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1. A review on microbial contaminants in stormwater runoff and outfalls: Potential health risks and mitigation strategies

Author:
Ahmed, Warish,   et al.   ; Hamilton, Kerry; Toze, Simon; Cook, Stephen; Page, Declan;     Show all 5 Authors
Source:
The Science of the total environment 2019 v.692 pp. 1304-1321
ISSN:
0048-9697
Subject:
best management practices; climate change; energy; genetic markers; groundwater; industry; microbial contamination; microbiological risk assessment; models; pathogens; public health; rain; risk; risk management; sewage treatment; stormwater; trade; urbanization; water reuse; water supply
Abstract:
... Demands on global water supplies are increasing in response to the need to provide more food, water, and energy for a rapidly growing population. These water stressors are exacerbated by climate change, as well as the growth and urbanisation of industry and commerce. Consequently, urban water authorities around the globe are exploring alternative water sources to meet ever-increasing demands. Thes ...
DOI:
10.1016/j.scitotenv.2019.07.055

2. Use of Escherichia coli genes associated with human sewage to track fecal contamination source in subtropical waters

Author:
Ahmed, Warish,   et al.   ; Senkbeil, Jacob K.; Conrad, James; Harwood, Valerie J.;     Show all 4 Authors
Source:
The Science of the total environment 2019 v.686 pp. 1069-1075
ISSN:
0048-9697
Subject:
Bacteroides; Escherichia coli; genes; genetic markers; human health; microorganisms; quantitative polymerase chain reaction; risk; risk assessment; sewage; total maximum daily load; wastewater; water quality; Florida
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 ge ...
DOI:
10.1016/j.scitotenv.2019.05.201

3. A duplex PCR assay for the simultaneous quantification of Bacteroides HF183 and crAssphage CPQ_056 marker genes in untreated sewage and stormwater

Author:
Ahmed, Warish,   et al.   ; Payyappat, Sudhi; Cassidy, Michele; Besley, Colin;     Show all 4 Authors
Source:
Environment international 2019 v.126 pp. 252-259
ISSN:
0160-4120
Subject:
Bacteroides; DNA; bacteriophages; genes; genetic markers; lakes; monitoring; pollution; quantitative polymerase chain reaction; ribosomal RNA; sewage; stormwater; wastewater
Abstract:
... The HF183 marker gene, derived from the 16S rRNA gene of Bacteroides dorei, has been widely used to identify sewage pollution in environmental waters. CrAssphages are recently discovered DNA bacteriophages that are highly abundant in untreated sewage and have shown promises for tracking sewage contamination in environmental waters. In this paper, we report the development of a duplex quantitative ...
DOI:
10.1016/j.envint.2019.01.035

4. Marker genes of fecal indicator bacteria and potential pathogens in animal feces in subtropical catchments

Author:
Ahmed, Warish,   et al.   ; O'Dea, Christian; Masters, Nicole; Kuballa, Anna; Marinoni, Oswald; Katouli, Mohammad;     Show all 6 Authors
Source:
The Science of the total environment 2019 v.656 pp. 1427-1435
ISSN:
0048-9697
Subject:
Campylobacter; Cryptosporidium parvum; Enterococcus; Escherichia coli; Giardia lamblia; Macropus giganteus; Mycobacterium avium complex; Pteropodidae; Salmonella; cattle; chickens; dogs; feces; genetic markers; humans; indicator species; pathogens; quantitative polymerase chain reaction; risk assessment; swine; watersheds; wild animals
Abstract:
... We investigated the abundance of marker genes of two fecal indicator bacteria (FIB) and eight potential pathogens in fecal samples of humans (n = 14) and 10 domestic and native wild animals (n = 134). For each target animal, between 10 and 14 individual fecal samples were collected (n = 148 individual fecal samples in total). The abundance of FIB and potential pathogens within each sample was dete ...
DOI:
10.1016/j.scitotenv.2018.11.439

5. Comparative decay of sewage-associated marker genes in beach water and sediment in a subtropical region

Author:
Ahmed, Warish,   et al.   ; Zhang, Qian; Kozak, Sonya; Beale, David; Gyawali, Pradip; Sadowsky, Michael J.; Simpson, Stuart;     Show all 7 Authors
Source:
Water research 2019 v.149 pp. 511-521
ISSN:
0043-1354
Subject:
Adenoviridae; Bacteroides; Enterococcus; Escherichia coli; Polyomaviridae; bacteriophages; feces; genes; genetic markers; humans; models; quantitative polymerase chain reaction; ribosomal RNA; risk assessment; sediments; subtropics; surface water; uncertainty; water quality
Abstract:
... There is a growing move towards using the quantitative polymerase chain (qPCR)-based sewage-associated marker genes to assess surface water quality. However, a lack of understanding about the persistence of many sewage-associated markers creates uncertainty for those tasked with investigating microbial water quality. In this study, we investigated the decay of two qPCR FIB [E. coli (EC), and Enter ...
DOI:
10.1016/j.watres.2018.10.088

6. Synergy between quantitative microbial source tracking (qMST) and quantitative microbial risk assessment (QMRA): A review and prospectus

Author:
Ahmed, Warish,   et al.   ; Zhang, Qian; Gallard, Javier; Wu, Baolei; Harwood, Valerie J.; Sadowsky, Michael J.; Hamilton, Kerry A.;     Show all 7 Authors
Source:
Environment international 2019 v.130 pp. 104703
ISSN:
0160-4120
Subject:
environmental factors; genetic markers; host specificity; indicator species; microbiological risk assessment; microorganisms; models; monitoring; nucleic acids; pathogens; primary contact; risk; risk management; surface water
Abstract:
... The use of microbial source tracking (MST) marker genes has grown in recent years due to the need to attribute point and non-point fecal contamination to specific sources. Quantitative microbial risk assessment (QMRA) is a modeling approach used to estimate health risks from exposure to feces-contaminated water and associated pathogens. A combination of these approaches [quantitative MST (qMST) an ...
DOI:
10.1016/j.envint.2019.03.051

7. Novel crAssphage marker genes ascertain sewage pollution in a recreational lake receiving urban stormwater runoff

Author:
Ahmed, Warish,   et al.   ; Payyappat, Sudhi; Cassidy, Michele; Besley, Colin; Power, Kaye;     Show all 5 Authors
Source:
Water research 2018 v.145 pp. 769-778
ISSN:
0043-1354
Subject:
DNA; bacteriophages; cattle; cross reaction; feces; genetic markers; host specificity; humans; lakes; pollution; quantitative polymerase chain reaction; sewage; storms; stormwater; wastewater; watersheds; New South Wales
Abstract:
... Considerable efforts have been made in recent years in developing novel marker genes for fecal pollution tracking in environmental waters. CrAssphage are recently discovered DNA bacteriophage that are highly abundant in human feces and untreated sewage. In this study, we evaluated the host-sensitivity and -specificity of the newly designed crAssphage qPCR assays (Stachler et al., 2017) CPQ_056 and ...
DOI:
10.1016/j.watres.2018.08.049

8. Precipitation influences pathogenic bacteria and antibiotic resistance gene abundance in storm drain outfalls in coastal sub-tropical waters

Author:
Ahmed, Warish,   et al.   ; Zhang, Qian; Lobos, Aldo; Senkbeil, Jacob; Sadowsky, Michael J.; Harwood, Valerie J.; Saeidi, Nazanin; Marinoni, Oswald; Ishii, Satoshi;     Show all 9 Authors
Source:
Environment international 2018 v.116 pp. 308-318
ISSN:
0160-4120
Subject:
Bacteroides; Enterococcus; Escherichia coli; antibiotic resistance genes; aquatic ecosystems; bacteria; carbapenems; genetic markers; humans; indicator species; infrastructure; intimin; microbial contamination; pathogens; quantitative polymerase chain reaction; sewage; storms; stormwater; virulence; viruses; Florida
Abstract:
... Stormwater contamination can threaten the health of aquatic ecosystems and human exposed to runoff via nutrient and pathogen influxes. In this study, the concentrations of 11 bacterial pathogens and 47 antibiotic resistance genes (ARGs) were determined by using high-throughput microfluidic qPCR (MFQPCR) in several storm drain outfalls (SDOs) during dry and wet weather in Tampa Bay, Florida, USA. D ...
DOI:
10.1016/j.envint.2018.04.005

9. Current Status of Marker Genes of <em>Bacteroides</em> and Related Taxa for Identifying Sewage Pollution in Environmental Waters

Author:
Ahmed, Warish,   et al.   ; Hughes, Bridie; Harwood, Valerie J.;     Show all 3 Authors
Source:
Water 2016 v.8 no.6
ISSN:
2073-4441
Subject:
Bacteroides; DNA; bacteria; environmental health; feces; gastrointestinal system; genes; genetic markers; host specificity; human health; microarray technology; pollution; quantitative polymerase chain reaction; ribosomal RNA; sewage; tracer techniques
Abstract:
... Microbial source tracking (MST) endeavors to determine sources of fecal pollution in environmental waters by capitalizing on the association of certain microorganisms with the gastrointestinal tract and feces of specific animal groups. Several decades of research have shown that bacteria belonging to the gut-associated order Bacteroidales, and particularly the genus Bacteroides, tend to co-evolve ...
DOI:
10.3390/w8060231

10. Global Distribution of Human-Associated Fecal Genetic Markers in Reference Samples from Six Continents

Author:
Ahmed, Warish,   et al.   ; Mayer, René E.; Reischer, Georg H.; Ixenmaier, Simone K.; Derx, Julia; Blaschke, Alfred Paul; Ebdon, James E.; Linke, Rita; Egle, Lukas; Blanch, Anicet R.; Byamukama, Denis; Savill, Marion; Mushi, Douglas; Cristóbal, Héctor A.; Edge, Thomas A.; Schade, Margit A.; Aslan, Asli; Brooks, Yolanda M.; Sommer, Regina; Masago, Yoshifumi; Sato, Maria I.; Taylor, Huw D.; Rose, Joan B.; Wuertz, Stefan; Shanks, Orin C.; Piringer, Harald; Mach, Robert L.; Savio, Domenico; Zessner, Matthias; Farnleitner, Andreas H.;     Show all 30 Authors
Source:
Environmental science & technology 2018 v.52 no.9 pp. 5076-5084
ISSN:
1520-5851
Subject:
feces; genetic markers; geographical distribution; health effects assessments; humans; models; monitoring; municipal wastewater; pollution; wastewater treatment; water quality; wild animals
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 mar ...
DOI:
10.1021/acs.est.7b04438