Enteric viruses represent a global public health threat and are implicated in numerous foodborne and waterborne disease outbreaks. Nonetheless, relatively little is known of their fate and stability ...in the environment. In this study we used carefully validated methods to monitor enteric viruses, namely adenovirus (AdV), JC polyomavirus (JCV), noroviruses (NoVs), sapovirus (SaV) and hepatitis A and E viruses (HAV and HEV) from wastewater source to beaches and shellfish beds. Wastewater influent and effluent, surface water, sediment and shellfish samples were collected in the Conwy catchment (North Wales, UK) once a month for one year. High concentrations of AdV and JCV were found in the majority of samples, and no seasonal patterns were observed. No HAV and HEV were detected and no related illnesses were reported in the area during the period of sampling. Noroviruses and SaV were also detected at high concentrations in wastewater and surface water, and their presence correlated with local gastroenteritis outbreaks during the spring and autumn seasons. Noroviruses were also found in estuarine sediment and in shellfish harvested for human consumption. As PCR-based methods were used for quantification, viral infectivity and degradation was estimated using a NoV capsid integrity assay. The assay revealed low-levels of viral decay in wastewater effluent compared to influent, and more significant decay in environmental waters and sediment. Results suggest that AdV and JCV may be suitable markers for the assessment of the spatial distribution of wastewater contamination in the environment; and pathogenic viruses can be directly monitored during and after reported outbreaks to prevent further environment-derived illnesses.
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•The TFUF concentration method is suitable for quantifying viruses in water samples.•For the first time, sapovirus was found in UK waters.•Enteric viruses were traceable from source to beaches and shellfish beds.•Norovirus concentrations in the environment agreed with local outbreaks.•PGM assay is useful to study norovirus degradation in the environment.
The recent detection of SARS-CoV-2 RNA in feces has led to speculation that it can be transmitted via the fecal-oral/ocular route. This review aims to critically evaluate the incidence of ...gastrointestinal (GI) symptoms, the quantity and infectivity of SARS-CoV-2 in feces and urine, and whether these pose an infection risk in sanitary settings, sewage networks, wastewater treatment plants, and the wider environment (e.g. rivers, lakes and marine waters). A review of 48 independent studies revealed that severe GI dysfunction is only evident in a small number of COVID-19 cases, with 11 ± 2% exhibiting diarrhea and 12 ± 3% exhibiting vomiting and nausea. In addition to these cases, SARS-CoV-2 RNA can be detected in feces from some asymptomatic, mildly- and pre-symptomatic individuals. Fecal shedding of the virus peaks in the symptomatic period and can persist for several weeks, but with declining abundances in the post-symptomatic phase. SARS-CoV-2 RNA is occasionally detected in urine, but reports in fecal samples are more frequent. The abundance of the virus genetic material in both urine (ca. 102–105 gc/ml) and feces (ca. 102–107 gc/ml) is much lower than in nasopharyngeal fluids (ca. 105–1011 gc/ml). There is strong evidence of multiplication of SARS-CoV-2 in the gut and infectious virus has occasionally been recovered from both urine and stool samples. The level and infectious capability of SARS-CoV-2 in vomit remain unknown. In comparison to enteric viruses transmitted via the fecal-oral route (e.g. norovirus, adenovirus), the likelihood of SARS-CoV-2 being transmitted via feces or urine appears much lower due to the lower relative amounts of virus present in feces/urine. The biggest risk of transmission will occur in clinical and care home settings where secondary handling of people and urine/fecal matter occurs. In addition, while SARS-CoV-2 RNA genetic material can be detected by in wastewater, this signal is greatly reduced by conventional treatment. Our analysis also suggests the likelihood of infection due to contact with sewage-contaminated water (e.g. swimming, surfing, angling) or food (e.g. salads, shellfish) is extremely low or negligible based on very low predicted abundances and limited environmental survival of SARS-CoV-2. These conclusions are corroborated by the fact that tens of million cases of COVID-19 have occurred globally, but exposure to feces or wastewater has never been implicated as a transmission vector.
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•SARS-CoV-2 RNA can be readily detected in feces and occasionally urine.•Severe GI dysfunction only occurs in a small number of cases (11 ± 2%).•Likelihood of SARS-CoV-2 being transmitted via feces appears very low.•Likelihood of infection from sewage-contaminated water or food is extremely low.
Secondary disinfectants, such as chlorine and chloramine, have been widely applied to minimise microbial risks in drinking water during distribution. Key challenges have included the maintenance of ...stable concentrations of disinfectant residuals and the control of disinfection by-products that may form as a consequence of residual decay processes. Many factors may influence disinfectant residual stability and the consequential formation of by-products. Thus predictions of disinfectant stability and by-product formation are multifactorial problems, complete with numerous complications of parameter co-dependence and feedback amplification of some key parameters. The aim of this review was to derive an understanding of how disinfectant residual stability in drinking water distribution systems is impacted by various influencing factors such as water quality and operational parameters. Factors known to influence disinfectant stability and by-product formation were critically reviewed. A systematic review method was applied to identify 1809 journal articles published in the two decades from January 1998 to December 2017. From the initial screening, 161 papers were selected for detailed assessment. Important factors were identified to include temperature, water age, piping material, corrosion products, pH, hydraulic condition, disinfectant residual type and dosage and microbial activity. Microbial activity is a particularly complex parameter on which to base predictions since many factors are known to influence the degree and nature of such activity. These include temperature, water age, piping material, corrosion products, nutrients, natural organic matter, hydraulic condition and disinfectant residual type and dosage. Disinfectant types and dosages were found to be among the most important factors. Many knowledge gaps and research needs still remain, including the need for a more complete understanding of the factors that influence the production of nitrogenous disinfection by-products.
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•Factors intricately affect disinfectant decay and disinfection byproducts formation.•Influencing factors may lead to positive feedback loops on disinfectant stability.•Microbial activity is the most influencing factor among all other factors.•Pipe material is a major factor (in)directly affecting disinfectant stability.•Proposal for predicting disinfectant residual stability by a Bayesian Network model.
Waterborne enteric viruses are an emerging cause of disease outbreaks and represent a major threat to global public health. Enteric viruses may originate from human wastewater and can undergo rapid ...transport through aquatic environments with minimal decay. Surveillance and source apportionment of enteric viruses in environmental waters is therefore essential for accurate risk management. However, individual monitoring of the >100 enteric viral strains that have been identified as aquatic contaminants is unfeasible. Instead, viral indicators are often used for quantitative assessments of wastewater contamination, viral decay and transport in water. An ideal indicator for tracking wastewater contamination should be (i) easy to detect and quantify, (ii) source-specific, (iii) resistant to wastewater treatment processes, and (iv) persistent in the aquatic environment, with similar behaviour to viral pathogens. Here, we conducted a comprehensive review of 127 peer-reviewed publications, to critically evaluate the effectiveness of several viral indicators of wastewater pollution, including common enteric viruses (mastadenoviruses, polyomaviruses, and Aichi viruses), the pepper mild mottle virus (PMMoV), and gut-associated bacteriophages (Type II/III FRNA phages and phages infecting human Bacteroides species, including crAssphage). Our analysis suggests that overall, human mastadenoviruses have the greatest potential to indicate contamination by domestic wastewater due to their easy detection, culturability, and high prevalence in wastewater and in the polluted environment. Aichi virus, crAssphage and PMMoV are also widely detected in wastewater and in the environment, and may be used as molecular markers for human-derived contamination. We conclude that viral indicators are suitable for the long-term monitoring of viral contamination in freshwater and marine environments and that these should be implemented within monitoring programmes to provide a holistic assessment of microbiological water quality and wastewater-based epidemiology, improve current risk management strategies and protect global human health.
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•Human mastadenoviruses are robust indicators for human-associated pollution in water.•Bacteroides-associated phages and crAssphage are promising indicators.•Multiple indicators should be used to assess wastewater treatment efficiency.•Survival and abundance of indicator viruses should be further assessed.
Forest declines caused by climate disturbance, insect pests and microbial pathogens threaten the global landscape, and tree diseases are increasingly attributed to the emergent properties of complex ...ecological interactions between the host, microbiota and insects. To address this hypothesis, we combined reductionist approaches (single and polyspecies bacterial cultures) with emergentist approaches (bacterial inoculations in an oak infection model with the addition of insect larvae) to unravel the gene expression landscape and symptom severity of host–microbiota–insect interactions in the acute oak decline (AOD) pathosystem. AOD is a complex decline disease characterized by predisposing abiotic factors, inner bark lesions driven by a bacterial pathobiome, and larval galleries of the bark-boring beetle
Agrilus biguttatus
. We identified expression of key pathogenicity genes in
Brenneria goodwinii
, the dominant member of the AOD pathobiome, tissue-specific gene expression profiles, cooperation with other bacterial pathobiome members in sugar catabolism, and demonstrated amplification of pathogenic gene expression in the presence of
Agrilus
larvae. This study highlights the emergent properties of complex host–pathobiota–insect interactions that underlie the pathology of diseases that threaten global forest biomes.
Faecal contamination of estuarine and coastal waters can pose a risk to human health, particularly in areas used for shellfish production or recreation. Routine microbiological water quality testing ...highlights areas of faecal indicator bacteria (FIB) contamination within the water column, but fails to consider the abundance of FIB in sediments, which under certain hydrodynamic conditions can become resuspended. Sediments can enhance the survival of FIB in estuarine environments, but the influence of sediment composition on the ecology and abundance of FIB is poorly understood. To determine the relationship between sediment composition (grain size and organic matter) and the abundance of pathogen indicator bacteria (PIB), sediments were collected from four transverse transects of the Conwy estuary, UK. The abundance of culturable Escherichia coli, total coliforms, enterococci, Campylobacter, Salmonella and Vibrio spp. in sediments was determined in relation to sediment grain size, organic matter content, salinity, depth and temperature. Sediments that contained higher proportions of silt and/or clay and associated organic matter content showed significant positive correlations with the abundance of PIB. Furthermore, the abundance of each bacterial group was positively correlated with the presence of all other groups enumerated. Campylobacter spp. were not isolated from estuarine sediments. Comparisons of the number of culturable E. coli, total coliforms and Vibrio spp. in sediments and the water column revealed that their abundance was 281, 433 and 58-fold greater in sediments (colony forming units (CFU)/100g) when compared with the water column (CFU/100ml), respectively. These data provide important insights into sediment compositions that promote the abundance of PIB in estuarine environments, with important implications for the modelling and prediction of public health risk based on sediment resuspension and transport.
Periprosthetic femur fracture (PFF) remains a common reason for failure after total hip arthroplasty (THA). For over 10 years, our institution has performed both anterior approach (AA) and ...posterolateral (PL) approaches for primary THA with multiple stem designs. The aim of this study is to determine the 90-day relative risk of PFF with regard to approach and stem design.
A retrospective review of our institutional database was performed on all patients undergoing primary THA from 2007 to 2018 using AA or PL approaches. Five surgeons performing 6309 THAs (AA = 4510; PL = 1799) using single-wedge taper (n = 2417) or fit-and-fill (n = 3892) stems were included. PFF occurring within 90 days of the index procedure were analyzed. Differences in PFF rates, fracture location, stem type, and treatment method were assessed. Comparisons were made using a Cox regression analysis.
The 90-day revision rate for fracture was 0.3%. Clinically significant fractures requiring cerclage cabling, stem change, revision, or open reduction internal fixation occurred in 0.9% of patients (intraoperative = 37, 0.6%; postoperative = 17, 0.3%). Cox regression found PFF risk was significant for female patients (P = .008), patients older than age 65 (P < .01), single-wedge taper stems (P = .05), and for cases with collarless stems (P = .04). Among PFF cases that required surgical intervention, risk factors were female sex, age older than 65, and body mass index under 25 (P < .05). Collarless stems were 2.6 times more likely to result in PFF than collared stems (P = .04). Single-wedge taper stems were 2.3 times more likely to result in PFF than fit-and-fill stems (P = .05). Approach was not found to be an independent risk factor for PFF (P = .85).
Our single-center experience demonstrates the risk of periprosthetic fracture within 90 days of surgery is significantly lower with collared stems and fit-and-fill stem designs. Female sex, age over 65, and body mass index below 25 nearly double the PFF risk. Surgical approach did not influence fracture rates.
The biological removal of 38 trace organics (pharmaceuticals, endocrine disruptors, personal care products and pesticides) was studied in an anaerobic membrane bioreactor (AnMBR). This work presents ...complete information on the different removal mechanisms involved in the removal of trace organics in this process. In particular, it is focused on advanced characterization of the relative amount of TO accumulated within the fouling layers formed on the membranes. The results show that only 9 out of 38 compounds were removed by more than 90% while 23 compounds were removed by less than 50%. These compounds are therefore removed in an AnMBR biologically and partially adsorbed and retained by flocs and the deposition developed on the membranes, respectively. A total amount of 288 mg of trace organics was retained per m(2) of membrane, which were distributed along the different fouling layers. Among the trace organics analyzed, 17α-ethynylestradiol, estrone, octylphenol and bisphenol A were the most retained by the fouling layers. Among the fouling layers deposited on the membranes, the non-readily detachable layer has been identified as the main barrier for trace organics.
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