Articoli di riviste: "Faecal contamination"

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Amoroso, Caroline R., Alexa G. Frink e Charles L. Nunn. "Water choice as a counterstrategy to faecally transmitted disease: an experimental study in captive lemurs". Behaviour 154, n. 13-15 (2017): 1239–58. http://dx.doi.org/10.1163/1568539x-00003466.

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Abstract Many parasites and pathogens are transmitted via water, including through faecal contamination of water sources. Yet water is essential for survival, and some species gain nutritional and other benefits from coprophagy. We investigated how primates balance the risks of faecal pathogen transmission with potential benefits of faeces ingestion in their selection of water sources by conducting behavioural experiments with five species of lemurs (Family Lemuridae) in captivity. Subjects were given a choice between clean water and water ‘contaminated’ with disinfected faecal material, which contained cues associated with faecally transmitted parasites, but minimal risk. We found that lemurs exhibited strong preferences for the clean water. This pattern was supported even at low levels of faecal contamination and in species adapted to water-limited habitats, for which choosiness about water quality could present a dehydration risk. Our results strongly support the hypothesis that avoiding faecal contamination is important in water selection.

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Godfree, A. F., D. Kay e M. D. Wyer. "Faecal streptococci as indicators of faecal contamination in water". Journal of Applied Microbiology 83, S1 (ottobre 1997): 110–19. http://dx.doi.org/10.1046/j.1365-2672.83.s1.12.x.

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Leeming, Rhys, Jonathan S. Stark e James J. Smith. "Novel use of faecal sterols to assess human faecal contamination in Antarctica: a likelihood assessment matrix for environmental monitoring". Antarctic Science 27, n. 1 (25 giugno 2014): 31–43. http://dx.doi.org/10.1017/s0954102014000273.

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AbstractWastewater containing human sewage is often discharged with little or no treatment into the Antarctic marine environment. Faecal sterols (primarily coprostanol) in sediments have been used for assessment of human sewage contamination in this environment, butin situproduction and indigenous faunal inputs can confound such determinations. Using gas chromatography with mass spectral detection profiles of both C27and C29sterols, potential sources of faecal sterols were examined in nearshore marine sediments, encompassing sites proximal and distal to the wastewater outfall at Davis Station. Faeces from indigenous seals and penguins were also examined. Faeces from several indigenous species contained significant quantities of coprostanol but not 24-ethylcoprostanol, which is present in human faeces.In situcoprostanol and 24-ethylcoprostanol production was identified by co-production of their respectiveepi-isomers at sites remote from the wastewater source and in high total organic matter sediments. A C29sterols-based polyphasic likelihood assessment matrix for human sewage contamination is presented, which distinguishes human from local fauna faecal inputs andin situproduction in the Antarctic environment. Sewage contamination was detected up to 1.5 km from Davis Station.

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Baudišová, D. "Microbial pollution of water from agriculture". Plant, Soil and Environment 55, No. 10 (21 ottobre 2009): 429–35. http://dx.doi.org/10.17221/131/2009-pse.

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Microbial contamination of small streams in agricultural areas was monitored for two years. Microbiological indicators of faecal pollution (faecal coliforms, Escherichia coli and intestinal enterococci were detected by standard methods based on the cultivation of bacteria on selective media). The obtained results showed that running contamination of streams from agricultural areas was not extremely high, but it showed marked seasonal fluctuations (the average values and maximal values revealed great differences). Microbial contamination also increased several times in relation to high precipitation. The water quality in three (and/or four) localities exceeded the acceptable counts of faecal coliforms and enterococci given by the Czech legislation (40 CFU/ml for faecal coliforms and 20 CFU/ ml for enterococci). In agriculturally polluted streams, there were detected more enterococci than faecal coliforms, and also some less frequent species related to farm animals (Streptococcus equines and S. bovis) or plant rests (E. mundtii, E. gallinarum, E. casseliflavus) were present. E. faecalis and E. faecium strains (these are the most common species related to human faecal pollution) were less frequent there.

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Leeming, R., N. Bate, R. Hewlett e P. D. Nichols. "Discriminating faecal pollution: a case study of stormwater entering Port Phillip Bay, Australia". Water Science and Technology 38, n. 10 (1 novembre 1998): 15–22. http://dx.doi.org/10.2166/wst.1998.0369.

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This investigation was designed to provide preliminary information to the Environment Protection Authority concerning the input of faecal matter to stormwater drains in the Rippleside area of Geelong, Victoria. Results derived from the combined use of sterol biomarkers (e.g. coprostanol and 24-ethylcoprostanol) and four sub-groups of bacterial indicators (e.g. thermotolerant coliforms, E. coli, faecal streptococci and enterococci) indicated that during wet weather, all sites sampled were affected by significant human faecal contamination. Ratios of coprostanol to bacterial indicators were similar to those for samples collected from nearby sewer mains. During dry weather, there were still severely elevated levels of faecal contamination based on bacterial indicators, but correspondingly low concentrations of faecal sterols suggesting minimal human or herbivore faecal contamination. The origin of the majority of the faecal pollution in dry weather therefore remains to be fully explained. It is clear from this and related studies that the combined measurement of faecal sterols and bacterial indicators can greatly assist distinguishing sources of faecal pollution. It is also shown for aquatic environments that the measurement of coprostanol or other single indicators alone, is inadequate to fully discern faecal contamination from human sources.

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Wicki, Melanie, Adrian Auckenthaler, Richard Felleisen, Marcel Tanner e Andreas Baumgartner. "Novel Bacteroides host strains for detection of human- and animal-specific bacteriophages in water". Journal of Water and Health 9, n. 1 (3 febbraio 2011): 159–68. http://dx.doi.org/10.2166/wh.2010.165.

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Bacteriophages active against specific Bacteroides host strains were shown to be suitable for detection of human faecal pollution. However, the practical application of this finding is limited because some specific host strains were restricted to certain geographic regions. In this study, novel Bacteroides host strains were isolated that discriminate human and animal faecal pollution in Switzerland. Two strains specific for bacteriophages present in human faecal contamination and three strains specific for bacteriophages indicating animal faecal contamination were evaluated. Bacteriophages infecting human strains were exclusively found in human wastewater, whereas animal strains detected bacteriophages only in animal waste. The newly isolated host strains could be used to determine the source of surface and spring water faecal contamination in field situations. Applying the newly isolated host Bacteroides thetaiotaomicron ARABA 84 for detection of bacteriophages allowed the detection of human faecal contamination in spring water.

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Höglund, C., T. A. Stenström, H. Jönsson e A. Sundin. "Evaluation of faecal contamination and microbial die-off in urine separating sewage systems". Water Science and Technology 38, n. 6 (1 settembre 1998): 17–25. http://dx.doi.org/10.2166/wst.1998.0232.

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An important feature for recirculated products from a sewage system is that the risk for transmission of disease is low. In a urine source separating system faeces may contaminate the collected urine through the toilet. The concentrations of faecal indicator organisms were measured in 14 urine collection tanks. The survival of these and some pathogenic microorganisms in source separated human urine was studied. Total coliforms, E. coli and clostridia were found in low concentrations while faecal streptococci occurred in concentrations up to 105/ml urine solution. The results from phenotyping of faecal streptococci and the high counts indicate growth within the system. The majority of the pathogenic microorganisms investigated had a rapid die-off. A higher temperature, a low degree of dilution and a pH far from neutral had a negative effect on survival. E. coli had a rapid die-off and is not suitable for indicating faecal contamination of the collected urine. Quantification of faecal sterols is a possible alternative to microbial analysis for this purpose. The amounts of coprostanol showed that the faecal contamination varied from not detected to up to 13.3 mg/ml urine solution with a concentration in the urine sludge of up to 417.5 mg/kg.

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van Lieverloo, J. Hein M., E. J. Mirjam Blokker e Gertjan Medema. "Quantitative microbial risk assessment of distributed drinking water using faecal indicator incidence and concentrations". Journal of Water and Health 5, S1 (1 settembre 2007): 131–49. http://dx.doi.org/10.2166/wh.2007.134.

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Quantitative Microbial Risk Assessments (QMRA) have focused on drinking water system components upstream of distribution to customers, for nominal and event conditions. Yet some 15—33% of waterborne outbreaks are reported to be caused by contamination events in distribution systems. In the majority of these cases and probably in all non-outbreak contamination events, no pathogen concentration data was available. Faecal contamination events are usually detected or confirmed by the presence of E.coli or other faecal indicators, although the absence of this indicator is no guarantee of the absence of faecal pathogens. In this paper, the incidence and concentrations of various coliforms and sources of faecal contamination were used to estimate the possible concentrations of faecal pathogens and consequently the infection risks to consumers in event-affected areas. The results indicate that the infection risks may be very high, especially from Campylobacter and enteroviruses, but also that the uncertainties are very high. The high variability of pathogen to thermotolerant coliform ratios estimated in environmental samples severely limits the applicability of the approach described. Importantly, the highest ratios of enteroviruses to thermotolerant coliform were suggested from soil and shallow groundwaters, the most likely sources of faecal contamination that are detected in distribution systems. Epidemiological evaluations of non-outbreak faecal contamination of drinking water distribution systems and thorough tracking and characterisation of the contamination sources are necessary to assess the actual risks of these events.

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Geary, P. M., C. A. Evans, M. T. Maswabi, C. CC Lee, A. Zammit, G. Webster e M. Hunter. "Monitoring and tracking contaminant sources in catchments and estuaries". Water Practice and Technology 10, n. 3 (1 settembre 2015): 601–8. http://dx.doi.org/10.2166/wpt.2015.070.

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In managing water quality in catchments and estuaries, faecal contamination is typically assessed using microbial indicators, such as faecal coliform bacteria. Bacteriological indicators however cannot be used to distinguish whether the faecal contamination has been derived from human or animal sources. The ability to track contamination and distinguish between sources is particularly important where water is used for potable supply, recreational purposes and where commercial aquaculture for human consumption is undertaken. Various chemicals associated with human metabolism and activities which are present in faecal material (such as faecal sterol, pharmaceutical and fluorescent whitening compounds present in wastewaters) can be utilized to identify a human signal and therefore whether the faecal contamination in water is likely to have been derived from human sources. This paper demonstrates an approach and methodology for future work using a combination of these methods to distinguish human contaminant sources in stormwater runoff in an estuary where aquaculture is practised.

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Alexander, L. M., e A. Heaven. "Contamination of urine and faecal specimens." BMJ 306, n. 6883 (10 aprile 1993): 998. http://dx.doi.org/10.1136/bmj.306.6883.998.

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Wicki, Melanie, Adrian Auckenthaler, Richard Felleisen, Fatma Karabulut, Isabel Niederhauser, Marcel Tanner e Andreas Baumgartner. "Assessment of source tracking methods for application in spring water". Journal of Water and Health 13, n. 2 (4 dicembre 2014): 473–88. http://dx.doi.org/10.2166/wh.2014.255.

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For discriminating between human and animal faecal contamination in water, microbial source tracking (MST) approaches using different indicators have been employed. In the current study, a range of 10 such MST indicators described in the scientific literature were comparatively assessed. Bacteriophages infecting host strains of Bacteroides (GA-17, GB-124 and ARABA 84) as well as sorbitol-fermenting bifidobacteria proved useful for indicating human faecal contamination while Rhodococcus coprophilus was associated with animal-derived faecal contamination. These potential source indicators were present in samples of faecal origin, i.e. either in human wastewater or animal waste, from many different regions in Switzerland and therefore showed a geographic stability. In addition, the MST indicators were abundant in surface water and were even sensitive enough to detect faecal contamination in spring water from two study areas in Switzerland. This is the first study that has compared and successfully applied MST methods in spring water.

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Sokolova, Ekaterina, Johan Åström, Thomas J. R. Pettersson, Olof Bergstedt e Malte Hermansson. "Estimation of pathogen concentrations in a drinking water source using hydrodynamic modelling and microbial source tracking". Journal of Water and Health 10, n. 3 (6 giugno 2012): 358–70. http://dx.doi.org/10.2166/wh.2012.183.

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The faecal contamination of drinking water sources can lead to waterborne disease outbreaks. To estimate a potential risk for waterborne infections caused by faecal contamination of drinking water sources, knowledge of the pathogen concentrations in raw water is required. We suggest a novel approach to estimate pathogen concentrations in a drinking water source by using microbial source tracking data and fate and transport modelling. First, the pathogen (norovirus, Cryptosporidium, Escherichia coli O157/H7) concentrations in faecal contamination sources around the drinking water source Lake Rådasjön in Sweden were estimated for endemic and epidemic conditions using measured concentrations of faecal indicators (E. coli and Bacteroidales genetic markers). Afterwards, the fate and transport of pathogens within the lake were simulated using a three-dimensional coupled hydrodynamic and microbiological model. This approach provided information on the contribution from different contamination sources to the pathogen concentrations at the water intake of a drinking water treatment plant. This approach addresses the limitations of monitoring and provides data for quantitative microbial risk assessment (QMRA) and risk management in the context of faecal contamination of surface drinking water sources.

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Betancourt, W. Q., e R. S. Fujioka. "Bacteroides spp. as reliable marker of sewage contamination in Hawaii's environmental waters using molecular techniques". Water Science and Technology 54, n. 3 (1 agosto 2006): 101–7. http://dx.doi.org/10.2166/wst.2006.455.

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Standard PCR (SPCR) and quantitative PCR (QPCR) assays using primers for general and for human-specific Bacteroides 16S rRNA markers were selected as the molecular tests to assess sewage contamination in recreational waters of Hawaii and these same water samples were assayed for culturable concentrations of selected faecal microbial indicators. The results of this study showed that the general primer for Bacteroides was not useful because ambient and polluted water samples were positive for this marker. However, use of human-specific primers reliably detected sewage contamination. The human-specific Bacteroides detection data supported previously reported conclusions that concentrations of alternative faecal indicators (C. perfringens, FRNA coliphages) but not traditional faecal indicators (faecal coliform, E. coli, enterococci) are reliable indicators of faecal contamination in Hawaii's environmental waters. The QPCR assay for the human-specific Bacteroides 16S rRNA marker was faster, more sensitive and more reliable than comparable SPCR assay because QPCR assay provided additional information such as melting temperatures, which confirmed that the right amplicons were being measured and Ct values, which indicated the relative level of faecal contamination.

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Romaniello, Roberto, Giorgio Peri e Alessandro Leone. "Fluorescence hyper-spectral imaging to detecting faecal contamination on fresh tomatoes". Journal of Agricultural Engineering 47, n. 1 (8 marzo 2016): 7. http://dx.doi.org/10.4081/jae.2016.491.

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Faecal contamination of fresh fruits represents a severe danger for human health. Thus some techniques based on microbiological testing were developed to individuate faecal contaminants but those tests do not results efficient because their non-applicability on overall vegetable unity. In this work a methodology based on hyper-spectral fluorescence imaging was developed and tested to detecting faecal contamination on fresh tomatoes. Two image-processing methods were performed to maximise the contrast between the faecal contaminant and tomatoes skin: principal component analysis and band image ratio (BRI). The BRI method allows classifying correctly 70% of contaminated area, with no false-positives in all examined cases. Thus, the developed methodology can be employed for a fast and effective detection of faecal contamination on fresh tomatoes.

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Geary, P. M., e C. M. Davies. "Bacterial source tracking and shellfish contamination in a coastal catchment". Water Science and Technology 47, n. 7-8 (1 aprile 2003): 95–100. http://dx.doi.org/10.2166/wst.2003.0676.

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Introduced pathogens from faecal material can make their way into the aquatic environment from a number of catchment sources. These sources typically include sewage outfalls, seepage from septic tanks, and urban and agricultural runoff. Shellfish as filter feeders are particularly susceptible to contamination in faecally contaminated waters and a range of microbiological indicators have been developed to assess the levels of contamination and likely risks to public health (Hackney and Pierson, 1994). This paper outlines the application of bacterial source tracking (BST) in a shellfish growing area in part of the Port Stephens estuary along the NSW north coast. The approach is based on the premise that bacterial isolates from different faecal sources will have significantly different resistance patterns to the battery of antibiotics and concentrations tested. Faecal streptococci (FS) were isolated from several possible faecal sources: beef and dairy cattle, chickens and humans. The resistance patterns of these isolates to four different concentrations of four antibiotics were compared to those of FS isolates obtained from samples collected upstream and in the vicinity of the oyster leases. Discriminant analysis was performed using the patterns from the known source isolates and the rate of correct classification was determined for each source. The predictive function of discriminant analysis was then used to determine the most probable source of each of the unknown isolates from Tilligerry Creek, the drainage channels to the estuary, and the shellfish leases. Preliminary results are presented here and suggest that there is no single significant source of faecal contamination, rather there are contributions from a range of sources. The findings may have implications for the ways in which land use activities and catchments are managed in similar estuarine locations with a shellfish industry.

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MARION, G., L. A. SMITH, D. L. SWAIN, R. S. DAVIDSON e M. R. HUTCHINGS. "Agent-based modelling of foraging behaviour: the impact of spatial heterogeneity on disease risks from faeces in grazing systems". Journal of Agricultural Science 146, n. 5 (9 settembre 2008): 507–20. http://dx.doi.org/10.1017/s0021859608008022.

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SUMMARYMany of the most pervasive disease challenges to livestock are transmitted via oral contact with faeces (or by faecal–aerosol) and the current paper focuses on how disease risk may depend on: spatial heterogeneity, animal searching behaviour, different grazing systems and faecal deposition patterns including those representative of livestock and a range of wildlife. A spatially explicit agent-based model was developed to describe the impact of empirically observed foraging and avoidance behaviours on the risk of disease presented by investigative and grazing contact with both livestock and wildlife faeces. To highlight the role of spatial heterogeneity on disease risks an analogous deterministic model, which ignores spatial heterogeneity and searching behaviour, was compared with the spatially explicit agent-based model. The models were applied to assess disease risks in temperate grazing systems. The results suggest that spatial heterogeneity is crucial in defining the disease risks to which individuals are exposed even at relatively small scales. Interestingly, however, although sensitive to other aspects of behaviour such as faecal avoidance, it was observed that disease risk is insensitive to search distance for typical domestic livestock restricted to small field plots. In contrast disease risk is highly sensitive to distributions of faecal contamination, in that contacts with highly clumped distributions of wildlife contamination are rare in comparison to those with more dispersed contamination. Finally it is argued that the model is a suitable framework to study the relative inter- and intra-specific disease risks posed to livestock under different realistic management regimes.

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Edge, T. A., S. Hill, G. Stinson, P. Seto e J. Marsalek. "Experience with the antibiotic resistance analysis and DNA fingerprinting in tracking faecal pollution at two lake beaches". Water Science and Technology 56, n. 11 (1 dicembre 2007): 51–58. http://dx.doi.org/10.2166/wst.2007.757.

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Posting or closing of swimming beaches because of faecal contamination is a widespread problem reported in many locations. In a risk-based approach to this problem, the risk to swimmers' health is assessed by field monitoring of indicator bacteria and the associated risks are managed by source controls and other remedial measures. In risk assessment, great advances have been made in recent years with the introduction of microbial source tracking (MST) techniques. Two such techniques, antibiotic resistance analysis and DNA fingerprinting, were applied in a study of causes of faecal contamination at two lake beaches in Toronto, Ontario. Both methods identified bird faeces as the dominant sources of E. coli. Coping with this type of pollution presents a major environmental challenge.

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Gray, Jessica, Nicole Masters, Aaron Wiegand e Mohammad Katouli. "Field assessment of horse-associated genetic markers HoF597 and mtCytb for detecting the source of contamination in surface waters". Canadian Journal of Microbiology 66, n. 11 (novembre 2020): 623–30. http://dx.doi.org/10.1139/cjm-2019-0499.

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We investigated the specificity and sensitivity of two horse-associated markers, HoF597 and Horse mtCytb, and 12 mitochondrial and bacterial markers of six animal species (human, cow, pig, bird, dog, chicken) in the faecal samples of 50 individual horses. Both horse markers were detected in 48 (96%) faecal samples. Cross-reactivity with dog (BacCan545) and pig (P23-2) occurred in 88% and 72% of horse faecal samples, respectively. Several other bacterial and mitochondrial markers of non-target hosts were also detected; however, their specificities were >80%. Analyses of samples from surface waters (n = 11) on or adjacent to properties from which horse faecal samples had been collected showed only the presence of HoF597 but not horse mitochondrial marker. Our data suggest that while bacterial and (or) mitochondrial markers of other animal species may be present in horse faeces, dog and pig markers may predominantly be present in horse faecal samples, which points to their nonspecificity as markers for microbial source tracking. Although HoF597 and Horse mtCytb are highly sensitive and specific for the detection of horse faecal pollution, because of their low numbers, mitochondrial (mtDNA) markers may not be robust for screening surface waters.

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Sobsey, M. D., R. Perdue, M. Overton e J. Fisher. "Factors influencing faecal contamination in coastal marinas". Water Science and Technology 47, n. 3 (1 febbraio 2003): 199–204. http://dx.doi.org/10.2166/wst.2003.0195.

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Recreational pleasure and fishing boats are potential sources of human faecal contamination because the sanitary wastes from boat occupants may be discharged into the surrounding water. The impacts of such faecal contamination from boats is potentially high in marinas where boats are often kept and occupied for varying periods of time. The nature and extent of such faecal contamination from boats in marinas of different design and use is still inadequately understood. In this study the levels of faecal coliform (FC) bacteria were measured in the waters of a confined and an open water marina over a 6 d period encompassing a holiday weekend. Levels of FC rose with increasing occupancy by boats and boaters during the study period and then declined again. FC levels were higher in waters of a confined or basin marina than in waters of an open or unconfined marina. In both confined and open water marinas, FC levels were highest in water samples collected near boats but they also became elevated on occasion in water samples taken a distance of 305 m from boats. Concentrations of FC in marina waters exceeded the standards and guidelines for shell-fishing and primary contact recreation waters. Therefore, greater consideration of human health risks from enteric microbes in marina waters and shellfish is recommended.

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Vaz da Costa-Vargas, S. M., D. D. Mara e C. E. Vargas-Lopez. "Residual Faecal Contamination on Effluent-Irrigated Lettuces". Water Science and Technology 24, n. 9 (1 novembre 1991): 89–94. http://dx.doi.org/10.2166/wst.1991.0238.

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The health risk posed by effluent irrigation in a semi-arid area of Portugal was assessed. The residual contamination found on lettuces spray-irrigated with the effluent from a conventional trickling filter plant was compared to that of locally marketed lettuces and to the ICMSF (1974) standards. The 2-year study indicated initially high levels of faecal indicator bacteria on lettuces, but after irrigation ceased, the restricting climatic conditions sufficed to decontaminate them to local market quality within 5 days when no salmonellae could be detected. Although high, E.coli I levels were within the tolerance range of the ICMSF standards suggesting negligible excess exposure of consumers to faecal contamination from the effluent-irrigated lettuces.

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Hauser, M., W. Basso e P. Deplazes. "Dog and fox faecal contamination of farmland". Schweiz Arch Tierheilkd 157, n. 8 (5 agosto 2015): 449–55. http://dx.doi.org/10.17236/sat00030.

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Kaltenthaler, E. C., A. M. Elsworth, M. S. Schweiger, D. D. Mara e D. A. Brauxholtz. "Faecal contamination on children's hands and environmental surfaces in primary schools in Leeds". Epidemiology and Infection 115, n. 3 (dicembre 1995): 527–34. http://dx.doi.org/10.1017/s0950268800058696.

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SummaryGastro-intestinal diseases continue to be a major health problem in primary schools in the UK. This study, which took place in 20 primary schools in the Leeds area, investigated the presence of faecal indicator bacteria on children's hands and environmental surfaces. Faecal streptococci were used as an indicator of faecal contamination.A handwashing knowledge score was developed for each child. Those children with good hygiene knowledge had less faecal contamination on their hands (relative risk: 1·4. 95% CI = 1·09–1·81,P =0·005). Those schools with higher hand counts were more likely to have had a reported outbreak of gastroenteritis in the past. Values of the Townsend Deprivation Index, an indicator of deprivation, were compared with the hand results and those schools in high deprivation areas had higher hand counts. Of the swabs taken from surfaces in the toilet areas and classrooms, the carpets in the classrooms were the most frequently contaminated surfaces.

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Ball, Andrew S., Esmaeil Shahsavari, Leadin S. Khudur, Arturo Aburto-Medina e David J. Smith. "Factors Affecting Shellfish Quality in Terms of Faecal Contamination at Blakeney Point, East Anglia, UK". Water 13, n. 22 (11 novembre 2021): 3192. http://dx.doi.org/10.3390/w13223192.

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Relatively high E. coli and Faecal Streptococci (FS) numbers have been reported in the waters surrounding Blakeney Point, East Anglia, UK, an area containing significant shellfishery industries including mussels and cockles, despite the implementation of development works aimed at reducing residual contamination problems. The aim of this study was to evaluate the potential of using bacterial analyses and sterol profiling to assess the current levels and source of faecal pollution at Blakeney Point. No evidence of significant human faecal contamination of water in and around Blakeney Point could be found using either traditional microbiological analyses or sterol profile analysis. The presence of significant quantities of sitosterol, however, suggests that faecal contamination of water from birds does occur but at the concentration detected would not affect water quality. Analysis of cockles and mussels taken from the area show that negligible levels of coprostanol were present, confirming that faecal pollution was not causing any contamination issues. Apart from cholesterol, brassicasterol, an algal biomarker, as expected was dominant in shellfish flesh. The results confirm that current water treatment processes are successful in ensuring water quality at Blakeney Point and that a combination of microbial testing with sterol profile analysis confirmed that low microbial concentrations of faecal contaminants present in and around Blakeney Point most probably originate from migratory and/or resident bird species.

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Shah, Vikaskumar G., R. Hugh Dunstan, Phillip M. Geary, Peter Coombes, Timothy K. Roberts e Ellak Von Nagy-Felsobuki. "Evaluating potential applications of faecal sterols in distinguishing sources of faecal contamination from mixed faecal samples". Water Research 41, n. 16 (agosto 2007): 3691–700. http://dx.doi.org/10.1016/j.watres.2007.04.006.

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Wright, R. C. "The survival patterns of selected faecal bacteria in tropical fresh waters". Epidemiology and Infection 103, n. 3 (dicembre 1989): 603–11. http://dx.doi.org/10.1017/s0950268800031009.

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SUMMARYThe survival of various faecal bacteria used as indicators of the faecal contamination of water supplies has been investigated in a tropical environment (Sierra Leone). Isolates representing the thermotolerant coliform (TtC) and faecal streptococcus (FS) groups,Clostridium perfringensandSalmonellaspp. were studied over a 48 h period of immersion in water from three different sources. Survival patterns varied according to source type, but some general observations were made: a portion of the TtC group was apparently capable of substantial regrowth; FS organisms died off at a faster rate than TtC organisms initially, but survived longer; vegetative cells ofC. perfringensdied off rapidly; andSalmonellaspp. could survive for as long as the other faecal organisms tested. The implications of results for the analysis of tropical waters for faecal contamination are discussed.

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Lee, Chang Soo, Jason W. Marion e Jiyoung Lee. "A novel genetic marker for the rapid detection of Bacteroides fragilis in recreational water as a human-specific faecal indicator". Journal of Water and Health 9, n. 2 (25 aprile 2011): 253–64. http://dx.doi.org/10.2166/wh.2011.120.

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Bacteroides spp. has gained substantial interest among the suggested potential candidates for alternative faecal indicators for untreated recreational waters by the US EPA. Interest in Bacteroides as a faecal indicator is based upon the relative abundance of selected members of the Bacteroides genus in the human colon and human faeces. In this study, we developed a real-time PCR detection system based on gyrase B subunit genes (gyrB) specific to Bacteroides fragilis. The gryB-based method was compared with previously described 16S rRNA-based real-time qPCR methods and evaluated for specificity, sensitivity and robustness in detecting B. fragilis from untreated recreational water impacted by human and non-human faecal sources. The new gyrB-based system only detected B. fragilis, whereas the 16S rRNA-based methods generated cross-amplifications with other Bacteroides and Prevotella species. We used a procedure of prefiltration, filtration, sonication and DNA concentration in order to improve the DNA extraction efficiency and the sensitivity of the real-time PCR while removing interference. The amplification and sequencing of PCR products generated by the gyrB-based method confirmed that gyrB-amplified sequences only contained B. fragilis. This rapid method is useful for quantifying faecal contamination and may assist beach and watershed managers in elucidating possible contamination sources.

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27

DANIELS, M. J., M. R. HUTCHINGS e A. GREIG. "The risk of disease transmission to livestock posed by contamination of farm stored feed by wildlife excreta". Epidemiology and Infection 130, n. 3 (giugno 2003): 561–68. http://dx.doi.org/10.1017/s0950268803008483.

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Abstract (sommario):

Livestock feed is susceptible to contamination from wildlife excreta during on farm storage. Pathogens associated with diseases such as paratuberculosis, salmonella and cryptosporidiosis are present in wild rodent and bird excreta. Feed stores on four farms in the east of Scotland were monitored monthly over the winter of 1998/9 to quantify the levels of wildlife faecal contamination. A mean of 79·9 rodent (95% confidence interval: 37·5–165·9) and 24·9 (14·3–41·7) bird faeces were deposited per m2 of stored feed per month. It was estimated that individual cattle and sheep could encounter 1626 and 814 wildlife faeces over the winter.A model based on the numbers of infected faeces consumed per annum was used to estimate ‘infectious probabilities’ (Pinf) required to account for the reported prevalence of paratuberculosis, salmonella and cryptosporidiosis in sheep and cattle in the east of Scotland in 1998. Based on empirical data for input variables [the number of faeces encountered (Fe), the number ingested (Fi) and the prevalence of infection in wildlife species (Ip)], Pinf estimates ranged from 1·6×10−8 for cryptosporidiosis in sheep to 8·2×10−6 for paratuberculosis in cattle. The model suggested that ingestion of feed contaminated by wildlife faeces could account for the prevalence of all three diseases. Wildlife faecal contamination of stored feed should be given serious consideration as a potential source of infection to livestock.

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28

PIANETTI, A., L. SABATINI, F. BRUSCOLINI, F. CHIAVERINI e G. CECCHETTI. "Faecal contamination indicators, salmonella, vibrio and aeromonas in water used for the irrigation of agricultural products". Epidemiology and Infection 132, n. 2 (26 febbraio 2004): 231–38. http://dx.doi.org/10.1017/s095026880300181x.

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Abstract (sommario):

The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21·6% of the strains were adhesive and 12·6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers.

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29

Chiejina, S. N., e B. B. Fakae. "The ecology of infective larvae of bovine gastrointestinal trichostrongylids in dry season contaminated pastures in the Nigerian derived savanna". Journal of Helminthology 63, n. 2 (giugno 1989): 127–39. http://dx.doi.org/10.1017/s0022149x00008877.

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ABSTRACTFive experimental grass paddocks were sequentially contaminated with fresh bovine faeces containing known numbers of eggs of predominantly Haemonchus and Cooperia spp. during the 1984/85 dry season (November to March). Faecal, herbage and soil samples were examined at regular intervals between November and June in order to determine the rate of development and mortality of infective larvae (L3) in faeces, the pattern of herbage infestation with L3 and the role of faeces and soil as reservoirs of L3 during the dry season and early rains. L3 first appeared in faeces approximately 4 days post contamination (PC) and peak counts were obtained 28, 14, 7 and 14 days PC in the paddocks contaminated in December, January, February and March, respectively. The counts initially declined linearly at the rate of approximately 7535 L3/week and 10 947 L3/week in P2 and P4 respectively, due primarily to mortality but later there was an accelerated fall in the counts as the surviving L3 moved out of the faecal pads onto herbage. The overall trend of faecal larval populations in each paddock was therefore distinctly curvilinear. Although large numbers of L3 were present inside dry faecal pads in most paddocks throughout the dry season, none migrated on to herbage at that time of the year. Translation of L3 to herbage was very rapid and occurred simultaneously in all the paddocks 24 hours following the first heavy rainfall in late March. Consequently peak herbage infestations in all paddocks were coincident and occurred a few days after commencement of larval migration. The closer to the end of the dry season the contaminations were carried out, the larger were the subsequent early rains rise and the peak herbage infestation and the longer this infestation survived on herbage. No L3 were recovered from soil throughout the study, which suggests that faecal pads were the sole reservoir of L3 during the dry season and hence the source of the early rains herbage infestation.

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30

Meier, H., C. Koob, W. Ludwig, R. Amann, E. Frahm, S. Hoffmann, U. Obst e K. H. Schleifer. "Detection of enterococci with rRNA targeted DNA probes and their use for hygienic drinking water control". Water Science and Technology 35, n. 11-12 (1 giugno 1997): 437–44. http://dx.doi.org/10.2166/wst.1997.0774.

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Abstract (sommario):

Enterococci are useful indicators of faecal contamination with their high abundance in faeces and long survival in the environment and the possibility of indicating the source of contamination by species identification has lead to discussion of whether enterococci would be more reliable faecal indicators than E. coli. In an attempt to facilitate rapid and accurate identification of enterococci, 16S rRNA targeted oligonucleotide probes were designed by computer-aided analysis of more than 4,000 rRNA sequences. Probes were labelled non-isotopically with digoxigenin and fluorescent dyes. Conditions for specific hybridisation were optimised for dot blot hybridisation and whole cell hybridisation for all probes. With a combination of two probes, all hygienically important enterococci could be detected and 24 biochemically identified environmental isolates also hybridised with one of these probes. A quantitative detection method with a high sensitivity was developed based on filtration of water samples through polycarbonate filters, a short incubation on agar and microcolony filter hybridisation with fluorescently labelled probes followed by epifluorescence microscopy. Within 8–20h sampling a specific identification of enterococcal microcolonies was possible. With this method 15/32 well- and tap-water sources from the Mainz area were identified as being of substandard quality. The proposed method detects faecal contamination significantly earlier than conventional methods and could be helpful in the hygienic monitoring of drinking water.

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31

Smith, G. R., L. M. Wallace e D. E. Noakes. "Experimental observations on the pathogenesis of necrobacillosis". Epidemiology and Infection 104, n. 1 (febbraio 1990): 73–78. http://dx.doi.org/10.1017/s0950268800054546.

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SUMMARYEarlier studies showed that the minimum infective dose (>106 organisms) of a virulent strain of Fusobacterium necrophorum could be greatly reduced by suspending the fusobacteria in sub-lethal doses of cultures of other bacteria such as Escherichia coli before inoculating mice subcutaneously.In the present study the infective dose of the same strain of F. necrophorum was reduced by a factor of >103 by suspending the fusobacteria in sub-lethal doses of 5% homogenate of gaur or wallaby faeces. Sterile faecal filtrate had no such effect. The sites of low grade infection produced by the prior subcutaneous injection of E. coli culture or gaur faecal suspension were susceptible to superinfection by doses of F. necrophorum far below those required to infect normal tissue.This work helps to explain the production of necrobacillosis by the faecal contamination of small wounds. It proved impossible, however, to produce necrobacillosis in mice by the subcutaneous injection of faecal suspensions from 33 farm cattle. This suggests that the proportion of cattle with virulent F. necrophorum in their faeces is low.

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32

GURLER, Ali Tumay, Cenk Soner BOLUKBAS, Aytac AKCAY, Gokmen Zafer PEKMEZCI, MUSTAFA AÇICI e Şinasi Umur. "Role of cat and dog faeces in the contamination of sand playgrounds in public parks by Toxocara spp." Medycyna Weterynaryjna 76, n. 08 (2020): 6436–2020. http://dx.doi.org/10.21521/mw.6436.

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Abstract (sommario):

Toxocariasis is one of the most important parasitic zoonoses affecting human health. The main source of toxocariasis in humans is dog and cat faeces, which are primarily responsible for the contamination of urban areas with Toxocara spp. eggs. In this study, the relationship between dog or/and cat faeces and contamination of sand playgrounds in public parks with Toxocara spp. eggs was investigated. A total of 596 sand and 276 faecal samples (148 dog and 128 cat faeces samples) were collected from 52 public parks in Samsun. Toxocara spp. eggs were identified in 7% of sand samples, 33% of cat faeces samples and 9.5% and dog faeces samples. A positive correlation was found between the presence of faeces and the contamination of sand samples. The incidence of sand contamination was increased 8.3 times if a park contained dog or/and cat faeces, and the incidence was much greater if the faeces were infected with Toxocara spp. ova. Cat faeces had a greater effect on the contamination of sand than did dog faeces. The risk was 12.5 and 27 times greater if a park contained only cat faeces and infected cat faeces, respectively. However, no Toxocara spp. eggs were found in sand samples from parks that contained only dog faeces.

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33

Gibb, Karen, Xavier Schobben e Keith Christian. "Frogs host faecal bacteria typically associated with humans". Canadian Journal of Microbiology 63, n. 7 (luglio 2017): 633–37. http://dx.doi.org/10.1139/cjm-2017-0119.

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Abstract (sommario):

Tree frogs commonly access drinking water tanks; this may have human health implications. Although amphibians might not be expected to host mammalian faecal indicator bacteria (FIB), it is possible that they may have human FIB on their skin after exposure to human waste. We collected faeces and skin wash from green tree frogs (Litoria caerulea) from a natural environment, a suburban site, and a suburban site near a creek occasionally contaminated with sewage effluent. We used molecular techniques to test for FIB that are routinely used to indicate human faecal contamination. Enterococci colonies were isolated from both faecal and skin wash samples, and specific markers (Enterococcus faecium and Bacteroides thetaiotaomicron) were found in frog faeces, demonstrating that these markers are not human- or mammalian-specific. Bacteroides thetaiotaomicron was detected in frogs from both natural and urban sites, but E. faecium was only associated with the sewage impacted site.

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34

Parmar, Vikas, e Madhubala Purohit. "Faecal Contamination in Ground Water Resources of Urban Areas of Ujjain". International Journal of Scientific Research and Management 8, n. 03 (28 marzo 2020): 42–46. http://dx.doi.org/10.18535/ijsrm/v8i03.b01.

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Abstract (sommario):

Ground water is one of the most important natural resource next to air being essential for life. Quality of ground water depends upon natural process, such as wet/dry condition, salts, many geogenic and anthropogenic activities. Among all contamination ground water is more susceptible to microbial contamination. According to WHO report about 80% of all diseases in human being are caused due to drinking water contaminated by bacteria of faecal origin. Various water born diseases are prevalent in Ujjain like typhoid, dysentery, jaundice, amebeosis, colitis etc. Purpose of the study was to assess the bacterial contamination of faecal origin in ground water resources of urban area of Ujjain. For this ground water samples (well, bore well and hand pump) were collected from 6 sub areas of Ujjain city. For the assessment of bacterial contamination of faecal origin H2S strip test of Manja,et.al.(1982) was used. Results clearly indicated that bore well water was found to be safe for drinking, domestic and other purposes.

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35

Le Guyader, F., L. Miossec, L. Haugarreau, E. Dubois, H. Kopecka e M. Pommepuy. "RT-PCR evaluation of viral contamination in five shellfish beds over a 21-month period". Water Science and Technology 38, n. 12 (1 dicembre 1998): 45–50. http://dx.doi.org/10.2166/wst.1998.0496.

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Abstract (sommario):

Five shellfish beds were sampled for 21 months and evaluated for microbial contamination. Viral extraction was performed on dissected tissues and the clinically most important enteric viruses (hepatitis A virus, small round structured virus, rotavirus and enterovirus) were searched for by RT-PCR and hybridization. Among the 104 samples analysed, 66% were contaminated by at least one virus and 34% were negative for any virus. The two sites regularly contaminated by faecal coliforms had the highest percentage of viral contamination and HAV was detected only in these sites. However, sampling sites meeting the criteria for commercialisation showed occasional viral contamination and viruses were detected in samples with no faecal coliform contamination.

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36

Rakesh, Pant, Kukreti Samiksha, Kaur Harmanpreet, Rawat Mansi, Kumar Vijay e Gupta Amit. "Qualitative and quantitative enumeration of Coliform bacteria in song river water in rural area of Dehradun". Journal of medical pharmaceutical and allied sciences 11, n. 2 (30 marzo 2022): 4534–38. http://dx.doi.org/10.55522/jmpas.v11i2.2042.

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Abstract (sommario):

As India’s population is growing so is its water demand and corresponding water contamination. Water is a very essential element in formation of life and is an essential requirement for living organisms to thrive. Therefore, it is very important that the drinking water available must be free of any contamination and proper measures be taken in that direction. Faecal contamination poses crucial threat to people having an impaired immune system and can be life threatening. Microbiological contamination causes serious health issues in human being. In case microbiological contamination found in water, it means that water quality is very poor and this type of water causes Gastrointestinal, Urinary tract infection, dysentery, diarrhoea and typhoid disease. Keywords: Faecal coliform, Pathogenic Bacteria, Song River, Dehradun, Water Quality.

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37

Copeland, Curtis C., Benjamin B. Beers, Meghan R. Thompson, Relana P. Fitzgerald, Leah J. Barrett, Jesus E. Sevilleja, Sayonara Alencar, Aldo A. M. Lima e Richard L. Guerrant. "Faecal contamination of drinking water in a Brazilian shanty town: importance of household storage and new human faecal marker testing". Journal of Water and Health 7, n. 2 (1 febbraio 2009): 324–31. http://dx.doi.org/10.2166/wh.2009.081.

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Abstract (sommario):

Worldwide, contaminated drinking water poses a major health threat, particularly to child development. Diarrhoea represents a large part of the water-related disease burden and enteric infections have been linked to nutritional and growth shortfalls as well as long-term physical and cognitive impairment in children. Previous studies detailed the frequency of infection and the consequences for child health in a shanty town in north-east Brazil. To determine the frequency of contaminated water, we measured faecal contamination in primary drinking water samples from 231 randomly selected households. Risk for contamination was compared across source and storage types. Nearly a third of the study households (70/231: 30.3%) had contaminated drinking water; the source with the highest frequency of contamination was well water (23/24: 95.8%). For tap water, the type of storage had a significant effect on the susceptibility to contamination (χ2=12.090; p=0.007). The observed pattern of contamination demonstrated the relative potential contributions of both source and storage. With evidence that supports the inclusion of source and storage in water quality surveys, this study, like others, suggests that contaminated drinking water in storage vessels may be an important factor for the documented diarrhoea disease burden in the Brazilian shanty town.

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38

Hou, Xiaoshu, Lei Chen, Guoyuan Wei, Yongwei Gong e Zhenyao Shen. "Factors affecting microbial and physico-chemical pollutants in stormwater in a typical Chinese urban catchment". Environmental Science: Processes & Impacts 20, n. 12 (2018): 1697–707. http://dx.doi.org/10.1039/c8em00303c.

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Abstract (sommario):

The discharge characteristics of faecal coliform are very different from those of physico-chemical pollutants. The antecedent dry period factors count a great deal for faecal coliform contamination in urban stormwater.

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39

Malema, Mokaba Shirley, Jean-Marc Mwenge Kahinda, Akebe Luther King Abia, Roman Tandlich, Bongumusa M. Zuma e Eunice Ubomba-Jaswa. "The efficiency of a low-cost hydrogen sulphide (H2S) kit as an early warning test for assessing microbial rainwater quality and its correlation with standard indicators microorganisms". Nova Biotechnologica et Chimica 18, n. 2 (1 dicembre 2019): 133–43. http://dx.doi.org/10.2478/nbec-2019-0016.

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Abstract (sommario):

Abstract Testing microbial quality of the harvested rainwater remains a challenge in many countries. The H2S test kit is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. This study compares its efficiency with the standard indicators microorganisms in the detection of faecal contamination of rainwater in South Africa. A total of 88 rainwater samples were collected from various tanks in the Eastern Cape, South Africa over three months in 2016. The collected samples were analysed for faecal bacterial contamination using the H2S test kit, Colilert-18/Quanti-tray®/2000 and the membrane filtration technique for faecal coliforms (MFT). The correspondence rate of the H2S test kit with MFT was 88 %, while for the Colilert® it was 76 %. The H2S test kit confirmed faecal contamination when concentrations of standards indicators microorganisms were 5 most-probable number of cells/100 cm3 or higher. Overall, the best correspondence of the H2S test kit with Colilert® was observed at E. coli concentrations above 50 most-probable number of cells/100 cm3. Results of the H2S test kit correlated better with MTF, while the medium used has strongly influenced the enumeration of faecal contamination. Results point to strong effect of media used and revealed the need to calibrate the correspondence between the standard indicator microorganisms and the H2S test kit under local conditions for specific settings.

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40

Stratton, Helen, Warish Ahmed e Mohammad Katouli. "A consensus: microbial source tracking (MST) in water". Microbiology Australia 30, n. 1 (2009): 30. http://dx.doi.org/10.1071/ma09030.

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Abstract (sommario):

Traditionally, water quality regulation and protection of public health has relied on culture-based methods that quantify faecal indicators such as the coliforms. Since Escherichia coli represents over 97% of the thermotolerant coliforms, it has been used extensively as a key indicator of faecal contamination in water testing industry. However the presence of E. coli or other coliforms (and more recently enterococci) does not provide any information regarding the source of contamination and therefore is not always an effective indicator of actual risk to humans. While human/animal faecal contamination of water can pose a serious health risk to public, the risk can be managed more efficiently and effectively if the source is known. In this respect, microbial source tracking (MST) can be used as an efficient tool by water managers to improve management of public health.

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41

Roll, B. M., e R. S. Fujioka. "Sources of faecal indicator bacteria in a brackish, tropical stream and their impact on recreational water quality". Water Science and Technology 35, n. 11-12 (1 giugno 1997): 179–86. http://dx.doi.org/10.2166/wst.1997.0730.

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This study assessed the contribution of water from a stream on the microbial quality of a swimming beach. The faecal indicator bacterial concentrations/100mL in Kaelepulu Stream greatly exceeded the three USEPA recreational water quality standards (200 faecal coliform, 126 E. coli, 33 enterococci). The primary sources for these indicator bacteria were determined to be environmental/non-point sources (tributary streams, storm drains, duck faeces, soil, rain). Sewage discharge is another, although sporadic source. Monitoring waters for C. perfringens was the most reliable indicator of sewage contamination primarily because soil is not a major source of this bacterium. Water from this inland system was a source of faecal indicator recovered from shoreline water samples obtained from Kailua Beach, one of the most popular beaches in the state of Hawaii.

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42

Journal, Baghdad Science. "Bacterial contamination of AL-Habania and AL-Tharthar reservoirs". Baghdad Science Journal 9, n. 4 (2 dicembre 2012): 600–607. http://dx.doi.org/10.21123/bsj.9.4.600-607.

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Abstract (sommario):

Bacterial contamination of AL-Habania and AL-Tharthar reservoirs were studied during the period from February 2001 to January 2002, samples were collected from four stations in AL-Habania reservoir (AL-Warrar, AL-Theban regulator, middle of the reservoir and the fourth was towards AL-Razzaza reservoir) and from two stations at AL-Tharthar reservoir (Ein AL-Hilwa and the middle of the reservoir). Coliform bacteria, faecal Coliforms, Streptococci, faecal Streptococci and total count of bacteria were used as parameters of bacterial contamination in waters of both reservoirs through calculating the most probable number. Highest count of Coliform bacteria (15000 cell/100ml) was recorded at Ein AL-Hilwa and lowest count at AL-Theban regulator and middle of AL-Tharthar reservoirs and reached (400 cell/100ml), faecal Coliform bacteria ranged between less than (300 cell/100ml) to (2300 cell/100ml). Total Streptococci ranged between less than (300 cell/100ml) to (24000 cell/100ml), faecal Streptococci ranged between less than (300 cell/100ml) to (900 cell/100ml). Total bacterial count showed variable values due to ecological changes at the stations of study which reached (3980 cell/ml) in the forth station towards AL-Razzaza reservoir and was declined to (580 cell/ml) at the middle of AL-Tharthar reservoir. Results were discussed in the research text.

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43

Ottoson, Jakob, e Thor Axel Stenström. "Faecal contamination of greywater and associated microbial risks". Water Research 37, n. 3 (febbraio 2003): 645–55. http://dx.doi.org/10.1016/s0043-1354(02)00352-4.

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44

Ouattara, Nouho Koffi, Anouk de Brauwere, Gilles Billen e Pierre Servais. "Modelling faecal contamination in the Scheldt drainage network". Journal of Marine Systems 128 (dicembre 2013): 77–88. http://dx.doi.org/10.1016/j.jmarsys.2012.05.004.

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45

Lee, R. J., e O. C. Morgan. "Environmental factors influencing the microbiological contamination of commercially harvested shellfish". Water Science and Technology 47, n. 3 (1 febbraio 2003): 65–70. http://dx.doi.org/10.2166/wst.2003.0162.

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Abstract (sommario):

Filter-feeding bivalve molluscs (such as oysters, clams, mussels and cockles) can concentrate contaminants from the water column. The extent of faecal contamination in shellfish is usually estimated by determining the concentration of faecal coliforms and/or Escherichia coli. Three sample points in each of three geographically separate commercial shellfisheries were selected for analysis for the effect of season, spring/neap and high/low tidal cycles, rainfall and wind direction on the results of routine E. coli monitoring. General linear modelling was used for the analyses. The principle factors affecting the contamination of shellfisheries were season, high/low tidal cycle and rainfall. The effects varied between harvesting areas and between individual sampling points within harvesting areas. Undertaking such analyses for all harvesting areas would contribute to the management of monitoring programmes and assist in the evaluation of potentially contaminating sources, such as sewage discharges. The type of analyses undertaken on E. coli monitoring data would also be pertinent for the analysis of putative viral indicators, such as F+ coliphage, and could be extended to data on bacterial and viral pathogens.

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46

Jovanovic, Dusan, Rebekah Henry, Rhys Coleman, Ana Deletic e David McCarthy. "Integrated conceptual modelling of faecal contamination in an urban estuary catchment". Water Science and Technology 72, n. 9 (15 luglio 2015): 1472–80. http://dx.doi.org/10.2166/wst.2015.363.

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Abstract (sommario):

Urban stormwater is regarded as a key input of faecal contamination in receiving water bodies and therefore, a major concern for health risks associated with aquatic recreation. Wastewater leakages, cross connections and overflows, together with faeces washed from surfaces during rainfall events, are possible origins of faecal contamination which enter these water bodies through stormwater drains. This paper applies conceptual models to a case study of the Yarra River estuary to understand the relative importance of fluxes derived from an urban creek and the 219 urban stormwater pipes which drain directly to the estuary as compared with other inputs, such as the Yarra River itself. Existing hydrologic-microorganism models were used for the estimation of the inputs from riverine and urban stormwater fluxes. These predictions were applied as boundary conditions for a new, highly simplified, model which accounts for the transport and survival of faecal microorganisms in the estuary. All models were calibrated using a rich dataset, containing over 2,000 measured Escherichia coli concentrations. Mass balances from the riverine and stormwater models indicate the limited influence of urban stormwater drains on the estuary during dry weather; less than 0.05% to 10% (5th and 95th percentile; median 0.5%) of the total daily E. coli load entering the estuary was derived from urban stormwater drains. While wet weather contributions from stormwater drains could be more significant (2% to 50%; 5th and 95th percentile), the average contribution remained marginal (median 10%). Sensitivity testing of the estuarine microorganism model by switching off stormwater boundary conditions resulted in minimal model efficiency reduction; this may reflect the low average daily contribution from urban stormwater drains. While these results confirm previous studies which show that E. coli loads derived from stormwater drains are dwarfed by other inputs, it is essential to note that these results also demonstrate that some conditions reveal the opposite; high proportions from stormwater are possible when combined with low riverine inputs and high urban rainfall. Furthermore, this study focuses on the overall impacts of direct urban stormwater inputs on the faecal contamination levels within the estuary, and localized impacts would certainly require further investigation.

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47

Papini, R., E. Campisi, E. Faggi, G. Pini e F. Mancianti. "Prevalence of Toxocara canis eggs in dog faeces from public places of Florence, Italy". Helminthologia 49, n. 3 (1 settembre 2012): 154–58. http://dx.doi.org/10.2478/s11687-012-0031-0.

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Abstract (sommario):

AbstractTo determine whether canine faecal contamination may represent a source of environmental contamination with Toxocara canis eggs within the urban area of Florence, a total number of 754 dog faeces were collected in 7 public places and examined by routine floatation technique during one-year period. The total prevalence of intestinal nematode eggs was 8.6 %. Trichuris vulpis (4.6 %) eggs were the most prevalent followed by T. canis (3.6 %) and Ancylostomidae (1.7 %) eggs. Mixed infections included T. canis/T. vulpis (0.7 %), Ancylostomidae/T. canis (0.4 %), and Ancylosto-midae/T. vulpis (0.3 %). Total prevalence of intestinal nematode eggs was significantly higher in spring than in winter (OR = 2.06). Our results indicate a low prevalence of T. canis eggs suggesting that dog faeces left on soil are unlikely to cause high environmental contamination with T. canis eggs in the town of Florence.

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48

Saim, Norashikin, Rozita Osman, Dayang Ratena Sari Abg Spian, Mohd Zuli Jaafar, Hafizan Juahir, Md Pauzi Abdullah e Fuzziawati Ab Ghani. "Chemometric approach to validating faecal sterols as source tracer for faecal contamination in water". Water Research 43, n. 20 (dicembre 2009): 5023–30. http://dx.doi.org/10.1016/j.watres.2009.08.052.

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49

Schönning, Caroline, Rhys Leeming e Thor Axel Stenström. "Faecal contamination of source-separated human urine based on the content of faecal sterols". Water Research 36, n. 8 (aprile 2002): 1965–72. http://dx.doi.org/10.1016/s0043-1354(01)00427-4.

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50

Islam, M. M. Majedul, Ekaterina Sokolova e Nynke Hofstra. "Modelling of river faecal indicator bacteria dynamics as a basis for faecal contamination reduction". Journal of Hydrology 563 (agosto 2018): 1000–1008. http://dx.doi.org/10.1016/j.jhydrol.2018.06.077.

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