High Faecal Contamination Research Articles

The impact of land use and land cover change on the stream water quality in Limbe I municipality, Cameroon

AbstractInland aquatic ecosystems cover 0.1%–3.0% of Earth's surface. They provide different ecosystem services to the area, such as drinking water, transportation, and hydropower generation. However, increasing land use changes threaten their ecological integrity. This study aims to assess land use and land cover change and their impact on stream water quality in Limbe I municipality. The study was conducted in the rainy season, with sampling points chosen based on anthropogenic impacts. Hanna multi‐probe model number HI9829 was used for in‐situ measurements. The research detects and presents changes in the vegetation cover between three LULC maps (1990, 2010, and 2021). The result suggested that over the last 31 years, vegetation cover decreased by 8.1, 4.8, and 10.6 hectares, respectively. The settlement expanded by 23.5 hectares in the years 1990–2021. In situ measurements, temperature ranged from 23 to 25.8°C; pH, 8–9.4; DO, 1.0–5.9 mg/L; turbidity, 12.4–449.5 NTU; phosphorus, 1–3.4 mg/L. Iron ranges from 0.39 to 0.49 mg/L; cadmium from 0.025 to 0.03 mg/L; and lead from 0.07 to 0.15 mg/L. The heavy metal levels exceed the World Health Organization's acceptable limits for recreational water. The study indicated that the water quality was poor for swimming and aesthetic uses. Total bacteria count ranges from 8500 to 41,000 cfu/mL; total coliforms, 720–6400 cfu/mL;Escherichia coli, 65–300 cfu/mL; and salmonella, 1–46 cfu/mL. The water's bacteriological load indicates high fecal contamination and exceeds the World Health Organization's drinking water limit. LUCC has affected the physico‐chemical and bacteriological quality of the stream water. Hence, the stream needs continuous monitoring of the physico‐chemical and biological indicators to safeguard the aquatic ecosystem's environment and public health.

Unveiling the Dynamics of Cryptosporidium in Urban Surface Water: A Quantitative Microbial Risk Assessment and Insights into Climatic and Seasonal Influences

In response to global urbanization and economic development, urban surface water pollution has become a universal challenge and particularly affects densely populated megacities, and Dhaka is no exception. The discharge of 98% of untreated domestic sewage and massive volumes of industrial wastewater from over 7000 industries escalate surface water crises. This study investigates microbial and fecal contamination with particular emphasis on Cryptosporidium in surface water, known for causing waterborne diseases, such as cryptosporidiosis. Findings reveal high Cryptosporidium oocyst concentrations and fecal contamination in various water bodies in Dhaka City. Among the investigated water bodies, the Buriganga River exhibits the highest Cryptosporidium oocyst concentration (46%), while the Balu River, Turag River, Shitalakkhya River, Dhanmondi Lake, Gulshan Lake, Banani Lake, Ramna Lake, and Crescent Lake also present high levels of oocyst concentrations ranging from 21–40%. This study also calculated infection risks and found that the infection risk of swimming is highest during the wet season and is (3.9 ± 2.2 (95% CI: 3.0–5.0)) × 10−2 per swimming event, whereas it is approximately (2.4 ± 1.9 (95% CI: 1.6–3.3)) × 10−2 during the dry season. Annual diving risks are approximately (1.2 ± 0.6 (95% CI: 0.9–1.4)) × 10−2, indicating considerably high risks. Most of the sampling sites generally show significantly higher risks than other study areas like the Mymensingh and Kushtia Districts. In light of these results, we strongly recommend immediate measures to address water quality issues and mitigate the risks associated with Cryptosporidium contamination in Dhaka’s surface water.

Nanopore sequencing for identification and characterization of antimicrobial-resistant Escherichia coli and Salmonella spp. from tilapia and shrimp sold at wet markets in Dhaka, Bangladesh.

Wet markets in low-and middle-income countries are often reported to have inadequate sanitation resulting in fecal contamination of sold produce. Consumption of contaminated wet market-sourced foods has been linked to individual illness and disease outbreaks. This pilot study, conducted in two major wet markets in Dhaka city, Bangladesh during a 4-month period in 2021 aimed to assess the occurrence and characteristics of Escherichia coli and non-typhoidal Salmonella spp. (NTS) from tilapia (Oreochromis niloticus) and shrimp (Penaeus monodon). Fifty-four individuals of each species were collected. The identity of the bacterial isolates was confirmed by PCR and their susceptibility toward 15 antimicrobials was tested by disk diffusion. The whole genome of 15 E. coli and nine Salmonella spp. were sequenced using Oxford Nanopore Technology. E. coli was present in 60-74% of tilapia muscle tissue and 41-44% of shrimp muscle tissue. Salmonella spp. was found in skin (29%) and gills (26%) of tilapia, and occasionally in muscle and intestinal samples of shrimp. The E. coli had several Multilocus sequence typing and serotypes and limited antimicrobial resistance (AMR) determinants, such as point mutations on glpT and pmrB. One E. coli (BD17) from tilapia carried resistance genes for beta-lactams, quinolones, and tetracycline. All the E. coli belonged to commensal phylogroups B1 and A and showed no Shiga-toxin and other virulence genes, confirming their commensal non-pathogenic status. Among the Salmonella isolates, five belonged to Kentucky serovar and had similar AMR genes and phenotypic resistance patterns. Three strains of this serovar were ST198, often associated with human disease, carried the same resistance genes, and were genetically related to strains from the region. The two undetermined sequence types of S. Kentucky were distantly related and positioned in a separate phylogenetic clade. Two Brunei serovar isolates, one Augustenborg isolate, and one Hartford isolate showed different resistance profiles. This study revealed high fecal contamination levels in tilapia and shrimp sold at two main wet markets in Dhaka. Together with the occurrence of Salmonella spp., including S. Kentucky ST198, a well-known human pathogen, these results stress the need to improve hygienic practices and sanitation standards at markets to improve food safety and protect consumer health.

Metagenomic analysis of microbial communities and antibiotic resistant genes in the Tijuana river, and potential sources

The Tijuana River is a transborder river that flows northwest across the border from Baja California in Mexico into Southern California before discharging into the Pacific Ocean. The river is frequently contaminated with raw sewage due to inadequate sanitary infrastructure in Tijuana. To assess the type and degree of microbial contamination, water samples were collected monthly from a near-border and an estuarine site from August 2020 until May 2021. A portion of each sample was used for epifluorescent microscopy and DNA was extracted directly from the rest for shotgun metagenomic sequencing. After sequence quality checking and processing, we used the rapid taxonomic identifier tool Kaiju to characterize the microbial diversity of the metagenomes and matched the sequences against the Comprehensive Antibiotic Resistance Database (CARD) to examine antimicrobial resistance genes (ARGs). Bacterial and viral-like particle (VLP) abundance was consistently higher in the near-border samples than in the estuarine samples, while alpha diversity (within sample biodiversity) was higher in estuarine samples. Beta-diversity analysis found clear compositional separation between samples from the two sites, and the near-border samples were more dissimilar to one another than were the estuarine sites. Near-border samples were dominated by fecal-associated bacteria and bacteria associated with sewage sludge, while estuarine sites were dominated by marine bacteria. ARGs were more abundant at the near-border site, but were also readily detectable in the estuarine samples, and the most abundant ARGs had multi-resistance to beta-lactam antibiotics. SourceTracker analysis identified human feces and sewage sludge to be the largest contributors to the near-border samples, while marine waters dominated estuarine samples except for two sewage overflow dates with high fecal contamination. Overall, our research determined human sewage microbes to be common in the Tijuana River, and the prevalence of ARGs confirms the importance of planned infrastructure treatment upgrades for environmental health.

Bivalve Shellfish Safety in Portugal: Variability of Faecal Levels, Metal Contaminants and Marine Biotoxins during the Last Decade (2011-2020).

Bivalves are a high-value product whose production has markedly increased, reaching 9863 tonnes in Portugal in 2021. Bivalves' habitats-lagoons, estuaries and coastal waters-are exposed to biological and anthropogenic contaminants, which can bioaccumulate in these organisms and pose a significant public health risk. The need to obtain a safe product for human consumption led to the implementation of standardised hygiene regulations for harvesting and marketing bivalve molluscs, resulting in routine monitoring of bivalve production areas for microbial quality, metal contaminants, and marine biotoxins. While excessive levels of biotoxins and metal contamination lead to temporary harvesting bans, high faecal contamination leads to area reclassification and impose post-harvest treatments. In this study, the seasonal and temporal variability of these parameters were analysed using historical data generated by the monitoring programme during the last decade. Moreover, the impact of the monitoring program on bivalve harvesting from 2011 to 2020 was assessed. This program presented a considerable improvement over time, with an increase in the sampling effort and the overall program representativeness. Finally, contamination risk, revising control measures, and defining recommendations for risk mitigation measures are given in the light of ten years' monitoring.

SARS-CoV-2 contamination potential in environmental and wastewaters in the Algarve region, Southern Portugal

The Ria Formosa, Southern Portugal (Algarve) is a mesotidal lagoon with restricted exchange with Atlantic Ocean. Due to arid Mediterranean climate and absence of large freshwater inputs, the lagoon remains hypersaline relative to adjacent ocean (≥37 psu). Generally, fecal coliforms and land-derived bacteria do not survive long in seawater due to UV, osmotic shock, oligotrophy and competition with marine bacteria. However, survival of human pathogenic viruses in natural waters remains relatively unknown. In view of 2020–2021 SARS-CoV-2 pandemic, this preliminary study aimed to estimate potential contamination by wastewater and persistence in marine environment. Five sampling campaigns (45 total samples) were completed in 2020 and 2021 at three stations in the lagoon, as well as inflow and outflow from three wastewater treatment plants (WWTPs). Despite relatively high fecal contamination at lagoon stations, SARS-CoV-2 could not be detected in surface waters using improved methodology. Untreated wastewaters were positive at Faro-Aeroporto 21/10/2020, 14/12/2020, 08/03/2021; Vilamoura 21/10/2020, 14/12/2020; Olhão 14/12/2020. All treated wastewaters were negative, as well as environmental samples. Highest viral titers were observed in Faro-Aeroporto WWTP on 8 March 2021 (1.35 x 105 genomic copies L−1) coinciding with peak SARS-CoV-2 cumulative positive cases in Algarve (2.03 x 104), yet SARS-CoV-2 was not detected in Vilamoura and Olhão raw wastewater then. Thus, the contamination potential of SARS-CoV-2 seemed non-existent in the Ria Formosa during peak pandemic surges in Algarve. However, predicted climate change and its impact on microbial populations remains a challenge to be addressed by both health and tourist authorities.

Fecal Sampling of Soil, Food, Hand, and Surface Samples from Households in Urban Slums of Dhaka, Bangladesh: An Evidence-Based Development of Baby Water, Sanitation, and Hygiene Interventions.

The aim of this study was to identify the exposure pathways of fecal pathogens for a pediatric population living in the urban slums of Bangladesh. A total of 252 soil, food, surface, and hand rinse samples were collected from the pilot households with children less than 5 years of age. All samples were analyzed using the IDEXX Quanti-Tray System (Colilert-18) to enumerate fecal indicator bacteria Escherichia coli. Escherichia coli was detected in all soil samples collected from children play spaces (N = 46), 35% of objects and surfaces children frequently put in their mouths, and 31% of child food samples. Thirty-three percent of hand samples from the child and 46% of hand samples from the caregiver had detectable E. coli. These findings showed high fecal contamination of soil, food, and on hands and surfaces in households with young children and demonstrate the need for interventions reducing these exposure pathways for susceptible pediatric populations.

Assessment of Water Quality of Kulik River of Raiganj with Reference to Physicochemical Characteristics and Potability

This study involves the assessment of physicochemical and microbiological parameters evaluated from nine sites along the stretch of the Kulik river for one year (during January–December 2020), in and around the town of Raiganj in Uttar Dinajpur district of West Bengal, India. The study was carried out to determine whether the river water can be used for drinking, domestic or household and recreation purposes. The parameters such as water temperature, pH, free carbon dioxide, dissolved oxygen, total alkalinity, total hardness, chlorides and total coliform count were analyzed using standard protocols. Significant differences were observed in the parameters both temporally and spatially. Total coliform count indicated the river water has high faecal contamination. The present study depicts the quality of the river and indicates that the water is non-potable. The result implies that the river needs continuous monitoring and treatment to maintain its aesthetic and hygienic value and to ensure its conservation for the future generation.

A continuous, in-situ, near-time fluorescence sensor coupled with a machine learning model for detection of fecal contamination risk in drinking water: Design, characterization and field validation

We designed and validated a sensitive, continuous, in-situ, remotely reporting tryptophan-like fluorescence sensor and coupled it with a machine learning model to predict high-risk fecal contamination in water (>10 colony forming units (CFU)/100mL E. coli). We characterized the sensor’s response to multiple fluorescence interferents with benchtop analysis. The sensor’s minimum detection limit (MDL) of tryptophan dissolved in deionized water was 0.05 ppb (p <0.01) and its MDL of the correlation to E. coli present in wastewater effluent was 10 CFU/100 mL (p <0.01). Fluorescence response declined exponentially with increased water temperature and a correction factor was calculated. Inner filter effects, which cause signal attenuation at high concentrations, were shown to have negligible impact in an operational context. Biofouling was demonstrated to increase the fluorescence signal by approximately 82% in a certain context, while mineral scaling reduced the sensitivity of the sensor by approximately 5% after 24 hours with a scaling solution containing 8 times the mineral concentration of the Colorado River. A machine learning model was developed, with TLF measurements as the primary feature, to output fecal contamination risk levels established by the World Health Organization. A training and validation data set for the model was built by installing four sensors on Boulder Creek, Colorado for 88 days and enumerating 298 grab samples for E. coli with membrane filtration. The machine learning model incorporated a proxy feature for fouling (time since last cleaning) which improved model performance. A binary classification model was able to predict high risk fecal contamination with 83% accuracy (95% CI: 78% - 87%), sensitivity of 80%, and specificity of 86%. A model distinguishing between all World Health Organization established risk categories performed with an overall accuracy of 64%. Integrating TLF measurements into an ML model allows for anomaly detection and noise reduction, permitting contamination prediction despite biofilm or mineral scaling formation on the sensor’s lenses. Real-time detection of high risk fecal contamination could contribute to a major step forward in terms of microbial water quality monitoring for human health.

Bacteriological quality of community well water and public health concerns in Enugu urban, Nigeria

Background: Water is a basic necessity used by humans for both domestic and industrial uses. Next to air, water is essential to life. It takes up about 71% of the earth’s surface. The objective of this study is to determine the bacteriological quality of well water in Enugu urban, Nigeria&#x0D; Methodology: A total of 60 domestic wells were selected from Abakpa, Obiagu and Achara layouts in Engu urban, Nigeria by stratified random sampling method, with 20 wells selected from each area based on location of well sites and construction parameters. Water samples were collected from each well using a sterile 200ml plastic bottle for bacteriological analysis to estimate total bacteria count in colony forming unit (cfu)/ml, total coliform count in most probable number (mpn)/100ml, and faecal coliform count in most probable number (mpn)/100ml. Bacterial isolates were identified using Gram reaction and conventional biochemical tests including catalase and coagulase for Gram positive bacteria, and oxidase, citrate utilization, hydrogen sulfide, indole, urease, methyl red, Voges Proskauer, and sugar fermentation tests for Gram negative bacteria. Antibiotic susceptibility testing (AST) of each isolate was performed by the disk diffusion method against selected antibiotics including penicillin G (10µg), ciprofloxacin (5µg), streptomycin (10µg), amoxicillin-clavulanic acid (20/10µg), and trimethoprim-sulfamethoxazole (25µg), and result interpreted using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) break points. Comparative statistics of the data was performed using analysis of variance (ANOVA) with p&lt;0.05 considered statistically significant.&#x0D; Results: The well water in the three layouts were heavily contaminated as shown by comparatively high mean total bacteria counts of 0.8825±0.66x104 cfu/ml, 0.8435±0.6413x104 cfu/ml, and 0.8384±0.5948x104 cfu/ml for Abakpa, Obiagu and Achara layouts respectively (p=0.9714). The mean total coliform counts were 5.15±5.284, 5.45±4.31 and 5.05±4.763 mpn/100ml (p=0.8038), and the mean faecal coliform counts were 2.4±3.393, 2.65±2.796 and 2.05±2.35 mpn/100ml (p=0.9631) for Abakpa, Obiagu and Achara layouts respectively. A total of 50 pathogenic bacterial isolates were identified; Klebsiella pneumoniae 21 (43.8%), Escherichia coli 13 (30.0%), Proteus spp 6 (12.5%), Pseudomonas aeruginosa 6 (12.5%), and Staphylococcus aureus 2 (4.2%). The AST result shows that 75% of K. pneumoniae, E. coli, Proteus spp and S. aureus were resistant to all five antibiotics tested.&#x0D; Conclusion: These findings showed high faecal contamination of domestic well water sources, which poses a significant infection risk to the community. Proper water treatment measures and personal hygiene practices are recommended, and well sites should be located at a safe distance from septic tanks, pit latrines, flowing gutters and refuse dump sites.

Evaluation of Water Quality of Buritis Lake

The implementation of natural parks in cities is a current and controversial theme. Therefore, in Lake Buritis, which is a leisure area for the population of the city of Goiatuba, Goiás, Brazil, the quality of the water was analyzed, carrying out quantitative tests of the water samples at six different points between the source and the outlet of the lake that flows into the stream, Chico À Toa. Physical–chemical tests (turbidity, pH, alkalinity, electrical conductivity, color, nitrate and hardness parameters), microbiological tests for species identification, analysis of the antimicrobial susceptibility profile, metals analysis and Allium cepa test, were performed. The total coliforms number in water samples was higher than the maximum value established by Brazilian legislation, demonstrating high fecal contamination during the spring in samples from an artesian well. The bacterial diversity found was large and there were many pathogenic bacteria. The A. cepa test demonstrated a cytotoxic potential for water from the source and outlet of Buritis Lake. Statistical tests were applied to verify existing correlations between parameters. Among the analyzed data, the highest correlation was between the color and turbidity parameters and the grouping between the metals (lead, iron, cadmium and magnesium).

Compost Quality and Sanitation on Industrial Scale Composting of Municipal Solid Waste and Sewage Sludge

Municipal solid waste and sewage sludge are produced in large quantities that are often managed through industrial composting treatment. Because of their origin, composition, and complexity, ensuring adequate stabilization of the organic matter, and sanitation of fecal contaminants during composting is of the utmost significance, and difficult to achieve on an industrial scale. In this study, the operations of six industrial composting facilities that process municipal solid waste and sewage sludge were evaluated from the point of view of the sanitation achieved and the quality of the compost produced. In addition, the results were compared using the model of industrial compost from green waste. Differences between the plants were ascribable to operations other than composting systems. High phytotoxicity and fecal contamination above legislation thresholds were found in compost produced from municipal solid waste. In contrast, compost from sewage sludge were more stable and mature than those produced from green waste, and also had an adequate level of sanitation. The raw material and operational factors are of great relevance to obtain a stable, mature, and pathogen-free compost.

Drinking water, sanitation, and hygiene (WASH) situation in primary schools of Pakistan: the impact of WASH-related interventions and policy on children school performance.

The United Nation's Sustainable Development Goals include the target of ensuring access to water and sanitation and hygiene (WASH) for all; however, very few studies have assessed comprehensive school WASH service in Pakistan. The purpose of this study was to identify WASH services in primary schools of Pakistan, and to assess how recent WASH interventions and policies are associated with the school's academic performance. A representative cross-sectional study was conducted in primary schools in the Sindh province of Pakistan. Structured observations and interviews were done to ascertain the schools' WASH conditions. The primary exposures of interest were the implementation of previous WASH interventions and National WASH policy in the school and the WASH coverage. Outcomes of interest included WASH conditions and school performance. The structural equation modeling (SEM) using a bootstrap resampling procedure was employed to characterize how WASH exposures were associated with WASH conditions and school performance. Data were collected from 425 schools. The Basic WASH facilities coverage in the primary schools of Sindh remains overall low according to WHO WASH service ladder criteria. Also, inconsistency in all three inclusive domains of WASH (availability, accessibility, and functionality) facilities were found. The school performance was significantly associated (P<0.001) with the presence of WASH interventions and/or WASH policy, while WASH policy and/or recent WASH intervention at the school were not associated with overall water quality. Our assessment unveiled several WASH gaps that exist, including high heavy metal and fecal contamination. Adoption of national WASH policy and financing of evidence-based WASH interventions are recommended in primary schools to improve educational outcomes.

High Fecal Contamination and High Levels of Antibiotic-Resistant Enterobacteriaceae in Water Consumed in the City of Maputo, Mozambique.

Simple SummaryThe high number of diarrheal disease cases in developing countries is related to sanitation conditions, consumption of untreated water, and poor individual and collective hygiene. In this study, the microbiological quality of water sold and consumed in the city of Maputo, Mozambique, and the antibiotic resistance profile of Enterobacteriaceae isolated from these samples were evaluated. The results showed the occurrence of microorganisms that indicate fecal contamination with enterococci, fecal coliforms, and Escherichia coli above the limit legally allowed for drinking water. The antibiotic resistance profile revealed the existence of antibiotic-resistant bacteria. These results show the need to improve the water supply system in the city of Maputo and to educate the population on hygiene to reduce health risks and promote well-being. In the city of Maputo, Mozambique, food and water are often sold on the streets. Street water is packaged, distributed, and sold not paying attention to good hygienic practices, and its consumption is often associated with the occurrence of diarrheal diseases. Coincidentally, the increase of diarrheal diseases promotes the inappropriate use of antibiotics that might cause the emergence of antibiotic-resistant bacterial strains. In this context, the present study aimed to assess the microbiological quality of water sold on the streets of Maputo, as well as the antibiotic resistance profile of selected Enterobacteriaceae isolates. The 118 water samples analyzed were from street home-bottled water (n = 81), municipal water distribution systems (tap water) (n = 25), and selected supply wells in several neighborhoods (n = 12). The samples were analyzed for total mesophilic microorganisms, fecal enterococci, fecal coliforms, Escherichia coli, and Vibrio spp. The results showed a high level of fecal contamination in all types of water samples. In home-bottled water, fecal coliforms were found in 88% of the samples, and E. coli in 66% of the samples. In tap water, fecal coliforms were found in 64%, and E. coli in 28% of the samples. In water from supply wells, fecal coliforms and E. coli were found in 83% of the samples. From 33 presumptive Vibrio spp. colonies, only three were identified as V. fluvialis. The remaining isolates belonged to Aeromonas spp. (n = 14) and Klebsiella spp. (n = 16). Of 44 selected Enterobacteriaceae isolates from water samples (28 isolates of E. coli and 16 isolates of Klebsiella spp.), 45.5% were not susceptible to the beta-lactams ampicillin and imipenem, 43.2% to amoxicillin, and 31.8% to amoxicillin/clavulanic acid. Regarding non-beta-lactam antibiotics, there was a high percentage of isolates with tolerance to tetracycline (52.3%) and azithromycin (31.8%). In conclusion, water in Maputo represents a risk for human health due to its high fecal contamination. This situation is made more serious by the fact that a relatively high percentage of isolates with multidrug resistance (40%) were found among Enterobacteriaceae. The dissemination of these results can raise awareness of the urgent need to reduce water contamination in Maputo and other cities in Mozambique.

Spatial arrangement of well and latrine and their influence on water quality in clayey soil – a study in low-income peri-urban neighborhoods in Lichinga, Mozambique

Abstract In this study, the influence of the spatial arrangement of shallow wells and pit latrines on water quality was evaluated in clayey soil during dry and rainy seasons, using 123 randomly selected wells. The distance between well and the nearest latrine was measured and the location of the well in the yard was characterized. The colony forming units (CFU/100 mL) of fecal coliforms were quantified, and pH, electrical conductivity (CE) and turbidity were measured. 100% of the wells were located less than 25 m from the latrine, 74.8% were located in the middle of the yard. In the dry season, 42.4% of the samples presented up to 12 CFU/100 mL, and in the rainy season, 84.4% presented up to 139 CFU/100 mL. 56.9% had pH values between 6.5 and 8.5, and 63.4% presented EC values between 50 and 571 μS/cm. In the dry season, 40.7% of the samples had values below 5 NTU, and 59.3% up to 50 NTU. In the rainy season, 86.6% had values between 6 and 300 NTU. Pearson's correlation between all variables was weak. The wells are susceptible to high fecal contamination, although the clayey soil seems to mitigate the expected high levels of microbial contamination.

A study on the bacteriological characterization of the coastal Tangier seawater: Preliminary results

This paper deals, on the one hand, with a study of bacteriological parameters of coastal water in the region of Tangier Ksar-Sghir, north of Morocco, and secondly, with an examination of the influence of temperature parameter on biological processes occurring within seawater. The bacteriological study concerns E. coli, fecal coliforms (F.C), total coliforms (T.C) and fecal streptococcus (F.S). A campaign of 25 sampling points spread over four layers of concentration was conducted in the coastal line during the year of 2017 and The overall results of tests were obtained using the Principal Component Analysis method. (PCA). The analysis has highlighted differentiated areas in term of sanitary quality. The highest values obtained were in the zone of Tangier-Med port showing high fecal contamination by pollution indicator bacteria (T.C, F.C, E. coli and F.S) with high temperature values that result in short-, medium- and long-term environmental pollution.

Child hand contamination is associated with subsequent pediatric diarrhea in rural Democratic Republic of the Congo (REDUCE Program).

The Reducing Enteropathy, Undernutrition, and Contamination in the Environment (REDUCE) program focuses on identifying exposure pathways to faecal pathogens for young children in the Democratic Republic of the Congo (DRC) and on developing scalable interventions to reduce faecal contamination from these pathways. A prospective cohort study of 690 participants was conducted to investigate the association between hand, food, and environmental faecal contamination and diarrhoeal disease prevalence among young children in Walungu Territory, South Kivu, DRC. A total of 1923 hand rinse, soil, food, object, surface, stored water and water source samples were collected during unannounced spot checks after baseline enrolment and analysed for Escherichia coli. Caregiver reports of diarrhoea were obtained from children<5years at a 6-month follow-up. E.coli was detected in 73% of child and caregiver hand-rinse samples, 69% of soil samples from child play spaces, 54% of child food samples, 38% of objects and surfaces children were observed putting in their mouths, 74% of stored water samples, and 40% of source water samples. Children<5years with E. coli on their hands had significantly higher odds of diarrhoea at the 6-month follow-up (odds ratio: 2.03 (95% confidence interval: 1.05, 3.92)). The cohort study findings from the REDUCE program have shown that child hand contamination is associated with diarrhoeal disease in rural DRC, and that there is high faecal contamination in child plays spaces and food. These findings provide evidence demonstrating the urgent need to provide clean play spaces for young children and interventions targeting hand hygiene to reduce paediatric exposure to faecal pathogens.

Fecal Contamination of Drinking Water Was Associated with Diarrheal Pathogen Carriage among Children Younger than 5 Years in Three Peruvian Rural Communities.

Drinking water contamination is a frequent problem in developing countries and could be associated with bacterial pathogen carriage in feces. We evaluated the association between the risk of drinking water and bacterial carrier status in children younger than 5 years in a cross-sectional study conducted in 199 households from three Peruvian rural communities. Fecal samples from children were screened for pathogenic Aeromonas, Campylobacter, and Vibrio species, as well as for Enterobacteriaceae, including pathogenic Escherichia coli. The drinking water risk was determined using E. coli as an indicator of contamination. Nineteen (9.5%) children were colonized with pathogens and classified as carriers, all without diarrhea symptoms. Of 199 drinking water samples, 38 (19.1%) were classified as very high risk because of high fecal contamination (> 100 E. coli/100 mL). Shared-use water sources, daily washing of containers, and washing using only water were associated with higher prevalence of bacterial carriage, whereas there was no association between households reporting boiling and chlorination of water and carrier status. The prevalence of carriage in children exposed to very high-risk water was 2.82 (95% CI: 1.21-6.59) times the prevalence of those who consumed less contaminated water, adjusted by the water source and daily washing. Our results suggest that household drinking water plays an important role in the generation of carriers with diarrheal pathogens. Our findings also highlight the importance of interventions to ensure the safety of drinking water. Further studies are needed to validate the observed association and determine its significance with respect to diarrhea in the community.

Principal component analysis exploring the association between antibiotic resistance and heavy metal tolerance of plasmid-bearing sewage wastewater bacteria of clinical relevance.

This paper unravels the occurrence of plasmid-mediated antibiotic resistance in association with tolerance to heavy metals among clinically relevant bacteria isolated from sewage wastewater. The bacteria isolated were identified following conventional phenotypic and/or molecular methods, and were subjected to multiple-antibiotic resistance (MAR) profiling. The isolates were tested against the heavy metals Hg2+, Cd2+, Cr2+ and Cu2+. SDS-PAGE and agarose gel electrophoretic analyses were performed, respectively, for the characterization of heavy metal stress protein and R-plasmid among the isolated bacteria. Principal component analysis was applied in determining bacterial resistance to antibiotics and heavy metals. Both lactose-fermenting ( Escherichia coli ) and non-fermenting ( Acinetobacter baumannii and Pseudomonas putida ) Gram-negative bacterial strains were procured, and showed MAR phenotypes with respect to three or more antibiotics, along with resistance to the heavy metals Hg2+, Cd2+, Cr2+ and Cu2+. The Gram-positive bacteria, Enterococcus faecalis , isolated had ‘ampicillin–kanamycin–nalidixic acid’ resistance. The bacterial isolates had MAR indices of 0.3–0.9, indicating their ( E. faecalis , E. coli , A. baumannii and P. putida ) origin from niches with high antibiotic pollution and human faecal contamination. The Gram-negative bacteria isolated contained a single plasmid (≈54 kb) conferring multiple antibiotic resistance, which was linked to heavy metal tolerance; the SDS-PAGE analysis demonstrated the expression of heavy metal stress proteins (≈59 and ≈10 kDa) in wastewater bacteria with a Cd2+ stressor. The study results grant an insight into the co-occurrence of antibiotic resistance and heavy metal tolerance among clinically relevant bacteria in sewage wastewater, prompting an intense health impact over antibiotic usage.

Challenges for contact recreation in a tropical urban lake: assessment by a water quality index

Water pollution control is challenging in catchments affected by ‘informal’ urban development. Lake Pampulha, an impoundment that is a major tourist focus within the municipality of Belo Horizonte, Minas Gerais state, Brazil, provides an example of degradation of aquatic environments by disorganised urbanization. We evaluated the current recreational suitability of the lake using state government monitoring data (2012-2017) with reference to Brazilian legislation and a water quality index for contact recreation in Brazilian freshwaters, considering E. coli (indicating faecal pollution and microbial hazards), cyanobacterial density (health risks and aesthetic quality), turbidity (aesthetics and safety associated with visual clarity), and pH (safety and eye-comfort). Our results show that, despite investments in pollution control, the recreational water quality of Lake Pampulha remains very poor. Contact recreation was most limited by persistent cyanobacterial blooms, but also faecal contamination and low visual water clarity. The effects of high phosphorus loading and faecal contamination from unsewered domestic wastewater is exacerbated by a tropical climate, promoting stable thermal stratification (favouring cyanobacterial dominance) and turbid wet-season runoff. Water quality indexing is a powerful tool not just for interpreting and communicating multiple metrics affecting water resources, but also for guiding rehabilitation efforts and tracking progress.