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Momba MNB, Mogane B, Kachienga LO, Kamika I, Ngobeni-Nyambi R. Distribution of host-specific Bacteriodales marker genes in water sources of selected rural areas of Vhembe District, South Africa. Sci Rep 2024; 14:19758. [PMID: 39187527 PMCID: PMC11347707 DOI: 10.1038/s41598-024-68771-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 07/29/2024] [Indexed: 08/28/2024] Open
Abstract
Access to safe drinking water sources and appropriate sanitation facilities remains a dream in low and middle-income countries including South Africa. This study identified the origin of faecal pollution by using quantitative polymerase chain reaction (qPCR) targeting host-specific Bacteroidales genetic markers to track the distribution of human-specific (BacHum) and animal-specific (cattle-BacCow, chicken-Cytb, pig-Pig-2-Bac, dog-BacCan) markers in water sources used by rural communities of the Vhembe District Municipality (VDM). Results revealed the prevalence of BacHum, BacCow, and BacCan in all surface water sources in Thulamela Local Municipality (TLM) and Collins Chabane Local Municipality (CLM) during wet (100%) and dry seasons (50-75%). Cytb was not detected in untreated spring water in TLM and CLM, and Pig-2-Bac was not detected in untreated hand-dug well water in TLM during both seasons. Household-level analysis detected Cytb (28.8% wet, 17.5% dry), BacHum (34.4% wet, 25% dry for Pig-2-Bac) in stored untreated spring water in CLM, and Cytb (42.9% wet, 28.5% dry) in untreated hand-dug well water in TLM. Despite differences in detection frequencies of host-specific Bacteroidales, the study highlights the public health concern of faecal pollution in rural VDM households.
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Affiliation(s)
- Maggy Ndombo Benteke Momba
- Department of Environmental, Water and Earth Sciences, Arcadia Campus, Tshwane University of Technology, 175 Nelson Mandela Avenue, Arcadia, Pretoria, 0001, South Africa.
| | - Barbara Mogane
- Department of Environmental, Water and Earth Sciences, Arcadia Campus, Tshwane University of Technology, 175 Nelson Mandela Avenue, Arcadia, Pretoria, 0001, South Africa
| | - Leonard Owino Kachienga
- Department of Environmental, Water and Earth Sciences, Arcadia Campus, Tshwane University of Technology, 175 Nelson Mandela Avenue, Arcadia, Pretoria, 0001, South Africa
| | - Ilunga Kamika
- Department of Environmental Sciences, School of Environmental Science, College of Agriculture and Environmental Sciences, Faculty of Sciences, Florida Campus, University of South Africa, Florida, Roodepoort, 1710, South Africa
| | - Renay Ngobeni-Nyambi
- Department of Microbiology, Stellenbosch University, Private Bag, X1, Mitieland, 7602, South Africa
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2
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Hinds JB, Garg T, Hutmacher S, Nguyen A, Zheng Z, Griffith J, Steele J, González Fernández A, Schiff K. Assessing the defecation practices of unsheltered individuals and their contributions to microbial water quality in an arid, urban watershed. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170708. [PMID: 38336079 DOI: 10.1016/j.scitotenv.2024.170708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/12/2024] [Accepted: 02/03/2024] [Indexed: 02/12/2024]
Abstract
Outdoor defecation by people experiencing homelessness is frequently perceived as a potentially large source of human fecal pollution and a significant source of health risk in urban waterbodies with recreational contact. The goal of this study was to count the number of people experiencing homelessness and quantifies their sanitation habits in an urban river corridor setting, then use this information for estimating human fecal pollutant loading on a watershed scale. Two types of census counts were conducted including periodic point-in-time counts over six years and weekly counts of encampments. While the population census varied from count-to-count, the range of population estimates in the river corridor varied from 109 to 349 individuals during the six-year span, which mirrored the weekly counts of encampments. A face-to-face survey of people experiencing homelessness assessed the sanitation habits of the unsheltered population (N = 63), including outdoor defecation frequency and containment practices. Overall, 95 % of survey respondents reported defecating outdoors; 36 % practiced outdoor defecation between 4 and 7 days/week and 27 % practiced outdoor defecation <1 day/week. Of those that did practice outdoor defecation, 75 % contained their feces in a bucket or bag, thereby limiting fecal material contributions to the river; 6.7 % reported defecating on low ground near the river that could wash off when flood waters rise during a storm event. Only a single survey respondent reported defecating directly into the river. Based on literature values for average HF183 output for an adult human, and the average rainfall in the urban watershed, the total watershed contribution of HF183 averaged 1.2 × 1010 gene copies per storm event (95 % CI: 0.9 × 1010-1.6 × 1010) along the 41 km stretch of river in this study. This human fecal loading estimate is at least two orders of magnitude less than cumulative HF183 loading from all human sources measured at the bottom of the watershed.
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Affiliation(s)
- J B Hinds
- Department of Urban Studies and Planning, University of California San Diego, La Jolla, CA, USA
| | - Teevrat Garg
- School of Global Policy and Strategy, University of California San Diego, La Jolla, CA, USA
| | | | - Andrew Nguyen
- Department of Urban Studies and Planning, University of California San Diego, La Jolla, CA, USA
| | - Zhongqi Zheng
- Department of Urban Studies and Planning, University of California San Diego, La Jolla, CA, USA
| | - John Griffith
- Southern California Coastal Water Research Project, Costa Mesa, CA, USA
| | - Joshua Steele
- Southern California Coastal Water Research Project, Costa Mesa, CA, USA
| | | | - Kenneth Schiff
- Southern California Coastal Water Research Project, Costa Mesa, CA, USA.
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3
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Rao G, Kahler A, Voth-Gaeddert LE, Cranford H, Libbey S, Galloway R, Molinari NA, Ellis EM, Yoder JS, Mattioli MC, Ellis BR. Microbial Characterization, Factors Contributing to Contamination, and Household Use of Cistern Water, U.S. Virgin Islands. ACS ES&T WATER 2022; 2:2634-2644. [PMID: 36530952 PMCID: PMC9745795 DOI: 10.1021/acsestwater.2c00389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/13/2022] [Accepted: 09/20/2022] [Indexed: 05/09/2023]
Abstract
Households in the United States Virgin Islands (USVI) heavily rely on roof-harvested rainwater stored in cisterns for their daily activities. However, there are insufficient data on cistern water microbiological and physicochemical characteristics to inform appropriate cistern water management. Cistern and kitchen tap water samples were collected from 399 geographically representative households across St. Croix, St. Thomas, and St. John and an administered survey captured household site and cistern characteristics and water use behaviors. Water samples were analyzed for Escherichia coli by culture, and a subset of cistern water samples (N = 47) were analyzed for Salmonella, Naegleria fowleri, pathogenic Leptospira, Cryptosporidium, Giardia, and human-specific fecal contamination using real-time polymerase chain reaction (PCR). Associations between E. coli cistern contamination and cistern and site characteristics were evaluated to better understand possible mechanisms of contamination. E. coli was detected in 80% of cistern water samples and in 58% of kitchen tap samples. For the subset of samples tested by PCR, at least one of the pathogens was detected in 66% of cisterns. Our results suggest that covering overflow pipes with screens, decreasing animal presence at the household, and preventing animals or insects from entering the cisterns can decrease the likelihood of E. coli contamination in USVI cistern water.
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Affiliation(s)
- Gouthami Rao
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Amy Kahler
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Lee E. Voth-Gaeddert
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Hannah Cranford
- United
States Virgin Islands Department of Health, St. Croix, U.S. Virgin Islands 00820, United States
| | - Stephen Libbey
- Love
City Strong, St. John, U.S. Virgin Islands 00830, United States
| | - Renee Galloway
- Division
of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Noelle-Angelique Molinari
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Esther M. Ellis
- United
States Virgin Islands Department of Health, St. Croix, U.S. Virgin Islands 00820, United States
| | - Jonathan S. Yoder
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Mia C. Mattioli
- Division
of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30329, United States
| | - Brett R. Ellis
- United
States Virgin Islands Department of Health, St. Croix, U.S. Virgin Islands 00820, United States
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4
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Gerrity D, Papp K, Dickenson E, Ejjada M, Marti E, Quinones O, Sarria M, Thompson K, Trenholm RA. Characterizing the chemical and microbial fingerprint of unsheltered homelessness in an urban watershed. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 840:156714. [PMID: 35709998 DOI: 10.1016/j.scitotenv.2022.156714] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/08/2022] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
Unsheltered homelessness is rapidly becoming a critical issue in many cities worldwide. The worsening situation not only highlights the socioeconomic plight, but it also raises awareness of ancillary issues such as the potential implications for urban water quality. The objective of this study was to simultaneously leverage diverse source tracking tools to develop a chemical and microbial fingerprint describing the relative contribution of direct human inputs into Las Vegas' tributary washes. By evaluating a wide range of urban water matrices using general water quality parameters, fecal indicator bacteria (FIB), human-associated microbial markers [e.g., HF183, crAssphage, and pepper mild mottle virus (PMMoV)], 16S rRNA gene sequencing data, and concentrations of 52 anthropogenic trace organic compounds (TOrCs), this study was able to differentiate principal sources of these constituents, including contributions from unsheltered homelessness. For example, HF183 (31% vs. 0%), crAssphage (61% vs. 5%), and PMMoV (72% vs. 55%) were more frequently detected in tributary washes with higher homeless census counts vs. 'control' tributary washes. Illicit drugs or their metabolites (e.g., heroin, acetylmorphine, amphetamine, and cocaine) and select TOrCs (e.g., acetaminophen, caffeine, ibuprofen, and naproxen) were also detected more frequently and at higher concentrations in the more anthropogenically-impacted washes. These data can be used to raise awareness of the shared interests between the broader community and those who are experiencing homelessness, notably the importance of protecting environmental health and water quality. Ultimately, this may lead to more rapid adoption of proven strategies for achieving functional zero homelessness, or at least additional resources for unsheltered individuals.
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Affiliation(s)
- Daniel Gerrity
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States; Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, P.O. Box 454015, Las Vegas, NV 89154-4015, United States.
| | - Katerina Papp
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States
| | - Eric Dickenson
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States
| | - Meena Ejjada
- Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, P.O. Box 454015, Las Vegas, NV 89154-4015, United States
| | - Erica Marti
- Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, P.O. Box 454015, Las Vegas, NV 89154-4015, United States
| | - Oscar Quinones
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States
| | - Mayra Sarria
- Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, P.O. Box 454015, Las Vegas, NV 89154-4015, United States
| | - Kyle Thompson
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States; Carollo Engineers, 8911 N. Capital of Texas Hwy, Austin, TX 78759, United States
| | - Rebecca A Trenholm
- Applied Research and Development Center, Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, United States
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Detangling Seasonal Relationships of Fecal Contamination Sources and Correlates with Indicators in Michigan Watersheds. Microbiol Spectr 2022; 10:e0041522. [PMID: 35730960 PMCID: PMC9431008 DOI: 10.1128/spectrum.00415-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite the widely acknowledged public health impacts of surface water fecal contamination, there is limited understanding of seasonal effects on (i) fate and transport processes and (ii) the mechanisms by which they contribute to water quality impairment. Quantifying relationships between land use, chemical parameters, and fecal bacterial concentrations in watersheds can help guide the monitoring and control of microbial water quality and explain seasonal differences. The goals of this study were to (i) identify seasonal differences in Escherichia coli and Bacteroides thetaiotaomicron concentrations, (ii) evaluate environmental drivers influencing microbial contamination during baseflow, snowmelt, and summer rain seasons, and (iii) relate seasonal changes in B. thetaiotaomicron to anticipated gastrointestinal infection risks. Water chemistry data collected during three hydroclimatic seasons from 64 Michigan watersheds were analyzed using seasonal linear regression models with candidate variables including crop and land use proportions, prior precipitation, chemical parameters, and variables related to both wastewater treatment and septic usage. Adaptive least absolute shrinkage and selection operator (LASSO) linear regression with bootstrapping was used to select explanatory variables and estimate coefficients. Regardless of season, wastewater treatment plant and septic system usage were consistently selected in all primary models for B. thetaiotaomicron and E. coli. Chemistry and precipitation-related variable selection depended upon season and organism. These results suggest a link between human pollution (e.g., septic systems) and microbial water quality that is dependent on flow regime. IMPORTANCE In this study, a data set of 64 Michigan watersheds was utilized to gain insights into fecal contamination sources, drivers, and chemical correlates across seasons for general E. coli and human-specific fecal indicators. Results reaffirmed a link between human-specific sources (e.g., septic systems) and microbial water quality. While the importance of human sources of fecal contamination and fate and transport variables (e.g., precipitation) remain important across seasons, this study provides evidence that fate and transport mechanisms vary with seasonal hydrologic condition and microorganism source. This study contributes to a body of research that informs prioritization of fecal contamination source control and surveillance strategy development to reduce the public health burden of surface water fecal contamination.
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6
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Application of fast expectation-maximization microbial source tracking to discern fecal contamination in rivers exposed to low fecal inputs. J Microbiol 2022; 60:594-601. [DOI: 10.1007/s12275-022-1651-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/11/2022] [Accepted: 03/15/2022] [Indexed: 10/18/2022]
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7
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Hachad M, Lanoue M, Vo Duy S, Villlemur R, Sauvé S, Prévost M, Dorner S. Locating illicit discharges in storm sewers in urban areas using multi-parameter source tracking: Field validation of a toolbox composite index to prioritize high risk areas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 811:152060. [PMID: 34861306 DOI: 10.1016/j.scitotenv.2021.152060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/24/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
In urban areas served by separate sewerage systems, illicit connections to the storm drain system from residences or commercial establishments are frequent whether these misconnections were made accidentally or deliberately. As a result, untreated and contaminated wastewater enters into storm sewers leading to pollution of receiving waters and non-compliance with water quality standards. Typical procedures for detecting illicit connections to the storm sewer system are time consuming and expensive, especially in a highly urbanised area. In this study, we investigated the use of human wastewater micropollutants WWMPs (caffeine, theophylline, and carbamazepine) and advanced DNA molecular markers (human specific Bacteroides HF183 and mitochondrial DNA) as anthropogenic tracers in order to assist identifying potential cross connections. Water samples from storm outfalls and storm sewer pipes in three urban subcatchments were collected in dry weather from 2013 to 2018. All samples contained various concentrations of these markers especially HF183, caffeine and theophylline, suggesting that the storm pipe system studied is widely contaminated by sanitary sewers. None of the traditional indicators or markers tested is sufficient alone to determine the origin of fecal pollution. In a highly urbanised area, the combination of at least three specific human markers was needed in order to locate the residential section with likely misconnections. The human specific Bacteroides HF183, and theophylline appeared to be the most effective markers (along with E. coli) of crossconnections, whereas carbamazepine can provide an indication of contamination through sanitary sewer exfiltration. A composite sewer cross-connection index was developed, and eight misconnected houses were identified and corrected. The index approach enables the reduction of false positives that could lead to expensive interventions to identify cross-connected households. The results show the multiparameter source tracking toolbox as an effective method to identify sewer cross connections for sustainable storm water management.
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Affiliation(s)
- Mounia Hachad
- Civil, Geological and Mining Engineering Department, Polytechnique de Montréal, CP 6079, succ. Centre-Ville, Montréal, QC H3C 3A7, Canada.
| | - Martine Lanoue
- City of Laval, soutien technique eau et salubrité, service de l'environnement et de l'écocitoyenneté, 480, Boulevard Armand-Frappier, Laval, QC H7V 3Z4, Canada
| | - Sung Vo Duy
- Department of Chemistry, Université de Montréal, P.O. Box 6128, succ, Centre-Ville, Montréal, QC H3C 3J7, Canada
| | - Richard Villlemur
- Institut National de la Recherche Scientifique, Centre Armand-Frappier Santé Biotechnologie, 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada
| | - Sébastien Sauvé
- Department of Chemistry, Université de Montréal, P.O. Box 6128, succ, Centre-Ville, Montréal, QC H3C 3J7, Canada
| | - Michèle Prévost
- Civil, Geological and Mining Engineering Department, Polytechnique de Montréal, CP 6079, succ. Centre-Ville, Montréal, QC H3C 3A7, Canada; NSERC Industrial Chair on Drinking Water, Civil, Geological and Mining Engineering Department, Polytechnique de Montréal, QC, Canada
| | - Sarah Dorner
- Civil, Geological and Mining Engineering Department, Polytechnique de Montréal, CP 6079, succ. Centre-Ville, Montréal, QC H3C 3A7, Canada; Canada Research Chair in Microbial Contaminant Dynamics in Source Waters, Civil, Geological and Mining Engineering Department, Polytechnique de Montréal, QC, Canada
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8
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Ahmed W, Simpson SL, Bertsch PM, Bibby K, Bivins A, Blackall LL, Bofill-Mas S, Bosch A, Brandão J, Choi PM, Ciesielski M, Donner E, D'Souza N, Farnleitner AH, Gerrity D, Gonzalez R, Griffith JF, Gyawali P, Haas CN, Hamilton KA, Hapuarachchi HC, Harwood VJ, Haque R, Jackson G, Khan SJ, Khan W, Kitajima M, Korajkic A, La Rosa G, Layton BA, Lipp E, McLellan SL, McMinn B, Medema G, Metcalfe S, Meijer WG, Mueller JF, Murphy H, Naughton CC, Noble RT, Payyappat S, Petterson S, Pitkänen T, Rajal VB, Reyneke B, Roman FA, Rose JB, Rusiñol M, Sadowsky MJ, Sala-Comorera L, Setoh YX, Sherchan SP, Sirikanchana K, Smith W, Steele JA, Sabburg R, Symonds EM, Thai P, Thomas KV, Tynan J, Toze S, Thompson J, Whiteley AS, Wong JCC, Sano D, Wuertz S, Xagoraraki I, Zhang Q, Zimmer-Faust AG, Shanks OC. Minimizing errors in RT-PCR detection and quantification of SARS-CoV-2 RNA for wastewater surveillance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 805:149877. [PMID: 34818780 PMCID: PMC8386095 DOI: 10.1016/j.scitotenv.2021.149877] [Citation(s) in RCA: 123] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/20/2021] [Accepted: 08/20/2021] [Indexed: 05/18/2023]
Abstract
Wastewater surveillance for pathogens using reverse transcription-polymerase chain reaction (RT-PCR) is an effective and resource-efficient tool for gathering community-level public health information, including the incidence of coronavirus disease-19 (COVID-19). Surveillance of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in wastewater can potentially provide an early warning signal of COVID-19 infections in a community. The capacity of the world's environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is increasing rapidly. However, there are no standardized protocols or harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can cause false-positive and false-negative errors in the surveillance of SARS-CoV-2 RNA in wastewater, culminating in recommended strategies that can be implemented to identify and mitigate some of these errors. Recommendations include stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, PCR inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly when the incidence of SARS-CoV-2 in wastewater is low. Corrective and confirmatory actions must be in place for inconclusive results or results diverging from current trends (e.g., initial onset or reemergence of COVID-19 in a community). It is also prudent to perform interlaboratory comparisons to ensure results' reliability and interpretability for prospective and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization and detection for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance continues to be demonstrated during this global crisis. In the future, wastewater should also play an important role in the surveillance of a range of other communicable diseases.
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Affiliation(s)
- Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia.
| | | | - Paul M Bertsch
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia
| | - Kyle Bibby
- Department of Civil & Environmental Engineering & Earth Science, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, IN 46556, USA
| | - Aaron Bivins
- Department of Civil & Environmental Engineering & Earth Science, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, IN 46556, USA
| | - Linda L Blackall
- School of BioSciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Sílvia Bofill-Mas
- Laboratory of Virus Contaminants of Water and Food, Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Albert Bosch
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, University of Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain
| | - João Brandão
- Department of Environmental Health, National Institute of Health Dr. Ricardo Jorge, Lisboa, Portugal
| | - Phil M Choi
- Water Unit, Health Protection Branch, Prevention Division, Queensland Health, QLD, Australia; The University of Queensland, Queensland Alliance for Environmental Health Sciences, QLD, Australia
| | - Mark Ciesielski
- University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC, United States
| | - Erica Donner
- Future Industries Institute, University of South Australia, University Boulevard, Mawson Lakes, SA 5095, Australia
| | - Nishita D'Souza
- Department of Fisheries and Wildlife, Michigan State University, E. Lansing, MI, USA
| | - Andreas H Farnleitner
- Institute of Chemical, Environmental & Bioscience Engineering, Research Group Environmental Microbiology and Molecular Diagnostic, 166/5/3, Technische Universität Wien, Vienna, Austria; Research Division Water Quality and Health, Department Pharmacology, Physiology and Microbiology, Karl Landsteiner University of Health Sciences, Dr. Karl-Dorrek-Straβe 30, 3500 Krems an der Donau, Austria
| | - Daniel Gerrity
- Southern Nevada Water Authority, P.O. Box 99954, Las Vegas, NV 89193, USA
| | - Raul Gonzalez
- Hampton Roads Sanitation District, 1434 Air Rail Avenue, Virginia Beach, VA 23455, USA
| | - John F Griffith
- Southern California Coastal Water Research Project, Costa Mesa, CA 92626, USA
| | - Pradip Gyawali
- Institute of Environmental Science and Research Ltd (ESR), Porirua 5240, New Zealand
| | | | - Kerry A Hamilton
- School of Sustainable Engineering and the Built Environment and The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, AZ 85287, USA
| | | | - Valerie J Harwood
- Department of Integrative Biology, University of South Florida, Tampa, FL, USA
| | - Rehnuma Haque
- Environmental Interventions Unit, Icddr,b, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Greg Jackson
- Water Unit, Health Protection Branch, Prevention Division, Queensland Health, QLD, Australia
| | - Stuart J Khan
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, NSW 2052, Australia
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - Masaaki Kitajima
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
| | - Asja Korajkic
- United States Environmental Protection Agency, Office of Research and Development, 26W Martin Luther King Jr. Drive, Cincinnati, OH 45268, USA
| | - Giuseppina La Rosa
- Department of Environment and Health, Istituto Superiore di Sanità, Rome, Italy
| | - Blythe A Layton
- Department of Research & Innovation, Clean Water Services, Hillsboro, OR, USA
| | - Erin Lipp
- Environmental Health Sciences Department, University of Georgia, Athens, GA 30602, USA
| | - Sandra L McLellan
- School of Freshwater Sciences, University of Wisconsin-Milwaukee, WI, USA
| | - Brian McMinn
- United States Environmental Protection Agency, Office of Research and Development, 26W Martin Luther King Jr. Drive, Cincinnati, OH 45268, USA
| | - Gertjan Medema
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, the Netherlands
| | - Suzanne Metcalfe
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia
| | - Wim G Meijer
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Jochen F Mueller
- The University of Queensland, Queensland Alliance for Environmental Health Sciences, QLD, Australia
| | - Heather Murphy
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Coleen C Naughton
- University of California Merced, Department of Civil and Environmental Engineering, 5200 N. Lake Rd., Merced, CA 95343, USA
| | - Rachel T Noble
- University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC, United States
| | - Sudhi Payyappat
- Sydney Water, 1 Smith Street, Parramatta, NSW 2150, Australia
| | - Susan Petterson
- Water and Health Pty Ltd., 13 Lord St, North Sydney, NSW 2060, Australia; School of Medicine, Griffith University, Parklands Drive, Gold Coast, Australia
| | - Tarja Pitkänen
- Finnish Institute for Health and Welfare, Expert Microbiology Unit, P.O. Box 95, FI-70701 Kuopio, Finland; University of Helsinki, Faculty of Veterinary Medicine, Department of Food Hygiene and Environmental Health, P.O. Box 66, FI-00014, Finland
| | - Veronica B Rajal
- Facultad de Ingeniería and Instituto de Investigaciones para la Industria Química (INIQUI) - CONICET and Universidad Nacional de Salta, Av. Bolivia 5150, Salta, Argentina
| | - Brandon Reyneke
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - Fernando A Roman
- University of California Merced, Department of Civil and Environmental Engineering, 5200 N. Lake Rd., Merced, CA 95343, USA
| | - Joan B Rose
- Department of Fisheries and Wildlife, Michigan State University, E. Lansing, MI, USA
| | - Marta Rusiñol
- Institute of Environmental Assessment & Water Research (IDAEA), CSIC, Barcelona, Spain
| | - Michael J Sadowsky
- Biotechnology Institute and Department of Soil, Water, and Climate, University of Minnesota, St. Paul, MN, USA
| | - Laura Sala-Comorera
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Yin Xiang Setoh
- Environmental Health Institute, National Environment Agency, Singapore
| | - Samendra P Sherchan
- Department of Environmental Health Sciences, Tulane University, 1440 Canal Street, New Orleans, LA 70112, USA
| | - Kwanrawee Sirikanchana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok 10210, Thailand
| | - Wendy Smith
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia
| | - Joshua A Steele
- Southern California Coastal Water Research Project, Costa Mesa, CA 92626, USA
| | - Rosalie Sabburg
- CSIRO Agriculture and Food, Bioscience Precinct, St Lucia, QLD 4067, Australia
| | - Erin M Symonds
- College of Marine Science, University of South Florida, St. Petersburg, FL, USA
| | - Phong Thai
- The University of Queensland, Queensland Alliance for Environmental Health Sciences, QLD, Australia
| | - Kevin V Thomas
- The University of Queensland, Queensland Alliance for Environmental Health Sciences, QLD, Australia
| | - Josh Tynan
- The University of Queensland, Queensland Alliance for Environmental Health Sciences, QLD, Australia
| | - Simon Toze
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia
| | - Janelle Thompson
- Asian School of the Environment, Nanyang Technological University, Singapore 639798, Singapore; Singapore Centre for Environmental Life Sciences Engineering (SCELSE) Singapore 637551
| | | | | | - Daisuke Sano
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6-06, Aramaki, Aoba-Ku, Sendai, Miyagi 980-8597, Japan
| | - Stefan Wuertz
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE) Singapore 637551; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798
| | - Irene Xagoraraki
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Qian Zhang
- Biotechnology Institute and Department of Soil, Water, and Climate, University of Minnesota, St. Paul, MN, USA
| | | | - Orin C Shanks
- United States Environmental Protection Agency, Office of Research and Development, 26W Martin Luther King Jr. Drive, Cincinnati, OH 45268, USA
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9
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Goh SG, Liang L, Gin KYH. Assessment of Human Health Risks in Tropical Environmental Waters with Microbial Source Tracking Markers. WATER RESEARCH 2021; 207:117748. [PMID: 34837748 DOI: 10.1016/j.watres.2021.117748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Human specific microbial source tracking (MST) markers which are highly specific to human waste contamination offer the advantage of better association with human pathogens than traditional microbial indicators. However, the performance of these MST markers may vary across different geographical regions. The magnitude of MST markers also plays an important role in interpreting the health risks. This study aims to (i) validate the specificity and sensitivity of human markers for tropical urban catchments; (ii) identify the threshold concentrations of MST markers, i.e. human polyomaviruses (HPyVs), Bacteroides thetaiotaomicron (B. theta) and Methanobrevibacter smithii (M. smithii), that correspond to the acceptable gastrointestinal (GI) illness risks associated with swimming using the QMRA approach; and (iii) validate the threshold concentrations of MST markers using the surveillance data obtained from the tropical urban environment. Among the three MST markers, HPyVs showed the highest specificity (100%) to sewage samples, followed by M. smithii (97%) and B. theta (90%). All MST markers showed 100% sensitivity towards sewage contamination, with B. theta present in highest abundance in sewage, followed by HPyVs and M. smithii. This study demonstrates a risk-based framework to identify the threshold concentrations of MST markers associated with GI illness risks in environmental waters by considering two main influencing factors (i.e. decay and dilution factors). This study successfully validated the B. theta threshold concentration range (581 to 8073 GC/100 mL) with field data (370 to 6500 GC/100 mL) in estimating GI illness risks with an Enterococcus model. Field data showed that the MST markers at threshold concentrations were able to classify the safe level in more than 83% of the samples, according to GI illness risks from Enterococcus and adenovirus. The study also highlighted the lack of associations between MST markers and GI illness risks from norovirus. With comprehensive information on specificity, sensitivity and threshold concentrations of MST markers, increasing confidence can be placed on identifying human source contamination and evaluating the health risks posed in environmental waters in Singapore.
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Affiliation(s)
- S G Goh
- NUS Environmental Research Institute, National University of Singapore, T-Lab Building, #02-01, 5A Engineering Drive 1 117411, Singapore
| | - L Liang
- Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-03,1 Engineering Drive 2 117576, Singapore
| | - K Y H Gin
- NUS Environmental Research Institute, National University of Singapore, T-Lab Building, #02-01, 5A Engineering Drive 1 117411, Singapore; Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-03,1 Engineering Drive 2 117576, Singapore.
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10
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Gyawali P, Devane M, Scholes P, Hewitt J. Application of crAssphage, F-RNA phage and pepper mild mottle virus as indicators of human faecal and norovirus contamination in shellfish. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 783:146848. [PMID: 33865125 DOI: 10.1016/j.scitotenv.2021.146848] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 06/12/2023]
Abstract
Shellfish growing waters contaminated with inadequately treated human wastewater is a major source of norovirus in shellfish and poses a significant human health risk to consumers. Microbial source tracking (MST) markers have been widely used to identify the source (s) of faecal contamination in water but data are limited on their use for shellfish safety. This study evaluated the source specificity, sensitivity, occurrence and concentration of three viral MST markers i.e. cross-assembly phage (crAssphage), F-specific RNA bacteriophage genogroup II (F-RNA phage GII) and pepper mild mottle virus (PMMoV) using animal faeces (n = 119; 16 animal groups), influent wastewater (n = 12), effluent wastewater (n = 16) and shellfish (n = 33). CrAssphage, F-RNA phage GII and PMMoV had source specific values of 0.97, 0.99 and 0.91, respectively. The sensitivity of MST markers was confirmed by their 100% detection frequency in influent wastewaters. The frequency of detection in effluent wastewater ranged from 81.3% (F-RNA phage GII) to 100% (PMMoV). Concentration of F-RNA phage GII was one log10 (influent wastewater) and 2-3 log10 (effluent wastewater) lower than crAssphage and PMMoV, respectively. Despite lower prevalence of F-RNA phage GII in oysters and mussels compared to crAssphage and PMMoV, concentrations of the three MST markers were similar in mussels. As an indicator of norovirus contamination in shellfish, crAssphage and PMMoV had greater predictive sensitivity (100%; [95% CI; 81.5%-100%)]) and F-RNA phage GII had greater predictive specificity (93.3%; [95% CI; 68.1%-99.8%]). In contrast, crAssphage and F-RNA phage GII have similar accuracy for predicting norovirus in shellfish, however, PMMoV significantly overestimated its presence. Therefore, a combination of crAssphage and F-RNA phage GII analysis of shellfish could provide a robust estimation of the presence of human faecal and norovirus contamination.
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Affiliation(s)
- Pradip Gyawali
- Institute of Environmental Science and Research Ltd (ESR), Porirua 5240, New Zealand.
| | - Megan Devane
- Institute of Environmental Science and Research Ltd (ESR), Christchurch 8041, New Zealand
| | - Paula Scholes
- Institute of Environmental Science and Research Ltd (ESR), Christchurch 8041, New Zealand
| | - Joanne Hewitt
- Institute of Environmental Science and Research Ltd (ESR), Porirua 5240, New Zealand.
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11
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Derx J, Demeter K, Linke R, Cervero-Aragó S, Lindner G, Stalder G, Schijven J, Sommer R, Walochnik J, Kirschner AKT, Komma J, Blaschke AP, Farnleitner AH. Genetic Microbial Source Tracking Support QMRA Modeling for a Riverine Wetland Drinking Water Resource. Front Microbiol 2021; 12:668778. [PMID: 34335498 PMCID: PMC8317494 DOI: 10.3389/fmicb.2021.668778] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/18/2021] [Indexed: 11/30/2022] Open
Abstract
Riverine wetlands are important natural habitats and contain valuable drinking water resources. The transport of human- and animal-associated fecal pathogens into the surface water bodies poses potential risks to water safety. The aim of this study was to develop a new integrative modeling approach supported by microbial source tracking (MST) markers for quantifying the transport pathways of two important reference pathogens, Cryptosporidium and Giardia, from external (allochthonous) and internal (autochthonous) fecal sources in riverine wetlands considering safe drinking water production. The probabilistic-deterministic model QMRAcatch (v 1.1 python backwater) was modified and extended to account for short-time variations in flow and microbial transport at hourly time steps. As input to the model, we determined the discharge rates, volumes and inundated areas of the backwater channel based on 2-D hydrodynamic flow simulations. To test if we considered all relevant fecal pollution sources and transport pathways, we validated QMRAcatch using measured concentrations of human, ruminant, pig and bird associated MST markers as well as E. coli in a Danube wetland area from 2010 to 2015. For the model validation, we obtained MST marker decay rates in water from the literature, adjusted them within confidence limits, and simulated the MST marker concentrations in the backwater channel, resulting in mean absolute errors of < 0.7 log10 particles/L (Kruskal–Wallis p > 0.05). In the scenarios, we investigated (i) the impact of river discharges into the backwater channel (allochthonous sources), (ii) the resuspension of pathogens from animal fecal deposits in inundated areas, and (iii) the pathogen release from animal fecal deposits after rainfall (autochthonous sources). Autochthonous and allochthonous human and animal sources resulted in mean loads and concentrations of Cryptosporidium and Giardia (oo)cysts in the backwater channel of 3–13 × 109 particles/hour and 0.4–1.2 particles/L during floods and rainfall events, and in required pathogen treatment reductions to achieve safe drinking water of 5.0–6.2 log10. The integrative modeling approach supports the sustainable and proactive drinking water safety management of alluvial backwater areas.
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Affiliation(s)
- Julia Derx
- Institute of Hydraulic Engineering and Water Resources Management, Vienna, Austria
| | - Katalin Demeter
- Research Group Environmental Microbiology and Molecular Diagnostics E166/5/3, Institute of Chemical, Environmental and Bioscience Engineering, Vienna, Austria
| | - Rita Linke
- Research Group Environmental Microbiology and Molecular Diagnostics E166/5/3, Institute of Chemical, Environmental and Bioscience Engineering, Vienna, Austria
| | - Sílvia Cervero-Aragó
- Institute for Hygiene and Applied Immunology, Medical University of Vienna, Vienna, Austria
| | - Gerhard Lindner
- Institute of Hydraulic Engineering and Water Resources Management, Vienna, Austria
| | - Gabrielle Stalder
- Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Austria
| | - Jack Schijven
- Department of Statistics, Informatics and Modelling, National Institute for Public Health and the Environment (RIVM), Bilthoven, Netherlands.,Faculty of Geosciences, Department of Earth Sciences, Utrecht University, Utrecht, Netherlands
| | - Regina Sommer
- Institute for Hygiene and Applied Immunology, Medical University of Vienna, Vienna, Austria
| | - Julia Walochnik
- Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Alexander K T Kirschner
- Institute for Hygiene and Applied Immunology, Medical University of Vienna, Vienna, Austria.,Division Water Quality and Health, Department of Pharmacology, Physiology, and Microbiology, Karl Landsteiner University of Health Sciences, Krems an der Donau, Austria
| | - Jürgen Komma
- Institute of Hydraulic Engineering and Water Resources Management, Vienna, Austria
| | - Alfred P Blaschke
- Institute of Hydraulic Engineering and Water Resources Management, Vienna, Austria
| | - Andreas H Farnleitner
- Research Group Environmental Microbiology and Molecular Diagnostics E166/5/3, Institute of Chemical, Environmental and Bioscience Engineering, Vienna, Austria.,Division Water Quality and Health, Department of Pharmacology, Physiology, and Microbiology, Karl Landsteiner University of Health Sciences, Krems an der Donau, Austria
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12
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Liang H, Yu Z, Wang B, Ndayisenga F, Liu R, Zhang H, Wu G. Synergistic Application of Molecular Markers and Community-Based Microbial Source Tracking Methods for Identification of Fecal Pollution in River Water During Dry and Wet Seasons. Front Microbiol 2021; 12:660368. [PMID: 34194406 PMCID: PMC8236858 DOI: 10.3389/fmicb.2021.660368] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022] Open
Abstract
It is important to track fecal sources from humans and animals that negatively influence the water quality of rural rivers and human health. In this study, microbial source tracking (MST) methods using molecular markers and the community-based FEAST (fast expectation–maximization microbial source tracking) program were synergistically applied to distinguish the fecal contributions of multiple sources in a rural river located in Beijing, China. The performance of eight markers were evaluated using 133 fecal samples based on real-time quantitative (qPCR) technique. Among them, six markers, including universal (BacUni), human-associated (HF183-1 and BacH), swine-associated (Pig-2-Bac), ruminant-associated (Rum-2-Bac), and avian-associated (AV4143) markers, performed well in the study. A total of 96 water samples from the river and outfalls showed a coordinated composition of fecal pollution, which revealed that outfall water might be a potential input of the Fsq River. In the FEAST program, bacterial 16S rRNA genes of 58 fecal and 12 water samples were sequenced to build the “source” library and “sink,” respectively. The relative contribution (<4.01% of sequence reads) of each source (i.e., human, swine, bovine, or sheep) was calculated based on simultaneous screening of the operational taxonomic units (OTUs) of sources and sinks, which indicated that community-based MST methods could be promising tools for identifying fecal sources from a more comprehensive perspective. Results of the qPCR assays indicated that fecal contamination from human was dominant during dry weather and that fecal sources from swine and ruminant were more prevalent in samples during the wet season than in those during the dry season, which were consistent with the findings predicted by the FEAST program using a very small sample size. Information from the study could be valuable for the development of improved regulation policies to reduce the levels of fecal contamination in rural rivers.
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Affiliation(s)
- Hongxia Liang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Zhisheng Yu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China.,RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China
| | - Bobo Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Fabrice Ndayisenga
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Ruyin Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Hongxun Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Gang Wu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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13
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Rytkönen A, Tiwari A, Hokajärvi AM, Uusheimo S, Vepsäläinen A, Tulonen T, Pitkänen T. The Use of Ribosomal RNA as a Microbial Source Tracking Target Highlights the Assay Host-Specificity Requirement in Water Quality Assessments. Front Microbiol 2021; 12:673306. [PMID: 34149662 PMCID: PMC8206488 DOI: 10.3389/fmicb.2021.673306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/19/2021] [Indexed: 12/28/2022] Open
Abstract
For microbial source tracking (MST), the 16S ribosomal RNA genes (rDNA) of host-specific bacteria and mitochondrial DNA (mtDNA) of animal species, known to cause fecal contamination of water, have been commonly used as molecular targets. However, low levels of contamination might remain undetected by using these DNA-based qPCR assays. The high copy numbers of ribosomal RNA (rRNA) could offer a solution for such applications of MST. This study compared the performance of eight MST assays: GenBac3 (general Bacteroidales), HF183 (human), BacCan (dog), Rum-2-Bac (ruminant), Pig-2-Bac (swine), Gull4 (gull), GFD, and Av4143 (birds) between rRNA-based and rDNA-based approaches. Three mtDNA-based approaches were tested: DogND5, SheepCytB, and HorseCytB. A total of 151 animal fecal samples and eight municipal sewage samples from four regions of Finland were collected for the marker evaluation. The usability of these markers was tested by using a total of 95 surface water samples with an unknown pollution load. Overall, the performance (specificity, sensitivity, and accuracy) of mtDNA-based assays was excellent (95–100%), but these markers were very seldom detected from the tested surface water samples. The rRNA template increased the sensitivity of assays in comparison to the rDNA template. All rRNA-based assays (except Av4143) had more than 80% sensitivity. In contrast, only half (HF183, Rum-2-Bac, Pig-2-Bac, and Gull4) of rDNA-based assays reached this value. For markers targeted to bird feces, the use of the rRNA-based assay increased or at least did not change the performance. Regarding specificity, all the assays had >95% specificity with a DNA template, except the BacCan assay (71%). While using the RNA template for the assays, HF183 and BacCan exhibited only a low level of specificity (54 and 55%, respectively). Further, the HF183 assay amplified from multiple non-targeted animal fecal samples with the RNA template and the marker showed cross-amplification with the DNA template as well. This study recommends using the rRNA-based approach for MST assays targeting bird fecal contamination. In the case of mammal-specific MST assays, the use of the rRNA template increases the sensitivity but may reduce the specificity and accuracy of the assay. The finding of increased sensitivity calls for a further need to develop better rRNA-based approaches to reach the required assay performance.
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Affiliation(s)
- Annastiina Rytkönen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Ananda Tiwari
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Anna-Maria Hokajärvi
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Sari Uusheimo
- Lammi Biological Station, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Asko Vepsäläinen
- Environmental Health Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Tiina Tulonen
- Lammi Biological Station, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Tarja Pitkänen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland.,Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
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14
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Chen H, Liu C, Li Y, Teng Y. Integrating Metagenomic and Bayesian Analyses to Evaluate the Performance and Confidence of CrAssphage as an Indicator for Tracking Human Sewage Contamination in China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4992-5000. [PMID: 33715349 DOI: 10.1021/acs.est.1c00071] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Recently, crAssphage has been proposed as a human-specific marker for tracking fecal contamination. However, its performance has always been validated in a limited number of host samples, which may obscure our understanding of its utility. Furthermore, few studies have quantified confidence of fecal contamination when using crAssphage. Here, we evaluate the performance and confidence of crAssphage by analyzing a large panel of metagenomic data sets combined with Bayesian analyses. Results demonstrate that crAssphage exhibits superior performance with high host sensitivity and specificity, indicating its suitability for tracking human fecal sources. With the marker, a high confidence (>90%) can be obtained and particularly, multiple samples with positive results provide a near certainty of confidence. The application of crAssphage in the sediments of three Chinese urban rivers shows a high confidence of >97% of human fecal contamination, suggesting the serious challenge of sewage pollution in these environments. Additionally, significant correlation is observed between crAssphage and antibiotic resistance genes (ARGs), expanding the utilization of crAssphage for pollution management of ARGs. This study highlights the benefit of using metagenomic-based analysis for evaluating the performance and confidence of microbial source tracking markers in the coming era of big data with increasing resources in available metagenomic data.
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Affiliation(s)
- Haiyang Chen
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education; College of Water Sciences, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing 100875, P. R. China
| | - Chang Liu
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education; College of Water Sciences, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing 100875, P. R. China
| | - Yuezhao Li
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education; College of Water Sciences, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing 100875, P. R. China
| | - Yanguo Teng
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education; College of Water Sciences, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing 100875, P. R. China
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15
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Joseph N, Lucas J, Viswanath N, Findlay R, Sprinkle J, Strickland MS, Winford E, Kolok AS. Investigation of relationships between fecal contamination, cattle grazing, human recreation, and microbial source tracking markers in a mixed-land-use rangeland watershed. WATER RESEARCH 2021; 194:116921. [PMID: 33609910 DOI: 10.1016/j.watres.2021.116921] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
The United States National Forests are mixed-use lands that support human recreation and cattle grazing. Overuse by humans or cattle, however, can lead to the fecal contamination of local waterways. Until recently, the source of these contaminants was a subject of conjecture; however, microbial source tracking tools have become widely used and are proving to be a valid methodology to identify the contamination source. This study aims to analyze and model the quantity and sources of fecal contamination in the Mink Creek watershed in southeastern Idaho. The U.S. Forest Service Caribou-Targhee National Forest (USFS) manages this watershed. Previous research has indicated that some localities within the watershed exceed US EPA standards for coliform bacteria. In 2019, water samples were collected before livestock began grazing and throughout the spring, summer, and fall after livestock grazing had ended. Fourteen sites were sampled seven times during the field season, allowing the water to be analyzed for total coliforms and E. coli bacteria. Microbial source tracking techniques using Bacteroides bacteria, which are known to live in specific digestive tracks, were used to identify the source of E. coli at each sampling location. The analysis indicated that E. coli counts exceeded state regulatory limits 35% of the time. These exceedances were associated with DNA source tracking markers for humans (58.8%), cattle (5.9%), or both cattle and humans (5.9%). Unknown sources were responsible for the Bacteroides bacteria 29.4% of the time. A statistical model was developed to estimate E. coli using the datasets of microbial source tracking measures, the presence or absence of humans, cattle, the proximity of the sampling date to a holiday, and other seasonal factors. The resulting model showed good performance indices at all the 14 sites based on a K-fold cross-validation scheme (R2 = 0.83 and NSE = 0.69). The results demonstrated that E. coli exceedances have a close association with human recreation and unknown sources and negatively influenced by dissolved oxygen.
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Affiliation(s)
- Naveen Joseph
- Idaho Water Resources Research Institute, University of Idaho, Moscow, ID, USA
| | - Jane Lucas
- Department of Soil and Water Systems, University of Idaho, Moscow, ID, USA
| | - Nikhil Viswanath
- Idaho Water Resources Research Institute, University of Idaho, Moscow, ID, USA
| | - Reed Findlay
- University of Idaho Extension - Eastern District, University of Idaho, Pocatello, ID, USA
| | - Jim Sprinkle
- Nancy M. Cummings Research, Extension and Education Center, University of Idaho, Carmen, ID, USA
| | | | - Eric Winford
- Rangeland Center, University of Idaho, Boise, ID, USA
| | - Alan S Kolok
- Idaho Water Resources Research Institute, University of Idaho, Moscow, ID, USA.
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16
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Sangkaew W, Kongprajug A, Chyerochana N, Ahmed W, Rattanakul S, Denpetkul T, Mongkolsuk S, Sirikanchana K. Performance of viral and bacterial genetic markers for sewage pollution tracking in tropical Thailand. WATER RESEARCH 2021; 190:116706. [PMID: 33310444 DOI: 10.1016/j.watres.2020.116706] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
Identifying sewage contamination via microbial source tracking (MST) marker genes has proven useful for effective water quality management worldwide; however, performance evaluations for these marker genes in tropical areas are limited. Therefore, this research evaluated four human-associated MST marker genes (human polyomaviruses (JC and BK viruses [HPyVs]), bacteriophage crAssphage (CPQ_056), Lachnospiraceae Lachno3, and Bacteroides BacV6-21) for tracking sewage pollution in aquatic environments of Thailand. The viral marker genes, HPyV and crAssphage were highly sensitive and specific to sewage from onsite wastewater treatment plants (OWTPs; n = 19), with no cross-detection in 120 composite swine, cattle, chicken, duck, goat, sheep, and buffalo fecal samples. The bacterial marker genes, Lachno3 and BacV6-21, demonstrated high sensitivity but moderate specificity; however, using both markers could improve specificity to >0.80 (max value of 1.00). The most abundant markers in OWTP samples were Lachno3 and BacV6-21 (5.42-8.02 and nondetect-8.05 log10 copies/100 mL), crAssphage (5.28-7.38 log10 copies/100 mL), and HPyVs (3.66-6.53 log10 copies/100 mL), respectively. Due to their increased specificity, the abundance of viral markers were further investigated in environmental waters, in which HPyVs showed greater levels (up to 4.33 log10 copies/100 mL) and greater detection rates (92.7%) in two coastal beaches (n = 41) than crAssphage (up to 3.51 log10 copies/100 mL and 56.1%). HPyVs were also found at slightly lower levels (up to 5.10 log10 copies/100 mL), but at higher detection rates (92.6%), in a freshwater canal (n = 27) than crAssphage (up to 5.21 log10 copies/100 mL and 88.9%). HPyVs and crAssphage marker genes were identified as highly sensitive and specific for tracking sewage pollution in aquatic environments of Thailand. This study underlines the importance of characterizing and validating MST markers in host groups and environmental waters before including them in a water quality management toolbox.
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Affiliation(s)
- Watsawan Sangkaew
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok, 10210, Thailand
| | - Akechai Kongprajug
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok, 10210, Thailand
| | - Natcha Chyerochana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok, 10210, Thailand
| | - Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia
| | - Surapong Rattanakul
- Department of Environmental Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi, 126 Pracha Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140, Thailand
| | - Thammanitchpol Denpetkul
- Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand
| | - Skorn Mongkolsuk
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok, 10210, Thailand; Center of Excellence on Environmental Health and Toxicology, CHE, Ministry of Education, 272 Rama 6 Road, Ratchathevi, Bangkok, 10400, Thailand
| | - Kwanrawee Sirikanchana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, 54 Kampangpetch 6 Road, Laksi, Bangkok, 10210, Thailand; Center of Excellence on Environmental Health and Toxicology, CHE, Ministry of Education, 272 Rama 6 Road, Ratchathevi, Bangkok, 10400, Thailand.
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Hart JD, Blackwood AD, Noble RT. Examining coastal dynamics and recreational water quality by quantifying multiple sewage specific markers in a North Carolina estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 747:141124. [PMID: 32795790 DOI: 10.1016/j.scitotenv.2020.141124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/16/2020] [Accepted: 07/18/2020] [Indexed: 06/11/2023]
Abstract
Fecal contamination is observed downstream of municipal separate storm sewer systems in coastal North Carolina. While it is well accepted that wet weather contributes to this phenomenon, less is understood about the contribution of the complex hydrology in this low-lying coastal plain. A quantitative microbial assessment was conducted in Beaufort, North Carolina to identify trends and potential sources of fecal contamination in stormwater receiving waters. Fecal indicator concentrations were significantly higher in receiving water downstream of a tidally submerged outfall compared to an outfall that was permanently submerged (p < 0.001), though tidal height was not predictive of human-specific microbial source tracking (MST) marker concentrations at the tidally submerged site. Short-term rainfall (i.e. <12 h) was predictive of E. coli, Enterococcus spp., and human-specific MST marker concentrations (Fecal Bacteroides, BacHum, and HF183) in receiving waters. The strong correlation between 12-hr antecedent rainfall and Enterococcus spp. (r = 0.57, p < 0.001, n = 92) suggests a predictive model could be developed based on rainfall to communicate risk for bathers. Additional molecular marker data indicates that the delivery of fecal sources is complex and highly variable, likely due to the influence of tidal influx (saltwater intrusion from the estuary) into the low-lying stormwater pipes. In particular, elevated MST marker concentrations (up to 2.56 × 104 gene copies HF183/mL) were observed in standing water near surcharging street storm drain. These data are being used to establish a baseline for stormwater dynamics prior to dramatic rainfall in 2018 and to characterize the interaction between complex stormwater dynamics and water quality impairment in coastal NC.
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Affiliation(s)
- Justin D Hart
- University of North Carolina Institute of Marine Sciences, Morehead City, NC, United States of America; Department of Environmental Sciences and Engineering, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC, United States of America
| | - A Denene Blackwood
- University of North Carolina Institute of Marine Sciences, Morehead City, NC, United States of America
| | - Rachel T Noble
- University of North Carolina Institute of Marine Sciences, Morehead City, NC, United States of America; Department of Environmental Sciences and Engineering, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC, United States of America.
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18
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Zeki S, Aslan A, Burak S, Rose JB. Occurrence of a human-associated microbial source tracking marker and its relationship with faecal indicator bacteria in an urban estuary. Lett Appl Microbiol 2020; 72:167-177. [PMID: 33025621 DOI: 10.1111/lam.13405] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/20/2020] [Accepted: 09/29/2020] [Indexed: 12/22/2022]
Abstract
One of the main impacts of urban sprawl in rapidly growing countries has been contamination of coastal environments by waterborne pathogens, posing a critical risk to ecosystem and human health. Microbial source tracking (MST) has been a robust tool to identify the origin of these pathogens globally. This study compared the occurrence of a human-associated Bacteroides marker (BT-α) with faecal indicator bacteria (FIB) in an urban estuary (Golden Horn, Istanbul, Turkey). Faecal coliform (culture method), enterococci (both culture and qPCR method) concentrations and physicochemical variables were compared with the BT-α concentrations in monthly collected samples for a year (n = 108). Enterococci concentrations detected by culture and qPCR were positively correlated (r = 0·86, P < 0·01) suggesting that qPCR can be an alternative method for monitoring. BT-α marker was positive for 30% of the samples and positively correlated with enterococci (r = 0·61 and r = 0·64 for culture and qPCR methods respectively, P < 0·01). Rainfall had a moderate positive correlation with all faecal/MST indicators suggesting combined sewer overflows also severely impacted estuarine water quality. The high FIB and BT-α concentrations at upper estuary suggested that faecal pollution mainly originated from the peri-urban settlements around two creeks entering the estuary.
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Affiliation(s)
- S Zeki
- Department of Marine Environment, Institute of Marine Sciences and Management, Istanbul University, Istanbul, Turkey
| | - A Aslan
- Department of Biostatistics, Epidemiology and Environmental Health Sciences, Jiann-Ping Hsu College of Public Health, Georgia Southern University, Statesboro, GA, USA
| | - S Burak
- Department of Marine Environment, Institute of Marine Sciences and Management, Istanbul University, Istanbul, Turkey
| | - J B Rose
- Department of Fisheries and Wildlife, College of Agriculture and Natural Resources, Michigan State University, East Lansing, MI, USA
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Mattioli MC, Benedict KM, Murphy J, Kahler A, Kline KE, Longenberger A, Mitchell PK, Watkins S, Berger P, Shanks OC, Barrett CE, Barclay L, Hall AJ, Hill V, Weltman A. Identifying septic pollution exposure routes during a waterborne norovirus outbreak - A new application for human-associated microbial source tracking qPCR. J Microbiol Methods 2020; 180:106091. [PMID: 33137355 DOI: 10.1016/j.mimet.2020.106091] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/13/2020] [Accepted: 10/27/2020] [Indexed: 11/18/2022]
Abstract
In June 2017, the Pennsylvania Department of Health (PADOH) was notified of multiple norovirus outbreaks associated with 179 ill individuals who attended separate events held at an outdoor venue and campground over a month period. Epidemiologic investigations were unable to identify a single exposure route and therefore unable to determine whether there was a persistent contamination source to target for exposure mitigation. Norovirus was detected in a fresh recreational water designated swimming area and a drinking water well. A hydrogeological site evaluation suggested a nearby septic leach field as a potential contamination source via ground water infiltration. Geological characterization revealed a steep dip of the bedrock beneath the septic leach field toward the well, providing a viral transport pathway in a geologic medium not previously documented as high risk for viral ground water contamination. The human-associated microbial source tracking (MST) genetic marker, HF183, was used as a microbial tracer to demonstrate the hydrogeological connection between the malfunctioning septic system, drinking water well, and recreational water area. Based on environmental investigation findings, venue management and local public health officials implemented a series of outbreak prevention strategies including discontinuing the use of the contaminated well, issuing a permit for a new drinking water well, increasing portable toilet and handwashing station availability, and promoting proper hand hygiene. Despite the outbreaks at the venue and evidence of ground water contamination impacting nearby recreational water and the drinking water well, no new norovirus cases were reported during a large event one week after implementing prevention practices. This investigation highlights a new application for human-associated MST methods to trace hydrological connections between multiple fecal pollutant exposure routes in an outbreak scenario. In turn, pollutant source information can be used to develop effective intervention practices to mitigate exposure and prevent future outbreaks associated with human fecal contaminated waters.
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Affiliation(s)
- Mia C Mattioli
- 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, USA.
| | - Katharine M Benedict
- 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, USA
| | - Jennifer Murphy
- 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, USA
| | - Amy Kahler
- 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, USA
| | - Kelly E Kline
- Pennsylvania Department of Health, Division of Infectious Disease Epidemiology, USA
| | - Allison Longenberger
- Pennsylvania Department of Health, Division of Infectious Disease Epidemiology, USA
| | - Patrick K Mitchell
- Pennsylvania Department of Health, Division of Infectious Disease Epidemiology, USA; Epidemic Intelligence Service, Division of Scientific Education and Professional Development, Center for Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Sharon Watkins
- Pennsylvania Department of Health, Division of Infectious Disease Epidemiology, USA
| | - Philip Berger
- U.S. Environmental Protection Agency, Office of Ground Water and Drinking Water, Washington, DC, USA
| | - Orin C Shanks
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA
| | - Catherine E Barrett
- 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, USA
| | - Leslie Barclay
- Viral Gastroenteritis Branch, Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, USA
| | - Aron J Hall
- Viral Gastroenteritis Branch, Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, USA
| | - Vincent Hill
- 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, USA
| | - Andre Weltman
- Pennsylvania Department of Health, Division of Infectious Disease Epidemiology, USA
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20
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Hinojosa J, Green J, Estrada F, Herrera J, Mata T, Phan D, Pasha ABMT, Matta A, Johnson D, Kapoor V. Determining the primary sources of fecal pollution using microbial source tracking assays combined with land-use information in the Edwards Aquifer. WATER RESEARCH 2020; 184:116211. [PMID: 32721766 DOI: 10.1016/j.watres.2020.116211] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 07/18/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
The Edwards Aquifer serves as a primary source of drinking water to more than 2 million people in south-central Texas, and as a karst aquifer, is vulnerable to human and animal fecal contamination which poses a serious risk to human and environmental health. A one-year study (Jan 2018 - Feb 2019) was conducted to determine the primary sources of fecal pollution along the Balcones and Leon Creek within the Edwards Aquifer recharge and contributing zones using general (E. coli, enterococci, and universal Bacteriodales) and host-associated (human-, dog-, cow- and chicken/duck-associated Bacteriodales) microbial source tracking (MST) assays. Additionally, sites were classified based on surrounding land use as a potential source predictor and marker levels were correlated with rain events and water quality parameters. Levels for the three general indicators were highest and exhibited similar trends across the sampling sites, suggesting that the sole use of these markers is not sufficient for specific fecal source identification. Among the host-associated markers, highest concentrations were observed for the dog marker (BacCan) in the Leon Creek area and the cow marker (BacCow) in the Balcones Creek area. Additionally, Chicken/Duck-Bac, BacCan and BacCow all exhibited higher concentrations during the spring season and the end of fall/early winter. Relatively lower concentrations were observed for the human-associated markers (HF183 and BacHum), however, levels were higher in the Leon Creek area and highest following rainfall events. Additionally, relatively higher levels in HF183 and BacHum were observed at sites having greater human population and septic tank density and may be attributed to leaks or breaks in these infrastructures. This study is the first to examine and compare fecal contamination at rural and urban areas in the recharge and contributing zones of the Edwards Aquifer using a molecular MST approach targeting Bacteroidales 16S rRNA gene-based assays. The Bacteroidales marker assays, when combined with land use and weather information, can allow for a better understanding of the sources and fluxes of fecal contamination, which can help devise effective mitigation measures to protect water quality.
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Affiliation(s)
- Jessica Hinojosa
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Jemima Green
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Fabiola Estrada
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Jonathan Herrera
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Troy Mata
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Duc Phan
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - A B M Tanvir Pasha
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Akanksha Matta
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Drew Johnson
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Vikram Kapoor
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA.
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Teixeira P, Dias D, Costa S, Brown B, Silva S, Valério E. Bacteroides spp. and traditional fecal indicator bacteria in water quality assessment - An integrated approach for hydric resources management in urban centers. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 271:110989. [PMID: 32579514 DOI: 10.1016/j.jenvman.2020.110989] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/28/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
As part of a sustainable water resources management, the Lisbon municipality identified groundwater and treated wastewater use increase as two opportunities for better and sustainable water use, with natural safeguard for public health as a priority. In this context, the aim of our research was to assess the suitability of the human-associated marker gene Bacteroides HF183 and the cattle feces-associated CowM2, in routine water quality monitoring as indicators for water use and reuse, providing a tool to more accurately assess public health risks. To this intent, Real-Time quantitative PCR was used for detection of human-associated marker gene Bacteroides HF183 and the bovine-associated CowM2, in a total of 67 samples - groundwater and wastewater at three different treatment stages of a Waste Water Treatment Plant, in Lisbon. HF183 marker gene was detected in treated and untreated wastewater samples, with significant concentration reductions from untreated (6,07 E+07 copies/mL) to secondary treated effluent (1,86 E+05 copies/mL) and a further decrease in tertiary treatment (5,74 E+04 copies/mL). In groundwater samples, this marker was also detected in concentrations ranging from 2,63 E+02 copies/mL to 2,24 E+03 copies/mL. CowM2 marker gene on the other hand was only detected in wastewater samples, with concentrations ranging from 2,47 E+02 copies/mL to 1,17 E+04 copies/mL. Our research indicates that the use of Bacteroides spp. in association with traditional fecal indicator bacteria (FIB) is advantageous for water managing entities in urban settings, such as Lisbon, were drainage system failures may occur. An integrated approach thus provides crucial and more adequate information towards mitigation and correction measures when fecal contamination is detected in environmental waters.
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Affiliation(s)
- Pedro Teixeira
- Câmara Municipal de Lisboa, Direcção Municipal Do Ambiente, Estrutura Verde, Clima e Energia, Laboratório de Bromatologia e Águas, Avenida Cidade Do Porto S/N, 1700-111, Lisboa, Portugal; Faculdade de Ciências da Universidade de Lisboa, Centro de Estudos Do Ambiente e Do Mar (CESAM Lisboa), Campo Grande, 1749-016, Lisboa, Portugal; Departamento de Saúde Ambiental, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisboa, Portugal.
| | - Deodália Dias
- Faculdade de Ciências da Universidade de Lisboa, Centro de Estudos Do Ambiente e Do Mar (CESAM Lisboa), Campo Grande, 1749-016, Lisboa, Portugal
| | - Sílvia Costa
- Câmara Municipal de Lisboa, Direcção Municipal Do Ambiente, Estrutura Verde, Clima e Energia, Laboratório de Bromatologia e Águas, Avenida Cidade Do Porto S/N, 1700-111, Lisboa, Portugal
| | - Bárbara Brown
- Câmara Municipal de Lisboa, Direcção Municipal Do Ambiente, Estrutura Verde, Clima e Energia, Laboratório de Bromatologia e Águas, Avenida Cidade Do Porto S/N, 1700-111, Lisboa, Portugal
| | - Susana Silva
- Departamento de Epidemiologia, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisboa, Portugal
| | - Elisabete Valério
- Departamento de Saúde Ambiental, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisboa, Portugal
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Relationship between Rainfall, Fecal Pollution, Antimicrobial Resistance, and Microbial Diversity in an Urbanized Subtropical Bay. Appl Environ Microbiol 2020; 86:AEM.01229-20. [PMID: 32709726 PMCID: PMC7499047 DOI: 10.1128/aem.01229-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022] Open
Abstract
The presence of human enteric pathogens, stemming from fecal pollution, is a serious environmental and public health concern in recreational waters. Accurate assessments of fecal pollution are therefore needed to properly assess exposure risks and guide water quality policies and practices. In this study, the absence of a direct correlation between enterococci and source-specific human and animal markers disputes the utility of enterococci as an indicator of fecal pollution in urbanized subtropical bays. Moreover, the inverse correlation between enterococci and the human-specific marker HF183 indicates that recreational beach advisories, triggered by elevated enterococcus concentrations, are a misleading practice. This study clearly demonstrates that a multiparameter approach that includes the quantitation of host-specific markers, as well as analyses of microbial diversity, is a more effective means of assessing water quality in urbanized subtropical bays. Urbanized bays are vulnerable to fecal bacterial pollution, and the extent of this pollution, in marine recreational waters, is commonly assessed by quantifying enterococcus concentrations. Recent reports have questioned the utility of enterococci as an indicator of fecal bacterial pollution in subtropical bays impaired by non-point source pollution, and enterococcus data alone cannot identify fecal bacterial sources (i.e., hosts). The purpose of this study was to assess relationships between rainfall, fecal bacterial pollution, antimicrobial resistance, and microbial diversity in an urbanized subtropical bay. Thus, a comprehensive bacterial source tracking (BST) study was conducted using a combination of traditional and modern BST methods. Findings show that rainfall was directly correlated with elevated enterococcus concentrations, including the increased prevalence of Enterococcus faecium, although it was not correlated with an increase in the prevalence of antimicrobial-resistant strains. Rainfall was also correlated with decreased microbial diversity. In contrast, neither rainfall nor enterococcus concentrations were directly correlated with the concentrations of three omnipresent host-associated fecal markers (i.e., human, canine, and gull). Notably, the human fecal marker (HF183) was inversely correlated with enterococcus concentrations, signifying that traditional enterococcus data alone are not an accurate proxy for human fecal waste in urbanized subtropical bays. IMPORTANCE The presence of human enteric pathogens, stemming from fecal pollution, is a serious environmental and public health concern in recreational waters. Accurate assessments of fecal pollution are therefore needed to properly assess exposure risks and guide water quality policies and practices. In this study, the absence of a direct correlation between enterococci and source-specific human and animal markers disputes the utility of enterococci as an indicator of fecal pollution in urbanized subtropical bays. Moreover, the inverse correlation between enterococci and the human-specific marker HF183 indicates that recreational beach advisories, triggered by elevated enterococcus concentrations, are a misleading practice. This study clearly demonstrates that a multiparameter approach that includes the quantitation of host-specific markers, as well as analyses of microbial diversity, is a more effective means of assessing water quality in urbanized subtropical bays.
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Zhu K, Suttner B, Pickering A, Konstantinidis KT, Brown J. A novel droplet digital PCR human mtDNA assay for fecal source tracking. WATER RESEARCH 2020; 183:116085. [PMID: 32750535 PMCID: PMC7495096 DOI: 10.1016/j.watres.2020.116085] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 05/22/2023]
Abstract
Human mitochondrial DNA provides a promising target for fecal source tracking because it is unique and intrinsic to humans. We developed a TaqMan chemistry assay, hCYTB484, targeting the cytochrome b gene of the human mitochondrial genome on a droplet digital PCR (ddPCR) platform and compared the performance of hCYTB484 with the HF183/BacR287 assay, a widely used assay targeting human-associated Bacteroides. For both assays, we defined the analytical limit of detection and analytical lower limit of quantification using frequency of detection and imprecision goals, respectively. We then established these analytical limits using empirical ddPCR data, presenting a novel approach to determining the analytical lower limit of quantification. We evaluated assay sensitivity using individual human feces from US, Bangladesh, and Mozambique and evaluated assay specificity using cow, pig, chicken, and goat samples collected from the US. To compare assay performance across a range of thresholds, we utilized receiver operating characteristic curves. The hCYTB484 marker was detected and quantifiable in 100% of the human feces from the 3 geographical distant regions whereas the HF183/BacR287 marker was detectable and quantifiable in 51% and 31% (respectively) of human feces samples. The hCYTB484 marker also was more specific (97%), having fewer detections in pig, chicken, and goat samples than the HF183/BacR287 marker (80%). The higher performance of the hCYTB484 marker in individual feces from geographically distant regions is desirable in the detection of fecal pollution from sources to which fewer individuals contribute, such as the non-sewered forms of sanitation (e.g. pit latrines and septic tanks) that serve most of Earth's population and carry the highest risk of exposure to fecal-oral pathogens.
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Affiliation(s)
- Kevin Zhu
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Brittany Suttner
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Amy Pickering
- Civil and Environmental Engineering, Tufts University, Medford, MA, USA
| | | | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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Kinzelman J, Byappanahalli MN, Nevers MB, Shively D, Kurdas S, Nakatsu C. Utilization of multiple microbial tools to evaluate efficacy of restoration strategies to improve recreational water quality at a Lake Michigan Beach (Racine, WI). J Microbiol Methods 2020; 178:106049. [PMID: 32891633 DOI: 10.1016/j.mimet.2020.106049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/05/2020] [Accepted: 08/14/2020] [Indexed: 12/31/2022]
Abstract
Hydro-meteorological conditions facilitate transport of fecal indicator bacteria (FIB) to the nearshore environment, affecting recreational water quality. North Beach (Racine, Wisconsin, United States), is an exemplar public beach site along Lake Michigan, where precipitation-mediated surface runoff, wave encroachment, stormwater and tributary outflow were demonstrated to contribute to beach advisories. Multiple restoration actions, including installation of a stormwater retention wetland, were successfully deployed to improve recreational water quality. Implementation of molecular methods (e.g. human microbial source tracking markers and Escherichia coli (E. coli) qPCR) assisted in identifying potential pollution sources and improving public health response time. However, periodic water quality failures still occur. As local beach managers reassess restoration measures in response to climatic changes, use of expanded microbial methods (including bacterial community profiling) may contribute to a better understanding of these dynamic environments. In this 2-year study (2015 and 2019), nearshore/offshore Lake Michigan, stormwater, and tributary samples were collected to determine if, 1) the constructed wetland (~50 m from the shoreline) continued to provide stormwater separation/retention and 2) mixing between onshore sources, Root River and Lake Michigan, was increasing due to rising precipitation/lake levels. Monthly rainfall totals were 1.5× higher in 2019 than 2015, coinciding with a 0.63 m lake-level rise. The prevalence of more intense, onshore winds also increased, facilitating interaction between potential reservoirs of FIB with nearshore water through wind driven waves and lake intrusion, e.g. beach sands and the adjacent Root River. While a strong relationship existed between wet weather wetland and North Beach nearshore E. coli concentrations (all sites), bacterial communities were strikingly different. Conversely, bacterial community overlap existed between the Root River mouth and nearshore/offshore sites. These results suggest the constructed wetland can accommodate the climate-related changes observed in this study. Future restoration activities could be directed towards upstream tributary sources in order to minimize microbial contaminants entering Lake Michigan.
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Affiliation(s)
- Julie Kinzelman
- City of Racine, Public Health Department Laboratory, 730 Washington Avenue, Racine, WI 53403, United States of America.
| | - M N Byappanahalli
- U.S. Geological Survey, Great Lakes Science Center, Lake Michigan Ecological Research Station, 1574 N 300 E, Chesterton, IN 46304, United States of America
| | - M B Nevers
- U.S. Geological Survey, Great Lakes Science Center, Lake Michigan Ecological Research Station, 1574 N 300 E, Chesterton, IN 46304, United States of America
| | - D Shively
- U.S. Geological Survey, Great Lakes Science Center, Lake Michigan Ecological Research Station, 1574 N 300 E, Chesterton, IN 46304, United States of America
| | - S Kurdas
- City of Racine, Public Health Department Laboratory, 730 Washington Avenue, Racine, WI 53403, United States of America
| | - C Nakatsu
- Purdue University, Department of Agronomy, 915 West State Street, West Lafayette, IN 47907, United States of America
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Kongprajug A, Chyerochana N, Mongkolsuk S, Sirikanchana K. Effect of Quantitative Polymerase Chain Reaction Data Analysis Using Sample Amplification Efficiency on Microbial Source Tracking Assay Performance and Source Attribution. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:8232-8244. [PMID: 32484662 DOI: 10.1021/acs.est.0c01559] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The widely used microbial source tracking (MST) technique, quantitative polymerase chain reaction (qPCR), quantifies host-specific gene abundance in polluted water to identify and prioritize contamination sources. This study characterized the effects of a qPCR data analysis using the sample PCR efficiencies (the LinRegPCR model) on gene abundance and compared them with the standard curve-based method (the mixed model). Five qPCR assays were evaluated: the universal GenBac3, human-specific HF183/BFDrev and CPQ_056, swine-specific Pig-2-Bac, and cattle-specific Bac3qPCR assays. The LinRegPCR model increased the low-copy amplification, especially in the HF183/BFDrev assay, thus lowering the specificity to 0.34. Up to 1.41 log10 copies/g and 0.41 log10 copies/100 mL differences were observed for composite fecal and sewage samples (n = 147) by the LinRegPCR approach, corresponding to an 18.2% increase and 6.4% decrease, respectively. Freshwater samples (n = 48) demonstrated a maximum of 1.95 log10 copies/100 mL difference between the two models. Identical attributing sources by both models were shown in 54.55% of environmental samples; meanwhile, the LinRegPCR approach improved the inability to identify sources by the mixed model in 29.55% of the samples. This study emphasizes the need for a standardized data analysis protocol for qPCR MST assays for interlaboratory consistency and comparability.
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Affiliation(s)
- Akechai Kongprajug
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
| | - Natcha Chyerochana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
| | - Skorn Mongkolsuk
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), Ministry of Education, Bangkok 10400, Thailand
| | - Kwanrawee Sirikanchana
- Research Laboratory of Biotechnology, Chulabhorn Research Institute, Lak Si, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), Ministry of Education, Bangkok 10400, Thailand
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26
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Mushi D. Bacteriological quality of marine recreational water in a tropical environment reflects coastal residential patterns. SCIENTIFIC AFRICAN 2020. [DOI: 10.1016/j.sciaf.2020.e00326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Zhang Y, Wu R, Lin K, Wang Y, Lu J. Performance of host-associated genetic markers for microbial source tracking in China. WATER RESEARCH 2020; 175:115670. [PMID: 32171096 DOI: 10.1016/j.watres.2020.115670] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 06/10/2023]
Abstract
Numerous genetic markers have been developed to establish microbial source tracking (MST) assays in the last decade. However, the selection of suitable markers is challenging due to a lack of understanding of fundamental factors such as sensitivity, specificity, and concentration in target/nontarget hosts, especially in East Asia. In this study, a total of 506 faecal samples comprised of human and 12 nonhuman hosts were collected from 28 cities across China and tested for marker performance characteristics. We firstly tested 40 host-associated markers based on a binary (presence/absence) criterion. Here, 15 markers (7 human-associated, 4 pig-associated, 3 ruminant-associated, and 1 poultry-associated) showed potential applicability in our study area. The selected 15 markers were then tested using qualitative and quantitative methods to characterise their performance. Overall, Bacteroidales markers presented higher sensitivity and concentrations in target samples compared to other bacterial or viral markers, but their specificity was low. Among nontarget samples, pets accounted for 43.7% and 35.7% of cross-reactivity with human-associated and poultry-associated markers, respectively. Noncommon animals, including horse and donkey, contributed 61.3% of cross-reactivity with ruminant-associated markers. When considering the quantitative distribution of markers, their concentration in nontarget samples were 1-3 orders of magnitude lower than in target samples. Moreover, a novel classification method was proposed to classify the nontarget hosts into four groups spanning "no cross-reactivity", "weak cross-reactivity", "moderate cross-reactivity", and "strong cross-reactivity" animal hosts. There were 77.9% nontarget samples identified as no cross-reactivity and weak cross-reactivity hosts, suggesting that these nontarget hosts produce little interference for corresponding markers. Our findings elucidate the performance of host-associated markers around China in a qualitative and quantitative manner, and reveal the interference degree of cross-reactivity from nontarget animals to genetic markers, which will facilitate tracking of multiple faecal pollution sources and planning timely remedial strategies in China.
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Affiliation(s)
- Yang Zhang
- Department of Water Resources and Environment, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Renren Wu
- The Key Laboratory of Water and Air Pollution Control of Guangdong Province, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510000, PR China; State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510530, PR China.
| | - Kairong Lin
- Department of Water Resources and Environment, Sun Yat-sen University, Guangzhou, 510275, PR China.
| | - Yishu Wang
- The Key Laboratory of Water and Air Pollution Control of Guangdong Province, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510000, PR China; State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510530, PR China
| | - Junqing Lu
- The Key Laboratory of Water and Air Pollution Control of Guangdong Province, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510000, PR China; State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Guangzhou, 510530, PR China
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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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29
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Murphy HM, McGinnis S, Blunt R, Stokdyk J, Wu J, Cagle A, Denno DM, Spencer S, Firnstahl A, Borchardt MA. Septic Systems and Rainfall Influence Human Fecal Marker and Indicator Organism Occurrence in Private Wells in Southeastern Pennsylvania. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3159-3168. [PMID: 32073835 DOI: 10.1021/acs.est.9b05405] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In the United States, approximately 48 million people are served by private wells. Unlike public water systems, private well water quality is not monitored, and there are few studies on the extent and sources of contamination of private wells. We extensively investigated five private wells to understand the variability in microbial contamination, the role of septic systems as sources of contamination, and the effect of rainfall on well water quality. From 2016 to 2017, weekly or biweekly samples (n = 105) were collected from five private wells in rural Pennsylvania. Samples were tested for general water quality parameters, conventional and sewage-associated microbial indicators, and human pathogens. Total coliforms, human Bacteroides (HF183), and pepper mild mottle virus were detected at least once in all wells. Regression revealed significant relationships between HF183 and rainfall 8-14 days prior to sampling and between total coliforms and rainfall 8-14 or 0-14 days prior to sampling. Dye tracer studies at three wells confirmed the impact of household septic systems on well contamination. Microbiological measurements, chemical water quality data, and dye tracer tests provide evidence of human fecal contamination in the private wells studied, suggesting that household septic systems are the source of this contamination.
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Affiliation(s)
- Heather M Murphy
- Water, Health and Applied Microbiology Laboratory (WHAM Laboratory), Temple University, Philadelphia, Pennsylvania 19122, United States
- College of Public Health, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Shannon McGinnis
- Water, Health and Applied Microbiology Laboratory (WHAM Laboratory), Temple University, Philadelphia, Pennsylvania 19122, United States
- College of Public Health, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Ryan Blunt
- Water, Health and Applied Microbiology Laboratory (WHAM Laboratory), Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Joel Stokdyk
- United States Geological Survey (USGS), Upper Midwest Water Science Center, Marshfield, Wisconsin 54449, United States
| | - Jingwei Wu
- College of Public Health, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Alexander Cagle
- Water, Health and Applied Microbiology Laboratory (WHAM Laboratory), Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Donna M Denno
- Department of Pediatrics, University of Washington, Seattle, Washington 98115, United States
| | - Susan Spencer
- United States Department of Agriculture (USDA), Agricultural Research Service, Marshfield, Wisconsin 54449, United States
| | - Aaron Firnstahl
- United States Geological Survey (USGS), Upper Midwest Water Science Center, Marshfield, Wisconsin 54449, United States
| | - Mark A Borchardt
- United States Department of Agriculture (USDA), Agricultural Research Service, Marshfield, Wisconsin 54449, United States
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30
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Brooks YM, Spirito CM, Bae JS, Hong A, Mosier EM, Sausele DJ, Fernandez-Baca CP, Epstein JL, Shapley DJ, Goodman LB, Anderson RR, Glaser AL, Richardson RE. Fecal indicator bacteria, fecal source tracking markers, and pathogens detected in two Hudson River tributaries. WATER RESEARCH 2020; 171:115342. [PMID: 31841955 DOI: 10.1016/j.watres.2019.115342] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 05/08/2023]
Abstract
Volunteer monitoring in the Hudson River watershed since 2012 has identified that the Wallkill River and Rondout Creek tributary complex have elevated concentrations of the fecal indicator bacteria, enterococci. Concentrations of enterococci do not provide insight into the sources of pollution and are imperfect indicators of health risks. In 2017, the regular monthly volunteer monitoring campaign for culturable enterococci at 24 sites on the Wallkill and Rondout expanded to include: (1) culturable measurements of E. coli and quantification of E. coli and Enterococcus specific markers vis nanoscale qPCR, (2) microbial source tracking (MST) assays (avian, human, bovine, and equine) via real time PCR and nanoscale qPCR, and 3) quantification of 12 gastrointestinal pathogens including viruses, bacteria, and protozoa via nanoscale qPCR. Three human associated MST markers (HumM2, HF183, and B. theta) corroborated that human pollution was present in Rondout Creek and widespread in the Wallkill River. The presence of B. theta was associated with increased concentrations of culturable E. coli. Genes for adenovirus 40 and 41 conserved region, rotavirus A NSP3, E. coli eae and stx1, and Giardia lamblia 18S rRNA were detected in >45% of samples. Abundance of rotavirus A NSP3 genes was significantly correlated to the bovine marker gene, CowM3, though wild bird sources cannot be ruled out. This is the first study to investigate potential fecal pollution sources and pathogen concentrations in Hudson tributaries during the months of peak recreational use.
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Affiliation(s)
- Yolanda M Brooks
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Catherine M Spirito
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Justin S Bae
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Anna Hong
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Emma M Mosier
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Desiree J Sausele
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | | | | | - Dan J Shapley
- Riverkeeper Inc, 20 Secor Road, Ossining, NY, 10562, USA
| | - Laura B Goodman
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Renee R Anderson
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Amy L Glaser
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Ruth E Richardson
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA.
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31
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Ecological and Technical Mechanisms for Cross-Reaction of Human Fecal Indicators with Animal Hosts. Appl Environ Microbiol 2020; 86:AEM.02319-19. [PMID: 31862726 DOI: 10.1128/aem.02319-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/15/2019] [Indexed: 12/13/2022] Open
Abstract
Quantitative PCR (qPCR) assays for human/sewage marker genes have demonstrated sporadic positive results in animal feces despite their high specificities to sewage and human feces. It is unclear whether these positive reactions are caused by true occurrences of microorganisms containing the marker gene (i.e., indicator organisms) or nonspecific amplification (false positive). The distribution patterns of human/sewage indicator organisms in animals have not been explored in depth, which is crucial for evaluating a marker gene's true- or false-positive reactions. Here, we analyzed V6 region 16S rRNA gene sequences from 257 animal fecal samples and tested a subset of 184 using qPCR for human/sewage marker genes. Overall, specificities of human/sewage marker genes within sequencing data were 99.6% (BacV6-21), 96.9% (Lachno3), and 96.1% (HF183, indexed by its inferred V6 sequence). Occurrence of some true cross-reactions was associated with atypical compositions of organisms within the genera Blautia or Bacteroides For human/sewage marker qPCR assays, specificities were 96.7% (HF183/Bac287R), 96.2% (BacV6-21), 95.6% (human Bacteroides [HB]), and 94.0% (Lachno3). Select assays duplexed with either Escherichia coli or Enterococcus spp. were also validated. Most of the positive qPCR results in animals were low level and, on average, 2 orders of magnitude lower than the copy numbers of E. coli and Enterococcus spp. The lower specificity in qPCR assays compared to sequencing data was mainly caused by amplification of sequences highly similar to the marker gene and not the occurrence of the exact marker sequence in animal fecal samples.IMPORTANCE Identifying human sources of fecal pollution is critical to remediate sanitation concerns. Large financial investments are required to address these concerns; therefore, a high level of confidence in testing results is needed. Human fecal marker genes validated in this study showed high specificity in both sequencing data and qPCR results. Human marker sequences were rarely found in individual animals, and in most cases, the animals had atypical microbial communities. Sequencing also revealed the presence of closely related organisms that could account for nonspecific amplification in certain assays. Both the true cross-reactions and the nonspecific amplification had low signals well below E. coli or Enterococcus levels and likely would not impact the assay's ability to reliably detect human fecal pollution. No animal source had multiple human/sewage marker genes present; therefore, using a combination of marker genes would increase the confidence of human fecal pollution detection.
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32
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Jeong SH, Shin SB, Lee JH, Kwon JY, Lee HC, Kim SJ, Ha KS. Level of contamination in the feces of several species at major inland pollution sources in the drainage basin of Yeoja Bay, Republic of Korea. ENVIRONMENTAL MONITORING AND ASSESSMENT 2020; 192:170. [PMID: 32034525 DOI: 10.1007/s10661-020-8131-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 01/30/2020] [Indexed: 06/10/2023]
Abstract
We assessed the levels of fecal contamination and the originating species of 12 major inland pollutants in the drainage basin of Yeoja Bay. The presence of the human-specific (HF183), ruminant-specific (BacR and Rum-2-Bac), pig-specific (Pig-Bac-2 and Pig-2-Bac), avian-specific (GFD), and gull-specific (Gull2) markers in water samples (n = 34) from 12 inland pollution sources around Yeoja Bay was analyzed. HF183 was detected in 97% of the water samples, and all major inland pollution sources were contaminated with human feces. BacR and Rum-2-Bac were detected in 94% and 11%, respectively, of the water samples. Pig-2-Bac was not detected in the inland pollution sources, but site L5 might be contaminated with swine feces. Gull2 was not detected, whereas GFD was detected in 26% of the water samples. This study highlights the utility of a MST toolbox approach for characterizing the water quality of inland pollution sources and identifying the feces producing species.
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Affiliation(s)
- Sang Hyeon Jeong
- Southeast Sea Fisheries Research Institute, National Institute of Fisheries Science, 397-68, Sanyangilju-ro, Sanyang-eup, Tongyeong-si, Gyeongsangnam-do, 53085, Republic of Korea.
| | - Soon Bum Shin
- South Sea Fisheries Research Institute, National Institute of Fisheries Science, 22, Sepodangmeori-gil, Hwayang-myeon, Yeosu-si, Jeollanam-do, 59780, Republic of Korea
| | - Ji Hee Lee
- South Sea Fisheries Research Institute, National Institute of Fisheries Science, 22, Sepodangmeori-gil, Hwayang-myeon, Yeosu-si, Jeollanam-do, 59780, Republic of Korea
| | - Ji Young Kwon
- Southeast Sea Fisheries Research Institute, National Institute of Fisheries Science, 397-68, Sanyangilju-ro, Sanyang-eup, Tongyeong-si, Gyeongsangnam-do, 53085, Republic of Korea
| | - Hee Chung Lee
- Southeast Sea Fisheries Research Institute, National Institute of Fisheries Science, 397-68, Sanyangilju-ro, Sanyang-eup, Tongyeong-si, Gyeongsangnam-do, 53085, Republic of Korea
| | - Seon-Jae Kim
- Department of Marine Bio Food Science, Chonnam National University, 50, Daehak-ro, Yeosu-si, Jeollanam-do, 59626, Republic of Korea
| | - Kwang Soo Ha
- Southeast Sea Fisheries Research Institute, National Institute of Fisheries Science, 397-68, Sanyangilju-ro, Sanyang-eup, Tongyeong-si, Gyeongsangnam-do, 53085, Republic of Korea
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33
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Tanvir Pasha ABM, Hinojosa J, Phan D, Lopez A, Kapoor V. Detection of human fecal pollution in environmental waters using human mitochondrial DNA and correlation with general and human-associated fecal genetic markers. JOURNAL OF WATER AND HEALTH 2020; 18:8-18. [PMID: 32129182 DOI: 10.2166/wh.2019.197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Human mitochondrial DNA (mtDNA) genetic markers are abundant in sewage and highly human-specific, suggesting a great potential for the environmental application as human fecal pollution indicators. Limited data are available on the occurrence and co-occurrence of human mtDNA with fecal bacterial markers in surface waters, and how the abundance of these markers is influenced by rain events. A 1-year sampling study was conducted in a suburban watershed impacted by human sewage contamination to evaluate the performance of a human mtDNA-based marker along with the bacterial genetic markers for human-associated Bacteroidales (BacHum and HF183) and Escherichia coli. Additionally, the human mtDNA-based assay was correlated with rain events and other markers. The mtDNA marker was detected in 92% of samples (n = 140) with a mean concentration of 2.96 log10 copies/100 ml throughout the study period. Human mtDNA was detected with greater abundance than human-associated Bacteroidales that could be attributed to differences in the decay of these markers in the environment. The abundance of all markers was positively correlated with rain events, and human mtDNA abundance was significantly correlated with various bacterial markers. In general, these results should support future risk assessment for impacted watersheds, particularly those affected by human fecal pollution, by evaluating the performance of these markers during rain events.
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Affiliation(s)
- A B M Tanvir Pasha
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA E-mail:
| | - Jessica Hinojosa
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA E-mail:
| | - Duc Phan
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA E-mail:
| | - Adrianne Lopez
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA E-mail:
| | - Vikram Kapoor
- Department of Civil and Environmental Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA E-mail:
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Curtis K, Gonzalez RA. Integrating Bayesian Analysis and Cumulative Probability Generates High Confidence Using a Single Microbial Source Tracking Marker. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:13929-13937. [PMID: 31682415 DOI: 10.1021/acs.est.9b03843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microbial source tracking can identify waterbodies at risk of contamination using host-associated molecular markers. No assay used for microbial source tracking is both 100% host-specific and sensitive for human or animal fecal contamination. Using literature sensitivity and specificity values, Bayes' Theorem for conditional probability was applied to the human fecal-associated HF183 marker in a microbial source tracking context. Type I and Type II error rates were examined across a range of priors. Conditional probabilities were investigated using two human-associated markers, HF183 and HumM2, concurrently. Cumulative probability analysis was used to explore the likelihood of true contaminant detection using multiple samples. Probability of human fecal contamination was calculated for all combinations of positive and negative marker results given three samples. Results demonstrate the respective influence that specificity and sensitivity values exert on the likelihood of true positive and true negative. Using practical priors, high levels of confidence (99%) in results were observed when HF183 and HumM2 were used concurrently. Cumulative probability analyses showed that multiple samples from a single location can provide a >95% level of confidence in positive and negative results, suggesting that when multiple samples are necessary to account for in situ variability, a single marker can yield sufficiently reliable results.
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Affiliation(s)
- Kyle Curtis
- Hampton Roads Sanitation District , 1434 Air Rail Blvd , Virginia Beach , Virginia 23455 , United States
| | - Raul A Gonzalez
- Hampton Roads Sanitation District , 1434 Air Rail Blvd , Virginia Beach , Virginia 23455 , United States
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35
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Gorski L, Rivadeneira P, Cooley MB. New strategies for the enumeration of enteric pathogens in water. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:765-776. [PMID: 31342654 DOI: 10.1111/1758-2229.12786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/15/2019] [Accepted: 07/21/2019] [Indexed: 06/10/2023]
Abstract
Water quality standards for drinking water and recreational waters have long been based on the enumeration of faecal coliforms in the various water supplies, with 0 CFU Escherichia coli/100 ml for drinking water and <126 CFU generic E. coli/100 ml for recreational waters. Irrigation water will soon undergo the same scrutiny in the United States. For over 50 years the most probable number method has been used by laboratories to estimate the level of viable bacteria in a sample, but this method is labour intensive and slow, especially if large numbers of samples need to be tested. In this review, we describe some recent innovations in methods to enumerate enteric pathogens in water. These methods are based on different reasoning schemes that can be categorized as biosensors and nucleic acid-based methods. All the methods described here used natural water sources. Several were also used to survey the bacterial levels in naturally contaminated samples. The different methods vary in their limits of detection, ease of use, and potential portability. Some combine very good limits of detection with the ability to overcome technical challenges; however, there is considerable room for improvement, as none of the methods are without shortcomings.
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Affiliation(s)
- Lisa Gorski
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA
| | - Paula Rivadeneira
- Department of Soil, Water, and Environmental Science, The University of Arizona, Yuma, AZ, USA
| | - Michael B Cooley
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, USA
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36
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Senkbeil JK, Ahmed W, Conrad J, Harwood VJ. Use of Escherichia coli genes associated with human sewage to track fecal contamination source in subtropical waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:1069-1075. [PMID: 31200304 DOI: 10.1016/j.scitotenv.2019.05.201] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
Escherichia coli (E. coli) is frequently used in assessment and regulation of recreational water quality, but it is a general fecal indicator that provides no information about fecal contamination source. Sewage-associated microorganisms and related marker genes have proven useful for microbial source tracking (MST) applications that link fecal contamination to host sources, but many MST marker genes are carried in taxa not used in regulatory contexts. A more direct connection with regulatory concerns, including human health risk and total maximum daily load (TMDL) assessments, could be accomplished with tools such as the human-associated marker genes of E. coli. We evaluated the performance of E. coli H8, H12, H14, and H24 marker genes for detection of domestic sewage at the E. coli isolate level in Florida. E. coli isolates (n = 1, 380) from reference fecal and wastewater samples were first tested by binary PCR for the presence of each H marker gene. H8 and H12 were >90% specific and sensitive for domestic sewage, while H14 and H24 were ≤86% specific. Therefore, quantitative PCR (qPCR) assays were used to quantify H8 and H12 marker genes at the sample level. Specificity values for the H8 and H12 qPCR assays were 96 and 93%, respectively, while both marker genes showed 100% sensitivity. H12 concentrations were tenfold lower in wastewater than H8 (~6-7 log10 gene copies (GC)/100 mL). H8 concentrations in wastewater and contaminated environmental water samples were correlated with the sewage-associated Bacteroides HF183 marker gene. This study suggests that E. coli H genes, and H8 in particular, can be useful for sewage contamination tracking and TMDL development in subtropical waters.
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Affiliation(s)
- Jacob K Senkbeil
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, United States of America
| | - Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia.
| | - James Conrad
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, United States of America
| | - Valerie J Harwood
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, United States of America
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37
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Xue J, Feng Y. Comparison of microbial source tracking efficacy for detection of cattle fecal contamination by quantitative PCR. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:1104-1112. [PMID: 31412506 DOI: 10.1016/j.scitotenv.2019.06.091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 06/06/2019] [Accepted: 06/06/2019] [Indexed: 06/10/2023]
Abstract
Identification of fecal contamination sources in surface water has become heavily dependent on quantitative PCR (qPCR) because this technique allows for the rapid enumeration of fecal indicator bacteria as well as the detection and quantification of fecal source-associated genetic markers in the environment. Identification of contamination sources in impaired waters is a prerequisite for developing best management practices to reduce future pollution. Proper management decisions rely on the quality and interpretation of qPCR data. In this study, we developed a method to determine analytical and process lower limits of detection (LLOD) and quantification (LLOQ) using two cattle-associated genetic markers targeting Bacteroidales. Analytical LLOD (ALLOD) for both CowM2 and CowM3 genetic markers in the qPCR assay were five gene copies per reaction. Using composite fecal DNA, the analytical LLOQ (ALLOQ) determined for CowM2 and CowM3 were 78 and 195 gene copies/reaction, respectively. When plasmid DNA was used, the ALLOQ for CowM2 and CowM3 were 46 and 20 gene copies/reaction, respectively. The process LLOD (PLLOD) for CowM2 and CowM3 were 0.4 and 0.02 mg feces/filter (wet weight), respectively. Using the standard deviation value of 0.25 as a cut-off point for LLOQ in regression analysis, the process LLOQ (PLLOQ) for CowM2 and CowM3 were 3.2 and 0.3 mg feces/filter, respectively. These results indicate that CowM3 exhibited superior performance characteristics compared with CowM2 for fecal samples collected from our geographical region. Moreover, the method for calculating LLOD and LLOQ developed here can be applied to other microbial source tracking studies.
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Affiliation(s)
- Jia Xue
- Department of Crop, Soil and Environmental Sciences, Auburn University, AL 36849, USA.
| | - Yucheng Feng
- Department of Crop, Soil and Environmental Sciences, Auburn University, AL 36849, USA.
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Blumensaat F, Leitão JP, Ort C, Rieckermann J, Scheidegger A, Vanrolleghem PA, Villez K. How Urban Storm- and Wastewater Management Prepares for Emerging Opportunities and Threats: Digital Transformation, Ubiquitous Sensing, New Data Sources, and Beyond - A Horizon Scan. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8488-8498. [PMID: 31291095 DOI: 10.1021/acs.est.8b06481] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ubiquitous sensing will create many opportunities and threats for urban water management, which are only poorly understood today. To identify the most relevant trends, we conducted a horizon scan regarding how ubiquitous sensing will shape the future of urban drainage and wastewater management. Our survey of the international urban water community received an active response from both the academics and the professionals from the water industry. The analysis of the responses demonstrates that emerging topics for urban water will often involve experts from different communities, including aquatic ecologists, urban water system engineers and managers, as well as information and communications technology professionals and computer scientists. Activities in topics that are identified as novel will either require (i) cross-disciplinary training, such as importing new developments from the IT sector, or (ii) research in new areas for urban water specialists, for example, to help solve open questions in aquatic ecology. These results are, therefore, a call for interdisciplinary research beyond our own discipline. They also demonstrate that the water management community is not yet prepared for the digital transformation, where we will experience a data demand, i.e. a "pull" of urban water data into external services. The results suggest that a lot remains to be done to harvest the upcoming opportunities. Horizon scanning should be repeated on a routine basis, under the umbrella of an experienced polling organization.
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Affiliation(s)
- Frank Blumensaat
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
- Institute of Environmental Engineering, Chair of Urban Water Systems , ETH Zurich , Stefano-Franscini-Platz 5 , 8093 Zurich , Switzerland
| | - João P Leitão
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
| | - Christoph Ort
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
| | - Jörg Rieckermann
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
| | - Andreas Scheidegger
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
| | - Peter A Vanrolleghem
- modelEAU, Université Laval , Département de génie civil et de génie des eaux , 1065 av. de la Médecine , Québec , Québec G1 V 0A6 , Canada
- CentrEau , Université Laval , 1065 av. de la Médecine , Québec , Québec G1 V 0A6 , Canada
| | - Kris Villez
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
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Vadde KK, McCarthy AJ, Rong R, Sekar R. Quantification of Microbial Source Tracking and Pathogenic Bacterial Markers in Water and Sediments of Tiaoxi River (Taihu Watershed). Front Microbiol 2019; 10:699. [PMID: 31105648 PMCID: PMC6492492 DOI: 10.3389/fmicb.2019.00699] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/20/2019] [Indexed: 12/13/2022] Open
Abstract
Taihu Lake is one of the largest freshwater lakes in China, serving as an important source of drinking water; >60% of source water to this lake is provided by the Tiaoxi River. This river faces serious fecal contamination issues, and therefore, a comprehensive investigation to identify the sources of fecal contamination was carried out and is presented here. The performance of existing universal (BacUni and GenBac), human (HF183-Taqman, HF183-SYBR, BacHum, and Hum2), swine (Pig-2-Bac), ruminant (BacCow), and avian (AV4143 and GFD) associated microbial source tracking (MST) markers was evaluated prior to their application in this region. The specificity and sensitivity results indicated that BacUni, HF183-TaqMan, Pig-2-Bac, and GFD assays are the most suitable in identifying human and animal fecal contamination. Therefore, these markers along with marker genes specific to selected bacterial pathogens were quantified in water and sediment samples of the Tiaoxi River, collected from 15 locations over three seasons during 2014 and 2015. Total/universal Bacteroidales markers were detected in all water and sediment samples (mean concentration 6.22 log10 gene copies/100 ml and 6.11 log10 gene copies/gram, respectively), however, the detection of host-associated MST markers varied. Human and avian markers were the most frequently detected in water samples (97 and 89%, respectively), whereas in sediment samples, only human-associated markers were detected more often (86%) than swine (64%) and avian (8.8%) markers. The results indicate that several locations in the Tiaoxi River are heavily polluted by fecal contamination and this correlated well with land use patterns. Among the five bacterial pathogens tested, Shigella spp. and Campylobacter jejuni were the most frequently detected pathogens in water (60% and 62%, respectively) and sediment samples (91% and 53%, respectively). Shiga toxin-producing Escherichia coli (STEC) and pathogenic Leptospira spp. were less frequently detected in water samples (55% and 33%, respectively) and sediment samples (51% and 13%, respectively), whereas E. coli O157:H7 was only detected in sediment samples (11%). Overall, the higher prevalence and concentrations of Campylobacter jejuni, Shigella spp., and STEC, along with the MST marker detection at a number of locations in the Tiaoxi River, indicates poor water quality and a significant human health risk associated with this watercourse. GRAPHICAL ABSTRACTTracking fecal contamination and pathogens in watersheds using molecular methods.
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Affiliation(s)
- Kiran Kumar Vadde
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, China
| | - Alan J. McCarthy
- Microbiology Research Group, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Rong Rong
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, China
| | - Raju Sekar
- Department of Biological Sciences, Xi’an Jiaotong-Liverpool University, Suzhou, China
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Nguyen KH, Senay C, Young S, Nayak B, Lobos A, Conrad J, Harwood VJ. Determination of wild animal sources of fecal indicator bacteria by microbial source tracking (MST) influences regulatory decisions. WATER RESEARCH 2018; 144:424-434. [PMID: 30059905 DOI: 10.1016/j.watres.2018.07.034] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 07/05/2018] [Accepted: 07/14/2018] [Indexed: 05/13/2023]
Abstract
Fecal indicator bacteria (FIB) are used to assess fecal pollution levels in surface water and are among the criteria used by regulatory agencies to determine water body impairment status. While FIB provide no information about pollution source, microbial source tracking (MST) does, which contributes to more direct and cost effective remediation efforts. We studied a watershed in Florida managed for wildlife conservation that historically exceeded the state regulatory guideline for fecal coliforms. We measured fecal coliforms, enterococci, a marker gene for avian feces (GFD), and a marker gene for human-associated Bacteroides (HF183) in sediment, vegetation, and water samples collected monthly from six sites over two years to: 1) assess the influence of site, temporal factors, and habitat (sediment, vegetation, and water) on FIB and MST marker concentrations, 2) test for correlations among FIB and MST markers, and 3) determine if avian feces and/or human sewage contributed to FIB levels. Sediment and vegetation had significantly higher concentrations of FIB and GFD compared to water and thus may serve as microbial reservoirs, providing unreliable indications of recent contamination. HF183 concentrations were greatest in water samples but were generally near the assay limit of detection. HF183-positive results were attributed to white-tailed deer (Odocoileus virginianus) feces, which provided a false indication of human sewage in this water body. FIB and GFD were positively correlated while FIB and HF183 were negatively correlated. We demonstrated that birds, not sewage, were the main source of FIB, thus avoiding implementation of a total maximum daily load program (TMDL). Our results demonstrate that the concomitant use of FIB and MST can improve decision-making and provide direction when water bodies are impaired, and provides a strategy for natural source exclusion in water bodies impacted by wild animal feces.
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Affiliation(s)
- K H Nguyen
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - C Senay
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - S Young
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - B Nayak
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - A Lobos
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - J Conrad
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA
| | - V J Harwood
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Avenue, SCA 110, Tampa, FL 33620, USA.
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Zimmer-Faust AG, Thulsiraj V, Lee CM, Whitener V, Rugh M, Mendoza-Espinosa L, Jay JA. Multi-tiered approach utilizing microbial source tracking and human associated-IMS/ATP for surveillance of human fecal contamination in Baja California, Mexico. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 640-641:475-484. [PMID: 29864661 DOI: 10.1016/j.scitotenv.2018.05.172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 06/08/2023]
Abstract
As both the need for reuse of reclaimed wastewater and the burden placed on existing wastewater treatment plants increase, so does the need for methods that can reliably, rapidly and economically identify human-associated contamination. A survey of surface water quality was conducted in Baja California, Mexico where inadequate infrastructure or its inefficient operation leads to poor water quality. The HF183 and Bacteroides thetaiotaomicron (B. theta) human-associated gene markers were detected in 84% and 82% of samples collected during dry weather, illustrating evidence of widespread human fecal contamination. In addition, an inversely-coupled (Inv-IMS/ATP) viability-based assay for detection of B. theta was developed and applied for rapid detection and screening of human-associated fecal contamination. The Inv-IMS/ATP assay was able to effectively differentiate between surface waters impacted with human fecal contamination, and B. theta levels measured by Inv-IMS/ATP were highly correlated with HF183 and B. theta human marker measurements (r = 0.76; r = 0.82) in complex surface water samples. In areas with widespread human fecal contamination and limited access to more expensive methods, a multi-pronged approach utilizing a combination of methods including the Inv-IMS/ATP assay for rapid evaluation and screening of surface water quality alongside human-associated genetic markers may improve risk assessment and surveillance capabilities.
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Affiliation(s)
- Amity G Zimmer-Faust
- Western Ecology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Currently at Southern California Coastal Water Research Project, Costa Mesa, CA, USA.
| | - Vanessa Thulsiraj
- Biology Department, Mount Saint Mary's University, 12001 Chalon Road, Los Angeles, CA 90049, USA
| | - Christine M Lee
- Earth Science Division, American Association for the Advancement of Science, National Aeronautics and Space Administration Headquarters, WA, USA
| | - Victoria Whitener
- Department of Civil and Environmental Engineering, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Megan Rugh
- Department of Civil and Environmental Engineering, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | | | - Jennifer A Jay
- Department of Civil and Environmental Engineering, University of California at Los Angeles, Los Angeles, CA 90095, USA
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Nshimyimana JP, Martin SL, Flood M, Verhougstraete MP, Hyndman DW, Rose JB. Regional Variations of Bovine and Porcine Fecal Pollution as a Function of Landscape, Nutrient, and Hydrological Factors. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:1024-1032. [PMID: 30272781 DOI: 10.2134/jeq2017.11.0438] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The effects of manure application in agriculture on surface water quality has become a local to global problem because of the adverse consequences on public health and food security. This study evaluated (i) the spatial distribution of bovine (cow) and porcine (pig) genetic fecal markers, (ii) how hydrologic factors influenced these genetic markers, and (iii) their variations as a function of land use, nutrients, and other physiochemical factors. We collected 189 samples from 63 watersheds in Michigan's Lower Peninsula during baseflow, spring melt, and summer rain conditions. For each sample, we quantified the concentrations of bovine and porcine genetic markers by digital droplet polymerase chain reaction and measured , dissolved oxygen, pH, temperature, total phosphorus, total nitrogen, nitrate-nitrite (NO), ammonia (NH), soluble reactive phosphorus, streamflow, and watershed specific precipitation. Bovine and porcine manure markers were ubiquitous in rivers that drain agricultural and natural fields across the study region. This study provides baseline conditions on the state of watershed impairment, which can be used to develop best management practices that could improve water quality. Similar studies should be performed with higher spatial sampling density to elucidate detailed factors that influence the transport of manure constituents.
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Aslan A, Anderson KW, Chapman A. The Impact of Tides on Microbial Water Quality at an Inland River Beach. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:1123-1129. [PMID: 30272796 DOI: 10.2134/jeq2017.12.0499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Most coastal freshwater ecosystems in the United States have semi-tidal movements during the day. Routine monitoring of these environments is conducted once during the day when tides can be at either ebb or flood conditions, causing a variability in bacterial concentrations and misinterpretation of the illness risk associated with human activities. The occurrence and levels of enterococci (enterococci 23S rDNA [Ent23S]) and human- (HF183) and avian- (GFD) associated microbial source tracking (MST) markers were investigated using quantitative polymerase chain reaction (qPCR) along with detection of culturable enterococci and environmental parameters. Samples were collected during flood and ebb tide conditions (May-September) from a tidal river used for recreational activities. Culturable enterococci [(420) = 2.093, = 0.040] and Ent23S [(420) = 2.243, = 0.028] controlled for tide type were significantly different; higher enterococci concentrations were detected during the flood tide. Among all samples, 6% were positive for HF183, and GFD was positively correlated with Ent23S ( = 0.92, = 0.029) and conductivity ( = 0.93, = 0.023) during flood tide. Unlike the general assumption that ebb tide flow in a river would likely carry runoff from the land, the microbial contaminants in this case were transported from upstream via ocean water to the river during the flood tide. These results suggest that hydrology and land use patterns must be considered in sampling design when conducting future microbial water quality monitoring programs to better characterize recreational water safety in tidal rivers.
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Nevers MB, Byappanahalli MN, Shively D, Buszka PM, Jackson PR, Phanikumar MS. Identifying and Eliminating Sources of Recreational Water Quality Degradation along an Urban Coast. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:1042-1050. [PMID: 30272790 DOI: 10.2134/jeq2017.11.0461] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Restoration of highly degraded urban coastal waters often requires large-scale, complex projects, but in the interim, smaller-scale efforts can provide immediate improvements to water quality conditions for visitor use. We examined short-term efforts to improve recreational water quality near the Grand Calumet River (GC) in the Laurentian Great Lakes. Identified as an Area of Concern (AOC) by the International Joint Commission, the GC has experienced years of industrial and municipal waste discharges, and as a result, coastal beaches have some of the highest rates of beach closings (>70%) in the United States. Project objectives were to identify sources of microbial contamination and to evaluate a short-term management solution to decrease beach closings: during 2015 (partial) and 2016 (season-long), canines were used to deter gull presence. Water samples were analyzed for in 2015 and 2016, and fecal sources were evaluated using microbial source tracking markers (2015): human ( HF183, ), gull (Gull2), and dog (DogBact). Hydrometeorological conditions were simultaneously measured. Results indicated that human, gull, and canine fecal sources were present, with gulls being the dominant source. densities were highly correlated with number of gulls present, Gull2 marker, and turbidity. Gull deterrence decreased and Gull2 marker detection during 2015, but numbers rebounded after program completion. The full-season program in 2016 resulted in lower densities and fewer beach closings. Large-scale restoration efforts are underway at this location, but short-term, small-scale projects can be useful for reducing beach closings and restoring ecosystem services.
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Ballesté E, García-Aljaro C, Blanch AR. Assessment of the decay rates of microbial source tracking molecular markers and faecal indicator bacteria from different sources. J Appl Microbiol 2018; 125:1938-1949. [PMID: 30066371 DOI: 10.1111/jam.14058] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 07/11/2018] [Accepted: 07/28/2018] [Indexed: 01/18/2023]
Abstract
AIMS Evaluate the T90 and compare the decay of different faecal indicator bacteria (FIB) and molecular microbial source tracking (MST) markers of human and animal sources during summer and winter. METHODS AND RESULTS The persistence of Escherichia coli and enterococci and several MST molecular markers targeting host-specific Bifidobacterium and Bacteroidales species (BifHM, BifCW, BifPL, HF183/BFD, Rum2Bac and Pig2Bac) was assessed at the same time using mesocosms. Dialysis bags filled with diluted wastewater from different sources were kept in an outdoor water tank and monitored regularly to assess the inactivation rates. The T90 values of E. coli by culture methods ranged from 1·52 to 5·69 days in summer and 2·06 to 6·19 days in winter, whereas with qPCR 2·29-4·23 days in summer and 4·17-8·09 days in winter. T90 values for enterocci ranged from 1·15 to 3·10 days in summer and from 3·01 to 5·46 days in winter. Significant differences were observed between faecal sources for both markers. For the MST makers similar T90 values were obtained in summer (1·05-1·91 days), whereas higher variability was observed in winter (2·90-6·12 days). CONCLUSIONS Different decay rates were observed for the FIB from the different sources, especially for E. coli in ruminant samples. A higher variability among T90 values of the different MST markers in winter was observed, whereas similar T90 values were detected in summer highlighting the stronger effect of environmental parameters during this season. SIGNIFICANCE AND IMPACT OF THE STUDY The diverse inactivation rates observed in bacteria from different faecal sources have implications when these rates are used to model faecal pollution in water. The use of FIBT90 of different sources is essential to develop reliable predictive models. Since different inactivation of E. coli regarding the source of pollution has been observed, the source of the pollution has to be considered for modelling approaches.
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Affiliation(s)
- E Ballesté
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Catalonia, Spain
| | - C García-Aljaro
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Catalonia, Spain
| | - A R Blanch
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Catalonia, Spain
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Human-Associated Lachnospiraceae Genetic Markers Improve Detection of Fecal Pollution Sources in Urban Waters. Appl Environ Microbiol 2018; 84:AEM.00309-18. [PMID: 29728386 DOI: 10.1128/aem.00309-18] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/24/2018] [Indexed: 11/20/2022] Open
Abstract
The human microbiome contains many organisms that could potentially be used as indicators of human fecal pollution. Here we report the development of two novel human-associated genetic marker assays that target organisms within the family Lachnospiraceae Next-generation sequencing of the V6 region of the 16S rRNA gene from sewage and animal stool samples identified 40 human-associated marker candidates with a robust signal in sewage and low or no occurrence in samples from nonhuman hosts. Two were chosen for quantitative PCR (qPCR) assay development using longer sequences (the V2 to V9 regions) generated from clone libraries. Validation of these assays with these markers, designated Lachno3 and Lachno12, was performed using fecal samples (n = 55) from cat, dog, pig, cow, deer, and gull sources, and the results were compared with those of established host-associated assays (the Lachno2 marker and two human Bacteroides markers, the HB and HF183/BacR287). Each of the established assays cross-reacted with samples from at least one other animal species, including animals common in urban areas. The Lachno3 and Lachno12 markers were primarily human associated; however, the Lachno12 marker demonstrated low levels of cross-reactivity with samples from select cows and nonspecific amplification with samples from pigs. This limitation may not be problematic when testing urban waters. These novel markers resolved ambiguous results from previous investigations of stormwater-impacted waters, demonstrating their utility. The complexity of the microbiome in humans and animals suggests that no single organism is strictly specific to humans, and the use of multiple complementary markers in combination will provide the highest resolution and specificity for assessing fecal pollution sources.IMPORTANCE Traditional fecal indicator bacteria do not distinguish animal from human fecal pollution, which is necessary to evaluate health risks and mitigate pollution sources. Assessing water in urban areas is challenging, since the water can be impacted by sewage, which has a high likelihood of carrying human pathogens, as well as pet and urban wildlife waste. We demonstrate that the Lachno3 and Lachno12 markers are human associated and highly specific for the detection of human fecal pollution from urban sources, offering reliable identification of fecal pollution sources in urban waters.
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Steele JA, Blackwood AD, Griffith JF, Noble RT, Schiff KC. Quantification of pathogens and markers of fecal contamination during storm events along popular surfing beaches in San Diego, California. WATER RESEARCH 2018; 136:137-149. [PMID: 29501758 DOI: 10.1016/j.watres.2018.01.056] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 01/19/2018] [Accepted: 01/24/2018] [Indexed: 05/08/2023]
Abstract
Along southern California beaches, the concentrations of fecal indicator bacteria (FIB) used to quantify the potential presence of fecal contamination in coastal recreational waters have been previously documented to be higher during wet weather conditions (typically winter or spring) than those observed during summer dry weather conditions. FIB are used for management of recreational waters because measurement of the bacterial and viral pathogens that are the potential causes of illness in beachgoers exposed to stormwater can be expensive, time-consuming, and technically difficult. Here, we use droplet digital Polymerase Chain Reaction (digital PCR) and digital reverse transcriptase PCR (digital RT-PCR) assays for direct quantification of pathogenic viruses, pathogenic bacteria, and source-specific markers of fecal contamination in the stormwater discharges. We applied these assays across multiple storm events from two different watersheds that discharge to popular surfing beaches in San Diego, CA. Stormwater discharges had higher FIB concentrations as compared to proximal beaches, often by ten-fold or more during wet weather. Multiple lines of evidence indicated that the stormwater discharges contained human fecal contamination, despite the presence of separate storm sewer and sanitary sewer systems in both watersheds. Human fecal source markers (up to 100% of samples, 20-12440 HF183 copies per 100 ml) and human norovirus (up to 96% of samples, 25-495 NoV copies per 100 ml) were routinely detected in stormwater discharge samples. Potential bacterial pathogens were also detected and quantified: Campylobacter spp. (up to 100% of samples, 16-504 gene copies per 100 ml) and Salmonella (up to 25% of samples, 6-86 gene copies per 100 ml). Other viral human pathogens were also measured, but occurred at generally lower concentrations: adenovirus (detected in up to 22% of samples, 14-41 AdV copies per 100 ml); no enterovirus was detected in any stormwater discharge sample. Higher concentrations of avian source markers were noted in the stormwater discharge located immediately downstream of a large bird sanctuary along with increased Campylobacter concentrations and notably different Campylobacter species composition than the watershed that had no bird sanctuary. This study is one of the few to directly measure an array of important bacterial and viral pathogens in stormwater discharges to recreational beaches, and provides context for stormwater-based management of beaches during high risk wet-weather periods. Furthermore, the combination of culture-based and digital PCR-derived data is demonstrated to be valuable for assessing hydrographic relationships, considering delivery mechanisms, and providing foundational exposure information for risk assessment.
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Affiliation(s)
- Joshua A Steele
- Southern California Coastal Water Research Project, 3535 Harbor Blvd. Ste 110, Costa Mesa, CA 92626, USA.
| | - A Denene Blackwood
- UNC Institute of Marine Science, 3431 Arendell Street, Morehead City, NC 28557, USA
| | - John F Griffith
- Southern California Coastal Water Research Project, 3535 Harbor Blvd. Ste 110, Costa Mesa, CA 92626, USA
| | - Rachel T Noble
- UNC Institute of Marine Science, 3431 Arendell Street, Morehead City, NC 28557, USA
| | - Kenneth C Schiff
- Southern California Coastal Water Research Project, 3535 Harbor Blvd. Ste 110, Costa Mesa, CA 92626, USA
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Mayer R, Reischer GH, Ixenmaier SK, Derx J, Blaschke AP, Ebdon JE, Linke R, Egle L, Ahmed W, Blanch AR, Byamukama D, Savill M, Mushi D, Cristóbal HA, Edge TA, Schade MA, Aslan A, Brooks YM, Sommer R, Masago Y, Sato MI, Taylor HD, Rose JB, Wuertz S, Shanks OC, Piringer H, Mach RL, Savio D, Zessner M, Farnleitner AH. Global Distribution of Human-Associated Fecal Genetic Markers in Reference Samples from Six Continents. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5076-5084. [PMID: 29570973 PMCID: PMC5932593 DOI: 10.1021/acs.est.7b04438] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 03/09/2018] [Accepted: 03/23/2018] [Indexed: 05/19/2023]
Abstract
Numerous bacterial genetic markers are available for the molecular detection of human sources of fecal pollution in environmental waters. However, widespread application is hindered by a lack of knowledge regarding geographical stability, limiting implementation to a small number of well-characterized regions. This study investigates the geographic distribution of five human-associated genetic markers (HF183/BFDrev, HF183/BacR287, BacHum-UCD, BacH, and Lachno2) in municipal wastewaters (raw and treated) from 29 urban and rural wastewater treatment plants (750-4 400 000 population equivalents) from 13 countries spanning six continents. In addition, genetic markers were tested against 280 human and nonhuman fecal samples from domesticated, agricultural and wild animal sources. Findings revealed that all genetic markers are present in consistently high concentrations in raw (median log10 7.2-8.0 marker equivalents (ME) 100 mL-1) and biologically treated wastewater samples (median log10 4.6-6.0 ME 100 mL-1) regardless of location and population. The false positive rates of the various markers in nonhuman fecal samples ranged from 5% to 47%. Results suggest that several genetic markers have considerable potential for measuring human-associated contamination in polluted environmental waters. This will be helpful in water quality monitoring, pollution modeling and health risk assessment (as demonstrated by QMRAcatch) to guide target-oriented water safety management across the globe.
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Affiliation(s)
- René
E. Mayer
- Research
Group Environmental Microbiology and Molecular
Diagnostics 166-5-3, Institute of Chemical, Environmental
and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
| | - Georg H. Reischer
- Research
Group Environmental Microbiology and Molecular
Diagnostics 166-5-3, Institute of Chemical, Environmental
and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
- Molecular
Diagnostics Group, IFA-Tulln, Institute
of Chemical, Environmental and Bioscience Engineering, TU Wien, 3430 Tulln, Austria
| | - Simone K. Ixenmaier
- Research
Group Environmental Microbiology and Molecular
Diagnostics 166-5-3, Institute of Chemical, Environmental
and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
| | - Julia Derx
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
- Institute of Hydraulic
Engineering and Water Resources Management, TU Wien, 1040 Vienna, Austria
| | - Alfred Paul Blaschke
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
- Institute of Hydraulic
Engineering and Water Resources Management, TU Wien, 1040 Vienna, Austria
| | - James E. Ebdon
- Environment
& Public Health Research and Enterprise Group, School of Environment
and Technology, University of Brighton, BN2 4GJ Brighton, U.K.
| | - Rita Linke
- Research
Group Environmental Microbiology and Molecular
Diagnostics 166-5-3, Institute of Chemical, Environmental
and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
| | - Lukas Egle
- Institute for Water Quality
and Resource Management, TU Wien, 1040 Vienna, Austria
| | - Warish Ahmed
- CSIRO
Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia
| | - Anicet R. Blanch
- Department
of Genetics, Microbiology and Statistics, University of Barcelona, 08028 Barcelona, Spain
| | - Denis Byamukama
- Department
of Biochemistry, Makerere University, P.O. Box 27755 Kampala, Uganda
| | - Marion Savill
- Affordable Water Limited, 1011 Auckland, New Zealand
| | - Douglas Mushi
- Department
of Biosciences, Sokoine University of Agriculture, PO BOX 3038, Morogoro, Tanzania
| | - Héctor A. Cristóbal
- Laboratorio
de Aguas y Suelos, Instituto de Investigaciones para la Industria
Química (INIQUI), Consejo Nacional
de Investigaciones Científicas y Técnicas and Universidad
Nacional de Salta, CP 4400 Salta, Argentina
| | - Thomas A. Edge
- Environment and Climate Change Canada, Canada Centre for Inland Waters, Burlington, L7S 1A1, Ontario, Canada
| | | | - Asli Aslan
- Department
of Epidemiology and Environmental Health Sciences, Georgia Southern University, Statesboro, 30460 Georgia, United States
| | - Yolanda M. Brooks
- Department of Fisheries and Wildlife, Michigan State University East Lansing, 48824 Michigan, United States
| | - Regina Sommer
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
- Institute
for Hygiene and Applied Immunology, Water Hygiene, Medical University of Vienna, 1090 Vienna, Austria
| | - Yoshifumi Masago
- New
Industry Creation Hatchery Center, Tohoku
University, 980-8579 Sendai, Japan
| | - Maria I. Sato
- Departamento
de Análises Ambientais, CETESB -
Cia. Ambiental do Estado de São Paulo, 05459-900 São
Paulo, Brasil
| | - Huw D. Taylor
- Environment
& Public Health Research and Enterprise Group, School of Environment
and Technology, University of Brighton, BN2 4GJ Brighton, U.K.
| | - Joan B. Rose
- Department of Fisheries and Wildlife, Michigan State University East Lansing, 48824 Michigan, United States
| | - Stefan Wuertz
- Singapore Centre
for Environmental Life Sciences Engineering and
School of Civil and Environmental Engineering, Nanyang Technological University, 637551 Singapore
| | - Orin C. Shanks
- U.S. Environmental Protection Agency, Office
of Research and Development, 45268 Cincinnati, Ohio, United States
| | | | - Robert L. Mach
- Research Division Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
| | - Domenico Savio
- Division Water Quality and Health, Department Pharmacology, Physiology and Microbiology, Karl Landsteiner University of Health Sciences, 3500 Krems an der Donau, Austria
| | - Matthias Zessner
- Institute for Water Quality
and Resource Management, TU Wien, 1040 Vienna, Austria
| | - Andreas H. Farnleitner
- Research
Group Environmental Microbiology and Molecular
Diagnostics 166-5-3, Institute of Chemical, Environmental
and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
- Interuniversity
Cooperation Centre Water & Health, Vienna, Austria
- Division Water Quality and Health, Department Pharmacology, Physiology and Microbiology, Karl Landsteiner University of Health Sciences, 3500 Krems an der Donau, Austria
- Phone: +43 664 605882244; e-mail:
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49
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Jiang YS, Riedel TE, Popoola JA, Morrow BR, Cai S, Ellington AD, Bhadra S. Portable platform for rapid in-field identification of human fecal pollution in water. WATER RESEARCH 2018; 131:186-195. [PMID: 29278789 PMCID: PMC5999531 DOI: 10.1016/j.watres.2017.12.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 12/06/2017] [Accepted: 12/12/2017] [Indexed: 05/02/2023]
Abstract
Human fecal contamination of water is a public health risk. However, inadequate testing solutions frustrate timely, actionable monitoring. Bacterial culture-based methods are simple but typically cannot distinguish fecal host source. PCR assays can identify host sources but require expertise and infrastructure. To bridge this gap we have developed a field-ready nucleic acid diagnostic platform and rapid sample preparation methods that enable on-site identification of human fecal contamination within 80 min of sampling. Our platform relies on loop-mediated isothermal amplification (LAMP) of human-associated Bacteroides HF183 genetic markers from crude samples. Oligonucleotide strand exchange (OSD) probes reduce false positives by sequence specifically transducing LAMP amplicons into visible fluorescence that can be photographed by unmodified smartphones. Our assay can detect as few as 17 copies/ml of human-associated HF183 targets in sewage-contaminated water without cross-reaction with canine or feline feces. It performs robustly with a variety of environmental water sources and with raw sewage. We have also developed lyophilized assays and inexpensive 3D-printed devices to minimize cost and facilitate field application.
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Affiliation(s)
- Yu Sherry Jiang
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Timothy E Riedel
- Freshman Research Initiative, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jessica A Popoola
- Freshman Research Initiative, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Barrett R Morrow
- Freshman Research Initiative, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Sheng Cai
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Andrew D Ellington
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Sanchita Bhadra
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
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50
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Cao Y, Sivaganesan M, Kelty CA, Wang D, Boehm AB, Griffith JF, Weisberg SB, Shanks OC. A human fecal contamination score for ranking recreational sites using the HF183/BacR287 quantitative real-time PCR method. WATER RESEARCH 2018; 128:148-156. [PMID: 29101858 PMCID: PMC7228037 DOI: 10.1016/j.watres.2017.10.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/25/2017] [Accepted: 10/31/2017] [Indexed: 05/05/2023]
Abstract
Human fecal pollution of recreational waters remains a public health concern worldwide. As a result, there is a growing interest in the application of human-associated fecal source identification quantitative real-time PCR (qPCR) technologies for water quality research and management. However, there are currently no standardized approaches for field implementation and interpretation of qPCR data. In this study, a standardized HF183/BacR287 qPCR method was combined with a water sampling strategy and a novel Bayesian weighted average approach to establish a human fecal contamination score (HFS) that can be used to prioritize sampling sites for remediation based on measured human waste levels. The HFS was then used to investigate 975 study design scenarios utilizing different combinations of sites with varying sampling intensities (daily to once per week) and number of qPCR replicates per sample (2-14 replicates). Findings demonstrate that site prioritization with HFS is feasible and that both sampling intensity and number of qPCR replicates influence reliability of HFS estimates. The novel data analysis strategy presented here provides a prescribed approach for the implementation and interpretation of human-associated HF183/BacR287 qPCR data with the goal of site prioritization based on human fecal pollution levels. In addition, information is provided for future users to customize study designs for optimal HFS performance.
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Affiliation(s)
- Yiping Cao
- Southern California Coastal Water Research Project Authority, Costa Mesa, CA 92626, USA
| | - Mano Sivaganesan
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH 45268, USA
| | - Catherine A Kelty
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH 45268, USA
| | - Dan Wang
- Department of Civil and Environmental Engineering, Stanford University, Stanford CA 94305, USA
| | - Alexandria B Boehm
- Department of Civil and Environmental Engineering, Stanford University, Stanford CA 94305, USA
| | - John F Griffith
- Southern California Coastal Water Research Project Authority, Costa Mesa, CA 92626, USA
| | - Stephen B Weisberg
- Southern California Coastal Water Research Project Authority, Costa Mesa, CA 92626, USA
| | - Orin C Shanks
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH 45268, USA.
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