea is one of the leading causes of mortality in young children. Diarrheal pathogens are transmitted via the fecal-oral route, and for children the majority of this transmission is thought to occur within the home. However, very few studies have documented enteric pathogens within households of low-income countries. METHODS AND FINDINGS The presence of molecular markers for three enteric viruses (enterovirus, adenovirus, and rotavirus), seven Escherichia coli virulence genes (ECVG), and human-specific Bacteroidales was assessed in hand rinses and household stored drinking water in Bagamoyo, Tanzania. Using a matched case-control study design, we examined the relationship between contamination of hands and water with these markers and child diarrhea. We found that the presence of ECVG in household stored water was associated with a significant decrease in the odds of a child within the home having diarrhea (OR = 0.51; 95% confidence interval 0.27-0.93). We also evaluated water management and hygiene behaviors. Recent hand contact with water or food was positively associated with detection of enteric pathogen markers on hands, as was relatively lower volumes of water reportedly used for daily hand washing. Enteropathogen markers in stored drinking water were more likely found among households in which the markers were also detected on hands, as well as in households with unimproved water supply and sanitation infrastructure. CONCLUSIONS The prevalence of enteric pathogen genes and the human-specific Bacteroidales fecal marker in stored water and on hands suggests extensive environmental contamination within homes both with and without reported child diarrhea. Better stored water quality among households with diarrhea indicates caregivers with sick children may be more likely to ensure safe drinking water in the home. Interventions to increase the quantity of water available for hand washing, and to improve food hygiene, may reduce exposure to enteric pathogens in the domestic environment.
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Affiliation(s)
- Mia Catharine Mattioli
- Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University, Stanford, California, United States of America
| | - Alexandria B. Boehm
- Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University, Stanford, California, United States of America
| | - Jennifer Davis
- Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University, Stanford, California, United States of America
- Woods Institute for the Environment, Stanford University, Stanford, California, United States of America
| | - Angela R. Harris
- Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University, Stanford, California, United States of America
| | - Mwifadhi Mrisho
- Ifakara Health Institute, Bagamoyo Research and Training Unit, Bagamoyo, Tanzania
| | - Amy J. Pickering
- Environmental and Water Studies, Department of Civil and Environmental Engineering, Stanford University, Stanford, California, United States of America
- Woods Institute for the Environment, Stanford University, Stanford, California, United States of America
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34
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Mohanty SK, Torkelson AA, Dodd H, Nelson KL, Boehm AB. Engineering solutions to improve the removal of fecal indicator bacteria by bioinfiltration systems during intermittent flow of stormwater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:10791-8. [PMID: 23721343 DOI: 10.1021/es305136b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Bioinfiltration systems facilitate the infiltration of urban stormwater into soil and reduce high flow events and flooding. Stormwater carries a myriad of pollutants including fecal indicator bacteria (FIB). Significant knowledge gaps exist about the ability of bioinfiltration systems to remove and retain FIB. The present study investigates the ability of model, simplified bioinfiltration systems containing quartz sand and iron oxide-coated quartz sand (IOCS) to remove two FIB (Enterococcus faecalis and Escherichia coli) suspended in synthetic stormwater with and without natural organic matter (NOM) as well as the potential for accumulated FIB to be remobilized during intermittent flow. The experiments were conducted in two phases: (1) the saturated columns packed with either sand or IOCS were contaminated by injecting stormwater with bacteria followed by injection of sterile stormwater and (2) the contaminated columns were subjected to intermittent infiltration of sterile stormwater preceded by a pause during which columns were either kept saturated or drained by gravity. During intermittent flow, fewer bacteria were released from the saturated column compared to the column drained by gravity: 12% of attached E. coli and 3% of attached Ent. faecalis were mobilized from the drained sand column compared to 3% of attached E. coli and 2% attached Ent. faecalis mobilized from the saturated sand column. Dry and wet cycles introduce moving air-water interfaces that can scour bacteria from grain surfaces. During intermittent flows, less than 0.2% of attached bacteria were mobilized from IOCS, which bound both bacteria irreversibly in the absence of NOM. Addition of NOM, however, increased bacterial mobilization from IOCS: 50% of attached E. coli and 8% of attached Ent. faecalis were released from IOCS columns during draining and rewetting. Results indicate that using geomedia such as IOCS that promote irreversible attachment of bacteria, and maintaining saturated condition, could minimize the mobilization of previous attached bacteria from bioinfiltration systems, although NOM may significantly decrease these benefits.
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Affiliation(s)
- Sanjay K Mohanty
- Dept. of Civil and Environmental Engineering, Stanford University , Stanford, California, United States
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Gruber JS, Reygadas F, Arnold BF, Ray I, Nelson K, Colford JM. A stepped wedge, cluster-randomized trial of a household UV-disinfection and safe storage drinking water intervention in rural Baja California Sur, Mexico. Am J Trop Med Hyg 2013; 89:238-245. [PMID: 23732255 PMCID: PMC3741243 DOI: 10.4269/ajtmh.13-0017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In collaboration with a local non-profit organization, this study evaluated the expansion of a program that promoted and installed Mesita Azul, an ultraviolet-disinfection system designed to treat household drinking water in rural Mexico. We conducted a 15-month, cluster-randomized stepped wedge trial by randomizing the order in which 24 communities (444 households) received the intervention. We measured primary outcomes (water contamination and diarrhea) during seven household visits. The intervention increased the percentage of households with access to treated and safely stored drinking water (23–62%), and reduced the percentage of households with Escherichia coli contaminated drinking water (risk difference (RD): −19% [95% CI: −27%, −14%]). No significant reduction in diarrhea was observed (RD: −0.1% [95% CI: −1.1%, 0.9%]). We conclude that household water quality improvements measured in this study justify future promotion of the Mesita Azul, and that future studies to measure its health impact would be valuable if conducted in populations with higher diarrhea prevalence.
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Affiliation(s)
- Joshua S. Gruber
- *Address correspondence to Joshua S. Gruber, University of California, Berkeley, Division of Epidemiology, 101 Haviland Hall, Berkeley, CA 94720-7358. E-mail:
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36
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Khush RS, Arnold BF, Srikanth P, Sudharsanam S, Ramaswamy P, Durairaj N, London AG, Ramaprabha P, Rajkumar P, Balakrishnan K, Colford JM. H2S as an indicator of water supply vulnerability and health risk in low-resource settings: a prospective cohort study. Am J Trop Med Hyg 2013; 89:251-9. [PMID: 23716404 DOI: 10.4269/ajtmh.13-0067] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In this large-scale longitudinal study conducted in rural Southern India, we compared a presence/absence hydrogen sulfide (H2S) test with quantitative assays for total coliforms and Escherichia coli as measures of water quality, health risk, and water supply vulnerability to microbial contamination. None of the three indicators showed a significant association with child diarrhea. The presence of H2S in a water sample was associated with higher levels of total coliform species that may have included E. coli but that were not restricted to E. coli. In addition, we observed a strong relationship between the percent positive H2S test results and total coliform levels among water source samples (R(2) = 0.87). The consistent relationships between H2S and total coliform levels indicate that presence/absence of H2S tests provide a cost-effective option for assessing both the vulnerability of water supplies to microbial contamination and the results of water quality management and risk mitigation efforts.
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Affiliation(s)
- Ranjiv S Khush
- The Aquaya Institute, San Francisco, California 94129, USA.
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