Fecal Bacterial Contamination Research Articles

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.

Fecal bacterial contamination and physicochemical parameters variation near shellfish zones and a hotspot point in Bou-Ismail Bay (Algeria)

Fecal bacterial contamination and physicochemical parameters variation near shellfish zones and a hotspot point in Bou-Ismail Bay (Algeria)

Evolution of the bacterial contamination rates of egg internal contents during its conservation: First report in Algeria

This study was performed to assess the potential for exposure to some potential pathogens in table eggs from 34-week-old ISA Brown laying hens in Algeria. The study was concerned a total of 504 eggs randomly collected during two distinct periods, at two different buildings of laying hens in Algiers. The bacteriological analysis of the different germs for the eggs collected in winter period did not reveal any bacterial contamination for all eggs stored at room temperature and refrigerated. In summer period, no bacteria were found in eggs kept at refrigeration temperature. Therefore, for total germs, the peak of contamination was observed for D14 eggs (3.09 Log CFU/g). No Fecal coliforms bacterial contamination was observed at D0 and D7. A peak fecal streptococci contamination was observed for eggs aged 21 days (2.88 Log CFU /g), and similar values were also observed between D7, D14, D30, these being of the order of 2.49, 2.48 and 2.47 Log CFU /g respectively. Only for 30-day-old eggs, Coagulase positive Staphylococci was registered with a minimal contamination of about 1 Log CFU/g.  These results provide useful indications of the sanitary level of the hens and the state of hygiene on the farm. However, it is necessary to extend the research to other bacteria.

Occurrence of Helicobacter spp. and Fecal Bacterial Contamination in High-altitude Aquatic Environments from the Andes.

The occurrence of Helicobacter spp. and fecal bacterial contamination was investigated in high-altitude environments from the Northeastern Andes of Venezuela. Helicobacter DNA was detected by PCR in streams, drinking and irrigation waters, and one culture from drinking water by the HP enrichment medium for selection of Helicobacter pylori, which displayed 98.98% homology to this pathogen based on 16S rRNA gene sequencing. FISH demonstrated predominant coccoid cells of the target bacteria indicative of the viable but nonculturable (VBNC) state in all water samples and HP cultures. Our work reveals for the first time Helicobacter spp. in waters from one of the highest places in the world. These results, together with the presence of fecal coliforms (2-160 MPN/100mL) from the headwaters of rivers to drinking and irrigation waters, alert fecal contamination and epidemiological implications in this area of ecological and economic importance for the region.

Investigation of bacterial pollution in Ceyhan River (Turkey) and the resistance levels of gram (+) and gram (-) bacteria to antibiotics

In this study, bacteriological pollution of Ceyhan River flowing into Iskenderun Bay (Northeast Mediterranean) and antibiotic resistance of Gram (+) and Gram (-) bacteria were investigated. Water samples were collected from May 2014 to April 2015 in monthly periods and 222 Gram (-) and 74 Gram (+) bacteria were isolated from collected water samples. The isolates were contained 8 different species (Acinetobacter baumannii, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis) which have been identified with Vitek II automated culture system. Microorganism susceptibility tests were performed in accordance with CLSI (Clinical and Laboratory Standards Institute, 2015) criteria. Resistance of the isolates to 15 different antibiotics (Amikacin, Meropenem, Levofloxacin, Imipenem, Piperacillin, Gentamycin, Cefepime, Ceftazidime Penicillin, Oxacillin, Clindamycin, Erythromycin, Ciprofloxacin, Vancomycin, Rifampin) was investigated. The highest antibiotic resistance was found in E. faecalis with 37% against Penicillin antibiotics. No resistance to vancomycin antibiotics has been observed. It was concluded that the Ceyhan River was exposed to fecal bacterial contamination, and it was revealed that this situation would adversely affect both the ecosystem and human health. Measures to protect and improve the ecological and microbiological qualities of rivers and lakes are key to preserving the quality and quantity of water resources for the future.

Faecal bacterial contamination of rivers: Evolution, suitability, and health risk implications for recreational use

AbstractThe suitability of rivers for recreational purposes is an important issue in public health and water management. A quantitative microbial risk assessment was conducted using a dataset of E. coli concentrations in three Sinaloa rivers from 2013 to 2018 to define the level of faecal contamination and estimate the risks of acquiring gastrointestinal infections (GI) from recreational exposure. Faecal contamination was conditioned by river flow or time (p > 0.05) and increase during summer in urban areas. The national laws classify these rivers as suitable for recreational activities. However, the dose‐response model estimated the probability of acquiring GI during recreational use (>1.0 × 10–4), which implies the occurrence of 283 and 788 GI annually in adults and children, respectively. This research exposes the risk for the development of GI in the population of the region, especially in children; and justifies the controlling microbiological quality of rivers used for recreational use.

Permeabilization-free β-galactosidase-induction-based electrochemical detection of Escherichia coli

Abstract Escherichia coli (E. coli) is recognized as an indicator of fecal bacterial contamination, and the induction of intracellular β-galactosidase (Gal) is commonly used for sensitive and selective E. coli detection. However, this method requires a permeabilization process to ensure that the Gal substrate and product are highly permeable through the E. coli membrane, making it unsuitable for simple point-of-care detection. Here, we report a sensitive electrochemical method for E. coli detection that does not require a permeabilization process. Intracellular Gal expression is increased via induction by isopropyl-β- d -thiogalactopyranoside (IPTG). 4-Methoxyphenyl-β- d -galactopyranoside (MPGP) and 4-methoxyphenol (MP) are used as the highly cell-permeable Gal substrate and product, respectively. Externally-added tyrosinase (Tyr) converts MP into electrochemically active 4-methoxycatechol, which is then electrochemically oxidized via electrochemical-chemical redox cycling involving an electrode, 4-methoxycatechol, and tris(2-carboxyethyl)phosphine. The presence of MPGP during the induction of intracellular Gal led to amplified MP production. The results of four different detection methods using three Gal substrates (MPGP, phenyl-β- d -galactopyranoside, and 4-aminophenyl-β- d -galactopyranoside) were compared. The detection limit for both drinking water and tap water spiked with E. coli, obtained following a 2-h-long IPTG treatment and 5-min-long Tyr reaction, was ∼2 × 103 colony-forming units (CFU)/mL, indicating that this method can be applied to monitoring E. coli contamination in water samples. Importantly, the present method does not require the electrode modification, affinity binding, washing, and filtration steps.

The efficiency of a low-cost hydrogen sulphide (H2S) kit as an early warning test for assessing microbial rainwater quality and its correlation with standard indicators microorganisms

AbstractTesting microbial quality of the harvested rainwater remains a challenge in many countries. The H2S test kit is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. This study compares its efficiency with the standard indicators microorganisms in the detection of faecal contamination of rainwater in South Africa. A total of 88 rainwater samples were collected from various tanks in the Eastern Cape, South Africa over three months in 2016. The collected samples were analysed for faecal bacterial contamination using the H2S test kit, Colilert-18/Quanti-tray®/2000 and the membrane filtration technique for faecal coliforms (MFT). The correspondence rate of the H2S test kit with MFT was 88 %, while for the Colilert®it was 76 %. The H2S test kit confirmed faecal contamination when concentrations of standards indicators microorganisms were 5 most-probable number of cells/100 cm3or higher. Overall, the best correspondence of the H2S test kit with Colilert®was observed atE. coliconcentrations above 50 most-probable number of cells/100 cm3. Results of the H2S test kit correlated better with MTF, while the medium used has strongly influenced the enumeration of faecal contamination. Results point to strong effect of media used and revealed the need to calibrate the correspondence between the standard indicator microorganisms and the H2S test kit under local conditions for specific settings.

Bacterial quality of groundwater downgradient of onsite wastewater disposal systems and the influence on eastern Long Island's embayments.

Onsite wastewater disposal systems (OWDS) can introduce bacterial and chemical contaminants, via groundwater, into aquifers and adjacent waterways. We evaluated the concentration of fecal indicator bacteria (FIB) and antibiotic resistant bacteria (ARB) in the shallow groundwater of Eastern Long Island, New York, downgradient of OWDS using cultivation approaches and analysis of 16 S rRNA genes. While FIB and ARB were detected in 80% and 67% of groundwater samples, respectively, concentrations were low, suggesting that, at least at the time of sampling, groundwater was not a large-scale source of fecal bacterial contamination to adjacent embayments. ARB isolates did not include common fecal associated genera and the concentration of FIB and ARB did not correlate well with the concentration of pharmaceutical contaminants, suggesting that bacterial contaminants were poorly linked to OWDS discharge. Concentrations of FIB in the studied embayments were significantly greater in nearshore compared to mid-channel environments, suggesting that land-based sources are likely to be the major contributors of bacterial contamination.

Dispersal of potentially pathogenic bacteria by plastic debris in Guanabara Bay, RJ, Brazil

Analyses of thermotolerant coliform and heterotrophic bacteria as well as Escherichia coli and Vibrio species were carried out on plastic samples and in the surrounding waters of Guanabara Bay to evaluate plastic debris as vehicles of bacterial dispersal. Chemical characterizations of plastics were performed using Fourier transform infrared spectroscopy (FTIR). Plastic debris with high coliform contents were found, while their respective water samples had only low titers. No correlations were observed, however, between the amounts of bacteria and the chemical compositions of the plastic debris. Forty-four bacterial strains were PCR-confirmed as E. coli pathotypes, and 59 strains of Vibrio spp. (with 12 being identified as Vibrio cholerae [6], Vibrio vulnificus [5], and Vibrio mimicus [1]). These findings suggest these plastics can function as a substrate for bacterial biofilms (including pathogens). These debris, in turn, can be dispersed in aquatic environments not otherwise showing recent fecal bacterial contamination.

Foreshore beach sand as a reservoir and source of total phosphorus in Lake Ontario

Many regions around the Great Lakes have been designated Areas of Concern as a result of consistent water quality problems from pollutants like phosphorus and Escherichia coli, which cause eutrophication, beach postings and Beneficial Use Impairments. While foreshore beach sand is a potential reservoir for E. coli, there is less understanding of whether it might also be a reservoir and source of phosphorus for adjacent beach waters. We measured levels of E. coli, total phosphorus and soluble reactive phosphorus at Sunnyside and Rouge Beaches in the Toronto and Region Area of Concern, and stormwater outfalls in the adjacent Humber and Rouge Rivers within their beachsheds. Additionally, we used microbial source tracking assays to detect human and gull fecal contamination. Soluble reactive phosphorus concentrations were highest in stormwater outfalls, with concentrations as high as 556 µg l−1 at an outfall in the Sunnyside beachshed, and 4780 µg l−1 at an outfall in the Rouge beachshed. In contrast, the highest total phosphorus concentrations were typically found in foreshore beach sand pore water and were more associated with gull fecal contamination. Beach sand total phosphorus levels were as high as 10,600 µg l−1 at Sunnyside Beach, although the highest total phosphorus concentration measured (25,600 µg l−1) was in a Rouge River outfall. Concentrations of total phosphorus in outfalls were significantly correlated with concentrations of E. coli in both beachsheds and the human microbial source tracking marker in the Sunnyside beachshed outfalls. These results indicate that stormwater outfalls with sewage cross-contamination can deliver high concentrations of total phosphorus, soluble reactive phosphorus and fecal bacterial contamination to associated beachsheds. Further, similar to E. coli, foreshore beach sand can act as a reservoir of total phosphorus and a source for adjacent water bodies via wave action or groundwater discharge. High phosphorus inputs from beach sand could contribute localized changes to microbial communities and unique eutrophication effects along beach shorelines.

Chemical and biological assessment of sediments and water of Khalid Khor, Sharjah, United Arab Emirates

Water and sediments were collected on March 2013 and April 2014 from Khalid Khor creek area in United Arab Emirates to assess their quality parameters. The pH and alkalinity of the water samples were measured and their values were similar to those of shallow saltwater ecosystems. In addition, elemental analyses and organic compounds were done using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) and Gas Chromatography—Mass Spectroscopy (GC–MS), respectively. The concentration of heavy and trace metals in the water samples were within the acceptable limits except for lead which showed high values, while the concentrations of metals in the sediment samples were relatively high and ranged from 6517 to 13,768mg/kg. GC–MS analysis showed the presence of polyaromatic heterocyclic (PAHs) compounds in sediments near the shipping area and in amounts classified as highly carcinogenic; however, no polychlorinated biphenyls (PCB) were identified. Moreover, fecal bacterial contamination in water was detected in concentrations that range between 300 and 10,140 organisms/100mL.

Bacteriological Quality of Tilapia Fish from Treated Wastewater in Peri-Urban Areas, Morogoro, Tanzania

The aim of this study was to assess faecal bacterial contamination in tilapia fish from wastewater treatment ponds at Mzumbe and in pristine water in Mindu dam. Tilapia fish (fish flesh and fish intestines) and water samples were analysed for Escherichia coli and total plate count. The concentration of E. coli in fish intestines ranged from about 1 - 3.5 log cfu/g and <1 log cfu/g in fish flesh. Total plate count ranged from 1 – 3 log cfu/g in fish flesh and 2 – 6 log cfu/g in fish intestines. The concentration of E. coli in pristine water in Mindu dam ranged from 0 to 15 cfu/mL. From the inlet to outlet of Mzumbe wastewater treatment pond, there was a significant reduction (p<0.05) of E. coli concentration along the gradient from 2.05 to 0.55 log cfu/mL, respectively. These findings demonstrated that tilapia fish from the two study sites were of good quality for human consumption based on microbial faecal contamination. On the other hand treated wastewater of the quality found in this study may be used for aquaculture. However, continuous monitoring for bacteriological quality and safety parameters including E. coli and total plate count is required.

A survey on bacterial contamination of lavage water in electric warm-water lavage toilet seats and of the gluteal cleft after lavage.

Electric warm-water lavage toilet seats are in wide use as an appliance beneficial for the maintenance of hygiene and the prophylaxis and improvement of conditions such as constipation and hemorrhoids. In this study, we surveyed the bacterial content in the lavage water of warm-water lavage toilet seats, and fecal bacterial contamination of the gluteal and genital regions due to droplet infection from post-defecation lavage, to examine the problems inherent to the use of such lavage units. The presence of viable bacteria in lavage water was confirmed in this survey. Viable bacterial counts in lavage water were 3-times higher in household units compared to units in public facilities, suggesting a correlation with the replenishment of lavage tank water with fresh water containing residual free chlorine.

Hydrologic transport of fecal bacteria attenuated by flue gas desulfurization gypsum.

Flue gas desulfurization (FGD) gypsum is a byproduct of coal-fired power plants. Its application to agricultural fields may increase water infiltration, reduce soil erosion, and decrease nutrient losses from applications of animal manures. It may also reduce fecal bacterial contamination of surface waters. We tested the hypothesis that FGD gypsum applications would decrease the load of and the fecal indicator bacterium from poultry litter applications. Two rainfall simulation experiments were undertaken: one in spring 2009 and one in spring 2011. Six treatments consisted of four rates of FGD gypsum (0, 2.2, 4.5, and 9.0 Mg ha) with poultry litter (13.5 Mg ha and two controls) in a randomized, complete-block design with three replications. Each replicate 4- × 6-m plot contained a single 1- × 2-m subplot that was delineated by metal plates and a flume that captured total overland flow or runoff. Rainfall was applied at ∼64 mm h. Volume of overland runoff was measured and subsampled for analysis every 10 min for 1 h. Flow-weighted concentrations, total loads, and soil concentrations of were determined. was not detected in runoff. No significant differences between treatments were observed for the 2009 rainfall simulation. However, after 3 yr of FGD gypsum applications, the highest rate of FGD gypsum resulted in decreased flow-weighted concentrations and total loads of . Flue gas desulfurization gypsum applications may be a management practice that reduces microbial contamination of surface waters from manure applied to agricultural fields in the southeastern United States.

Fecal Indicator Bacteria Contamination of Fomites and Household Demand for Surface Disinfection Products: A Case Study from Peru

Surface-mediated disease transmission is understudied in developing countries, particularly in light of the evidence that surface concentrations of fecal bacteria typically exceed concentrations in developed countries by 10- to 100-fold. In this study, we examined fecal indicator bacterial contamination of dinner plates at 21 households in four peri-urban communities in the Peruvian Amazon. We also used surveys to estimate household use of and demand for surface disinfectants at 280 households. Despite detecting total coliform, enterococci, and Escherichia coli on 86%, 43%, and 24% of plates sampled, respectively, less than one-third of households were regularly using bleach to disinfect surfaces. Among non-users of bleach, only 3.2% of respondents reported a new demand for bleach, defined as a high likelihood of using bleach within the next year. This study highlights the potential for marketing approaches to increase use of and demand for surface disinfectants to improve domestic hygiene.

Assessing and monitoring agroenvironmental determinants of recreational freshwater quality using remote sensing

Diverse fecal and nonfecal bacterial contamination and nutrient sources (e.g. agriculture, human activities and wildlife) represent a considerable non-point source load entering natural recreational waters which may adversely affect water quality. Monitoring of natural recreational water microbial quality is most often based mainly on testing a set of microbiological indicators. The cost and labour involved in testing numerous water samples may be significant when a large number of sites must be monitored repetitively over time. In addition to water testing, ongoing monitoring of key environmental factors known to influence microbial contamination may be carried out as an additional component. Monitoring of environmental factors can now be performed using remote sensing technology which represents an increasingly recognized source of rigorous and recurrent data, especially when monitoring over a large or difficult to access territory is needed. To determine whether this technology could be useful in the context of recreational water monitoring, we evaluated a set of agroenvironmental determinants associated with fecal contamination of recreational waters through a multivariable logistic regression model built with data extracted from satellite imagery. We found that variables describing the proportions of land with agricultural and impervious surfaces, as derived from remote sensing observations, were statistically associated (odds ratio, OR = 11 and 5.2, respectively) with a higher level of fecal coliforms in lake waters in the southwestern region of Quebec, Canada. From a technical perspective, remote sensing may provide important added-value in the monitoring of microbial risk from recreational waters and further applications of this technology should be investigated to support public health risk assessments and environmental monitoring programs relating to water quality.

Fecal bacterial contamination in natural water reservoirs as an indicator of seasonal infection by Opisthorchis viverrini in snail intermediate hosts

Opisthorchis viverrini, a carcinogenic liver fluke, requires Bithynia snails as the first intermediate host, which release cercariae after ingesting fluke eggs from contaminated water. Fecal bacterial contamination and O. viverrini-infected Bithynia snails were investigated in samples collected from natural water reservoirs in Ban Phai, Chonnabot and Muang Districts (Ban Lerngpeuy) in Khon Kaen Province, northeast Thailand, where there is a high incidence of cholangiocarcinoma. Water was sampled and examined six times (February, April, June, August, October and December 2006). The most probable number (MPN) index and coliform counts were utilized to evaluate fecal contamination; the cercarial shedding method was conducted for detecting infected snails. The data revealed that all water samples had a high MPN index number, and fecal coliform levels above the WHO standard. This indicated that water in these reservoirs was contaminated with feces or manure constituents. Water sampling from Ban Lerngpeuy showed full-scale bacterial contamination (> 1609 MPN index) throughout the year. This finding was correlated with the highest prevalence of O. viverrini-infected snails, which were found nearly all year round in this area. Slightly lower fecal contamination levels were detected in water samples from Chonnabot and Ban Phai, with high MPN index numbers and coliform counts from April to October. This corresponded with the higher recovery of infected snails in June and August, but with relatively lower prevalence than those found in Ban Lerngpeuy. Among the sampling sites, the people in Ban Lerngpeuy live nearer to the reservoir than do those in Ban Phai and Chonnabot. These results indicate that fecal bacterial contamination in natural water reservoirs is an important indicator of seasonal transmission of O. viverrini eggs to snail intermediate hosts. Sanitation improvement is essential and future investigations on the sources of contamination are needed.

Molecular approaches for the assessment of fecal bacterial contamination in marine harbor sediments

Molecular approaches for the assessment of fecal bacterial contamination in marine harbor sediments

Seasonal variation in groundwater levels and quality under intensively drained and grazed pastures in the Montagu catchment, NW Tasmania

Water quality is a significant environmental issue in the Montagu River and its estuary in north-west Tasmania. Groundwater is the major contributor to baseflow for about half of the year. ‘Hump and hollow’ surface drainage is increasingly being used to reduce the effects of seasonal waterlogging on pasture production. However, little is known about the effects of ‘hump and hollow’ structures on watertable levels or intensive grazing on groundwater quality in the catchment. The objectives of this study were to evaluate the impacts of ‘hump and hollow’ drainage by comparing watertable levels in drained and undrained paddocks and to quantify the effects of intensive grazing on groundwater quality underlying pastures. In December 2004, 10 wells and 2 piezometers were installed at depths of 2–6 m at seven sites along two transects across the dairying area of Togari. Water levels were monitored and water samples collected every 2 months were analysed for pH, electrical conductivity, total dissolved solids, ammonium, nitrate, nitrite, total nitrogen, dissolved reactive phosphorous, Ca, Mg, K and Na. Thermotolerant coliforms and Enterococcus were measured when watertable levels were low and high. Watertable levels were within 0.5 m of ground level for over 3 months on undrained sites. ‘Hump and hollow’ surface drainage increased the depth of the unsaturated zone under the ‘humps’ but did not lower the watertable. Watertable levels on the crests of the ‘hump and hollow’ structures rose and fell daily in response to periods of rainfall and drought. Gradients of the groundwater surface, albeit very low, indicated the potential for groundwater flow from the base of the hills to the Montagu River in the centre of the valley. The median nitrate concentration of all samples was 0.018 mg NO 3-N L −1 but one site had nitrate concentrations in excess of that recommended for potable water for a period of 1–2 months. Nitrate concentrations varied seasonally by 20–1000 times with an early winter pulse of nitrate evident both in the groundwater and in the Montagu River. In contrast, the median ammonium concentration in the groundwater was 0.274 mg NH 4-N L −1 which was well above the trigger value for lowland streams. The median concentration of dissolved reactive phosphorus was 0.008 mg P L −1 which was slightly higher than the trigger value. There was some evidence of low levels of faecal bacterial contamination of the shallow aquifers. Transects across the dairying area did not clearly demonstrate increasing concentrations of analytes due to intensive grazing though lower levels of nutrients were generally found at sites adjacent to undisturbed native forest. Variation in water quality parameters along the transects suggested water quality at a site was mostly related to local conditions and hazards.