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Urban surface water is increasingly used for contact recreation. Predicting Escherichia coli (E. coli) concentrations in these waters can support early warning of bathers and explain the dynamics of this faecal pollution indicator. This study provides the first overview of the scientific knowledge on E. coli prediction models for freshwater in cities. Modelling techniques for urban waters are comparable to those for other freshwater environments, with multiple linear regression being the most frequently used approach. While previously reviewed E. coli prediction models for freshwater beaches predominantly target lakes, urban models mainly target rivers. We found indications that model performance for urban rivers is lower than for recreational beach water in rivers in general. Reported performance metrics indicate that not all relevant sources are captured by the models. Future research should solve the lack of insight into model performance for specific applications and verify the suggested directions to improve models' accuracy. [ABSTRACT FROM AUTHOR]

Wastewater surveillance represents an alternative approach to regulating contamination and the early detection of infectious agents and outbreaks of diseases of public health importance. This study evaluated domestic wastewater effects on recreational waters in estuarine and seawater bodies in Guayas and Santa Elena provinces in Ecuador, South America. Fecal indicator bacteria (thermotolerant coliforms) served as key indicators for evaluation. Physical, chemical, and microbiological quality markers following the Ecuadorian environmental quality standard and the discharge of effluents to the water resource were analyzed. Samples were collected from 44 coastal sites and 2 oxidation lagoons during the dry and rainy seasons of 2020 and 2021, respectively. SARS-CoV-2 RNA was detected in samples with higher E. coli concentrations using reverse transcription quantitative PCR to detect the genes N and ORF1ab. All samples analyzed for SARS-CoV-2 showed Ct ˂ 40 for at least one gene. Four samples showed at least 20 genome copies of gene N per reaction. These were at an artisanal fishing port, an estuarine area (Palmar), a recreational bay, and an oxidation lagoon. A moderate correlation was found between SARS-CoV-2 RNA, thermotolerant coliform and E. coli (p-value ≤ 0.0037), and a strong and positive correlation between thermotolerant coliform and E. coli. (p-value ≤ 0.00001), highlighting the utility of these established parameters as a proxy of the virus. Significant differences were found in the concentrations of thermotolerant coliforms between seasons (p-value = 0.016) and sites (p-value = 0.005). The highest levels of coliforms were found in the dry season (63000 MPN/100 mL) in Anconcito and during the rainy season (14000 MPN/100 mL) at Esterillo in Playas County. It is recommended that the decentralized autonomous governments of the surveyed provinces in Ecuador implement urgent corrective actions and establish medium-term mechanisms to minimize a potential contamination route. Additional parameters must be included in the monitoring, such as Enterococcus and intestinal parasites, due to their public health implications. In the oxidation lagoons, maintenance actions must be carried out, including the dissolution of sediments, an increase in water retention times, and in situ treatment of the sludge, to improve the system's performance. [ABSTRACT FROM AUTHOR]

Escherichia coli is a promising subject for globally coordinated surveillance of antimicrobial resistance (AMR) in water environments due to its clinical relevance and widespread use as an indicator of fecal contamination. Cefotaxime-resistant E. coli was recently evaluated favorably for this purpose by the World Health Organization TriCycle Protocol, which specifies tryptone bile x-glucuronide (TBX) medium and incubation at 35°C. We assessed comparability with the U.S. Environmental Protection Agency-approved method for E. coli quantification, which uses membrane-thermotolerant E. coli (mTEC) agar and incubation at 44.5°C, in terms of recovery of E. coli and cefotaxime-resistant E. coli from wastewater influent and surface waters. Total E. coli concentrations in wastewater influent were 106-108 CFU/100 mL, while cefotaxime-resistant E. coli were ~100-fold lower. Total E. coli in surface waters were ~10² CFU/100 mL, and cefotaxime-resistant isolates were near the limit of detection (0.4 CFU/100 mL). Total and putative cefotaxime-resistant E. coli concentrations did not differ significant ly between media or by incubation method; however, colonies isolated on mTEC were more frequently confirmed to species (97.1%) compared to those from TBX (92.5%). Incubation in a water bath at 44.5°C significantly decreased non-specific background growth and improved confirmation frequency on both media (97.4%) compared to incubation at 35°C (92.3%). This study helps to advance globally coordinated AMR in water environments and suggests that the TriCycle Protocol is adaptable to other standard methods that may be required in different locales, while also offering a means to improve specificity by decreasing the frequency of false-positive identification of cefotaxime-resistant E. coli by modifying incubation conditions. [ABSTRACT FROM AUTHOR]

Understanding the dynamic change in abundance of both fecal and opportunistic waterborne pathogens in urban surface water under different abiotic and biotic factors helps the prediction of microbiological water quality and protection of public health during recreational activities, such as swimming. However, a comprehensive understanding of the interaction among various factors on pathogen behavior in surface water is missing. In this study, the effect of salinity, light, and temperature and the presence of indigenous microbiota, on the decay/persistence of Escherichia coli and Pseudomonas aeruginosa in Rhine River water were tested during 7 days of incubation with varying salinity (0.4, 5.4, 9.4, and 15.4 ppt), with light under a light/dark regime (light/dark) and without light (dark), temperature (3, 12, and 20 °C), and presence/absence of indigenous microbiota. The results demonstrated that light, indigenous microbiota, and temperature significantly impacted the decay of E. coli. Moreover, a significant (p<0.01) four-factor interactive impact of these four environmental conditions on E. coli decay was observed. However, for P. aeruginosa, temperature and indigenous microbiota were two determinate factors on the decay or growth. A significant three-factor interactive impact between indigenous microbiota, temperature, and salinity (p<0.01); indigenous microbiota, light, and temperature (p<0.01); and light, temperature, and salinity (p<0.05) on the decay of P. aeruginosa was found. Due to these interactive effects, caution should be taken when predicting decay/persistence of E. coli and P. aeruginosa in surface water based on a single environmental condition. In addition, the different response of E. coli and P. aeruginosa to the environmental conditions highlights that E. coli monitoring alone underestimates health risks of surface water by non-fecal opportunistic pathogens, such as P. aeruginosa. Key points: Abiotic and biotic factors interactively affect decay of E. coli and P. aeruginosa E.coli and P.aeruginosa behave significantly different under the given conditions Only E. coli as an indicator underestimates the microbiological water quality [ABSTRACT FROM AUTHOR]

Background: Escherichia coli, a ubiquitous inhabitant of the gut microbiota, has been recognized as an indicator of fecal contamination and a potential reservoir for antibiotic resistance genes. Its prevalence in drinking water sources raises concerns about the potential dissemination of antibiotic resistance within aquatic ecosystems and the subsequent impact on public health. The ability of E. coli to acquire and transfer resistance genes, coupled with the constant exposure to low levels of antibiotics in the environment, underscores the need for comprehensive surveillance and rigorous antimicrobial stewardship strategies to safeguard the quality and safety of drinking water supplies, ultimately mitigating the escalation of antibiotic resistance and its implications for human well-being. Methods: WG5D strain, isolated from a drinking water distribution source in North-West Province, South Africa, underwent genomic analysis following isolation on nutrient agar, anaerobic cultivation, and DNA extraction. Paired-end Illumina sequencing with a Nextera XT Library Preparation kit was performed. The assembly, annotation, and subsequent genomic analyses, including phylogenetic analysis using TYGS, pairwise comparisons, and determination of genes related to antimicrobial resistance and virulence, were carried out following standard protocols and tools, ensuring comprehensive insights into the strain's genomic features. Results: This study explores the notable characteristics of E. coli strain WG5D. This strain stands out because it possesses multiple antibiotic resistance genes, encompassing tetracycline, cephalosporin, vancomycin, and aminoglycoside resistances. Additionally, virulence-associated genes indicate potential heightened pathogenicity, complemented by the identification of mobile genetic elements that underscore its adaptability. The intriguing possibility of bacteriophage involvement and factors contributing to pathogenicity further enriches our understanding. We identified E. coli WG5D as a potential human pathogen associated with a drinking water source in South Africa. The analysis provided several antibiotic resistance-associated genes/mutations and mobile genetic elements. It further identified WG5D as a potential human pathogen. The occurrence of E. coli WG5D raised the awareness of the potential pathogens and the carrying of antibiotic resistance in drinking water. Conclusions: The findings of this study have highlighted the advantages of the genomic approach in identifying the bacterial species and antibiotic resistance genes of E. coli and its potential as a human pathogen. [ABSTRACT FROM AUTHOR]

With a focus on the impact of the Rustumiya sewage treatment facility, the physio-chemical and indicator bacterial contamination pollution of the Diyala River (Iraq) was examined. The Diyala River in Baghdad was sampled on a monthly basis from March 2022 to February 2023 for surface water and sediment. The findings demonstrated seasonal and geographical variation in physiochemical parameters (pH, EC, salinity, and TDS) and bacteriological markers (TC, FC, E. coli, and FS). The research procedures and methods showed that some physicochemical parameters (pH, EC, TDS) in sediment exceeded their standard limits concerning aquatic life protection in spring and summer. The level of bacteriological pollution in the water and sediments, evaluated by tracking of faecal indicator bacteria (E. coli and Enterococci), during the autumn and winter seasons had the largest concentration of bacterial contaminants. In this study, the main finding was the majority of the studied stations had water classified as not recommended or unacceptable and sediment classified as acceptable or conservatively accepted. The source of contamination, determined by the ratio value of faecal coliform bacteria to faecal Streptococcus, was from human origin in the majority of studied stations, and from mixed origin during the spring and summer. Bacterial indicators in this research exhibited both quantitative and qualitative fluctuation, suggesting their potential utility as a bio-indicator for contamination of water and sediment in the Diyala River. [ABSTRACT FROM AUTHOR]

Simple Summary: The contamination of coastal waters, unhealthy conditions and inadequate handling practices tend to reduce the sanitary quality of fishery products, thus impacting its marketing. With this in mind, we investigate the microbiological quality of the Octopus insularis in each stage of the production chain, comprehending capture, post-capture, processing and commercialization, in terms of the presence of total and fecal coliforms at the Veracruz Reef System, Gulf of Mexico. The environmental and anthropogenic influence on the space–temporal concentration of coliforms were analyzed in sea water, fresh octopus, fresh water, ice and octopus, both packed in ice and boiled. Most relevant results indicated that coliforms are present in the octopus production chain, being highest in the marketing stage. The coliform concentration increased during the rainy season and was highest in the reefs closer to the coast, which has a major anthropogenic influence. These results point out the urgent need to implement an efficient cold chain with adequate handling practices to try to reverse these microbiological conditions and improve the octopus quality and food safety. Coliforms are relatively common in aquatic environments, but their concentrations can be increased by environmental changes and anthropogenic activities, thus impacting fisheries resources. To determine the microbiological quality in the octopus production chain (capture, post-capture, processing and commercialization), total (TC) and fecal (FC) coliforms were quantified in sea water, fresh octopus, fresh water, ice and octopus in two presentations: packed in ice and boiled. Samples came from fishing zones Enmedio, Chopa and La Gallega at the Veracruz Reef System (VRS) during dry, rainy and windy seasons. The coliforms were determined using the most probable number technique (MPN). The most relevant results indicated that octopus packed in ice coming from the commercialization stage had FC levels >540 MPN/100 g, which exceeded the permissible limits (230 MPN/100 g). Therefore, these products present a risk for human consumption. Differences in FC were observed in octopuses between the three fishing zones (H = 8.697; p = 0.0129) and among the three climatic seasons, increasing during the rainy season, highlighting La Gallega with 203.33 ± 63 MPN (H = 7.200; p = 0.0273). The results provide evidence of the environmental and anthropogenic influences on coliform concentrations and the urgent need to implement an efficient cold chain throughout octopus production stages with adequate handling practices to reverse this situation. [ABSTRACT FROM AUTHOR]

The potability of water, including underground sources, is constantly affected by human activities. To assess water quality and water security in rural and urban areas of southern Brazil, a quantitative, retrospective analysis of water samples collected monthly by the Brazilian health authorities (19,687 samples from 2013 to 2021) was performed. In rural areas, 5,979 water samples (77.54%) were found to be contaminated by coliform bacteria and 3,431 (44.50%) by Escherichia coli. In addition, 1,616 (20.95%) of the contaminated samples were significantly correlated with rainfall amount. In urban areas, 1,268 (10.95%) of the samples contained coliform bacteria and 293 (2.53%) of these samples contained E. coli, with the factor of rainfall associated with 1,081 samples (9.33%) with bacterial contamination. In terms of physicochemical parameters, turbidity exceeded the national standard (5 uT) in 448 (2.32%) samples and fluoride fell below the required level (0.8 mg/L) in 106 samples (0.54%). The presence of free residual chlorine (0.2–2.0 mg/L) was verified in 846 samples (14.38%) in rural areas and in 10,825 samples (56.13%) in urban areas. These results suggest a strong association between rainfall factors and physicochemical alterations, as well as the risk of greater microbial contamination of water for human consumption. [ABSTRACT FROM AUTHOR]

The presence and level of faecal indicator bacteria are important factors in estimating the microbiological quality of surface water and the risk of human infection upon exposure to this water. Until 2014, ISO 9308-1:2000 was available and used to enumerate faecal indicator Escherichia coli in bathing water. In 2014, this ISO was technically revised and replaced by ISO 9308-1:2014. This ISO introduced a less selective method for enumeration of E. coli that allows non-specific growth from waters containing high levels of bacteria, such as surface waters. This implies that currently there is no suitable reference membrane filtration method for the compliance monitoring of official bathing sites for E. coli according to the European Bathing Water Directive. Here, the performance characteristics of three chromogenic culture media, namely Tryptone Bile X-glucuronide (TBX) agar, Chromogenic Coliform Agar (CCA), and CHROMagar E. coli/Coliform (ECC) were investigated at 44 °C for water with varying levels of bacteria according to ISO 13843:2017. Based on performance characteristics, colony counts, and practical usage, TBX appeared the most suitable culture medium for the enumeration of E. coli in bathing water and other waters with high levels of background bacteria, such as surface water in agricultural areas and wastewater discharge points. [ABSTRACT FROM AUTHOR]

Kuwait Bay's southern shore is home to several facilities used for various purposes, impacting the beaches' ecosystems and coastal environment. Furthermore, the presence of numerous stormwater outfalls on Kuwait Bay's southern shores may be one of the sources of pollutants that are discharged from these outfalls. This research aims to evaluate the microbiological quality of seawater near 5 selected stormwater outfalls located on Kuwait Bay's recreational water by measuring the levels of microbial bacteria such as fecal coliform (FC), and Escherichia Coli. (E. Coli), and fecal streptococci (FS), and water quality parameters including temperature, pH, electrical conductivity (EC), and dissolved oxygen (DO). The analytical results were compared with Kuwait Environmental Public Authority (EPA) requirements for water discharge to Kuwait Bay to assess the suitability of the beaches for recreational activities. The field results revealed the presence of mildly alkaline seawater samples, a range of fresh to saline water types, and various DO levels from very low to acceptable levels. noteworthy, the microbial indicators were extremely high and far beyond EPA guidelines, demonstrating extensive microbiological pollution at these locations. The mean FC/FS ratios of C18 had the greatest mean FC/FS ratio (16.75), signifying human contamination. C3 and C5 indicated human waste in mixed pollution with averages of (3.45 and 2.34 respectively), whereas C8 and C10 showed human contamination with average values (of 5.98, and 4.21 respectively). It is suggested that the seawater quality close to wastewater outfalls be frequently evaluated and treated using efficient onsite treatment technologies to decrease the amount of polluted wastewater discharged directly to the beaches. [ABSTRACT FROM AUTHOR]

The Barataria-Terrebonne National Estuary Program (BTNEP), Thibodaux, Louisiana, worked with the Louisiana Department of Environmental Quality and the EPA Gulf of Mexico Division to reduce releases of untreated sewage in the Bayou Folse and Bayou Lafourche watersheds using water monitoring (WM), onsite sewage disposal systems (OSDS) inspections, a home sewage assistance program (HSAP), and public and homeowner education. Both the B. Folse and Lafourche are coastal watersheds impaired by forced drainage, malfunctioning OSDS, and agricultural runoff. Bayou Lafourche is the region's water supply for ~300,000 people. The Bayou Lafourche Freshwater District conducted B. Folse inspections from 2020 - 2021 and recorded high re-inspection failure rates at 62%, probably due to repair cost. Pre-implementation (PI) data for the B. Folse HSAP spanned from 2016-2019 and post-implementation (POI) data spanned from 2019-2021. In B. Lafourche, only PI data was collected from 2019-2020 but demonstrated fewer excursions for dissolve oxygen and fecal coliform bacteria (FC). BTNEP partnered with the South Central Planning and Development Commission to reimburse homeowners for repairing their OSDS in both watersheds. Records show 137 OSDS were repaired or replaced in the B. Folse watershed and 41 in the B. Lafourche watershed through the HSAP. B. Folse data show a decrease in the FC excursions for primary and secondary contact recreation standards when the PI was compared to the POI period. Positive results are attributed to a combination of WM, public education, OSDS inspections, OSDS maintenance training, and the HSAP. [ABSTRACT FROM AUTHOR]

Escherichia coli (E. coli) cells are present in fecal materials that can be the main source for disease‐causing agents in water. As a result, E. coli is recommended as a water quality indicator. We have developed an innovative platform to detect E. coli for monitoring water quality on-site by integrating paper-based sample preparation with nucleic acid isothermal amplification. The platform carries out bacterial lysis and DNA enrichment onto a paper pad through ball-based valves for fluid control, with no need of laboratory equipment, followed by loop-mediated isothermal amplification (LAMP) in a battery-operated coffee mug, and colorimetric detection. We have used the platform to detect E. coli in environmental water samples in about 1 h, with a limit of quantitation of 0.2 CFU/mL, and 3 copies per reaction. The platform was confirmed for detecting multiple E. coli strains, and for water samples of different salt concentrations. We validated the functions of the platform by analyzing recreational water samples collected near the Atlantic Ocean that contain different concentrations of salt and bacteria. [ABSTRACT FROM AUTHOR]

This study explored the effects of H 2 O 2 on Cyanobacteria and non-target microbes using fluorometry, microscopy, flow cytometry, and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY, USA. The addition of H 2 O 2 (8 mg/L) significantly reduced Cyanobacteria concentrations during a majority of experiments (66%; 6 of 9) and significantly increased eukaryotic green and unicellular brown algae in 78% and 45% of experiments, respectively. While heterotrophic bacteria declined significantly following H 2 O 2 addition in all experiments, bacteria indicative of potential fecal contamination (Escherichia coli, Enterococcus , fecal coliform bacteria) consistently and significantly increased in response to H 2 O 2 , evidencing a form of 'pollution swapping'. H 2 O 2 more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem applications. Ten whole-pond H 2 O 2 applications over a two-year period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or less. The bacterial phyla of Cyanobacteria, Actinobacteria, and Planctomycetes were the most negatively impacted by H 2 O 2. Microcystis was always reduced by H 2 O 2 , as was the toxin microcystin, but Microcystis remained dominant even after repeated H 2 O 2 treatments. Although H 2 O 2 favored the growth of eukaryotic algae over potentially harmful Cyanobacteria, the inability of H 2 O 2 to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract—The results of a bacterioplankton study (total abundance; saprophytic, hydrocarbon oxidizing, and phenol resistant bacteria; total microbial count; and coliform bacteria) in an urbanized tributary of Lake Onego in 2015 are presented. The lower reaches of the Lososinka River flow over the territory of the city of Petrozavodsk (Karelia) and receive 14 untreated storm runoff streams from the municipal storm sewers. Differences in the temporal abundance dynamics of bacteria, which are indicators of oil pollution, the sanitary condition, and saprobity, were found between the reference and urban parts of the river. These variations are not related to the hydrological and thermal regime of the river and reflect the impact of the pollutant discharge from the urban area on the formation of the bacterial community of the river. The study revealed a significant increase in all the studied indicators of the quantitative development of bacterioplankton in the urban part of the river as compared to the reference part. The number of heterotrophic bacteria of various ecological–trophic groups decreases in the lake water by a factor of 8–16 already at a distance of 500 m from the mouth of the river due to dilution. A significant decrease in the numbers of hydrocarbon oxidizing bacteria in the river water and an increase in sanitary-indicative microorganisms are shown to have occurred over four years. Within the city limits of Petrozavodsk, the Lososinka River has been assessed as polluted with petroleum products, as well as organic substances of fecal origin and unfit for recreation based on the level of the indicator bacteria. [ABSTRACT FROM AUTHOR]

Coliforms generally are pointer to possible fecal contamination and reflect the hygienic standards of cheese processing. To determine the chemical and microbiological quality of some traditional Egyptian white soft cheese, a total of 200 samples represented by Tallaga, Feta, Baramili and Istamboli (50 samples each) were collected randomly from supermarkets, dairy shops and street-vendors in Giza Governorate, Egypt. Chemically; the averages of pH value and NaCl% in the examined cheese were 6.354, 3.732%; 5.018, 7.0%; 3.441, 6.702% and 4.465, 5.94% for Tallaga, Feta, Baramili and Istamboli cheese, respectively. Microbiologically; Coliforms, faecal Coliforms and Escherichia coli (E.coli) bacteria were detected in 86, 76 and 60% of Tallaga cheese, 64, 54 and 32% of Feta cheese, 88, 68 and 50% of Baramili cheese and 78, 64 and 54% of Istamboli cheese, respectively. The average Coliforms count was 1.3x104, 1.2x10³, 6.5x10³ and 3.6x10³ cfu/g, while, the fecal Coliforms average values were 2.1×10³, 3.1×10², 1.2×10³ and 6.3×10² cfu/g and E.coli average was 2.7x10², 1.8x10², 2.9x10² and 1.2x10² cfu/g for the examined samples, respectively. Serological identifications of the isolated E.coli revealed that 14, 6, 12 and 8% out of all examined cheese samples were pathogenic. The most relevant detected serotypes in cheese were related to enterohemorrhagic (EHEC) and enterotoxigenic (ETEC) strains. Also, enteroinvasive (EIEC) and enteropathogenic (EPEC) related serotypes have been detected in some examined cheese samples. The Coliforms content and incidence of different pathogenic E.coli serotypes reflect the poor hygienic conditions of manufacturing and absence of microbial load elimination. It could be concluded from the obtained results that there is a lack of a standardized method for production and keeping quality of white soft cheese. So, it's suggested to apply strict hygienic measures during all stages of white soft cheese production. [ABSTRACT FROM AUTHOR]

Surface waters are one of the main sources for drinking water production, and thus microbial contamination should be as minimal as possible. However, high concentrations of coliform bacteria were detected in reservoirs and lakes used for drinking water production during summer months due to autochthonous proliferation processes. Here, we present the genomic analyses of 17 strains of Enterobacter asburiae and Lelliottia spp. proliferating in reservoirs and lakes with special focus on the hygienic relevance, antibiotic resistance, and adaptations to the oligotrophic environments. The genomes contain neither genes for the type III secretion system nor cytotoxins or hemolysins, which are considered typical virulence factors. Examination of antibiotic resistance genes revealed mainly efflux pumps and β-lactamase class C (ampC) genes. Phenotypically, single isolates of Enterobacter asburiae showed resistance to fosfomycin and ceftazidime. The genome analyses further suggest adaptations to oligotrophic and changing environmental conditions in reservoirs and lakes, e.g., genes to cope with low nitrate and phosphate levels and the ability to utilize substances released by algae, like amino acids, chitin, alginate, rhamnose, and fucose. This leads to the hypothesis that the proliferation of the coliform bacteria could occur at the end of summer due to algae die-off. IMPORTANCE Certain strains of coliform bacteria have been shown to proliferate in the oligotrophic water of drinking water reservoirs and lakes, reaching values above 104 per 100 mL. Such high concentrations challenge drinking water treatment, and occasionally the respective coliform bacteria have been detected in the treated drinking water. Thus, the question of their hygienic relevance is of high importance for water suppliers and authorities. Our genomic analyses suggest that the strains are not hygienically relevant, as typical virulence factors are absent and antibiotic resistance genes in the genomes most likely are of natural origin. Furthermore, their presence in the water is not related to fecal contamination. The proliferation in reservoirs and lakes during stable summer stratification is an autochthonic process of certain E. asburiae and Lelliottia strains that are well adapted to the surrounding oligotrophic environment. [ABSTRACT FROM AUTHOR]

Feco-orally transmitted infectious diseases are common in Nigeria where the potable water access is poor. In the south-western Nigerian Ibadan metropolis, supply of municipal water is meagre as residents depend on household wells and boreholes. The likelihood of fecal contamination of household water sources in Ibadan was examined longitudinally to quantify and understand its impact. Well and borehole water samples aseptically collected from 96 households in Ibadan were assessed for total heterotrophic counts (THCs), total coliform counts (TCCs) and total Escherichia coli counts (TECs) using a pour plate technique. E. coli were identified by uidA and whole-genome sequencing using Illumina technology, whereas virulence factors were predicted using VirulenceFinder. There was season-independent abundance of THC and TCC in the well and borehole with a significant recovery of E. coli in the wells during the wet season compared to the dry season (P ¼ 0.0001). Virulence genes associated with pathogenic E. coli were identified in 13 (52%) strains with one E. coli each classified as extra-intestinal E. coli, avian pathogenic E. coli and enteroaggregative E. coli. High heterotrophic and coliform counts, with rainfall-driven E. coli contamination revealed that the water sources evaluated in this study are unfit for consumption. [ABSTRACT FROM AUTHOR]

The beaches of Oran are among the busiest in Algeria. However these beaches are exposed to multiple dangers in particular to pollution which poses serious problems and which can also hinder any proper use of the sea. This paper is an assessment of the physico-chemical and bacteriological quality of some beaches where swimming is allowed along the Oranese coast in Algeria, specifically the Kristel Beach and the beach of Les Andalouses seaside resort. Fecal streptococci are normal hosts of the intestine of humans and warm-blooded animals. Research concerning them associated with that of fecal coliforms is a good indication of fecal contamination. Their presence indicates long term contamination of fecal origin while the presence of fecal coliforms indicates a contamination of recent fecal origin. This is why it may become necessary to proceed to the confirmation stage to detect the presence of E. Coli, which is in fact the real indicator sought in this context, through the necessary use of E. Coli specific culture media. The results obtained show a slight difference between the two sites as the beach of Les Andalouses is a bit more polluted compared to that of Kristel. Still, both beaches remain of good quality with regard to national and international standards. [ABSTRACT FROM AUTHOR]

• A validated RT-PCR method targeting 16S ribosomal RNA to qualitatively E. coli in drinking water at a sensitivity of 1 CFU/100 ml. • The method is as sensitive as the reference culture method. • The E. coli RT-PCR showed high interlaboratory reproducibility. • An extensive comparison on practical samples showed good agreement between RT-PCR and the culture method. • Application of the RT-PCR will improve the safety of drinking water consumers. Escherichia coli (E. coli) plays a central role as an indicator for fecal contamination to predict the possible presence of microbial pathogens in drinking water. Current detection methods for E. coli are based on time-consuming culture-based techniques. There is a strong need for methods to detect fecal contamination rapidly in distributed drinking water to prevent outbreaks of waterborne disease and support water utilities to efficiently manage their operations like actions to repair or maintain distribution pipes, to minimize impact on consumers. This study describes the validation and application of a qualitative real time reverse transcription PCR (RT-PCR) method targeting 16S ribosomal RNA (rRNA) for rapid detection of E. coli in distributed drinking water. The RT-PCR assay targets 16S rRNA, a highly abundant RNA in viable cells, enabling robust detection at the required sensitivity of 1 CFU/100 ml. The validation was performed by comparing the RT-PCR method with the culture-based chromogenic reference method (CCA) using the protocol and criteria described in ISO 16,140–2:2016. The validation demonstrated that this RT-PCR method can be used to specifically detect E. coli in a broad range of drinking water samples with at least the same limit of detection as the culture method (Relative Limit Of Detection = 0.75, range 0.43–1.43). The inclusivity study showed that the RT-PCR method was able to detect a broad range of E. coli strains derived from different sources and geographic areas, including pathogenic serotype O157 strains that are not detected with the culture method. The exclusivity study determined that other bacterial genera are not detected with this RT-PCR. However, Escherichia fergusonii was detected and, based on " in silico " analysis, it is expected that also E. albertii and E. marmotae and Shigella species will be detectable using this RT-PCR. An interlaboratory study confirmed that the RT-PCR and culture method have comparable sensitivities when tested by different participants at different laboratories. The application of RT-PCR to confirm the hygienic quality of distributed drinking water after actions to repair or maintain distribution pipes was compared with the culture method on 8076 routine samples, analyzed by the drinking water laboratories in the Netherlands. This comparison study showed a 96.4 % agreement between RT-PCR and culture. In 3.3 % of the samples E. coli was detected with RT-PCR and not with the culture method and in 0.1 % of the samples E. coli was only detected by culture confirming either a higher sensitivity for RT-PCR or the detection of RNA from uncultivable cells. Finally, the application of RT-PCR was highlighted during a contamination event in Belgium where we demonstrate the potency of RT-PCR as a tool to rapidly monitor the spread of microbial contamination and to monitor the effect of measures to remove the contamination This is the first fully validated rapid nucleic based method for detection of E. coli in distributed drinking water. These results demonstrate that this RT-PCR method can be used as a rapid alternative to the culture method to monitor E. coli in distributed drinking water. However, it should be emphasized that nucleic acid based detection methods rely on highly different detection principles (detection of captured nucleic acids present in a sample) than culture base methods (presence of cells cultivable on a selective medium) resulting in occasional different analysis results. Varying treatment and disinfection steps (UV, chlorine, monochloramine, Ozone) or environmental factors (decay) can influence the results and cause differences between RT-PCR and culture methods. [Display omitted] [ABSTRACT FROM AUTHOR]

• Somatic coliphages enhance the assessment of bathing water microbial quality. • Sewer overflows during rainstorms elevates fecal contamination in bathing areas. • Quick and easy determination of water quality recovery after rain events is essential for effective management. • Somatic coliphages exhibit greater persistence in marine waters compared to Escherichia coli and intestinal enterococci. Rapid population growth and coastal development has led to increased fecal contamination of coastal surface waters worldwide, enhancing the potential risk of waterborne human pathogens in bathing areas. More frequent heavy rainfall events, attributed to global warming, have further exacerbated the problem by causing sometimes sewer overflows into recreational waters. As traditional bacterial indicators have limited accuracy for predicting health risks associated with waterborne viruses, the additional use of viral indicators such as coliphages is recommended. In this study, we compared the behavior of bacterial and viral indicators of water quality at 10 Barcelona beaches during three bathing seasons, in dry conditions, and after four rainstorms that caused specific pollution events due to rain runoff with combined sewer overflows (CSO). Levels of all target indicators increased after the rainstorms, but compared to Escherichia coli and intestinal enterococci, somatic coliphages exhibited a slower decline and higher environmental persistence following a rain event. Daily continuous sampling carried out during the days following a rainstorm allowed not only the determination of the decay kinetics of each target indicator but also the day when the water quality recovered the values established in the current European regulation in approximately 2 -3 days after each CSO. These observations indicate that the combined use of bacterial and viral indicators can enhance the surveillance of microbial quality of bathing waters. Moreover, coliphages can swiftly provide insights into transient fecal pollution linked to rainfall episodes, thanks to available analytical techniques that enable same-day recommendations. The management of urban wastewater and recreational water regulations should consistently employ microbial indicators to address rainwater runoff or sewer overflows resulting from heavy rainfall. [Display omitted] [ABSTRACT FROM AUTHOR]

This study presents numerical simulations of fecal coliforms dynamics in Luruaco Lake, located in Atlántico Department, Colombia. The velocity field is obtained through a two-dimensional horizontal (2DH) model of Navier-Stokes equations system. The transport equation of fecal coliforms concentration is provided from a convective-diffusive-reactive equation. The lake's geometry is built through cubic spline and multiblock methods. The discretization method by Finite Differences and the First Order Upwind (FOU) are applied to the 2DH model. The Mark and Cell (MAC) method is used to determine numerically the velocity field of water flow. Numerical simulations are carried out for a 72-h period to understand the influence of fecal coliforms injections from each tributary. From the quantitative analysis of the factors that influence fecal coliforms dynamics, proposals are presented, which aims to reduce contamination of the Luruaco Lake. The numerical simulations show that the best option to improve the water quality of Luruaco Lake is the implementation of two actions, the diversion of the Limón stream to the Negro stream and the installation of a sewage treatment plant at the mouth of the Negro stream. Other less expensive proposals are also presented. [ABSTRACT FROM AUTHOR]

The occurrence of pollution indicator bacteria (total and faecal coliform) has been used as a sanitary parameter for evaluating the quality of drinking water. It is known that these indicators are associated with disease causing organisms which are of great concern to public health. This study assessed the relationship between coliform bacteria and water geochemistry in surface and ground water systems in the Tarkwa mining area using logistic regression models. In surface water sources, higher values of chloride (OR = 0.891, p<005), phosphates (OR = 0.452, p<0.05), pH (OR = 0.174, p<0.05) and zinc (OR = 0.001, p<0.05) were associated with lower odds of faecal coliform contamination. In groundwater sources, higher values of phosphates (OR = 0.043, p<0.001), total dissolved solids (OR = 0.858, p<0.05), turbidity (OR = 0.996, p<0.05) and nickel (OR = 6.09E-07, p<0.05) implied non-contamination by faecal coliform. However, higher values of electrical conductivity (OR = 1.097, p<0.05), nitrates (OR = 1.191, p<0.05) and total suspended solids (OR = 1.023, p<0.05) were associated with higher odds of faecal coliform contamination of groundwater sources. Nitrates and total suspended solids, in this case, were completely mediated by the heavy metals. For total coliform in surface water systems, higher values of magnesium (OR = 1.070, p<0.05) was associated with higher odds of total coliform contamination while higher values of phosphates (OR = 0.968, p<0.05) was associated with lower odds of total coliform contamination although the presence of heavy metals completely mediated these relationships. For ground water systems, higher values of pH (OR = 0.083, p<0.05), phosphates (OR = 0.092, p<0.05), turbidity (OR = 0.950, p<0.05) and chloride (OR = 0.860, p<0.05) were associated with lower odds of total coliform contamination. However, higher values of total suspended solids (OR = 1.054, p<0.05) and nitrates (OR = 1.069, p<0.05) implied contamination of total coliform in ground water sources. The relationship between nitrates and total coliform were mediated by the heavy metals. This study establishes the need to monitor, manage and remediate surface and ground water sources for potential disease causing microbes in ways that takes into consideration the factors that create different conditions in the two water systems. This study validates the usefulness of statistical models as tools for preventing surface and ground water contamination. [ABSTRACT FROM AUTHOR]

Background and Aim: Bacterial contamination of drinking water is a leading cause of gastrointestinal infections. Cats may be at risk of water contamination from feces due to poor sanitation and hygiene. The objectives of the present study were to (1) evaluate the prevalence of coliform bacteria in cat drinking water and (2) identify possible risk factors leading to contamination. Materials and Methods: Fifty-five drinking water samples were collected from water containers used by cats (median age [range]: 5 years [8 months-15 years]) at their home. Using a sterile syringe, 50 mL water was collected directly from water containers. The water samples were stored in coliform enhancement media for 24 h and then submitted for bacterial culture. Results: The prevalence of fecal coliform contamination of cat drinking water was 67.27% (37/55; 95% confidence interval: 53.29-79.32%). There was no significant difference in the prevalence of coliform bacterial contamination of drinking water by age or gender of the cat or by water container type. However, bacterial contamination differed significantly between shorthaired cats and longhaired cats when comparing Escherichia coli (9/44 [20.45%] vs. 8/11 [72.72%], p<0.001) and Enterobacter spp. (16/44 [36.36%] vs. 9/11 [81.82%], p=0.007). For water that had been in a container longer than 12 h, there were significantly more contaminated tap water samples (16/19 [84.21%]) than contaminated processed water samples (9/17 [52.94%], p=0.047). Conclusion: Coliform contamination in cat drinking water is common and occurs more often in households with longhaired cats. Drinking water for cats should be changed every 12 h, especially for households using tap water. [ABSTRACT FROM AUTHOR]

In the European Union, recreational water quality is regulated by the bathing water directive, which requires authorities to regularly take water samples to identify fecal bacterial pollution, which can compromise the bathing water quality at designated recreational bathing water areas. Using a case study from Lake Knudsøin Denmark, this paper shows that the bathing water quality occasionally is compromised by overflows from combined sewer systems. Due to the randomness in the frequency of overflow occurrences, the entailing decrease in bathing water quality is not normally detected by the regulatory sampling campaigns. By dedicated sampling campaigns conducted in this project in the proximity of outlets and recreational bathing areas and by hydrodynamical transport modeling, it is shown that the transport patterns of pollutants are crucially and rapidly dependent on dynamic conditions. The occasional short-term pollution by fecal bacteria and consequent decrease in bathing water quality are, therefore, challenging to capture (both spatially and temporally) by regular water sampling. Rather than increasing the frequency of water sampling, an online model-based warning system for fecal bacteria contamination in bathing areas is proposed. This warning system framework includes: (1) dynamical modeling of combined sewer overflow based on rainfall over a catchment area, (2) a hydrodynamical model that simulates current fields in multiple vertical layers based on wind forcing and water fluxes, and (3) a particle dispersion model which provides an estimate of pollutant concentrations. The output from the model has shown potential to issue bathing prohibition if there is a risk of fecal bacteria concentrations below the criteria for good bathing water quality. [Display omitted] • Regular sampling for fecal bacteria does not capture occasional pollution from CSOs. • Dispersion of coliforms is modeled in a lake affected by stratification and wind shear. • A predictive online warning system for bathing water quality is proposed. [ABSTRACT FROM AUTHOR]

The identification and quantification of viable Escherichia coli (E. coli) are important in multiple fields including the development of antimicrobial materials, water quality, food safety and infections diagnosis. However, the standard culture-based methods of viable E. coli detection suffer from long detection times (24 h) and complex operation, leaving the unmet requirement for fast assessing the efficiency of antimicrobial materials, early alerting the contamination of water and food, and immediately treatment of infections. We present a digital β- d -glucuronidase (GUS) assay in a self-priming polydimethylsiloxane (PDMS) microfluidic chip for rapid E. coli identification and quantification. The GUS expression in viable bacteria was investigated to develop a fast GUS assay at the single-cell level. Single E. coli were stochastically discretized in picoliter chambers and identified by specific GUS activity. The digital GUS assay enabled identifying E. coli within 3 h and quantifying within 4 h for different E. coli subtypes. The specificity of our method was confirmed by using blended bacteria including E. coli, Bacillus , Shigella and Vibrio. We utilized digital GUS assay to enumerate viable E. coli after incubated with antibacterial materials for assessing the antibacterial efficiency. Moreover, the degassed chip can realize automatic sample distribution without external instruments. The results demonstrated the functionality and practicability of digital GUS assay for single E. coli identification and quantification. With air-tight packaging, the developed chip has the potential for on-site E. coli analysis and could be deployed for diagnosis of E. coli infections, antimicrobial susceptibility testing, and warning the fecal pollution of water. Digital GUS assay provides a paradigm, examining the activity of metabolic enzyme, for detecting the viable bacteria other than E. coli. [Display omitted] • A self-dispensing microwell array chip was developed. • Digital GUS assay enabled to differentiate viable E. coli. • E. coli identification and quantification was achieved in 4 h. • The bactericidal efficiency of 2D materials was assessed with digital GUS assay. [ABSTRACT FROM AUTHOR]

Water is important for our survival and indispensable for the production of food and other activities for economic purposes. The necessary characteristic of the water distributed for human consumption is potability, that is, it must be clean and free from any contamination of microbiological, chemical, physical or radioactive origin, and under no circumstances should it offer risks to human health. The objective was to evaluate the microbiological quality of water in the city of Muritiba, Bahia. Twelve water samples were collected at different points: a Cachoeirinha river and where in Muritiba. Microbiological analyzes were performed according to the methodological procedures described in the Practical Water Analysis Manual. Through the analyzes carried out it was possible to assess whether there was the presence or absence of bacteria in the coliform group; of the twelve points evaluated, the eleven collected in the city of Muritiba, resulted in the absence of microorganisms, while that of the Cachoeirinha River, had presence of both microorganisms, being unfit for consumption. Thus, water and / or reservoir care is necessary to make quality water available to the population. [ABSTRACT FROM AUTHOR]

The present study was designed to analyse the microbiological quality of groundwater in open-defaecation-free (ODF) villages of the Kurukshetra district in Haryana. Twenty-seven groundwater samples were collected from borewells of nine ODF villages located in three different blocks of the Kurukshetra district in three seasons and analysed for total and faecal coliform count. The presence of gram-negative, rod-shaped bacteria was observed in all the groundwater samples and the dominating genera found were Klebsiella sp. All strains were found to be resistant to clindamycin (100%) followed by gentamicin (66.6%), azithromycin and streptomycin (50%) and chloramphenicol (33.3 %) antibiotics. Minimum resistance of isolates was observed for antibiotic norfloxacin, ciprofloxacin (16.66%) and zero resistance were observed against tetracycline. The Multiple Antibiotic Resistance (MAR) index values indicated that in a majority of the samples (66.6%), the source of contamination was non-human, but nearly 33.3% were found to be contaminated by some human sources. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to reveal the importance of microbiological factors in water quality determination studies based on fuzzy logic and to determine the usability of management in water quality. Six critical parameters for water quality detection are included. In the study of Avsar [1], only bacteriological data were emphasized, and no information was obtained about quantitative data on water quality. It was found that fecal coliform was more effective on the changes in water quality compared to fecal coliform and temperature based fuzzy quality indexes. When the fuzzy quality values were determined, the effect of seasonal changes did not appear to be high, but the change in pH and coliform values affected the quality. This showed that water quality assessment would not be accurate without microbiological data. As a result, the proposed data can be considered accurate and reliable, so we recommend that microbiological data should be included in the evaluation of water quality determination studies. In addition, we can say that fuzzy logic technique will be a comprehensive and reliable technique in the assessment of the quality of the streams that are used in irrigation, fishing and recreational areas. [ABSTRACT FROM AUTHOR]

In this study, microbial quality of the peskütan yoghurt which is a concentrated yoghurt type produced by traditional methods and sold in Sivas province public markets was assessed. For this purpose, 30 peskütan samples were collected from Sivas center and districts and microbiological analysis were performed according to the International Organization for Standardization (ISO) methods. The analysis aerobic bacteria (TAMB), yeast-mould, coliform group bacteria, Escherichia coli and coagulase-positive Staphylococci counts. Besides these bacterial groups, Listeria monocytogenes and Salmonella spp. were also counted in samples. As a result of the analysis, TAMB and yeast-mould counts in the samples were found 6.74±0.66 and 7.11±1.10 log kob g-1 respectively. In none of the samples, coliform group bacteria, E. coli, Salmonella spp. and L. monocytogenes species were not detected. In the counting of Staphylococci, 19 of the 30 samples were determined as Staphylococcus spp. but none of them were identified as coagulase positive S. aureus. The results obtained indicate that there are no pathogenic microorganisms or fecal contamination in the peskütan samples. However, the high number of TAMB and yeast-mold in peskütan samples may indicate that hygienic conditions are not sufficiently at the production, storage or marketing stages. [ABSTRACT FROM AUTHOR]

Contamination of drinking and surface waters with microorganisms is a problem that attracts attention because it threatens human health. One of the microorganisms that determine fecal contamination in water is a bacteriophage that infects coliform bacteria. A fast, real-time, sensitive, and low-cost alternative method is the nanosensor system for microorganism detection. This study aimed to develop a surface plasmon resonance nanosensor for the detection of T4 bacteriophages using nanoparticle- and nanofilm-based polymers. In this context, nanoparticle and nanofilm-based imprinted polymers were synthesized to develop nanosensors, and their efficacy was compared in fecal pollution determination in water. Following the characterization studies, nanoparticle and nanofilm-based plasmonic nanosensors were used to carry out kinetic studies in the 1 × 104–4 × 106 pfu mL−1 concentration range in buffer, sea, and tap water sample solutions. Reusability and selectivity studies were also performed. According to the results, the nanoparticle and nanofilm-based plasmonic nanosensors could measure with 98% and 81% precision, respectively. The limit of detection values was calculated as 6 × 103 pfu mL−1 and 8 × 103 pfu mL−1 for the nanoparticle and the nanofilm-based plasmonic nanosensors, respectively. In addition, the recovery value of the nanoparticle-based plasmonic nanosensor was calculated as 91–96%, while the nanofilm-based plasmonic nanosensor was calculated as 85–90% in tap and seawater samples. All results showed that both plasmonic nanosensors could detect with high selectivity, but the nanoparticle-based plasmonic nanosensor has higher sensitivity than the nanofilm-based plasmonic nanosensor. [ABSTRACT FROM AUTHOR]

As climate change continues to stress freshwater resources, we have a pressing need to identify alternative (non-traditional) sources of microbially safe water for irrigation of fresh produce. This study is part of the center CONSERVE, which aims to facilitate the adoption of adequate agricultural water sources. A 26-month longitudinal study was conducted at 11 sites to assess the prevalence of bacteria indicating water quality, fecal contamination and crop contamination risk (Escherichia coli, total coliforms (TC), Enterococcus, Aeromonas). Sites included non-tidal freshwater rivers/creeks (NF), a tidal brackish river (TB), irrigation ponds (PW) and reclaimed water sites (RW). Water samples were filtered for bacterial quantification. E. coli, TC and enterococci (~86%, 98% and 90% positive, respectively; n=333), and Aeromonas (~98% positive; n=133) were widespread in water samples tested. Highest E. coli counts were in rivers, TC counts in TB rivers and enterococci in rivers and ponds (all p<0.001), compared to other water types. Aeromonas counts were consistent across sites. Seasonal dynamics were detected in NF and PW samples only. E. coli counts were higher in the vegetable crop-growing (May- October) than non-growing (November-April) season in all water types (p<0.05). Only one RW and both PW sites met the US Food Safety Modernization Act water standards. However, implementation of recommended mitigation measures of allowing time for microbial die-off between irrigation and harvest would bring all other sites into compliance within two days. This study provides comprehensive microbial data on alternative irrigation water and serves as an important resource for food safety planning and policy-setting. [ABSTRACT FROM AUTHOR]

Various methods have been developed to detect the presence of contamination with Coliforms and E. coli in foods. The pour plate technique using VRBA medium is confirmed as a standard method in Iran. The biggest disadvantage of thismethod is the need to spend a lot of time, high volume of laboratory operations, multiple stages and ultimately long time to achieve the results. Today, due to the mass productionof various foodstuffs, the need for faster methods with high sensitivity to control the quality of food is necessary for the responsible oversight centers. The use of chromogenic medias is also one of the fastest diagnostic methods that have been developed. According to this matter,a comparative study was considered from the results of application of three chromogenic media and reference method in food quality control. Totally 100 samples of foodstuffs were evaluated for contamination to Coliform and E.coli using standard method and three chromogenic medias. Based on the obtained results, 86, 79, 85 and 80 samples were contaminated to Coliform using the standard method, Coliform Agar ES, ChromAgar ECC and Rapid E.coli 2/Agar respectively. Also, using four mentioned methods, contamination to E.coli was reported at 66, 80, 84 and 80, respectively. Cochrane test showed that there was no significant difference between the four methods in Coliform diagnosis (p>0.05). However, four methods did not have the same function in the detection of E. coli so that the chromogenic methods showed significant difference with the standard method (p< 0/001). But there was no significant difference between these chromogenic methods in detecting E.coli (p>0.05). According to the statistical analysis of present study, three chromogenic medias can be used instead of the standard method for the detection of Coliform, but the use of these chromogenic medias is not recommended for the identification of E.coli. [ABSTRACT FROM AUTHOR]

The microbiological contamination of the water with faecal bacteria resulting from anthropogenic activity is an important issue for population health and the assessment of the presence of pathogenic bacteria in the water is a major concern for the protection of humans and animals. Coliform bacteria are indicators for the assessment of faecal pollution and a potential presence of pathogens, which is caused mainly by untreated wastewater. In this paper, a comparative study was carried out in 32 sampling sites of MONITOX network in two periods, June 2019 and June-July 2020, before and after COVID-19 pandemic lockdown, regarding the rate of the water microbiological contamination in Lower Danube (Calarasi/Silistra-Galati-Tulcea sectors, Danube Delta and the Black Sea coast, from the SE part of Romania, by counting of the bacteria indicators of the organic pollution (heterotrophic bacteria and total coliforms). The results demonstrate a decrease of microbiological contamination of surface water in 2020 during the COVID-19 lockdown in all the samples collected from the Black Sea coast, Danube branches, Danube-Black Sea confluence, and Danube river downwards the town of Galati. [ABSTRACT FROM AUTHOR]

Escherichia coli is mostly a commensal of birds and mammals, including humans, where it can act as an opportunistic pathogen. It is also found in water and sediments. We investigated the phylogeny, genetic diversification, and habitat-association of 1,294 isolates representative of the phylogenetic diversity of more than 5,000 isolates from the Australian continent. Since many previous studies focused on clinical isolates, we investigated mostly other isolates originating from humans, poultry, wild animals and water. These strains represent the species genetic diversity and reveal widespread associations between phylogroups and isolation sources. The analysis of strains from the same sequence types revealed very rapid change of gene repertoires in the very early stages of divergence, driven by the acquisition of many different types of mobile genetic elements. These elements also lead to rapid variations in genome size, even if few of their genes rise to high frequency in the species. Variations in genome size are associated with phylogroup and isolation sources, but the latter determine the number of MGEs, a marker of recent transfer, suggesting that gene flow reinforces the association of certain genetic backgrounds with specific habitats. After a while, the divergence of gene repertoires becomes linear with phylogenetic distance, presumably reflecting the continuous turnover of mobile element and the occasional acquisition of adaptive genes. Surprisingly, the phylogroups with smallest genomes have the highest rates of gene repertoire diversification and fewer but more diverse mobile genetic elements. This suggests that smaller genomes are associated with higher, not lower, turnover of genetic information. Many of these genomes are from freshwater isolates and have peculiar traits, including a specific capsule, suggesting adaptation to this environment. Altogether, these data contribute to explain why epidemiological clones tend to emerge from specific phylogenetic groups in the presence of pervasive horizontal gene transfer across the species. Author summary: Previous large scale studies on the evolution of E. coli focused on clinical isolates emphasizing virulence and antibiotic resistance in medically important lineages. Yet, most E. coli strains are either human commensals or not associated with humans at all. Here, we analyzed a large collection of non-clinical isolates of the species to assess the mechanisms of gene repertoire diversification in the light of isolation sources and phylogeny. We show that gene repertoires evolve so rapidly by the high turnover of mobile genetic elements that epidemiologically indistinguishable strains can be phenotypically extremely heterogeneous, illustrating the velocity of bacterial adaptation and the importance of accounting for the information on the whole genome at the epidemiological scale. Phylogeny and habitat shape the genetic diversification of E. coli to similar extents. Surprisingly, freshwater strains seem specifically adapted to this environment, breaking the paradigm that E. coli environmental isolates are systematically fecal contaminations. As a consequence, the evolution of this species is also shaped by environmental habitats, and it may diversify by acquiring genes and mobile elements from environmental bacteria (and not just from gut bacteria). This may facilitate the acquisition of virulence factors and antibiotic resistance in the strains that become pathogenic. [ABSTRACT FROM AUTHOR]

This research focused on the quality of domestic water in Bangolan, Northwest Cameroon, in order to ascertain its potability based on World Health Organisation (WHO) guidelines. Inhabitants of this locality, as well as others in rural areas, consume water from these sources without any prior treatment which can lead to contamination and infections. Sampling was conducted, and physicochemical and bacteriological properties of ten water sources were examined in November 2017 and January, April, and July 2018 using standard methods. The results showed that the sampled water sources were moderately acidic to weakly basic falling within the WHO specification. The values of electrical conductivity and total dissolved solids were low, suggesting low mineralised waters which could lead to a shortage of essential mineral elements in humans. Water turbidity was high in July, attributable to the rains. Major ions analysed fell within the WHO guideline values except iron and aluminium, whose values fell above guideline values in both seasons due to the nature of the soils. Faecal coliforms were found in all the sources, and specific bacteria identified were Escherichia coli, Enterobacteria, Streptococcus, Salmonella, and Shigella spp., suggesting recent contamination by faecal matter due to poor hygienic conditions, and hence, treatment was recommended. Statistical analyses revealed significant influence of heavy rains on most water parameters (p < 0.05). Health data in the locality revealed 1389 cases of water-borne diseases, namely, typhoid, diarrhoea, and dysentery between 2016 and 2017 necessitating control. [ABSTRACT FROM AUTHOR]

Anticipated future hydroclimatic changes are expected to alter the transport and survival of fecally sourced waterborne pathogens, presenting an increased risk of recreational water quality impairments. Managing future risk requires an understanding of the interactions between fecal sources, hydroclimatic conditions, and best management practices (BMPs) at spatial scales relevant to decision makers. In this study, we used the Hydrologic Simulation Program FORTRAN (HSPF) to quantify potential fecal coliform (FC, an indicator of the potential presence of pathogens) responses to a range of mid-century climate scenarios and assess different BMP scenarios (based on reduction factors) for reducing the risk of water quality impairment in two small agricultural watersheds: the Chippewa watershed in Minnesota, and the Tye watershed in Virginia. In each watershed, simulations show a wide range of FC responses, driven largely by variability in projected future precipitation. Wetter future conditions, which drive more transport from nonpoint sources (e.g., manure application, livestock grazing), show increases in FC loads. Loads typically decrease in drier futures; however, higher mean FC concentrations and more recreational water quality criteria exceedances occur, likely caused by reduced flow during low-flow periods. Median changes across the ensemble generally show increases in FC load. BMPs that focus on key fecal sources (e.g., runoff from pasture, livestock defecation in streams) within a watershed can mitigate the effects of hydroclimatic change on FC loads. However, more extensive BMP implementation or improved BMP efficiency (i.e., higher FC reductions) may be needed to fully offset increases in FC load and meet water quality goals, such as total maximum daily loads and recreational water quality standards. Strategies for managing climate risk should be flexible and to the extent possible include resilient BMPs that function as designed under a range of future conditions. [ABSTRACT FROM AUTHOR]

Microbial source tracking and a mass balance approach were used to identify sources of fecal indicator bacteria (FIB) in the Hanalei River, Kaua'i, Hawai'i. Historically, concentrations enterococci and Clostridium perfringens were significantly higher during storm flows compared to non-storm flows in the Hanalei River, and correlated to total suspended solids in the river. During targeted dry weather studies, the Hanalei River bed sediments and streambank soils were documented to harbor E. coli, enterococci, and the human- and pig-specific fecal markers in Bacteroidales, suggesting that sediments and soils may be potential sources of these microorganisms to the Hanalei river. The human-specific marker in Bacteroidales was four times as likely to be detected in sediment and soil samples as in water samples. Furthermore, the occurrence of host-specific source tracking markers is indicative that a portion of FIB present in the Hanalei River are of fecal origin. A mass balance approach was used to explore causes of observed FIB loadings and losses along different reaches of the river. Resuspension or deposition of FIB-laden river sediments cannot account for changes in E. coli and enterococci concentrations along the river during dry weather. Additionally, losses due to bacterial inactivation were insignificant. Groundwater and ditches draining agricultural and urban lands were shown to provide sufficient FIB fluxes to account for the observed loads along some river reaches. The presence of the human-specific Bacteroidales marker in the river water, sediments and adjacent soils, as well as the presence of the human enterovirus marker in the water, suggests that there is widespread human fecal contamination in the Hanalei River that is likely a result of nearby wastewater disposal systems. [ABSTRACT FROM AUTHOR]

Antibiotic-resistant bacteria represent an emerging global health problem and are frequently detected in riverine environments. Analyzing the occurrence of corresponding antibiotic-resistant genes in rivers is of public interest as it contributes towards understanding the origin and dissemination of these emerging microbial contaminants via surface water. This is critical for devising strategies to mitigate the spread of resistances in the environment. Concentrations of blaCTX-M antibiotic resistance genes were quantified weekly over a 12-month period in Lahn River surface water at two sampling sites using quantitative real-time PCR. Gene abundances were statistically assessed with regard to previously determined concentrations of fecal indicator organisms Escherichia coli, intestinal enterococci and somatic coliphages, as well as influential environmental factors. Similar seasonal patterns and strong positive correlations between fecal indicators and blaCTX-M genes indicated identical sources. Accordingly, linear regression analyses showed that blaCTX-M concentrations could largely be explained by fecal pollution. E. coli provided the best estimates (75% explained variance) at the upstream site, where proportions of blaCTX-M genes in relation to fecal indicator organisms were highest. At this site, rainfall proved to be more influential, hinting at surface runoff as an emission source. The level of agricultural impact increased from downstream to upstream, linking increasing blaCTX-M concentrations after rainfall events to the degree of agricultural land use. Exposure assessment revealed that even participants in non-swimming recreational activities were at risk of incidentally ingesting blaCTX-M genes and thus potentially antibiotic resistant bacteria. Considering that blaCTX-M genes are ubiquitous in Lahn River and participants in bathing and non-bathing water sports are at risk of exposure, results highlight the importance of microbial water quality monitoring with an emphasis on antibiotic resistance not only in designated bathing waters. Moreover, E. coli might serve as a suitable estimate for the presence of respective antibiotic resistant strains. [ABSTRACT FROM AUTHOR]

To correctly assess and properly manage the public health risks associated with exposure to contaminated water, it is necessary to identify the source of fecal pollution in a watershed. In this study, we evaluated the efficacy of our two previously developed real time-quantitative PCR (qPCR) assays for the detection of swine-associated Bacteroidales genetic markers (gene 1–38, gene 3–53) in the Yangtze Delta watershed of southeastern China. The results indicated that the gene 1–38 and 3-53 markers exhibited high accuracy (92.5%, 91.7% conditional probability, respectively) in detecting Bacteroidales spp. in water samples. According to binary logistic regression (BLR), these two swine-associated markers were well correlated (P < 0.05) with fecal indicators (Escherichia coli and Enterococci spp.) and zoonotic pathogens (E. coli O157: H7, Salmonella spp. and Campylobacter spp.) in water samples. In contrast, concentrations of conventional fecal indicator bacteria (FIB) were not correlated with zoonotic pathogens, suggesting that they are noneffective at detecting fecal pollution events. Collectively, the results obtained in this study demonstrated that a swine-targeted qPCR assay based on two Bacteroidales genes markers (gene 1–38, gene 3–53) could be a useful tool in determining the swine-associated impacts of fecal contamination in a watershed. Image 1 [ABSTRACT FROM AUTHOR]

Objective: Şanlıurfa city center and its districts were exposed to demographic high population movements with starting of the Southeastern Anatolia Project (GAP). Moreover, with the influence of refugees from Syria, it faced population pressure over the projected future population projections. One of the most significant effects of this population pressure from the perspective of infrastructure and environment has been the inability to successfully provide a healthy water supply system. In this study, it is aimed to demonstrate the effects of environmental pressure and changes in drinking-usage water quality. Siverek District was chosen as the largest district (4314 km2 area; 2018 population total 258.265 people; center 146.131 people) in terms of representing the thirteen districts in the province. Methods: The drinking-usage water system (water resources, reservoirs, and water networks) of the district was examined. Between January 2018 - September 2018, water samples were taken from nine sampling points seasonally under the "Water Sample Acceptance Criteria" published by the General Directorate of Public Health in 2018. 500 mL sterile sodium thiosulfate bottles were used for microbiological samples and 1.5 L polyethylene bottles were used for chemical anaylsis. Coliform bacteria, Escherichia coli (E. coli) and enterococci analysis were carried out by the membrane filtration method. Temperature, electrical conductivity, pH and free chlorine were measured as in situ. Fluoride, ammonium, nitrite, nitrate, sulfate, chloride as spectrophotometric; trihalomethanes, calcium, magnesium, sodium, potassium and iron parameters were made with ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometry) using EPA (United States Environmental Protection Agency) 200.7 method. Results: According to the results of the analysis, it has been determined that the physicochemical parameters, excluding free chlorine, are in the appropriate range according to the criteria for "Regulation on Waters for Humanitarian Consumption (ITASHY)". In terms of microbiological parameters, significant inappropriate values were determined especially in the summer and fall seasons. In the microbiological analysis, coliform bacteria were detected in 15 samples (42%), E. coli were detected in nine samples (25%) and enterococci were detected in three samples (0.8%). Conclusion: With the ongoing activities of the GAP, Sanliurfa and its districts have received a significant level of immigration from surrounding districts. This situation has also resulted in increased migration from rural areas to urban centers. Furthermore, following the Syrian civil war, Sanliurfa province has received the greatest impact of refugees in Turkey. This, in turn, had a negative effect on the management of transport, infrastructure, health, and the environment. [ABSTRACT FROM AUTHOR]

To satisfy the regulations for water supply suitable for human consumption is one of the main objectives of the drinking water treatment plants. The above, given the pollution of the supply sources and the climatic changes that put at risk the components of the system in general. This paper analyzes the turbidity as an indicator parameter of the purification process in a municipal plant, by determining the level of correlation that the turbidity shows with other parameters and according to historical records between the years 2011 and 2015. Thus, by sampling and testing the influent and effluent that is periodically performed for the plant to measure the water quality supplied to the community it is possible to determine the levels of the water quality parameters, and the Pearson's linear correlation coefficients are also calculated between these. In conclusion, turbidity shows a significant positive linear correlation with fecal coliforms (r = 0.70), total coliforms (r = 0.40), and apparent color (r = 0.40). Additionally, turbidity and fecal coliforms show the best correlations, offering two linear regression models for the forecast of each variable. [ABSTRACT FROM AUTHOR]

Sources of water at Oke - Ose, Abantan and Idi - Igba communities in Ilorin, Kwara, Nigeria were evaluated for potability. A total of 21 wells and 6 boreholes were sampled in these communities. The sanitary survey, total viable bacterial count, total coliform and faecal coliform counts as well as some physicochemical parameters of the water were assessed. The total viable bacterial counts of the well water and the borehole water ranged from 0.4 x 102 - 3.8 x 102 CFU/mL and 0.5 × 10? - 1.4 × 102 CFU/mL respectively. Furthermore, the range of total coliform counts of the well water and borehole water were 3 - 150 MPN/100ml and 3 - 28 MPN/100 mL respectively. Faecal coliform was not isolated in all the water samples. Only 50% and 42.9% of the boreholes and wells had sanitary score of less than 80%. All the water samples were within the limit of the physicochemical parameters allowed by Nigerian standard for drinking water quality (NSDWQ) for turbidity, total solid, dissolved solid, chloride, nitrate, and electrical conductivity. All the water samples did not meet up with the permissible limit of 100mg/l of sulphate. The bacteria isolated in this study include Budvicia aquatica, Enterobacter agglomerans, Myroides odoratus, Burkholderia cepacia, Pseudomonas aeruginosa, Aeromonas hydrophila, Listeria sp. and Corynebacterium sp. It was concluded from this study that 19.0% of the wells water and 16.7% of the borehole water supplies satisfied bacteriological qualities of potable water. It is recommended that the resident of these communities need to be enlightened on the need for hygienic environment and measures of protecting their water supplies from contamination. [ABSTRACT FROM AUTHOR]

Low-cost natural wastewater treatment technologies are very useful in developing communities that lacks investment and technologies. Wetland technologies prove excellent results for wastewater treatment. The objective of this study is to compare and propose a new wastewater technologies using wetland, weirs as an aeration source, finally add Mouringa Oleifera seeds which proven effective in removing: suspended substances, turbidity, chemical oxygen demand (COD), color, and other organic pollutants. To cover the objectives, several studies have been carried out, and can be summarized as follows: two study areas were investigated that used instream wetland as a natural treatment and compare the hydraulic design and efficiency for two case studies both in Egyptian drainage systems. Secondly, studied a field aeration weir that already exists in one of the rural drains and studied its ability to improve water quality after aeration system, finally represent a laboratory analysis using Mouringa Oleifera seeds for drainage water treatment. Removal efficiency for the first wetland study area ranged from 35% to 75% for removal of suspended solids, from 58% to 30% for BOD, 57–44% for COD, and 99% for fecal coliform. While in the second instream wetland is 50% for EC, 83.33 for bicarbonate, 44.2% for TDS, 20% for TSS, 60% for BOD, 85% for COD, 63% for calcium, 88% for potassium, 20% for magnesium, 90% for lead, 99% for total and fecal coliform. The removal efficiency when using M. Oleifera is 85.1% for turbidity, 96.1% for total coliform, 82.8% for total coliform, 60% for arsenic, 85% for cadmium, and 90% for nickel. The efficiency for weir as an aeration source is 77.1% for EC, 98% for TDS, 92.9 for bicarbonate, 95.8% for chloride, and 83.3% for phosphate. The studied technologies offer a cheaper alternative to conventional treatment methods without using any chemical substances for treatment and provide minimum operation and maintenance needs. The instream wetland could be replicated to cover a larger percentage of drains recommend using M. Oleifera beside native plants in wetland especially in sedimentation zone, also study weirs as an aeration source. [ABSTRACT FROM AUTHOR]

A genetic algorithm (GA)-based water quality model is built to predict fecal coliform from five independent factors, namely two-day cumulative precipitation, temperature, urban, forest, and agricultural land use factors. The current work succeeds the previous work of the corresponding author which studied the relationship between fecal coliform and the five factors using artificial neural networks and GIS for a watershed consisting of Green River in Kentucky, USA. In the current paper, the main idea is to develop the hyper-parameters (center and radius) of the radial basis function (RBF) neural network from a GA. A GA is one of the nature-inspired evolutionary algorithms, which is an iterative one and successful in solving many optimization problems. Genetic algorithms are generally used for finding the maxima or minima from a given set of population members. They can also be used to tune the hyper-parameters which are found in the current paper for application in water quality (or fecal coliform) modeling using RBF neural networks. The predicted result using GA-based RBF neural networks is found to be slightly better than without using GAs. [ABSTRACT FROM AUTHOR]