33 research outputs found

    Carbapenem-resistant bacteria in a secondary wastewater treatment plant

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    Bacterial resistance to carbapenems is an emerging problem of this century. A carbapenem-resistant bacterial population (CRBP) grown at 42°C was monitored in the influent and effluent of a secondary municipal wastewater treatment plant over 10 months. The municipal wastewater consisted of domestic, industrial, hospital and storm wastewaters. Median numbers of CRBP in influent and effluent water were 3.5 and 1.3 log CFU/mL, with its prevalence among total heterotrophic bacteria at 47% and 26%, respectively. Correlation of CRBP with physico-chemical and other bacteriological parameters of wastewater was estimated. Higher numbers of CRBP in influent and effluent were found in cases of nutrient-rich wastewater with higher concentrations of total heterotrophic bacteria and intestinal enterococci. Reduction of CRBP in the wastewater treatment process of 54% was comparable to the reduction of intestinal enterococci. Despite the significant elimination of CRBP in the secondary type of wastewater treatment plant, substantial numbers of CRBP are released through the effluent into the natural receiving waters. Since the CRBP grown at 42°C was not found in natural water samples beyond the vicinity of hospitals, these bacteria may be used as an indicator of hospital wastewaters.Keywords: environmental bacteria, carbapenem-resistant bacteria, public health, wastewate

    Setting a baseline for global urban virome surveillance in sewage

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    The rapid development of megacities, and their growing connectedness across the world is becoming a distinct driver for emerging disease outbreaks. Early detection of unusual disease emergence and spread should therefore include such cities as part of risk-based surveillance. A catch-all metagenomic sequencing approach of urban sewage could potentially provide an unbiased insight into the dynamics of viral pathogens circulating in a community irrespective of access to care, a potential which already has been proven for the surveillance of poliovirus. Here, we present a detailed characterization of sewage viromes from a snapshot of 81 high density urban areas across the globe, including in-depth assessment of potential biases, as a proof of concept for catch-all viral pathogen surveillance. We show the ability to detect a wide range of viruses and geographical and seasonal differences for specific viral groups. Our findings offer a cross-sectional baseline for further research in viral surveillance from urban sewage samples and place previous studies in a global perspective

    Global monitoring of antimicrobial resistance based on metagenomics analyses of urban sewage

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    Antimicrobial resistance (AMR) is a serious threat to global public health, but obtaining representative data on AMR for healthy human populations is difficult. Here, we use meta-genomic analysis of untreated sewage to characterize the bacterial resistome from 79 sites in 60 countries. We find systematic differences in abundance and diversity of AMR genes between Europe/North-America/Oceania and Africa/Asia/South-America. Antimicrobial use data and bacterial taxonomy only explains a minor part of the AMR variation that we observe. We find no evidence for cross-selection between antimicrobial classes, or for effect of air travel between sites. However, AMR gene abundance strongly correlates with socio-economic, health and environmental factors, which we use to predict AMR gene abundances in all countries in the world. Our findings suggest that global AMR gene diversity and abundance vary by region, and that improving sanitation and health could potentially limit the global burden of AMR. We propose metagenomic analysis of sewage as an ethically acceptable and economically feasible approach for continuous global surveillance and prediction of AMR.Peer reviewe

    Author's personal copy Occurrence of sepiolite in Croatia and its application in phosphate removal from wastewater

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    This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit

    Effects of Formic Acid on the Adsorption of Escherichia Coli

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    Adsorption of Escherichia coli K 88 on natural and acid-modified clinoptilolite was studied under ambient conditions. The materials under study were characterized in terms of surface area and cation-exchange capacity (CEC). Our study results indicate that treatment with formic acid can increase the Brunauer–Emmett–Teller (BET) surface area, CEC and adsorption capacity of clinoptilolite. The maximum adsorption on these non-metallic minerals was 25 mg/ml, beyond which the adsorption decreased as the amount of adsorptive increased. Time-dependent studies showed that the adsorption process reached equilibrium after 2 hours. The adsorption on E. coli K 88 increased with increasing concentration of the adsorption agent as well as with increasing concentration of the bacteria in suspension. The desorption of H + was studied by washing with a sterile physiological saline solution for 2 hours. The adsorption–desorption hysteresis suggests that the desorption rate of acid-modified clinoptilolite was much lower than that of natural clinoptilolite (P < 0.05). Acid modification of clinoptilolite increased the amount of bacterial adsorption due to the attractive interactions between the clinoptilolite and the bacteria. This increase may also involve the BET surface area and the surface characteristics of clinoptilolite
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