Automated Targeted Sampling of Waterborne Pathogens and Microbial Source Tracking Markers Using Near-Real Time Monitoring of Microbiological Water Quality

Waterborne pathogens are heterogeneously distributed across various spatiotemporal scales in water resources, and representative sampling is therefore crucial for accurate risk assessment. Since regulatory monitoring of microbiological water quality is usually conducted at fixed time intervals, it can miss short-term fecal contamination episodes and underestimate underlying microbial risks. In the present paper, we developed a new automated sampling methodology based on near real-time measurement of a biochemical indicator of fecal pollution. Online monitoring of β-D-glucuronidase (GLUC) activity was used to trigger an automated sampler during fecal contamination events in a drinking water supply and at an urban beach. Significant increases in protozoan parasites, microbial source tracking markers and E. coli were measured during short-term (<24 h) fecal pollution episodes, emphasizing the intermittent nature of their occurrence in water. Synchronous triggering of the automated sampler with online GLUC activity measurements further revealed a tight association between the biochemical indicator and culturable E. coli. The proposed event sampling methodology is versatile and in addition to the two triggering modes validated here, others can be designed based on specific needs and local settings. In support to regulatory monitoring schemes, it should ultimately help gathering crucial data on waterborne pathogens more efficiently during episodic fecal pollution events.

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Identifying Host Sources of Fecal Pollution: Diversity of Escherichia coli in Confined Dairy and Swine Production Systems

Applied and Environmental Microbiology ◽

10.1128/aem.71.10.5992-5998.2005 ◽

2005 ◽

Vol 71 (10) ◽

pp. 5992-5998 ◽

Cited By ~ 33

Author(s):

Zexun Lu ◽

David Lapen ◽

Andrew Scott ◽

Angela Dang ◽

Edward Topp

Keyword(s):

Escherichia Coli ◽

Dairy Farm ◽

Sampling Strategy ◽

Farming Systems ◽

Microbial Source Tracking ◽

Fecal Pollution ◽

Source Tracking ◽

E Coli ◽

Repetitive Extragenic Palindromic Pcr ◽

Repetitive Extragenic Palindromic

ABSTRACT Repetitive extragenic palindromic PCR fingerprinting of Escherichia coli is one microbial source tracking approach for identifying the host source origin of fecal pollution in aquatic systems. The construction of robust known-source libraries is expensive and requires an informed sampling strategy. In many types of farming systems, waste is stored for several months before being released into the environment. In this study we analyzed, by means of repetitive extragenic palindromic PCR using the enterobacterial repetitive intergenic consensus primers and comparative analysis using the Bionumerics software, collections of E. coli obtained from a dairy farm and from a swine farm, both of which stored their waste as a slurry in holding tanks. In all fecal samples, obtained from either barns or holding tanks, the diversity of the E. coli populations was underrepresented by collections of 500 isolates. In both the dairy and the swine farms, the diversity of the E. coli community was greater in the manure holding tank than in the barn, when they were sampled on the same date. In both farms, a comparison of stored manure samples collected several months apart suggested that the community composition changed substantially in terms of the detected number, absolute identity, and relative abundance of genotypes. Comparison of E. coli populations obtained from 10 different locations in either holding tank suggested that spatial variability in the E. coli community should be accounted for when sampling. Overall, the diversity in E. coli populations in manure slurry storage facilities is significant and likely is problematic with respect to library construction for microbial source tracking applications.

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Norwegian study on microbial source tracking for water quality control and pollution removal in constructed wetland treating catchment run-off

Water Science & Technology ◽

10.2166/wst.2017.303 ◽

2017 ◽

Vol 76 (5) ◽

pp. 1158-1166 ◽

Cited By ~ 10

Author(s):

Lisa Paruch ◽

Adam M. Paruch ◽

Anne-Grete Buseth Blankenberg ◽

Ketil Haarstad ◽

Trond Mæhlum

Keyword(s):

Water Quality ◽

Quality Control ◽

Constructed Wetland ◽

Microbial Source Tracking ◽

Source Tracking ◽

Water Quality Control ◽

Positive Correlation ◽

E Coli ◽

Run Off ◽

Pollution Removal

This study describes the first Norwegian microbial source tracking (MST) approach for water quality control and pollution removal from catchment run-off in a nature-based treatment system (NBTS) with a constructed wetland. The applied MST tools combined microbial analyses and molecular tests to detect and define the source(s) and dominant origin(s) of faecal water contamination. Faecal indicator bacteria Escherichia coli and host-specific Bacteroidales 16 s rRNA gene markers have been employed. The study revealed that the newly developed contribution profiling of faecal origin derived from the Bacteroidales DNA could quantitatively distinguish between human and non-human pollution origins. Further, the outcomes of the MST test have been compared with the results of both physicochemical analyses and tests of pharmaceutical and personal care products (PPCPs). A strong positive correlation was discovered between the human marker and PPCPs. Gabapentin was the most frequently detected compound and it showed the uppermost positive correlation with the human marker. The study demonstrated that the NBTS performs satisfactorily with the removal of E. coli but not PPCPs. Interestingly, the presence of PPCPs in the water samples was not correlated with high concentrations of E. coli. Neither has the latter an apparent correlation with the human marker.

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Evaluating short-term changes in recreational water quality during a hydrograph event using a combination of microbial tracers, environmental microbiology, microbial source tracking and hydrological techniques: A case study in Southwest Wales, UK

Water Research ◽

10.1016/j.watres.2010.06.047 ◽

2010 ◽

Vol 44 (16) ◽

pp. 4783-4795 ◽

Cited By ~ 16

Author(s):

Mark D. Wyer ◽

David Kay ◽

John Watkins ◽

Cheryl Davies ◽

Chris Kay ◽

...

Keyword(s):

Water Quality ◽

Environmental Microbiology ◽

Microbial Source Tracking ◽

Source Tracking ◽

Recreational Water ◽

Short Term ◽

Recreational Water Quality

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Relative Decay of Bacteroidales Microbial Source Tracking Markers and Cultivated Escherichia coli in Freshwater Microcosms

Applied and Environmental Microbiology ◽

10.1128/aem.02636-09 ◽

2010 ◽

Vol 76 (10) ◽

pp. 3255-3262 ◽

Cited By ~ 94

Author(s):

Linda K. Dick ◽

Erin A. Stelzer ◽

Erin E. Bertke ◽

Denise L. Fong ◽

Donald M. Stoeckel

Keyword(s):

Escherichia Coli ◽

Water Quality ◽

Microbial Source Tracking ◽

Decay Rates ◽

Source Tracking ◽

Rrna Gene ◽

Fecal Indicator ◽

Gene Markers ◽

E Coli ◽

Log Reduction

ABSTRACT Fecal indicator bacteria (FIB), commonly used to regulate sanitary water quality, cannot discriminate among sources of contamination. The use of alternative quantitative PCR (qPCR) methods for monitoring fecal contamination or microbial source tracking requires an understanding of relationships with cultivated FIB, as contamination ages under various conditions in the environment. In this study, the decay rates of three Bacteroidales 16S rRNA gene markers (AllBac for general contamination and qHF183 and BacHum for human-associated contamination) were compared with the decay rate of cultivated Escherichia coli in river water microcosms spiked with human wastewater. The following five sets of microcosms were monitored over 11 days: control, artificial sunlight, sediment exposure, reduced temperature, and no autochthonous predation. Decay was characterized by estimation of the time needed to produce a 2-log reduction (t 99). No treatment-associated differences in the decay of the 4 targets were evident except with reduced predation, where E. coli, qHF183, and BacHum markers had lower levels of decay by day 3. However, there were substantial target-associated differences. Decay curves for the AllBac marker indicated a larger persistent population than those of the other targets. Exposure to sunlight, sediment, and reduced predation resulted in more rapid decay of the human-associated markers relative to cultivable E. coli, but there were no differences in t 99 values among the 4 targets under control conditions or at reduced temperatures. Further evaluation of epidemiological relationships will be needed in order to relate the markers directly to health risk. These findings suggest that the tested human-associated markers can complement E. coli as indicators of the human impact on sanitary water quality under the constrained conditions described in this paper.

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The relationship between health effects in triathletes and microbiological quality of freshwater

Water Science & Technology ◽

10.2166/wst.1995.0549 ◽

1995 ◽

Vol 31 (5-6) ◽

pp. 19-26 ◽

Cited By ~ 7

Author(s):

G. J. Medema ◽

I. A. van Asperen ◽

J. M. Klokman-Houweling ◽

A. Nooitgedagt ◽

M. J. W. van de Laar ◽

...

Keyword(s):

Water Quality ◽

Geometric Mean ◽

Microbiological Quality ◽

Quality Parameters ◽

Health Complaints ◽

E Coli ◽

Thermotolerant Coliforms ◽

Microbiological Water Quality ◽

The Relationship ◽

Faecal Streptococci

This pilot study was carried out to determine the relationship between microbiological water quality parameters and the occurrence of health complaints among triathletes. Data were collected at an Olympic distance triathlon (n=314) and a run-bike-run (n=81; controls for exposure to fresh water). At the time of the triathlon, the concentrations of Escherichia coli , thermotolerant coliforms, faecal streptococci, entero- and reoviruses, F-specific RNA phages, Salmonella, Campylobacter, Aeromonas, Plesiomonas shigelloides, Pseudomonas aeruginosa and Staphylococcus aureus were examined over the swimming course. Information on the occurrence of health complaints during the competition and in the week thereafter was collected through a written questionnaire. The results show that triathletes and run-bike-runners are comparable with respect to factors other than water exposure (age, sex, training history, physical stress, lower intestinal health complaints during the competition) that may influence the occurrence of health complaints in the week after the competition. Triathletes and run-bike-runners reported gastro-intestinal (7.7% vs 2.5%), respiratory (5.5% vs 3.7%), skin/mucosal (2.6% vs 1.2%), general (3.5% vs 1.2%) and total symptoms (14.8% vs 7.4%) in the week after the event. The health risks for triathletes for all symptom groups are not significantly higher than for run-bike-runners. The geometric mean concentration of faecal indicator bacteria is relatively low: E. coli 170/100 ml; faecal streptococci 13/100 ml, enteroviruses were present at concentrations of 0.1/l. The group of triathletes was homogeneusly and relatively intensely exposed to water; they all swam in the same body of water at the same time and 75% reported to have swallowed freshwater. It was concluded that this study design is suitable to study the relationship between health complaints and microbiological water quality. In the summers of 1993 and 1994, a study will be carried out concerning several run-bike-runs and triathlons in freshwaters of different quality.

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Flood and rainfall mobilisation of E. coli and faecal source tracking markers from decomposing cowpats

10.5194/egusphere-egu21-3577 ◽

2021 ◽

Author(s):

Megan Devane ◽

Brent Gilpin ◽

Jennifer Webster-Brown ◽

Louise Weaver ◽

Pierre Dupont ◽

...

Keyword(s):

Water Quality ◽

Overland Flow ◽

Quantitative Polymerase Chain Reaction ◽

Linear Regression Analysis ◽

Water Quality Monitoring ◽

Quality Monitoring ◽

Source Tracking ◽

Faecal Contamination ◽

E Coli ◽

Faecal Indicators

The intensification of dairy farming on the agricultural landscape in New Zealand has raised concerns about pollution sources from dairy faecal runoff into waterways. The transport of faecal pollution from farms into waterways is facilitated by overland flow, which can result from rain and flood events, poorly designed irrigation practices and the washing down of milking sheds.An important step for mitigation of pollution is the identification of the source(s) of faecal contamination. When elevated levels of faecal indicator bacteria (FIB) such as Escherichia coli are identified in a waterway, faecal source tracking (FST) tools such as microbial source tracking (MST) using quantitative polymerase chain reaction (qPCR), and faecal steroids (for example, cholesterol) provide information about the sources of faecal contamination. The understanding of the fate (degradation/persistence) and transport of these FST markers in the environment is recognised as an important requirement for the interpretation of water quality monitoring in aquatic environments.This study investigated the effects of faecal decomposition on bovine faecal indicators (E. coli and FST markers: bovine-associated qPCR markers and ten faecal steroids) by monitoring the effect of flood and rainfall events on simulated cowpats over a five and a half month period under field conditions. Two separate spring/summer trials were conducted to evaluate: Trial 1) the mobilisation under simulated flood conditions of the faecal indicators from irrigated versus non-irrigated cowpats, Trial 2) the mobilisation of faecal indicators from non-irrigated cowpat flood runoff versus runoff after simulated rainfall onto non-irrigated cowpats.The microbial community changes within the decomposing cowpat (as illustrated by amplicon-based metagenomic analysis) were expected to impact on the survival/persistence of the bacterial targets of the MST markers, and also alter the ratio between faecal sterols and their biodegradation products, the stanols. It was hypothesised, therefore, that there would be:<ul><li>Changes over time in the concentration of E. coli and the bovine-associated MST markers mobilised into the cowpat runoff</li> <li>Alterations in the FST ratio signature of the ten measured faecal steroids, resulting in a change from a bovine faecal steroid signature in fresh cowpat runoff to other animal faecal signatures in the runoff from decomposing cowpats</li> <li>A difference in the mobilisation decline rates of all FST and microbial markers within a treatment regime and between treatments.</li> </ul>Linear regression analysis was undertaken to establish mobilisation decline rates for each of the analytes in the mobilisable phase from the cowpat runoff treatments, with calculation of the time taken in days for reduction in 90% of the concentration (T90), and statistical comparison of the regression coefficients (slopes) of all analytes. The results will include a discussion of the impacts of the study&#8217;s observations on the interpretation of faecal indicator assessments for water quality monitoring in waterways influenced by sources of faecal contamination.

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Coliforms and other microbial indicators occurrence in water and biofilm in full-scale distribution systems

Water Science & Technology ◽

10.2166/wst.2006.446 ◽

2006 ◽

Vol 54 (3) ◽

pp. 41-48 ◽

Cited By ~ 7

Author(s):

M. Batté ◽

C. Féliers ◽

P. Servais ◽

V. Gauthier ◽

J.-C. Joret ◽

...

Keyword(s):

Water Quality ◽

Residence Time ◽

Distribution Systems ◽

Full Scale ◽

Bacterial Indicators ◽

Total Coliforms ◽

E Coli ◽

Plate Counts ◽

Microbiological Water Quality ◽

Heterotrophic Plate Counts

Biofilm and microbial water quality were studied in four middle size full-scale distribution systems (DS) in France serving 5,000–30,000 inhabitants (maximum residence time 23–160 h) through three sampling campaigns over 1 year. Three of these DSs were chosen because of a quite high occurrence of bacterial indicators (i.e. total coliforms), the last DS was considered as a reference. Biofilm was studied on cast iron coupons incubated for more than 1 month in devices continuously fed with water from the DS in conditions imitating those met in DS. The devices were located at different points (4–6) along each DS. The abundance of bacteria in biofilm was estimated by heterotrophic plate counts (HPC) after detachment of the biofilm from the support by sonication. Microbiological water quality was estimated in parallel; analysis of total coliforms, E. coli, enterococci and anaerobic sulphide-reducing bacteria spores (ASRB spores) was carried out in biofilm and water. Over the period of the study, 171 water samples and 57 biofilm samples were collected. Over these 171 waters, 19 (11%) were positive for at least one of the measured indicators while two biofilm samples were positive (3.5%). Significant differences were observed in the levels of contamination between the DSs. High residence time in the DS, low disinfectant residual and high temperature increased the risk of indicator occurrence in the water phase. Due to the low number of biofilm samples positive for bacterial indicators, the data collected in the present study did not allow observation of a direct association between biofilm and water contaminations, even if the occurrence of indicators in water appeared on DSs with the highest density of biofilm (HPC).

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Evaluation of Bovine Feces-Associated Microbial Source Tracking Markers and Their Correlations with Fecal Indicators and Zoonotic Pathogens in a Brisbane, Australia, Reservoir

Applied and Environmental Microbiology ◽

10.1128/aem.03234-12 ◽

2013 ◽

Vol 79 (8) ◽

pp. 2682-2691 ◽

Cited By ~ 35

Author(s):

W. Ahmed ◽

T. Sritharan ◽

A. Palmer ◽

J. P. S. Sidhu ◽

S. Toze

Keyword(s):

Host Specificity ◽

Water Samples ◽

Microbial Source Tracking ◽

Fecal Pollution ◽

Decay Rates ◽

Source Tracking ◽

Content Type ◽

Zoonotic Pathogens ◽

Maximum Value ◽

Bovine Feces

ABSTRACTThis study was aimed at evaluating the host specificity and host sensitivity of two bovine feces-associated bacterial (BacCow-UCD and cowM3) and one viral [bovine adenovirus (B-AVs)] microbial source tracking (MST) markers by screening 130 fecal and wastewater samples from 10 target and nontarget host groups in southeast Queensland, Australia. In addition, 36 water samples were collected from a reservoir and tested for the occurrence of all three bovine feces-associated markers along with fecal indicator bacteria (FIB),Campylobacterspp.,Escherichia coliO157, andSalmonellaspp. The overall host specificity values of the BacCow-UCD, cowM3, and B-AVs markers to differentiate between bovine and other nontarget host groups were 0.66, 0.88, and 1.00, respectively (maximum value of 1.00). The overall host sensitivity values of these markers, however, in composite bovine wastewater and individual bovine fecal DNA samples were 0.93, 0.90, and 0.60, respectively (maximum value of 1.00). Among the 36 water samples tested, 56%, 22%, and 6% samples were PCR positive for the BacCow-UCD, cowM3, and B-AVs markers, respectively. Among the 36 samples tested, 50% and 14% samples were PCR positive for theCampylobacter16S rRNA andE. coliO157rfbEgenes, respectively. Based on the results, we recommend that multiple bovine feces-associated markers be used if possible for bovine fecal pollution tracking. Nonetheless, the presence of the multiple bovine feces-associated markers along with the presence of potential zoonotic pathogens indicates bovine fecal pollution in the reservoir water samples. Further research is required to understand the decay rates of these markers in relation to FIB and zoonotic pathogens.

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Occurrence of antibiotic resistance inEscherichia colifrom surface waters and fecal pollution sources near Hamilton, Ontario

Canadian Journal of Microbiology ◽

10.1139/w05-028 ◽

2005 ◽

Vol 51 (6) ◽

pp. 501-505 ◽

Cited By ~ 64

Author(s):

Thomas A Edge ◽

Stephen Hill

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Surface Waters ◽

Municipal Wastewater ◽

Average Rate ◽

Fecal Pollution ◽

Pollution Sources ◽

Source Tracking ◽

E Coli ◽

Bird Feces

Antibiotic resistance was examined in 462 Escherichia coli isolates from surface waters and fecal pollution sources around Hamilton, Ontario. Escherichia coli were resistant to the highest concentrations of each of the 14 antibiotics studied, although the prevalence of high resistance was mostly low. Two of 12 E. coli isolates from sewage in a CSO tank had multiple resistance to ampicillin, ciprofloxacin, gentamicin, and tetracycline above their clinical breakpoints. Antibiotic resistance was less prevalent in E. coli from bird feces than from municipal wastewater sources. A discriminant function calculated from antibiotic resistance data provided an average rate of correct classification of 68% for discriminating E. coli from bird and wastewater fecal pollution sources. The preliminary microbial source tracking results suggest that, at times, bird feces might be a more prominent contributor of E. coli to Bayfront Park beach waters than municipal wastewater sources.Key words: antibiotic resistance, Escherichia coli, surface water, fecal pollution.

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