Fecal Contamination Research Articles

Quantitative source apportionment of faecal indicator bacteria from anthropogenic and zoogenic sources of faecal contamination

Recreational bathing waters are complex systems with diverse inputs from multiple anthropogenic and zoogenic sources of faecal contamination. Faecal contamination is a substantial threat to water quality and public health. Here we present a comprehensive strategy to estimate the contribution of faecal indicator bacteria (FIB) from different biological sources on two at-risk beaches in Dublin, Ireland. The daily FIB loading rate was determined for three sources of contamination: a sewage-impacted urban stream, dog and wild bird fouling. This comparative analysis determined that the stream contributed the highest daily levels of FIB, followed by dog fouling. Dog fouling may be a significant source of FIB, contributing approximately 20 % of E. coli under certain conditions, whereas wild bird fouling contributed a negligible proportion of FIB (<3 %). This study demonstrates that source-specific quantitative microbial source apportionment (QMSA) strategies are vital to identify primary public health risks and target interventions to mitigate faecal contamination.

Septage treatment using the First Stage of French Vertical Flow Constructed Wetlands: From the beginning to the closure of the system

The First Stage of French Vertical Flow Constructed Wetlands (FS-FVFCW) offers a sustainable solution for treating septage. The system operates through distinct phases: start-up, full operation and final rest. During full operation, factors such as feeding duration, rest periods and percolate impounding significantly affect performance. This study assessed the performance of a pilot-scale Modified FS-FVFCW in Northern Tropical Andes, from start-up to closure stages under three operational scenarios. These scenarios varied in planted/unplanted conditions and percolate drainage/impounding. A four-month start-up phase proved adequate for vegetation growth and adaptation, achieving over 50% COD removal efficiency. Percolate retention (impounding) during operation notably improved COD and TS removal, increasing efficiencies from 49% to approximately 90% for COD and from 39% to around 70% for TS. Plant presence contributed to mosquito control and odour reduction but had minimal impact on removal efficiencies. The pilot demonstrated significant dewatering potential, with sludge deposit samples showing water content below 76% across all scenarios after 24 h; and a 10% reduction in VS/TS ratio during the operational resting period. After a 5-month closure, the sludge deposit layer exhibited organic matter content similar to long-rested sludge, albeit with persistent faecal contamination.

Comparative experiment to select water quality parameters for modelling the survival of Escherichia coli in lakes

Numerical health risk assessment models have been developed to describe faecal contamination of water using Escherichia coli as an indicator bacterium. Although many previously established numerical models for E. coli in aquatic environments have only considered the effects of one or two water quality parameters such as temperature and sunlight, it is difficult to simulate E. coli survival with only one or two parameters because the aquatic environment is a complex system. This study conducted a series of comparative experiments to select water quality parameters that should be preferentially considered in a numerical model for E. coli survival in lakes. The parameters considered were temperature, pH, dissolved oxygen (DO), total dissolved solids (TDS), suspended solids (SS), coexisting microbes, and light intensity. In the laboratory experiments, the survival of E. coli was observed by controlling two of these seven parameters, and the effects of these parameters on the rate of E. coli population change were statistically compared. Consequently, light intensity affected the survival of E. coli most significantly, followed by the presence of coexisting microbes, temperature, pH, and TDS. However, DO and SS had smaller effects on survival than other parameters. High-impact interactions on E. coli survival were observed between temperature and TDS and temperature and coexisting microbes. These results suggest that existing numerical models for simulating E. coli survival in lakes should be modified to consider the independent and interactive effects of multiple parameters such as sunlight, coexisting microbes, temperature, pH, and TDS.

A multi-tiered approach to assess fecal pollution in an urban watershed: Bacterial and viral indicators and sediment microbial communities

Development of effective pollution mitigation strategies require an understanding of the pollution sources and factors influencing fecal pollution loading. Fecal contamination of Turkey Creek in Gulfport, Mississippi, one of the nation's most endangered creeks, was studied through a multi-tiered approach. Over a period of approximately two years, four stations across the watershed were analyzed for nutrients, enumeration of E. coli, male-specific coliphages and bioinformatic analysis of sediment microbial communities. The results demonstrated that two stations, one adjacent to a lift station and one just upstream from the wastewater-treatment plant, were the most impacted. The station adjacent to land containing a few livestock was the least impaired. While genotyping of male-specific coliphage viruses generally revealed a mixed viral signature (human and other animals), fecal contamination at the station near the wastewater treatment plant exhibited predominant impact by municipal sewage. Fecal indicator loadings were positively associated with antecedent rainfall for three of four stations. No associations were noted between fecal indicator loadings and any of the nutrients. Taxonomic signatures of creek sediment were unique to each sample station, but the sediment microbial community did overlap somewhat following major rain events. No presence of Escherichia coli (E. coli) or enterococci were found in the sediment. At some of the stations it was evident that rainfall was not always the primary driver of fecal transport. Repeated monitoring and analysis of a variety of parameters presented in this study determined that point and non-point sources of fecal pollution varied spatially in association with treated and/or untreated sewage.

WATER RESOURCES OF THE KHOROSTKIV TERRITORIAL COMMUNITY: ECOLOGICAL STATUS, WATER USE PROBLEMS, OPTIMISATION MEASURES

The article analyses the ecological state of surface water resources of the Khorostkiv territorial community (ТС). According to the results of laboratory tests, pathogenic microorganisms, bacteriological indicators exceeding the regulatory requirements, faecal contamination and high content of organic matter were detected in the surface water bodies of the Khorostkiv TC. In addition to the pollution of surface water bodies in the Khorostkiv TC, an important environmental problem worth paying attention to is the lack of sanitary protection and water protection zones for rivers and ponds, as well as the littering of the coastal strip. It was found that the water supply network of the Khorostkiv territorial community includes only the water supply network of the town of Khorostkiv (30 km, unsatisfactory condition), since there are no centralised water supply systems in rural settlements. In the sources of centralised water supply in Khorostkiv, the levels of ammonium nitrogen and colour are exceeded. Hydrochemical analysis of water samples from private wells in Khorostkiv and the villages of Peremyliv and Khlopivka confirmed compliance with the requirements of SanR&amp;R № 400. The volume of daily water consumption and water disposal was analysed. The main sources of pollution of the community's water resources and the volume of wastewater discharges were identified. Priority areas for improving the ecological state of water resources of the Khorostkiv community are substantiated. Keywords: surface water, groundwater, pollutants, water supply, water disposal, territorial community (ТС).

Evaluation Of Some Drinking Water Qualities In Some Villages In Gezira State

Safe and potable water is the basic need for human. In Gezira State groundwater is the main source of domestic water. While most villages in Gezira State traditionally use pit latrines, septic tanks and injection wells have been introduced recently. The aim of this study is to investigate the effect of latrine system in some villages in North Gezira State on some physical, chemical, and microbiological parameters of groundwater. Water samples were collected from sixteen villages (Wadalmahna, Alkamlin Abdalab, Umdagarsey, Wadalmajedi, Abu usher, Altalbab, Alshawarab, Genib, Albataheen, Abufroa, Alsadaga, Alhassaheisa, Alsalama, Addaid Abu usher, Altakla Hamed, and Altakla Gobara) and analyzed for various physico-chemical and microbiological parameters. Physico-chemical parameter includes pH, electrical conductivity, turbidity, total dissolved solids, total hardness, calcium, magnesium, sodium, chloride, and some heavy metals. The microbiologic test includes a total count of coli form and fecal coli form E. coli, which is an indicator of fecal contamination of water. Standard laboratory methods for analysis were used. These parameters were compared with World Health Organization (WHO) and Sudanese Standards and Metrology Organization (SSMO) to assess the suitability of groundwater for domestic purpose. The results show that most of the Physio-chemical parameters are within the acceptable ranges for WHO and SSMO, except water salinity in three villages (Alshawarab, 1935 μmhoscm-1; Albataheen, 1885 μmhoscm-1 and Abufroa, 1780 μmhoscm-1) is higher than the acceptable level (1500 μmhoscm-1). For microbiological tests, total coli form bacteria were detected in all water samples. E. coli was not detected in villages where traditional pit latrine is used. In village where septic tank and injection well is common E. coli was detected in all the samples. The study concludes that the groundwater used for drinking in North Gezira State is polluted, and there is contamination with E. coli in areas where traditional pit latrines are not the sanitation system. Keywords: drinking water, latrine system, Villages in Gezira State, Physical, chemical, groundwater, WHO, microbiological

Significant Factors for Modelling Survival of Escherichia coli in Lake Sediments.

Currently available numerical models that describe the fecal contamination of aquatic environments using Escherichia coli as an indicator bacterium did not consider its survival in sediments. We conducted a series of comparative experiments to reveal the independent and interactive effects of sediment factors, including temperature, pH, water-extractable total dissolved solids (TDSs), coexisting microbes, and sampling sites, in lake environments on E. coli survival. In experiments, E. coli survival was observed by controlling any two factors at a time. Consequently, the decrease in pH and presence of coexisting microbes enhanced E. coli die-off, whereas the addition of water-extractable TDSs promoted its growth. To select factors to be considered for modelling E. coli survival in sediments, the independent effects of each factor and the interaction effect of the two factors were statistically compared based on their effect sizes (η2). As a result, pH (η2 = 59.5-89.0%) affected E. coli survival most significantly, followed by coexisting microbes (1.7-48.4%). Among the interactions affecting E. coli survival, including pH or coexisting microbes-which had larger independent effects-relatively larger statistically significant interactions were observed between pH and coexisting microbes (31.1%), coexisting microbes and water-extractable TDSs (85.4%), and coexisting microbes and temperature (26.4%).

Detection of Salmonella Reservoirs in Birds of Prey Hosted in an Italian Wildlife Centre: Molecular and Antimicrobial Resistance Characterisation.

In the European Union, salmonellosis is one of the most important zoonoses reported. Poultry meat and egg products are the most common food matrices associated with Salmonella presence. Moreover, wild and domestic animals could represent an important reservoir that could favour the direct and indirect transmission of pathogens to humans. Salmonella spp. can infect carnivorous or omnivorous wild birds that regularly ingest food and water exposed to faecal contamination. Birds kept in captivity can act as reservoirs of Salmonella spp. following ingestion of infected prey or feed. In this paper, we describe the isolation of different Salmonella serovars in several species of raptors hosted in aviaries in an Italian wildlife centre and in the raw chicken necks used as their feed but intended for human consumption. Characterisations of strains were carried out by integrating classical methods and whole genome sequencing analysis. The strains of S. bredeney isolated in poultry meat and birds belonged to the same cluster, with some of them being multidrug-resistant (MDR) and carrying the Col(pHAD28) plasmid-borne qnrB19 (fluoro)quinolone resistance gene, thus confirming the source of infection. Differently, the S. infantis found in feed and raptors were all MDR, carried a plasmid of emerging S. infantis (pESI)-like plasmid and belonged to different clusters, possibly suggesting a long-lasting infection or the presence of additional undetected sources. Due to the high risk of fuelling a reservoir of human pathogens, the control and treatment of feed for captive species are crucial.

Assessment of chemical and bacteriological status of treated wastewater of the Baraki WWTP (Algeria) for agricultural purposes

ABSTRACT Due to its geographical location in the arid and semi-arid zone, Algeria is suffering from water stress amplified by the effects of climate change. For these reasons this study was conducted to evaluate the suitability for agricultural reuse of treated wastewater of Baraki WWTP. The quality for agricultural reuse is related to the physicochemical parameters and indicators of water quality. The bacteriological characteristics including total and fecal coliforms, fecal enterococci, Salmonella spp. and Staphylococcus spp. were also considered. The results revealed that SAR and SSP values were excellent for irrigation. A Wilcox diagram showed that most of the samples fell in the field of C3-S1 indicating high salinity and low sodium water. The physicochemical results indicated that most of parameters are in conformity with standards except ammonia NH4+ and total nitrogen that are higher than the permissible limit of USEPA and FAO. The average concentrations of heavy metals are low compared with the FAO recommendations. However, the bacteriological analyses confirmed the existence of germs indicating a fecal contamination exceeding the WHO regulations but an absence of pathogenic germs. Hence, the disinfection of this water and an adequate treatment is needed before its use for agricultural purposes.

Reduced preoperative serum choline esterase levels and fecal peritoneal contamination as potential predictors for the leakage of intestinal sutures after source control in secondary peritonitis

BackgroundThe high rate of stoma placement during emergency laparotomy for secondary peritonitis is a paradigm in need of change in the current fast-track surgical setting. Despite growing evidence for the feasibility of primary bowel reconstruction in a peritonitic environment, little data substantiate a surgeons’ choice between a stoma and an anastomosis. The aim of this retrospective analysis is to identify pre- and intraoperative parameters that predict the leakage risk for enteric sutures placed during source control surgery (SCS) for secondary peritonitis.MethodsBetween January 2014 and December 2020, 497 patients underwent SCS for secondary peritonitis, of whom 187 received a primary reconstruction of the lower gastro-intestinal tract without a diverting stoma. In 47 (25.1%) patients postoperative leakage of the enteric sutures was directly confirmed during revision surgery or by computed tomography. Quantifiable predictors of intestinal suture outcome were detected by multivariate analysis.ResultsLength of intensive care, in-hospital mortality and failure of release to the initial home environment were significantly higher in patients with enteric suture leakage following SCS compared to patients with intact anastomoses (p < 0.0001, p = 0.0026 and p =0.0009, respectively). Reduced serum choline esterase (sCHE) levels and a high extent of peritonitis were identified as independent risk factors for insufficiency of enteric sutures placed during emergency laparotomy.ConclusionsA preoperative sCHE < 4.5 kU/L and generalized fecal peritonitis associate with a significantly higher incidence of enteric suture insufficiency after primary reconstruction of the lower gastro-intestinal tract in a peritonitic abdomen. These parameters may guide surgeons when choosing the optimal surgical procedure in the emergency setting.

Longitudinal Analysis of Urban Stormwater Microbiome and Resistome from Watersheds with and without Green Infrastructure using Long-Read Sequencing

Since stormwater conveys a variety of contaminants into water bodies, green infrastructure (GI) is increasingly being adopted as an on-site treatment solution in addition to controlling peak flows. The purpose of this study was to identify differences in microbial water quality of stormwater in watersheds retrofitted with GI vs. those without GI. Considering stormwater is recently recognized as a contributor to the antibiotic resistance (AR) threat, another goal of this study was to characterize changes in the microbiome and collection of AR genes (resistome) of urban stormwater with season, rainfall characteristics, and fecal contamination. MinION long-read sequencing was used to analyze stormwater microbiome and resistome from watersheds with and without GI in Columbus, Ohio, United States, over 18 months. We characterized fecal contamination in stormwater via culturing Escherichia coli and with molecular microbial source tracking (MST) to identify sources of fecal contamination. Overall, season and storm event (rainfall) characteristics had the strongest relationships with changes in the stormwater microbiome and resistome. We found no significant differences in microbial water quality or the microbiome of stormwater in watersheds with and without GI implemented. However, there were differences between the communities of microorganisms hosting antibiotic resistance genes (ARGs) in stormwater from watersheds with and without GI, indicating the potential sensitivity of AR bacteria to treatment. Stormwater was contaminated with high concentrations of human-associated fecal bacterial genes, and the ARG host bacterial community had considerable similarities to human feces/wastewater. We also identified 15 potential pathogens hosting ARGs in these stormwater resistome, including vancomycin-resistant Enterococcus faecium (VRE) and multidrug-resistant Pseudomonas aeruginosa. In summary, urban stormwater is highly contaminated and has a great potential to spread AR and microbial hazards to nearby environments. This study presents the most comprehensive analysis of stormwater microbiome and resistome to date, which is crucial to understanding the potential microbial risk from this matrix. This information can be used to guide future public health policy, stormwater reuse programs, and urban runoff treatment initiatives.

Level and Origin of Faecal Contamination of the Waters of a Tropical Urban Lagoon: The Case of the Ebrié Lagoon

Level and Origin of Faecal Contamination of the Waters of a Tropical Urban Lagoon: The Case of the Ebrié Lagoon

Seasonal assessment of groundwater quality in the Al Hoceima region, northern Morocco: Physicochemical parameters and fecal contamination indicators

AbstractThis study focuses on assessing the seasonal variation in groundwater quality within the Al‐Hoceima region, specifically examining physicochemical parameters and bacteriological indicators of water fecal contamination. The sampling campaign took place during the wet and dry seasons of 2019 and 2021. In situ measurements were conducted on 37 groundwater samples to determine the physicochemical parameters, while bacteriological analyses were performed using Escherichia coli (E. coli) as a fecal contamination indicator. The findings demonstrate significant variations in physicochemical parameters across seasons and reveal fecal contamination of the groundwater, predominantly indicated by increased levels of E. coli during wet periods. Possible contributing factors include water surface runoff and percolation processes. Additionally, the result showed a high concentration of E. coli expected 240 CFU/100 mL. Pollution was higher in the dry season than in the wet season. These results underscore the poor quality of the water in the Al Hoceima region, necessitating treatment before consumption.

Qualitative detection of E. coli in distributed drinking water using real-time reverse transcription PCR targeting 16S rRNA: Validation and practical experiences

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.

Sources and Prevalence of Cyclospora cayetanensis in Southeastern U.S. Growing Environments

Recent cyclosporiasis outbreaks associated with fresh produce grown in the United States highlight the need to better understand Cyclospora cayetanensis prevalence in U.S. agricultural environments. In this study, C. cayetanensis occurrence was assessed in municipal wastewater sludge, on-farm portable toilets, irrigation pond water, and spent packing house dump tank water in a Southeastern Georgia growing region over two years. Detection of the C. cayetanensis 18S rRNA qPCR gene target in pond samples was 0%, 28%, and 42% (N = 217) depending on the detection definition used, and ≤1% in dump tank samples (N = 46). However, no qPCR detections were confirmed by sequencing, suggesting false detection occurred due to cross-reactions. C. cayetanensis qPCR detections were confirmed in 9% of wastewater sludge samples (N = 76). The human-specific fecal markers HF183 and crAssphage were detected in 33% and 6% of pond samples, respectively, and 4% and 0% of dump tank samples, respectively. Despite community Cyclospora shedding and evidence of human fecal contamination in irrigation water, there was no correlation between C. cayetanensis and HF183 qPCR detections, further supporting that 18S gene target qPCR amplifications were due to cross−reactions. When evaluating C. cayetanensis qPCR environmental detection data, the impact of assay specificity and detection criteria should be considered. Moreover, additional sequence-based testing may be needed to appropriately interpret Cyclospora qPCR environmental data.

Vaginal or Fecal Contamination Which Contributes to Parasite Existence in Urine Sediment

Aims: intended to deepen our knowledge to date regarding parasites that might found in urine sediment as consequences of vaginal or fecal contamination during voiding Discussion: Urine in the bladder is a sterile waste product composed of water soluble nitrogen products. But during voiding, the passage of the urine through lower/outer portion of the urinary tract might come across normal microbiota which function in maintaining the urothelial integrity and preventing urinary tract infection (UTI), as well as promoting local immune function. Parasites and parasitic ova may be seen in urinary sediments as a result of fecal or vaginal contamination. Identification of parasites in centrifuged deposits of urine sediment is a relatively rare occurrence in clinical practice but still must be considered carefully, whether as a consequence of contamination or definite causes of infection. Two of the common parasite found in urine sediment are Trichomonas vaginalis and Enterobius vermicularis. Urine collection procedure must be explained briefly to the patient along with appropriate informed consent prior obtaining the sample. Conclusion: The possibility of parasites being found in urine sediment remain to happen. An in-depth analysis needs to be carried out to determine whether this occurs due to vaginal or rectal contamination or whether it is due to a definitive infection occurring in the urinary tract.

Bacterioplankton diversity in the estuarine regions of two peninsular rivers: A metagenomic approach

ObjectiveIn this present study we evaluated the bacterioplankton diversity employing a culture independent high throughput 16srRNA pyro-sequencing technique in two selected estuarine regions that belongs to two peninsular rivers on which the people living in the area heavily depend for their water needs. In spite of several advantages to metagenome based bacterioplankton diversity analysis, no such studies have been carried out in the region so far. MethodsSamples were collected from three different sites for each estuaries. A comparative study on physico-chemical analysis was done on water samples from the estuaries using standard analytical methods. High-throughput sequencing reads obtained from metagenomic sequencing were classified into a taxonomic category using the NCBI taxonomy reference database. ResultIn the study we observed higher percentage composition of bacterioplanktons appertaining to the actinobacteria, cyanobacteria, and proteobacteria groups which can be attributed to higher levels of water nutrients such as nitrates, nitrites and phosphates. Firmicutes identified in the samples indicates the faecal contamination in the water. Apart from these numerous nitrogen-metabolizing bacteria, such as Roseobacter, Nitratiruptor, and Sulfitobacter, were present, as observed. One of the most common bacterioplankton species that is responsible for the breakdown of different types of organic matter is the Roseobacter. Similarly, nitratiruptor is a type of bacteria that reduces nitrite and can break down nitrate in water. Sulfitobacter and Pseudoruegeria are other two strains observed in both the Chaliyam and Dharmadam estuarine regions. It is reported that the Sulfitobacter strains are predominantly distributed in the areas of oil polluted marine environments;it has been associated with hydrocarbon removal from seawater. ConclusionMost of the diverse bacterioplanktons reported are capable of utilizing the dissolved organic matter for their growth and functioning. Isolation of such bacterial communities is having great significance in the aspects of waste water treatment and pollution abatement. We did not observe any major difference in diversity of particle associated bacterioplanktons in the two estuaries investigated. However, there was a significant variation observed in the diversity of free living bacterioplankton attributed to changes in physio-chemical parameters. Overall, metagenomics is a more effective and insightful way to examine microbial populations than standard culture techniques.

Urban stormwater green infrastructure: Evaluating the public health service role of bioretention using microbial source tracking and bacterial community analyses

Bioretention cells (BRCs) control stormwater flow on-site during precipitation, reducing runoff and improving water quality through chemical, physical, and biological processes. While BRCs are effective in these aspects, they provide habitats for wildlife and may face microbial hazards from fecal shedding, posing a potential threat to human health and the nearby environment. However, limited knowledge exists regarding the ability to control microbial hazards (e.g., beyond using typical indicator bacteria) through stormwater biofiltration. Therefore, the purpose of this study is to characterize changes in the bacterial community of urban stormwater undergoing bioretention treatment, with the goal of assessing the public health implications of these green infrastructure solutions. Samples from BRC inflow and outflow in Columbus, Ohio, were collected post-heavy storms from October 2021 to March 2022. Conventional culture-based E. coli monitoring and microbial source tracking (MST) were conducted to identify major fecal contamination extent and its sources (i.e., human, canine, avian, and ruminant). Droplet digital polymerase chain reaction (ddPCR) was utilized to quantify the level of host-associated fecal contamination in addition to three antibiotic resistant genes (ARGs): tetracycline resistance gene (tetQ), sulfonamide resistance gene (sul1), and Klebsiella pneumoniae carbapenemase resistance gene (blaKPC). Subsequently, 16S rRNA gene sequencing was conducted to characterize bacterial community differences between stormwater BRC inflow and outflow. Untreated urban stormwater reflects anthropogenic contamination, suggesting it as a potential source of contamination to waterbodies and urban environments. When comparing inlet and outlet BRC samples, urban stormwater treated via biofiltration did not increase microbial hazards, and changes in bacterial taxa and alpha diversity were negligible. Beta diversity results reveal a significant shift in bacterial community structure, while simultaneously enhancing the water quality (i.e., reduction of metals, total suspended solids, total nitrogen) of urban stormwater. Significant correlations were found between the bacterial community diversity of urban stormwater with fecal contamination (e.g. dog) and ARG (sul1), rainfall intensity, and water quality (hardness, total phosphorous). The study concludes that bioretention technology can sustainably maintain urban microbial water quality without posing additional public health risks, making it a viable green infrastructure solution for heavy rainfall events exacerbated by climate change.

Detection and comparison of tumor cell-associated microbiota from different compartments of colorectal cancer.

Intratumoral microbes play an important role in the development of colorectal cancer (CRC). However, studying intratumoral microbes in CRC faces technical challenges, as tumor microbe communities are often contaminated by fecal microbes due to the structure of the gut folds and villi. The present study aimed to develop a new method for isolating tumor cell-associated microbiota and comparing microbial populations from different compartments. The distribution of intestinal bacteria was detected using immunohistochemistry combined with 5R-16s rRNA gene sequencing to explore the effects of the sampling site and number of washes on the detection of microbiota. The 5R-16s rRNA gene sequencing was performed using 44 samples from 11 patients with CRC, including CRC tumor tissues (TT), normal tissues adjacent to CRC (NT), tumor cells (TC), and normal cells (NC). TC and NC were obtained from the TT and NT using an enzymatic digestion method. The microbiota and their potential functions in the four groups were analyzed and compared to determine the differential microbiota related to CRC. Bacteria were mainly distributed in the feces covering intestinal tissues and in the epithelial cells and macrophages within the tissues. Different sampling sites and number of washes led to detection of different microbiota distributions. Although the cleaning method could be controlled, sampling sites varied and led to different microbiota distributions. The phyla of Firmicutes and Bacteroidetes were highly abundant in the conventionally used tissue samples, whereas Proteobacteria was the most abundant phyla in the cell samples isolated with the new method (i.e., after cell enzymatic hydrolysis). Detection of CRC cell-associated microbiota using a cell enzymatic digestion method showed that some bacteria, such as Fusobacterium, Eikenella, Shewanella, and Listeria, were more abundant in TT than NT, whereas the abundance of Akkermansia was lower in TT than NT. The tumor/normal ratios of some bacteria, such as Gemella, Escherichia, Shigella, and Blautia, were different between the cell and tissue samples. The cell enzymatic digestion method reduced fecal bacterial contamination, enabling low biomass intratumoral microbiota to be detected and allowing prediction of bacterial distributions.

Capsid Integrity Detection of Enteric Viruses in Reclaimed Waters.

Climate change, unpredictable weather patterns, and droughts are depleting water resources in some parts of the globe, where recycling and reusing wastewater is a strategy for different purposes. To counteract this, the EU regulation for water reuse sets minimum requirements for the use of reclaimed water for agricultural irrigation, including a reduction in human enteric viruses. In the present study, the occurrence of several human enteric viruses, including the human norovirus genogroup I (HuNoV GI), HuNoV GII, and rotavirus (RV), along with viral fecal contamination indicator crAssphage was monitored by using (RT)-qPCR methods on influent wastewater and reclaimed water samples. Moreover, the level of somatic coliphages was also determined as a culturable viral indicator. To assess the potential viral infectivity, an optimization of a capsid integrity PMAxx-RT-qPCR method was performed on sewage samples. Somatic coliphages were present in 60% of the reclaimed water samples, indicating inefficient virus inactivation. Following PMAxx-RT-qPCR optimization, 66% of the samples tested positive for at least one of the analyzed enteric viruses, with concentrations ranging from 2.79 to 7.30 Log10 genome copies (gc)/L. Overall, most of the analyzed reclaimed water samples did not comply with current EU legislation and contained potential infectious viral particles.