Evidence for long-term efficacy of a membrane filtration device in rural villages in Ghana.

Drinking water contaminated by pathogenic micro-organisms increases the risk of infectious gastrointestinal disease which could potentially lead to acute kidney injury and even death, particularly amongst the young and the elderly. Earlier studies have shown a substantial reduction in the incidence of diarrheal disease over a period of one year using a polysulfone membrane water gravity-powered water filtration device. The current report is a continuation of these studies to assess the long-term effects of the innovative method on diarrheal incidence rates over a 4-year follow-up period. This follow-up study monitored the trend of self-reported diarrheal events in all households in the previously studied villages for 5 months, in the last half of each study year, using the same questionnaire utilized in the earlier study. Three villages that had no device yet installed served as controls. We computed monthly diarrheal incidence rates for all study years (standardized to per 100 person-months) and compared these to the pre-device incidence rate in 2018 and in the control group, using the Wilcoxon rank sum exact test. The average diarrheal incidence rates of 1.5 p100pm in 2019, 2.19 p100pm in 2021, and 0.54p100pm in 2022 were significantly different from an earlier study that reported 17.8 p100pm rates before the devices were installed in 2018, (all p-values < 0.05). Concomitantly, self-reported diarrheal infections were substantially higher in the "control villages" not yet having the filtration device installed (80.9, 77.6, and 21.5 per 100 pm). The consistent and large reduction in diarrhea incidence documents the long-term efficacy of the use of the membrane filtration device. This simple water purification method using gravity flow improves public health in remote regions with limited resources.

Assessment of microbial population in integrated CW-MFC system and investigation of organics and fecal coliform removal pathway.

The current study is focused on understanding the operational mechanism of an integrated constructed wetland-microbial fuel cell (CW-MFC) reactor emphasizing fecal coliform (FC) removal. Few studies are available in the literature investigating the inherent mechanisms of pathogen inactivation in a CW-MFC system. Raw domestic wastewater was treated in three vertical reactors, one planted constructed wetland (R1), one planted CW-MFC (R2), and one unplanted CW-MFC (R3). Spatial analysis of treated effluents showed a considerable amount of organics and fecal coliform removal at the vicinity of the anode in R2. Assessment of the microbial population inside all the reactors revealed that EABs (Firmicutes, Bacteroidetes, and Actinobacteria) were more abundant in R2 compared to R1 and R3. During the activity study, biomass obtained from R2 showed a maximum substrate utilization rate of 1.27 mg COD mgVSS-1 d-1. Kinetic batch studies were carried out for FC removal in all the reactors, and the maximum first order FC removal rate was obtained at the anode of R2 as 2.13 d-1 when operated in closed circuit mode. This value was much higher than the natural die-off rate of FCs in raw wastewater which was 1.16 d-1. Simultaneous bioelectricity monitoring inferred that voltage generation can be correlated to faster FC inactivation, which was probably due to EABs outcompeting other exogenous microbes in a preferable anaerobic environment with the presence of an anode. Reactor R2 was found to be functioning as a symbiotic bio-electrochemical mesocosm.

Environmental and Anthropogenic Influences on Coliform Concentrations in the Octopus insularis Production Chain in the Veracruz Reef System, Gulf of Mexico.

Coliforms are relatively common in aquatic environments, but their concentrations can be increased by environmental changes and anthropogenic activities, thus impacting fisheries resources. To determine the microbiological quality in the octopus production chain (capture, post-capture, processing and commercialization), total (TC) and fecal (FC) coliforms were quantified in sea water, fresh octopus, fresh water, ice and octopus in two presentations: packed in ice and boiled. Samples came from fishing zones Enmedio, Chopa and La Gallega at the Veracruz Reef System (VRS) during dry, rainy and windy seasons. The coliforms were determined using the most probable number technique (MPN). The most relevant results indicated that octopus packed in ice coming from the commercialization stage had FC levels >540 MPN/100 g, which exceeded the permissible limits (230 MPN/100 g). Therefore, these products present a risk for human consumption. Differences in FC were observed in octopuses between the three fishing zones (H = 8.697; p = 0.0129) and among the three climatic seasons, increasing during the rainy season, highlighting La Gallega with 203.33 ± 63 MPN (H = 7.200; p = 0.0273). The results provide evidence of the environmental and anthropogenic influences on coliform concentrations and the urgent need to implement an efficient cold chain throughout octopus production stages with adequate handling practices to reverse this situation.

Assessment of multiple fecal contamination sources in surface waters using environmental mitochondrial DNA metabarcoding.

Waterborne diseases are transmitted to humans through the fecal contamination of water, where homeothermic species are the main reservoir. Fecal indicator bacteria (FIB) are often used to determine the occurrence of fecal contamination. However, FIB cannot provide the source of fecal contamination. Furthermore, as fecal inputs and contamination could originate from multiple sources (e.g., human, livestock, wildlife), multiple source tracking markers are required to identify fecal sources. From a previous study, we developed a mitochondrial DNA (mtDNA) metabarcoding approach to assess the presence of multiple homeotherms in four surface waters. Here, we have broadened our approach by sampling 86 surface water samples from the L'Assomption River and Ville-Marie watersheds (Province of Quebec, Canada). Fecal coliform levels were higher than the expected sanitary recommendations for recreational water (> 200 CFU/100 mL) in 73 % samples. The occurrence of mtDNA from human, livestock, domestic animals, wild mammals and wild birds was found in 40-88 % of the samples. Multivariate analyses showed significant covariations between homeothermic taxa and fecal coliforms, enterococci, ß-D-glucuronidase, conductivity, the human-specific Bacteroidales Hf183 genetic marker, and the human population, in the watersheds of L'Assomption River (p = 0.001) and Ville-Marie (p = 0.015) (Province of Quebec, Canada). Through the application of Bayes Theorem, it was determined that fecal coliforms co-occurred with the detection of bovine, beaver, robin and chicken mtDNA in 100 % of cases in the L'Assomption River watershed, and human mtDNA co-occurred with fecal coliforms in 93 % and 76 % of cases in L'Assomption River watershed and Ville-Marie sub-catchment, respectively. This study suggests that fecal contamination could be the result of multiple species, among which some wild animals may contribute to fecal inputs in surface waters, resulting in potential risk to human health. This reinforces the necessity of using the mtDNA metabarcoding method to monitor multi-animal species.

Decaimiento de coliformes fecales en lagunas aireadas de plantas de tratamiento de aguas residuales en Lima metropolitana / Decay of fecal coliforms in aerated lagoons of wastewater treatment plants in metropolitan Lima

A nivel mundial, el 44% de las aguas residuales domésticas no se tratan de forma segura, la recolección y tratamiento de aguas residuales, se ha convertido en un desafío, particularmente en áreas urbanas de bajos ingresos dentro de los países en desarrollo, donde las aguas residuales pueden fluir sin tratar a transportes de aguas pluviales o canales de drenaje informales. No es raro encontrar efluentes, desechos sólidos, excretas humanas y descargas líquidas de industrias y hospitales en las aguas superficiales de muchas zonas urbanas de los países en desarrollo. El proceso de tratamiento de aguas residuales puede ser llevado en lagunas mediante reacciones tanto oxidativas como reductoras. En la capa superior de la laguna, donde las aguas residuales son aeróbicas, ocurre el mecanismo convencional de la demanda bioquímica de oxígeno aeróbico (DBO) y se produce la oxidación del amoníaco. La capa inferior de la laguna es anaerobia, y en esta zona tiene lugar la digestión de los sólidos del lodo, un intermedio, la zona facultativa permite la respiración con aceptores de electrones terminales distintos del oxígeno, esto permite reacciones como la desnitrificación. Los gases producidos en las zonas inferiores se estabilizan en la zona aeróbica por disolución oxígeno, y esto reduce los problemas de olores. Este estudio tiene como objetivo, estudiar el descenso de coliformes fecales en lagunas aireadas de plantas de tratamiento de aguas residuales en la ciudad de Lima, Perú. Los resultados señalan que la separación diferencial de las aguas tratadas, experimentó un descenso del 13 al 26% de coleiformes fecales en todas las lagunas de tratamiento(AU)

Globally, 44% of domestic wastewater is not treated safely, and wastewater collection and treatment has become a challenge, particularly in low-income urban areas within developing countries, where wastewater may flow untreated into stormwater conveyances or informal drainage channels. It is not uncommon to find effluents, solid wastes, human excreta, and liquid discharges from industries and hospitals in the surface waters of many urban areas in developing countries. The wastewater treatment process can be carried out in lagoons through both oxidative and reductive reactions. In the upper layer of the lagoon, where the wastewater is aerobic, the conventional mechanism of aerobic biochemical oxygen demand (BOD) occurs and ammonia oxidation occurs. The lower layer of the lagoon is anaerobic, and in this zone the digestion of the sludge solids takes place, an intermediate, the facultative zone allows respiration with terminal electron acceptors other than oxygen, and this allows reactions such as denitrification. The gases produced in the lower zones are stabilized in the aerobic zone by dissolving oxygen, and this reduces odor problems. The objective of this study is to study the decrease of fecal coliforms in aerated lagoons of wastewater treatment plants in the city of Lima, Peru. The results indicate that the differential separation of the treated waters experienced a decrease from 13 to 26% of fecal coleiforms in all treatment lagoons(AU)

Humans and Hoofed Livestock Are the Main Sources of Fecal Contamination of Rivers Used for Crop Irrigation: A Microbial Source Tracking Approach.

Freshwater bodies receive waste, feces, and fecal microorganisms from agricultural, urban, and natural activities. In this study, the probable sources of fecal contamination were determined. Also, antibiotic resistant bacteria (ARB) were detected in the two main rivers of central Chile. Surface water samples were collected from 12 sampling sites in the Maipo (n = 8) and Maule Rivers (n = 4) every 3 months, from August 2017 until April 2019. To determine the fecal contamination level, fecal coliforms were quantified using the most probable number (MPN) method and the source of fecal contamination was determined by Microbial Source Tracking (MST) using the Cryptosporidium and Giardia genotyping method. Separately, to determine if antimicrobial resistance bacteria (AMB) were present in the rivers, Escherichia coli and environmental bacteria were isolated, and the antibiotic susceptibility profile was determined. Fecal coliform levels in the Maule and Maipo Rivers ranged between 1 and 130 MPN/100-ml, and 2 and 30,000 MPN/100-ml, respectively. Based on the MST results using Cryptosporidium and Giardia host-specific species, human, cattle, birds, and/or dogs hosts were the probable sources of fecal contamination in both rivers, with human and cattle host-specific species being more frequently detected. Conditional tree analysis indicated that coliform levels were significantly associated with the river system (Maipo versus Maule), land use, and season. Fecal coliform levels were significantly (p < 0.006) higher at urban and agricultural sites than at sites immediately downstream of treatment centers, livestock areas, or natural areas. Three out of eight (37.5%) E. coli isolates presented a multidrug-resistance (MDR) phenotype. Similarly, 6.6% (117/1768) and 5.1% (44/863) of environmental isolates, in Maipo and Maule River showed and MDR phenotype. Efforts to reduce fecal discharge into these rivers should thus focus on agriculture and urban land uses as these areas were contributing the most and more frequently to fecal contamination into the rivers, while human and cattle fecal discharges were identified as the most likely source of this fecal contamination by the MST approach. This information can be used to design better mitigation strategies, thereby reducing the burden of waterborne diseases and AMR in Central Chile.

Effect of Pre-Exposure to Chlorine Dioxide on the Susceptibility of Fecal Coliforms to Antibiotics.

Adaptive exposure to sub-lethal concentrations of sanitizers was previously reported to offer cross-protection to bacteria against antibiotics. This study was undertaken to determine whether the pre-exposure of fecal coliforms to suboptimal concentrations of a chemical sanitizer, chlorine dioxide (ClO2), alters their susceptibility to certain antibiotics. Fecal coliforms isolated from fresh fruit packing facilities (n = 12) were adapted in ½ or » of the manufacturer-recommended concentration of ClO2. The susceptibility of the adapted and non-adapted cells to 13 different antibiotics was determined by observing the changes in their minimal inhibitory concentrations (MICs). The results showed that preadaptation to the suboptimal concentrations of ClO2, in general, either decreased or did not change the MICs of the antibiotics against selected fecal coliform isolates, with only two exceptions; preadaptation increased the MICs of kanamycin against two of the fecal coliform isolates, and of nalidixic acid against one of the fecal coliform isolates. The results suggest that the use of ClO2 has a relatively low risk of inducing the resistance of fecal coliforms to antibiotics.

Examining the antimicrobial efficacy of granulated tetraacetylethylenediamine derived peracetic acid and commercial peracetic acid in urban wastewaters.

The ever-increasing need for access to safe water has meant that alternative water sources and innovative water reclamation approaches are often required to meet the global water demand. As a result, many wastewater treatment facilities have faced regulatory pressure to seek alternative disinfection methods that ensure public health safety, while adhering to regulations that set limits on carcinogenic disinfection by-products (DBPs). Peracetic acid (PAA) is an emerging wastewater disinfectant in the United States that has been widely used in other industries such as food sanitization and does not produce carcinogenic DBPs. However, several factors such as transport, storage, and physical and chemical effects have stymied its widespread use in wastewater markets. Therefore, the purpose of this study was to examine the antimicrobial efficacy of an on-site generated PAA compared against a commercially available PAA. Antimicrobial efficacy was assessed using standard fecal contamination indicators (i.e., total coliforms and Escherichia coli) in six urban wastewater treatment facilities ranging in size and treatment processes. Overall, few statistical differences were found between the antimicrobial efficacies of on-site generated PAA and commercially available PAA; however, before becoming more widely utilized, the on-site PAA should be tested against emerging fecal contamination indicators (e.g., human norovirus and enterovirus) and be assessed in terms of economic and sustainability impacts. PRACTITIONER POINTS: Alternative Ct approaches should be considered when using disinfectants like PAA. On-site generated PAA can achieve the same level of disinfection as commercial PAA. On-site generation of PAA may help further its use as a wastewater disinfectant.

Spatial and temporal dynamics and potential pathogenicity of fecal coliforms in coastal shallow groundwater wells.

Access to water through shallow groundwater wells is a common practice in coastal settlements. This, coupled with a lack of planning for wastewater disposal promotes fecal contamination of groundwater and poses a threat to human health. Here, the spatial and temporal dynamics of groundwater fecal contamination was evaluated during summer and winter (2013 and 2014) in a coastal protected area having a high touristic relevance (Cabo Polonio, Uruguay). Fecal coliforms (FC) abundance in groundwater was significantly higher during summer, related to an influx of ~ 1000 tourists per day. A significant spatial autocorrelation was found in 2014, when the abundance of FC in a well was influenced by its three nearest wells (Moran and Geary tests). The applied statistical models (mixed models) indicated that total phosphorus and organic matter were the variables significantly explaining FC abundance. The risk for human health was estimated using groundwater-extracted DNA and qPCR of genes encoding for E. coli virulence factors (stx1, stx2, and eae). Potential Shiga toxin-producing enteropathogenic and enterohemorrhagic pathotypes were detected, even at FC abundances ≤ 1 CFU (100 mL-1). Moreover, we found that contaminated groundwater reached the beach, being the presence of FC in sand detected even in winter and showing its highest frequency nearby groundwater wells consistently having high FC abundance (hot spots). Altogether, the results show that fecal contamination of shallow groundwater in Cabo Polonio involves a risk for human health that intensifies during summer (associated to a significant increase of tourists). This contamination also impacts the beach, where FC can remain through the whole year.

Study of the performance of a cylindrical flow-through electro-Fenton reactor using different arrangements of carbon felt electrodes: effect of key operating parameters.

In this work, a cylindrical flow-through electro-Fenton reactor containing graphite felt electrodes and an Fe(II) loaded resin was evaluated for the production of the Fenton reaction mixture and for the degradation of amoxicillin (AMX) and fecal coliforms containing aqueous solutions. First, the influence of several factors such as treatment time, current intensity, flow rate, and electrode position was investigated for the electrogeneration of H2O2 and the energetic consumption by means of a factorial design methodology using a 24 factorial matrix. Electric current and treatment time were found to be the pivotal parameters influencing the H2O2 production with contributions of 40.2 and 26.9%, respectively. The flow rate had low influence on the responses; however, 500 mL min-1 (with an average residence time of 1.09 min obtained in the residence time distribution analysis) allowed to obtain a better performance due to the high mass transport to and from the electrodes. As expected, polarization was also found to play an important role, since for the cathode-to-anode flow direction, lower H2O2 concentrations were observed when compared with the anode-to-cathode flow arrangement, indicating that part of the H2O2 produced in the cathode was destroyed at the anode. A fluorescence study of hydroxyl radical production, on the other hand, showed that higher yields were obtained using an anode-to-cathode flow direction (up to 3.88 µM), when compared with experiments carried out using a cathode-to-anode flow path (3.11 µM). The removal of a commercial formulation of the antibiotic AMX was evaluated in terms of total organic carbon, achieving up to 57.9% and 38.63% of pollutant mineralization using synthetic and real sanitary wastewater spiked, respectively. Finally, the efficiency of the process on the inactivation of fecal coliforms in sanitary wastewater samples was assessed, reducing 90% of the bacteria after 5 min of electrolysis.

Microbiological Quality and Heavy Metal Concentrations in Slipper Oyster (Crassostrea iredalei) Cultured in Major Growing Areas in Capiz Province, Western Visayas, Philippines: Compliance with International Shellfish Safety and Sanitation Standards.

ABSTRACT: The increasing demand for slipper oyster (Crassostrea iredalei) has propelled farmers to expand oyster cultivation areas in the Philippines, chiefly for local consumption and feasibly for export overseas. As filter feeders, oysters can accumulate pathogens from the surrounding waters, and these pathogens can cause foodborne diseases in consumers. Therefore, oyster farming areas must be monitored for microbiological quality and heavy metal concentrations. In the present study, the microbiological quality of oysters and their growing waters in the major oyster farming areas of the Cogon and Palina Rivers and Cabugao Bay (in Roxas City and the Municipality of Ivisan, respectively, Capiz Province, Western Visayas, Philippines) were examined monthly during the wet (May to October) and dry (November to April) seasons over 12 months. Regardless of the sampling period, high levels of fecal coliforms in the water and Escherichia coli in oysters were found, clearly illustrating that these oyster growing areas would meet only the class B standard under the European Union classification system and would be considered "prohibited" for growing oysters under the U.S. classification system. Although Salmonella was occasionally detected in oysters, Vibrio cholerae was not detected and Vibrio parahaemolyticus was within acceptable limits. The heavy metal concentrations in oyster meat were also determined during the wet (July) and dry (March) seasons. Zinc and copper were the most abundant metals detected, and concentrations of lead, cadmium, mercury, and chromium were below the regulatory limits set by the European Union and the U.S. Food and Drug Administration. These oyster culture areas should be rehabilitated immediately to improve the microbiological quality of the oysters. Oysters harvested from these sites must be depurated or relayed to ensure quality and safety.

Learning hierarchical Bayesian networks to assess the interaction effects of controlling factors on spatiotemporal patterns of fecal pollution in streams.

The dynamics of fecal indicator bacteria, such as fecal coliforms (FC) in streams, are influenced by the interactions of a myriad of factors. To predict complex spatiotemporal patterns of FC in streams and assess the relative importance of numerous controlling factors, the adoption of a hierarchical Bayesian network (HBN) was proposed in this study. By introducing latent variables correlated to the observed variables into a Bayesian network, the HBN can represent causal relationships among a large set of variables with a multilevel hierarchy. The study area encompasses 215 sites across the watersheds of the four major rivers in South Korea. The monitoring data collected during the 2012-2019 period included 32 input variables pertaining to meteorology, geography, soil characteristics, land cover, urbanization index, livestock density, and point sources. As model endpoints, the exceedance probability of the FC standard concentration as well as two pollution characteristics (i.e., pollution degree and type), derived from FC load duration curves were used. The probability of exceeding an FC threshold value (200 CFU/100 mL) showed spatiotemporal variations, whereas pollution degree and type showed spatial variations that represent long-term severity and relative dominance of nonpoint and point source fecal pollution, respectively. The conceptual model was validated using structural equation modeling to develop the HBN. The results demonstrate that the HBN effectively simplified the model structure, while showing strong model performance (AUC = 0.81, accuracy = 0.74). The results of the sensitivity analysis indicate that land cover is the most important factor in predicting the probability of exceedance and pollution degree, whereas the urbanization index explains most of the variability in pollution type. Furthermore, the results of the scenario analysis suggest that the HBN provides an interpretable framework in which the interaction of controlling factors has causal relationships at different levels that can be identified and visualized.

Evaluación de la calidad del agua de la vereda Río Suárez de Puente Nacional, Santander / Water quality evaluation ot the rural area of Río Suárez of Puente Nacional, Santander

Resumen Objetivo. Determinar la calidad del agua que abastece a la población de la Vereda Rio Suarez del municipio de Puente Nacional por medio del cálculo del índice de riesgo de la calidad del agua (IRCA). Métodos. Se tomaron 10 muestras de diferentes puntos de la red de distribución del agua veredal, se realizó análisis físico-químico y microbiológico por técnica de filtración por membrana bajo parámetros del Instituto Nacional de Salud. Resultados. El análisis físico-químico mostró cuantificación de hierro elevado y nivel de turbiedad inadecuado lo que puede afectar el sabor y el aspecto del agua. El recuento de coliformes totales fue >300 UFC/100ml., con identificación de Escherichia coli, Klebsiella oxytoca, Pseudomonas aeruginosa y Enterococcus entre otras, habitantes de suelo y aguas que pueden ser causantes de infecciones gastrointestinales e infecciones urinarias, resultados que indican que el agua no es apta para consumo humano.

Abstract Objective. To determine the quality of the water that supplies the population of the Vereda Rio Suarez of the municipality of Puente Nacional through the calculation of the risk index of water quality (IRCA). Methods. 10 samples were taken from different points of the water distribution network, physical-chemical and microbiological analysis was performed by membrane filtration technique under parameters of the National Institute of Health. Results. The physical-chemical analysis showed high iron quantification and inadequate turbidity level that can affect the taste and appearance of the water. The total coliform count> 300 CFU / 100ml., with identification of Escherichia coli, Klebsiella oxytoca, Pseudomonas aeruginosa and Enterococcus among others that inhabit soils and waters and can cause gastrointestinal infections and urinary infections and is not suitable for human consumption.

Nationwide Assessment of Water Quality in Rivers across Lebanon by Quantifying Fecal Indicators Densities and Profiling Antibiotic Resistance of Escherichia coli.

The use of contaminated water has been associated with severe disease outbreaks. Due to widespread pollution with untreated sewage, concerns have been raised over water quality in Lebanon, a country with well-documented challenges in infrastructure. Here, we evaluated the water quality of major rivers in Lebanon by quantifying the densities of fecal indicator bacteria (fecal coliforms and Escherichia coli). Additionally, we assessed the dissemination of antibiotic-resistant E. coli in river water. Composite water samples (n = 132) were collected from fourteen rivers, and 378 E. coli were isolated and analyzed. Fecal coliforms and E. coli were detected in 96.29% and 95.5% of the samples, respectively. Additionally, 73.48-61.3% and 31.81% of the samples exceeded the microbiological acceptability standards for irrigation and the fecal coliform limit for recreational activities, respectively. The E. coli exhibited resistance to ampicillin (40% of isolates), amoxicillin + clavulanic acid (42%), cefepime (4%), cefotaxime (14%), cefalexin (46%), cefixime (17%), doripenem (0.3%), imipenem (0.5%), gentamicin (6%), kanamycin (9%), streptomycin (35%), tetracycline (35%), ciprofloxacin (10%), norfloxacin (7%), trimethoprim-sulfamethoxazole (32%), and chloramphenicol (13%). Notably, 45.8% of the isolates were classified as multidrug resistant (MDR). Our results highlight the need to urgently address fecal pollution and the dissemination of antibiotic resistance in Lebanese rivers.

Prevalence of Escherichia coli and Antibiotic-Resistant Bacteria During Fresh Produce Production (Romaine Lettuce) Using Municipal Wastewater Effluents.

High demand for food and water encourages the exploration of new water reuse programs, including treated municipal wastewater usage. However, these sources could contain high contaminant levels posing risks to public health. The objective of this study was to grow and irrigate a leafy green (romaine lettuce) with treated wastewater from a municipal wastewater treatment plant to track Escherichia coli and antibiotic-resistant microorganisms through cultivation and post-harvest storage to assess their fate and prevalence. Contamination levels found in the foliage, leachate, and soil were directly (p < 0.05) related to E. coli concentrations in the irrigation water. Wastewater concentrations from 177 to 423 CFU ml-1 resulted in 15-25% retention in the foliage. Leachate and soil presented means of 231 and 116% retention, respectively. E. coli accumulation on the foliage was observed (p < 0.05) and increased by over 400% during 14-day storage (4°C). From randomly selected E. coli colonies, in all four biomass types, 81 and 34% showed resistance to ampicillin and cephalothin, respectively. Reclaimed wastewater usage for leafy greens cultivation could pose potential health risks, especially considering the bacteria found have a high probability of being antibiotic resistance. Successful reuse of wastewater in agriculture will depend on appropriate mitigation and management strategies to guarantee an inexpensive, efficient, and safe water supply.

Effect of Replacing in-Feed Antibiotic Growth Promoters with a Combination of Egg Immunoglobulins and Phytomolecules on the Performance, Serum Immunity, and Intestinal Health of Weaned Pigs Challenged with Escherichia coli K88.

The study was conducted to investigate the effects of replacing antibiotic growth promoters (AGPs) with an egg immunoglobulin (IgY) combined with phytomolecules (PM) on the growth rate, serum immunity, and intestinal health of weaned pigs challenged with Escherichia coli K88 (E. coli K88). A total of 192 piglets were weaned at 28 days old with an average weight of 7.29 (± 0.04) kg. They were randomly divided into four treatments containing eight replicates with six piglets per replicate. The treatment groups were NC and PC fed a basal diet, AGP fed a basal diet supplemented with 75 mg/kg chlortetracycline, 50 mg/kg oxytetracycline calcium, and 40 mg/kg zinc bacitracin, IPM fed a basal diet supplemented with IgY at dose of 2.5 g/kg and 1.0 g/kg and PM at dose of 300 mg/kg and 150 mg/kg during days 1 to 17 and 18 to 42, respectively. On days 7 to 9 of the experiment, piglets in the PC, AGP, and IPM groups were orally challenged with 20 mL E. coli K88 (109 CFU/mL), while piglets in the NC group were challenged with 20 mL medium without E. coli K88. The E. coli K88 challenge model was successful as the incidence of post-weaning diarrhea (PWD) of piglets challenged with E. coli K88 was significantly higher than that of those unchallenged piglets during the challenge time (days 7 to 9) and days 1 to 7 of post-challenge (p < 0.05). A diet with combinations of IgY and PM and AGPs significantly decreased the incidence of PWD during the challenge time and days 1 to 7 of post-challenge (p < 0.05) compared to the PC group and significantly improved the ratio of feed to weight gain (F:G) during days 1 to 17 of the experiment compared to the NC and PC groups (p < 0.05). In comparison with the PC group, piglets in the IPM group had significantly higher serum levels of IgA, IgG, and IgM (p < 0.05), but lower serum IL-1ß on day 17 of experiement (p < 0.05). Besides, diet supplementation with AGP significantly decreased serum IL-1ß, IL-6, and TNF-α on days 17 and 42 (p < 0.05) with comparison to the PC group. Piglets in the IPM group showed a significantly lower level of fecal coliforms (p < 0.05), but a higher villus height of jejunum and ileum and higher ratio of villus height to crypt depth of duodenum and jejunum (p < 0.05) than those piglets in the PC group. In summary, diet supplementation with a mixture of IgY and PM decreased the incidence of PWD and coliforms, increased feed conversion ratio, and improved intestinal histology and immune function.

Using multi-threshold regression techniques to assess river fecal pollution in the highly urbanized Tamsui River watershed.

Rivers are an important urban water resource. This study adopted multivariate linear regression (MLR) and logistic regression (LR) with multiple thresholds to assess river fecal pollution in the Tamsui River watershed using auxiliary environmental data. First, environmental data between 2015 and 2017 on land use, antecedent precipitation, population density, sewerage infrastructure, and river water quality were obtained using geographic information systems and served as explanatory variables. River fecal coliforms (FC), the dependent variable, were also collected for the same period. Then, MLR was used to establish an overall prediction model after validation, and to determine significant factors influencing the level of river fecal pollution. Finally, after stratifying the fecal pollution as low, medium, and high levels, LR with multiple thresholds was employed to explore key factors affecting different FC pollution levels. The study results revealed that land use type and river water quality (other than FC) strongly affected river FC pollution. The discharge of household sewage and wastewater from urban areas was a major source of river FC pollution, particularly for low and medium pollution levels, while farmland land use was negatively correlated with the medium and high levels of river FC pollution in the highly urbanized watershed. Biochemical oxygen demand and suspended solids were highly correlated with medium and high pollution levels in river water.

The relationship between environmental parameters and microbial water quality at two Costa Rican beaches from 2002 to 2017.

Environmental conditions influence fecal indicator bacteria (FIB) levels, which are routinely used to characterize recreational water quality. This study examined 15 years of environmental and FIB data at Puntarenas and Jacó beach, Costa Rica. FIB relationships with sea level, wave height, precipitation, direct normal irradiance (DNI), wind, and turbidity were analyzed. Pearson's correlations identified lags between 24 and 96 h among environmental parameters and FIB. Multiple linear regression models composed of environmental parameters explained 24% and 27% of fecal coliforms and enterococci variability in Jacó, respectively. Puntarenas's models explained 17-26% of fecal coliforms and 12-18% enterococci variability. Precipitation, sea level anomalies, and wave height most frequently explained FIB variability. Hypothesis testing often identified significant differences in precipitation, wave height, daily sea level anomalies, and maximum sea level 24 h prior between days with and without FIB threshold exceedance. Unexpected FIB interactions with DNI, sea level, and turbidity highlight the importance of future investigations.

First detection of Shiga toxin producing Escherichia coli O157:H7 (HlyA gene) and enumeration of most probable number (MPN) of fecal coliforms and Escherichia coli in cage cultured oysters (Crassostrea iredalei) and water from southern Malaysia

Aims@#Escherichia coli O157:H7 is known to be transmitted via fecal-oral route, where water plays a role in the transmission process. Oysters as bivalves, bio accumulate pathogens from the water through filter feeding and are suspected to play a role as disease transmission vector. In Malaysia, the data on oyster’s microbiological quality are limited. Hence, it was vital to conduct oyster related studies in Malaysia. The main objectives of this study include the enumeration of most probable number (MPN) of fecal coliforms and E. coli and isolation of E. coli from oyster (Crassostrea iredalei) and water sample for the detection of 16S rRNA and HlyA (Hemolysin A) genes of E. coli O157:H7. @*Methodology and results@#A total of 120 oysters and water samples (n=6) were collected from a fisherman village located in southern Malaysia. Total fecal coliforms and E. coli were determined using the MPN procedure. Colonies of E. coli were identified based on Gram staining, biochemical test, and PCR detection for the presence of 16S rRNA and HlyA gene of E. coli O157:H7. The enumeration results showed that the MPN of the fecal coliforms and E. coli found in the collected oyster samples do not meet the standard to be directed for human consumption (0.72 ± 0.19 × 104 MPN/100 g and 0.13 ± 0.03 × 10 4 MPN/100 g, respectively). The PCR assays showed that 16 out of the 104 (15.38%) of E. coli isolated from water and oysters showed the presence of HlyA gene. The phylogenetic tree analysis showed there were genetic relationships between the HlyA gene of the E. coli isolated in this study with the ones isolated from calf and human faeces.@*Conclusion, significance and impact of study@#The detection of Shiga toxin producing E. coli O157:H7 (HlyA gene) in cage cultured oysters (C. iredalei) and water from southern Malaysia was first time reported here. In the future, more study can be conducted to study the expression of the HlyA gene and confirm of its identity as E. coli O157:H7 using different target genes such as eaeA (encodes a 94 kD outer membrane protein called intimin) and Stx1 (Shiga toxin, Shigella dysenteriae type 1).

Prevalence and Loads of Fecal Pollution Indicators and the Antibiotic Resistance Phenotypes of Escherichia coli in Raw Minced Beef in Lebanon.

Meat is an important source of high biological value proteins as well as many vitamins and minerals. In Lebanon, beef meats, including raw minced beef, are among the most consumed of the meat products. However, minced beef meat can also be an important source of foodborne illnesses. This is of a major concern, because food safety in Lebanon suffers from well-documented challenges. Consequently, the prevalence and loads of fecal coliforms and Escherichia coli were quantified to assess the microbiological acceptability of minced beef meat in Lebanon. Additionally, antibiotic resistance phenotypes of the E. coli were determined in response to concerns about the emergence of resistance in food matrices in Lebanon. A total of 50 meat samples and 120 E. coli isolates were analyzed. Results showed that 98% and 76% of meat samples harbored fecal coliforms and E. coli above the microbial acceptance level, respectively. All E. coli were resistant to at least one antibiotic, while 35% of the isolates were multidrug-resistant (MDR). The results suggest that Lebanon needs to (1) update food safety systems to track and reduce the levels of potential contamination in important foods and (2) implement programs to control the proliferation of antimicrobial resistance in food systems.