Antibiotic resistance genes in bacteriophages from wastewater treatment plant and hospital wastewaters. - Related Documents




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331801.0000Antibiotic resistance genes in bacteriophages from wastewater treatment plant and hospital wastewaters. Antibiotic resistant bacteria (ARB) are a major health risk caused particularly by anthropogenic activities. Acquisition of antibiotic resistances by bacteria is known to have happened before the discovery of antibiotics and can occur through different routes. Bacteriophages are thought to have an important contribution to the dissemination of antibiotic resistance genes (ARGs) in the environment. In this study, seven ARGs (bla(TEM), bla(SHV), bla(CTX-M), bla(CMY), mecA, vanA, and mcr-1) were investigated, in the bacteriophage fraction, in raw urban and hospital wastewaters. The genes were quantified in 58 raw wastewater samples collected at five WWTPs (n = 38) and hospitals (n = 20). All genes were detected in the phage DNA fraction, with the bla genes found in higher frequency. On the other hand, mecA and mcr-1 were the least frequently detected genes. Concentrations varied between 10(2) copies/L and 10(6) copies/L. The gene coding for the resistance to colistin (mcr-1), a last-resort antibiotic for the treatment of multidrug-resistant Gram-negative infections, was identified in raw urban and hospital wastewaters with positivity rates of 19 % and 10 %, respectively. ARGs patterns varied between hospital and raw urban wastewaters, and within hospitals and WWTP. This study suggests that phages are reservoirs of ARGs, and that ARGs (with particularly emphasis on resistance to colistin and vancomycin) in the phage fraction are already widely widespread in the environment with potential large implications for public health.202337315610
331910.9999Extended-spectrum beta-lactamase (ESBL)-positive Enterobacteriaceae in municipal sewage and their emission to the environment. The spread of Gram-negative bacteria with plasmid-borne extended-spectrum beta-lactamases (ESBLs) has become a worldwide problem. Their prevalence is increasing, both in hospitals and in the environment. The aim of this study was to investigate the presence of ESBL-positive Enterobacteriaceae in municipal sewage and their emission to the ambient air and the river receiving effluent from wastewater treatment plant (WWTP). In the group of 455 isolated strains, up to 19.8% (90 isolates) were phenotypic ESBL-producers. They were detected in the 63 (100%) of sewage samples analyzed, 7 (33.3%) of river water and in 10 (23.8%) of air samples collected at the WWTP area. The plasmid-mediated genes encoding beta-lactams resistance were detected in almost 10% out of bacteria of the WWTP's final effluents and in above 32% out of bacteria of air at the WWTP area. It confirms that those genes are released into the environment, which might facilitate further dissemination among environmental bacteria. Moreover, genes encoding antibiotic resistance were shown to be transferrable to an Escherichia coli recipient strain, which indicates a high possibility of horizontal gene transfer among strains of different genera within the sewage and environmental samples. This study demonstrated that despite the treatment, the municipal sewage may be a reservoir of antibiotic-resistant microorganisms and plasmid-mediated antibiotic resistance genes. This may pose a public health risk, which requires future evaluation and control.201323886578
331720.9999Prevalence and Diversity of Antibiotic Resistance Genes in Swedish Aquatic Environments Impacted by Household and Hospital Wastewater. Antibiotic-resistant Enterobacteriaceae and non-lactose fermenting Gram-negative bacteria are a major cause of nosocomial infections. Antibiotic misuse has fueled the worldwide spread of resistant bacteria and the genes responsible for antibiotic resistance (ARGs). There is evidence that ARGs are ubiquitous in non-clinical environments, especially those affected by anthropogenic activity. However, the emergence and primary sources of ARGs in the environment of countries with strict regulations for antibiotics usage are not fully explored. The aim of the present study was to evaluate the repertoire of ARGs of culturable Gram-negative bacteria from directionally connected sites from the hospital to the wastewater treatment plant (WWTP), and downstream aquatic environments in central Sweden. The ARGs were detected from genomic DNA isolated from a population of selectively cultured coliform and Gram-negative bacteria using qPCR. The results show that hospital wastewater was a reservoir of several class B β-lactamase genes such as bla (IMP-1) , bla (IMP-2), and bla (OXA-23), however, most of these genes were not observed in downstream locations. Moreover, β-lactamase genes such as bla (OXA-48), bla (CTX-M-8), and bla (SFC-1), bla (V IM-1), and bla (V IM-13) were detected in downstream river water but not in the WWTP. The results indicate that the WWTP and hospital wastewaters were reservoirs of most ARGs and contribute to the diversity of ARGs in associated natural environments. However, this study suggests that other factors may also have minor contributions to the prevalence and diversity of ARGs in natural environments.201931019498
331530.9999Occurrence of the mcr-1 Colistin Resistance Gene and other Clinically Relevant Antibiotic Resistance Genes in Microbial Populations at Different Municipal Wastewater Treatment Plants in Germany. Seven wastewater treatment plants (WWTPs) with different population equivalents and catchment areas were screened for the prevalence of the colistin resistance gene mcr-1 mediating resistance against last resort antibiotic polymyxin E. The abundance of the plasmid-associated mcr-1 gene in total microbial populations during water treatment processes was quantitatively analyzed by qPCR analyses. The presence of the colistin resistance gene was documented for all of the influent wastewater samples of the seven WWTPs. In some cases the mcr-1 resistance gene was also detected in effluent samples of the WWTPs after conventional treatment reaching the aquatic environment. In addition to the occurrence of mcr-1 gene, CTX-M-32, blaTEM, CTX-M, tetM, CMY-2, and ermB genes coding for clinically relevant antibiotic resistances were quantified in higher abundances in all WWTPs effluents. In parallel, the abundances of Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli were quantified via qPCR using specific taxonomic gene markers which were detected in all influent and effluent wastewaters in significant densities. Hence, opportunistic pathogens and clinically relevant antibiotic resistance genes in wastewaters of the analyzed WWTPs bear a risk of dissemination to the aquatic environment. Since many of the antibiotic resistance gene are associated with mobile genetic elements horizontal gene transfer during wastewater treatment can't be excluded.201728744270
331340.9999The Prevalence and Characterization of Extended-Spectrum β-Lactamase- and Carbapenemase-Producing Bacteria from Hospital Sewage, Treated Effluents and Receiving Rivers. Hospital sewage plays a key role in the dissemination of antibiotic-resistant genes (ARGs) by serving as an environmental antimicrobial resistance reservoir. In this study, we aimed to characterize the cephalosporin- and carbapenem-resistant isolates from hospital sewage and receiving rivers. The results showed that ESBL (bla(CTX-M)) and carbapenemase genes (bla(NDM) and bla(KPC)) were widely detected in a number of different bacterial species. These resistance genes were mainly harbored in Enterobacteriaceae, followed by Acinetobacter and Aeromonas isolates. More attention should be given to these bacteria as important vectors of ARGs in the environment. Furthermore, we showed that the multidrug resistance phenotype was highly prevalent, which was found in 85.5% Enterobacteriaceae and 75% Acinetobacter strains. Notably, the presence of carbapenemase genes in isolates from treated effluents and receiving rivers indicates that the discharges of wastewater treatment plants could be an important source for high-risk resistance genes propagation to the environment. In conclusion, this study shows a high prevalence of ESBL- and carbapenemase-producing bacteria in hospital sewage and receiving rivers in China. These findings have serious implications for human health, and also suggest the need for more efforts to control the dissemination of resistant bacteria from hospital sewage into the environment.202032069792
531350.9999Treated wastewater: A hotspot for multidrug- and colistin-resistant Klebsiella pneumoniae. Wastewater treatment plants are hotspots for the release of antimicrobial resistant pathogenic bacteria into aquatic ecosystems, significantly contributing to the cycle of antimicrobial resistance. Special attention should be paid to antimicrobial resistant ESKAPE bacteria, which have been identified as high-priority targets for control measures. Among them, Klebsiella pneumoniae is particularly noteworthy. In this study, we collected wastewater samples from the inlet, sedimentation tank, and effluent water of a wastewater treatment plant in June, July, October, and November of 2018. We detected and characterized 42 K. pneumoniae strains using whole genome sequencing (15 from the inlet, 8 from the sedimentation tank, and 19 from the effluent). Additionally, the strains were tested for their antimicrobial resistance phenotype. Using whole genome sequencing no distinct patterns were observed in terms of their genetic profiles. All strains were resistant to tetracycline, meanwhile 60%, 47%, and 37.5% of strains isolated from the inlet, sedimentation tank, and effluent, respectively, were multidrug resistant. Some of the multidrug resistant isolates were also resistant to colistin, and nearly all tested positive for the eptB and arnT genes, which are associated with polymyxin resistance. Various antimicrobial resistance genes were linked to mobile genetic elements, and they did not correlate with detected virulence groups or defense systems. Overall, our results, although not quantitative, highlight that multidrug resistant K. pneumoniae strains, including those resistant to colistin and genetically unrelated, being discharged into aquatic ecosystems from wastewater treatment plants. This suggests the necessity of monitoring aimed at genetically characterizing these pathogenic bacteria.202439053799
533060.9999Surveillance on ESBL-Escherichia coli and Indicator ARG in Wastewater and Reclaimed Water of Four Regions of Spain: Impact of Different Disinfection Treatments. In the present study, the occurrence of indicator antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) both in the influent and the effluent of four Spanish wastewater treatment plants (WWTPs) was monitored for 12 months, and the susceptibility profiles of 89 recovered extended spectrum β-lactamase (ESBL)-producing Escherichia coli isolates were obtained against a wide range of antimicrobials. The aim of the study was to better understand whether the current wastewater treatment practices allow us to obtain safe reclaimed water mitigating the spread of ARB and ARGs to the environment. Results showed high concentrations of ESBL-producing E. coli as well as a high prevalence of a range of ARGs in the influent samples. The reclamation treatments implemented in the WWTPs were effective in reducing both the occurrence of ESBL E. coli and ARGs, although significant differences were observed among WWTPs. Despite these reductions in occurrence observed upon wastewater treatment, our findings suggest that WWTP effluents may represent an important source of ARGs, which could be transferred among environmental bacteria and disseminate antimicrobial resistance through the food chain. Remarkably, no major differences were observed in the susceptibility profiles of the ESBL E. coli isolated from influent and effluent waters, indicating that water treatments do not give rise to the emergence of new resistance phenotypes.202336830310
331670.9999Winter is coming - Impact of temperature on the variation of beta-lactamase and mcr genes in a wastewater treatment plant. Wastewater treatment plants (WWTP) play a key role in the dissemination of antibiotic resistance and analyzing the abundance of antibiotic resistance genes (ARGs) and resistant bacteria is necessary to evaluate the risk of proliferation caused by WWTPs. Since few studies investigated the seasonal variation of antibiotic resistance, this study aimed to determine the abundance of beta-lactamase and mcr genes and to characterize phenotypic resistant strains in a WWTP in Germany over the seasons. Wastewater, sewage sludge and effluent samples were collected over a one year period and analyzed using quantitative real-time PCR. Resistant strains were isolated, followed by identification and antibiotic susceptibility testing using VITEK 2. The results show a significantly higher occurrence of nearly all investigated ARGs in the wastewater compared to sewage sludge and effluent. ARG abundance and temperature showed a negative correlation in wastewater and significant differences between ARG abundance during warmer and colder seasons were determined, indicating a seasonal effect. Co-occurrence of mcr-1 and carbapenemase genes in a multi-drug resistant Enterobacter cloacae and Escherichia coli producing extended-spectrum beta-lactamase (ESBL) was determined. To the best of our knowledge, this is the first detection of mcr-1, bla(VIM) and bla(OXA-48) in an ESBL-producing E. coli. Although wastewater treatment reduced the abundance of ARGs and resistant strains, a dissemination into the river might be possible because carbapenemase-, CTX-M- and mcr-1-gene harboring strains were still present in the effluent.202031945531
194280.9999Occurrence of antibiotic resistance among Gram negative bacteria isolated from effluents of fish processing plants in and around Mangalore. The presence of antibiotic-resistant bacteria in seafood not only poses a serious health risk for the consumers but also contributes to the spread of these antibiotic-resistant bacteria in the natural environments through the effluents discharged from the fish processing plants. The aims of this study were to isolate Gram-negative bacteria from the effluents of fish processing plants in and around Mangalore, India and to profile their antibiotic resistance pattern. Maximum resistance was seen for ampicillin (40.78%) followed by tetracycline (40.22%) and nitrofurantoin (29.05%). Further, the detection of genes that contribute to antibiotic resistance revealed the presence of sulfonamide resistance genes (sul1 and sul2) and extended spectrum β-lactamase genes (bla (CTX-M), bla (TEM)) in a few isolates. The presence of such bacteria in fish processing effluents is a matter of great concern because they can contribute significantly to the antibiotic resistance in the natural environment. It is imperative that seafood processing plants follow the safe disposal of effluents in order to reduce or eliminate the antibiotic resistance menace.202031112036
330990.9999Prevalence of a carbapenem-resistance gene (KPC), vancomycin-resistance genes (van A/B) and a methicillin-resistance gene (mecA) in hospital and municipal sewage in a southwestern province of Saudi Arabia. OBJECTIVE: According to the World Health Organization, the increasing antibiotic resistance of pathogens is one of the most important threats to human health. Prevalence of a carbapenem-resistance gene (KPC), vancomycin-resistance genes (van A/B) and a methicillin-resistance gene (mecA) in hospital and municipal sewages will be potential threat to public health. RESULTS: Vancomycin-resistance genes were detected in the sewage of community tank-II, sewage tank of the tertiary and general hospital. Carbapenem-resistance gene was detected in sewage of community tank-II and sewage from tertiary hospital. Methicillin-resistance gene was detected in sewage of community tank-II, sewage from a fish market sewage tank and sewage from an animal slaughter house sewage tank. The detection of a KPC, van A/B and a mecA in sewages will help further the process to take the appropriate measures to prevent the spread of such bacteria in the environment.201829335025
2573100.9999Molecular Characterization and Prevalence of Antimicrobial-Resistant Escherichia coli Isolates Derived from Clinical Specimens and Environmental Habitats. Antibiotic-resistant bacteria (ARB) are present in wastewaters as their elimination during treatment in wastewater treatment plants (WWTPs) is often impossible. Water plays an important role in the spread of these microorganisms among humans, animals and the environment. This study aimed to assess the antimicrobial resistance patterns, resistance genes and molecular genotypes by means of phylogenetic groups of E. coli isolates in aquatic habitats, including sewage and receiving water bodies, as well as clinical settings in the Boeotia regional district of Greece. The highest resistance rates among both environmental and clinical isolates were observed to be for penicillins, ampicillin and piperacillin. Resistance patterns related to extended spectrum β-lactamases (ESBL) production and ESBL genes were also detected in both environmental and clinical isolates. Phylogenetic group B2 was predominant in clinical settings and the second most frequent among wastewaters, whereas group A was dominant in all environmental isolates. In conclusion, the studied river water and wastewaters may serve as reservoirs of resistant E. coli isolates that pose potential threats to both human and animal health.202337374900
5314110.9999High prevalence of colistin resistance genes in German municipal wastewater. Bacterial resistance against the last-resort antibiotic colistin is of increasing concern on a global scale. Wastewater is suspected to be one of the pathways by which resistant bacteria and the respective genes are disseminated. We employed a metagenomics approach to detect and quantify colistin resistance genes in raw municipal wastewater sampled at 9 locations all over Germany (14 samples in total, collected in 2016/2017). Our data support the findings of earlier studies according to which the prevalence of the colistin resistance gene mcr-1 is still low. However, we were able to demonstrate that the total prevalence of colistin resistance genes is dramatically underestimated if the focus is put on that specific gene alone. In comparison to mcr-1, other gene variants like mcr-3 and mcr-7 proved to be 10 to 100 times more abundant in samples of untreated wastewater. The average relative abundances expressed as copies per 16S rRNA gene copies were 2.3×10(-3) for mcr-3, 2.2×10(-4) for mcr-4, 3.0×10(-4) for mcr-5, and 4.4×10(-4) for mcr-7. While these four gene variants were ubiquitous in all 14 samples, mcr-1 was detected only once at a relative abundance of 1.4×10(-5). Our results suggest a high risk of increasing incidence of colistin resistance as large amounts of mcr genes are continuously disseminated to diverse microbial communities via the wastewater path.201931398645
3298120.9999Comparison of antibiotic-resistant bacteria and antibiotic resistance genes abundance in hospital and community wastewater: A systematic review. Antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) are constantly shed into the aquatic environment, with hospital wastewater potentially acting as an important source for resistance spread into the environment. A systematic review was conducted aiming to investigate the role of hospital wastewater on dissemination of antimicrobial resistance in the aquatic environment. Studies included in the review compared the prevalence of ARB and/or ARGs in hospital versus community wastewater. Data were extracted on ARB and/or ARG prevalence. Data on sampling techniques, microbiological methodology and risk of bias of included studies were recorded. Thirty-seven studies were included. Higher frequencies of antibiotic resistance determinants were found in hospital wastewater compared to community sources in 30/37 (81%) of included studies. However, trends for specific multi-drug-resistant bacteria differed. Antibiotic-resistant Gram-negative were more prevalent in hospital compared to community wastewaters, with higher concentrations of extended-spectrum-beta-lactamase-producing pathogens and carbapenemase-producing Enterobacteriaceae in hospital sources in 9/9 studies and 6/7 studies, respectively. Hospitals did not contribute consistently to the abundance of vancomycin-resistant Enterococci (VRE); 5/10 studies found higher abundance of VRE in hospital compared to community wastewaters. Reporting on sampling methods, wastewater treatment processes and statistical analysis were at high risk of bias. Extreme heterogeneity in study methods and outcome reporting precluded meta-analysis. Current evidence concurs that hospital wastewater is an important source for antibiotic resistance in aquatic environments, mainly multidrug-resistant Gram-negative bacteria. Future research is needed to assess the effect of wastewater treatment processes on overall antibiotic resistance in the aquatic environment.202032758846
5372130.9999Transfer potentials of antibiotic resistance genes in Escherichia spp. strains from different sources. Multidrug-resistant Escherichia coli and antibiotic-resistance genes (ARGs) present a danger to public health. However, information on the dissemination potentials of antibiotic resistance among bacteria from different environments is lacking. We isolated multiple antibiotic-resistant Escherichia spp. from animal farms, hospitals, and municipal wastewater-treatment plants (MWWTPs) using culture-based methods, and carried out resistance phenotype and gene analyses. Thirty-five isolates of multiple antibiotic-resistant Escherichia spp. were further screened to detect 61 ARGs, 18 mobile genetic elements (MGEs), and gene cassettes. The isolates from livestock manure and MWWTPs showed greater diversity in plasmid profiling than hospital wastewater. Each Escherichia sp. carried 21-26 ARGs and 8-12 MGEs. In addition, 11 gene cassettes were detected in 34 Escherichia isolates, with greater diversity in livestock manure and MWWTPs than in hospital wastewater. The results indicated that the potential for ARG transfer was higher in livestock manure and MWWTPs compared with human clinical sources, possibly related to the high occurrence of both residual antibiotics and heavy metals in these environments.202031896018
2744140.9999Bacteria isolated from hospital, municipal and slaughterhouse wastewaters show characteristic, different resistance profiles. Multidrug-resistant bacteria cause difficult-to-treat infections and pose a risk for modern medicine. Sources of multidrug-resistant bacteria include hospital, municipal and slaughterhouse wastewaters. In this study, bacteria with resistance to 3rd generation cephalosporins were isolated from all three wastewater biotopes, including a maximum care hospital, municipal wastewaters collected separately from a city and small rural towns and the wastewaters of two pig and two poultry slaughterhouses. The resistance profiles of all isolates against clinically relevant antibiotics (including β-lactams like carbapenems, the quinolone ciprofloxacin, colistin, and trimethoprim/sulfamethoxazole) were determined at the same laboratory. The bacteria were classified according to their risk to human health using clinical criteria, with an emphasis on producers of carbapenemases, since carbapenems are prescribed for hospitalized patients with infections with multi-drug resistant bacteria. The results showed that bacteria that pose the highest risk, i. e., bacteria resistant to all β-lactams including carbapenems and ciprofloxacin, were mainly disseminated by hospitals and were present only in low amounts in municipal wastewater. The isolates from hospital wastewater also showed the highest rates of resistance against antibiotics used for treatment of carbapenemase producers and some isolates were susceptible to only one antibiotic substance. In accordance with these results, qPCR of resistance genes showed that 90% of the daily load of carbapenemase genes entering the municipal wastewater treatment plant was supplied by the clinically influenced wastewater, which constituted approximately 6% of the wastewater at this sampling point. Likewise, the signature of the clinical wastewater was still visible in the resistance profiles of the bacteria isolated at the entry into the wastewater treatment plant. Carbapenemase producers were not detected in slaughterhouse wastewater, but strains harboring the colistin resistance gene mcr-1 could be isolated. Resistances against orally available antibiotics like ciprofloxacin and trimethoprim/sulfamethoxazole were widespread in strains from all three wastewaters.202032763594
1941150.9999The association between antimicrobials and the antimicrobial-resistant phenotypes and resistance genes of Escherichia coli isolated from hospital wastewaters and adjacent surface waters in Sri Lanka. The presence of antimicrobials, antimicrobial-resistant bacteria (ARB), and the associated antimicrobial resistance genes (ARGs) in the environment is a global health concern. In this study, the concentrations of 25 antimicrobials, the resistance of Escherichia coli (E. coli) strains in response to the selection pressure imposed by 15 antimicrobials, and enrichment of 20 ARGs in E. coli isolated from hospital wastewaters and surface waters were investigated from 2016 to 2018. In hospital wastewaters, clarithromycin was detected at the highest concentration followed by sulfamethoxazole and sulfapyridine. Approximately 80% of the E. coli isolates were resistant, while 14% of the isolates exhibited intermediate resistance against the tested antimicrobial agents. Approximately 61% of the examined isolates were categorized as multidrug-resistant bacteria. The overall abundance of phenotypes that were resistant toward drugs was in the following order: β-lactams, tetracycline, quinolones, sulfamethoxazole/trimethoprim, aminoglycosides, and chloramphenicol. The data showed that the E. coli isolates frequently harbored bla(TEM), bla(CTX-M), tetA, qnrS, and sul2. These results indicated that personal care products were significantly associated with the presence of several resistant phenotypes and resistance genes, implying their role in co-association with multidrug resistance. Statistical analysis also indicated a disparity specific to the site, treatment, and year in the data describing the prevalence of ARB and ARGs and their release into downstream waters. This study provides novel insights into the abundance of antimicrobial, ARB and ARGs in Sri Lanka, and could further offer invaluable information that can be integrated into global antimicrobial resistance databases.202133894511
3299160.9999Metagenomic analysis of β-lactamase and carbapenemase genes in the wastewater resistome. The emergence and spread of resistance to antibiotics among bacteria is the most serious global threat to public health in recent and coming decades. In this study, we characterized qualitatively and quantitatively β-lactamase and carbapenemase genes in the wastewater resistome of Central Wastewater Treatment Plant in Koziegłowy, Poland. The research concerns determination of the frequency of genes conferring resistance to β-lactam and carbapenem antibiotics in the genomes of culturable bacteria, as well as in the wastewater metagenome at three stages of treatment: raw sewage, aeration tank, and final effluent. In the final effluent we found bacteria with genes that pose the greatest threat to public health, including genes of extended spectrum β-lactamases - bla(CTX-M), carbapenemases - bla(NDM), bla(VIM), bla(GES), bla(OXA-48), and showed that during the wastewater treatment their frequency increased. Moreover, the wastewater treatment process leads to significant increase in the relative abundance of bla(TEM) and bla(GES) genes and tend to increase the relative abundance of bla(CTX-M), bla(SHV) and bla(OXA-48) genes in the effluent metagenome. The biodiversity of bacterial populations increased during the wastewater treatment and there was a correlation between the change in the composition of bacterial populations and the variation of relative abundance of β-lactamase and carbapenemase genes. PCR-based quantitative metagenomic analysis combined with analyses based on culture methods provided significant information on the routes of ARBs and ARGs spread through WWTP. The limited effectiveness of wastewater treatment processes in the elimination of antibiotic-resistant bacteria and resistance genes impose the need to develop an effective strategy and implement additional methods of wastewater disinfection, in order to limit the increase and the spread of antibiotic resistance in the environment.202031756613
1939170.9999Detection of microbial aerosols in hospital wards and molecular identification and dissemination of drug resistance of Escherichia coli. Antibiotic-resistant bacteria (ARB) present a global public health problem. Microorganisms are the main cause of hospital-acquired infections, and the biological contamination of hospital environments can cause the outbreak of a series of infectious diseases. Therefore, it is very important to understand the spread of antibiotic-resistant bacteria in hospital environments. This study examines the concentrations of aerobic bacteria and E. coli in ward environments and the airborne transmission of bacterial drug resistance. The results show that the three wards examined have an average aerobic bacterial concentration of 132 CFU∙m(-3) and an average inhalable aerobic bacterial concentration of 73 CFU∙m(-3), with no significant difference (P > 0.05) among the three wards. All isolated E. coli showed multi-drug resistance to not only third-generation cephalosporin antibiotics, but also quinolones, aminoglycosides, and sulfonamides. Furthermore, 51 airborne E. coli strains isolated from the air in the three wards and the corridor were screened for ESBLs, and 12 (23.53%) were ESBL-positive. The drug-resistance gene of the 12 ESBL-positive strains was mainly TEM gene, and the detection rate was 66.67% (8/12). According to a homology analysis with PFGE, 100% homologous E. coli from the ward at 5 m and 10 m outside the ward in the corridor shared the same drug-resistance spectrum, which further proves that airborne E. coli carrying a drug-resistance gene spreads out of the ward through gas exchange. This leads to biological pollution inside, outside, and around the ward, which poses a direct threat to the health of patients, healthcare workers, and surrounding residents. It is also the main reason for the antibiotic resistance in the hospital environment. More attention should be paid to comprehensive hygiene management in the surrounding environment of hospitals.202032070803
3352180.9999Analysis of antibiotic multi-resistant bacteria and resistance genes in the effluent of an intensive shrimp farm (Long An, Vietnam). In Vietnam, intensive shrimp farms heavily rely on a wide variety of antibiotics (ABs) to treat animals or prevent disease outbreak. Potential for the emergence of multi-resistant bacteria is high, with the concomitant contamination of adjacent natural aquatic habitats used for irrigation and drinking water, impairing in turn human health system. In the present study, quantification of AB multi-resistant bacteria was carried out in water and sediment samples from effluent channels connecting a shrimp farming area to the Vam Co River (Long An Province, Vietnam). Bacterial strains, e.g. Klebsiella pneumoniae and Aeromonas hydrophila, showing multi-resistance traits were isolated. Molecular biology analysis showed that these strains possessed from four to seven different AB resistance genes (ARGs) (e.g. sul1, sul2, qnrA, ermB, tetA, aac(6)lb, dfrA1, dfr12, dfrA5), conferring multidrug resistance capacity. Sequencing of plasmids present within these multi-resistant strains led to the identification of a total of forty-one resistance genes, targeting nine AB groups. qPCR analysis on the sul2 gene revealed the presence of high copy numbers in the effluent channel connecting to the Vam Co River. The results of the present study clearly indicated that multi-resistant bacteria present in intensive shrimp cultures may disseminate in the natural environment. This study offered a first insight in the impact of plasmid-born ARGs and the related pathogenic bacteria that could emerged due to inappropriate antibiotic utilization in South Vietnam.201829524670
3314190.9999Carbapenemase and extended-spectrum β-lactamase producing bacteria isolated from municipal wastewater treatment plant and urban river in Nepal. Municipal wastewater treatment plants (WWTPs) and rivers receiving sewage are known hotspots for antibiotic-resistant bacteria (ARB), harboring a wide variety of antibiotic resistance genes (ARGs) and mobile genetic elements. However, the specific distribution of ARB carrying multiple resistance genes in municipal WWTPs and their receiving rivers in Kathmandu remains unclear. Therefore, this study investigated the proportion of antibiotic-resistant bacterial populations and the presence of various ARGs and integrons in carbapenemase- and extended-spectrum β-lactamase (ESBL)-producing bacteria isolated from municipal wastewater and river water. The improvement in water's physicochemical characteristics and a significant reduction in ARB and antibiotic resistance determinants were observed in treated municipal wastewater compared to untreated wastewater. Among 232 bacterial isolates from these samples, 34.82 % were identified as carbapenemase producers, while 42.50 % were confirmed as ESBL producers. E. coli and K. pneumoniae were the predominant carbapenemase- and ESBL-producing bacteria, with their highest abundance in untreated municipal wastewater. Among carbapenemase-producing bacteria, bla (NDM) and bla (OXA) genes were more prevalent, whereas bla (TEM) and bla (CTX-M) genes were commonly detected in ESBL-producing bacteria. Nearly half of these bacterial isolates carried the intI1 gene, indicating its role in the dissemination of ARGs. These findings underscore the critical role of WWTPs in the removal of chemical and biological pollutants, highlighting their significance in urban ecosystem-based adaptation. However, the simultaneous presence of multiple resistance genes and integrons in ARB contributes to the rising antimicrobial resistance in the environment, emphasizing the need for targeted efforts to manage and mitigate the spread of resistance factors.202540979679