Occurrence of β-Lactamase-Producing Gram-Negative Bacterial Isolates in Water Sources in Cali City, Colombia. - Related Documents




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272901.0000Occurrence of β-Lactamase-Producing Gram-Negative Bacterial Isolates in Water Sources in Cali City, Colombia. INTRODUCTION: Pollution by domestic, industrial, and hospital wastes of the artificial and natural waters of the city of Cali led us to investigate the presence of Gram-negative bacteria resistant to antibiotics in these aquatic ecosystems. MATERIAL AND METHODS: We used culture-dependent methods and molecular techniques to investigate the prevalence and dynamics of β-lactamase producing Gram-negative bacteria in five areas located in channels and rivers that cross the city of Cali in January (dry season) and May (wet season). The association between the variables was determined by the chi-square test, using the statistical package SPSS vs 23.0. RESULTS: The main species being Escherichia coli and Pseudomonas spp. with associated resistance to both cefoxitin and cefotaxime were observed in 73.3% isolates during the dry season. Most of the isolates belonged to antibiotype 3 (with resistance to 6 antibiotics), 51.2% in the dry season and 48.9% in the wet season, and they were found especially in the artificial waters of "Intersector Canal (CVC) Sur". CONCLUSION: These results indicate that β-lactamase-producing Gram-negative bacteria are widespread in the environment in the aquatic ecosystem of Cali city. The artificial and natural waters that cross the city are finally discharged into the Rio Cauca; this river can then be considered as a medium for the spread of bacterial antibiotic resistance genes.201931582981
273310.9997Prevalence and diversity of carbapenem-resistant bacteria in untreated drinking water in Portugal. We examined the prevalence and diversity of carbapenem-resistant bacteria (CRB) in untreated drinking water. Prevalence was estimated in plate count agar (PCA) and R2A media with or without antibiotics. Clonal relatedness of isolates was established by repetitive extragenic palindroitic (REP)-PCR. Phylogeny was based on the 16S rRNA gene. Antimicrobial susceptibility was assessed by disc diffusion methods. Genes encoding beta-lactamases and integrases were inspected by PCR. CRB ranged from 0.02% to 15.9% of cultivable bacteria, while ampicillin-resistant bacteria ranged from 1.5% to 31.4%. Carbapenem-resistant isolates affiliated with genera Stenotrophomonas, Pseudomonas, Janthinobacterium, Chryseobacterium, Sphingobacterium, Acidovorax, Caulobacter, Cupriavidus, and Sphingomonas. CRB were highly resistant to beta-lactams, but mostly susceptible to other classes. Transmissible beta-lactamase genes and integrase genes were not detected. The genus-specific bla(L1) was detected in 61% of the Stenotrophomonas isolates. Contrarily to what has been reported for extensively used antibiotics, low levels of carbapenem resistance were detected in untreated drinking water, often represented by intrinsically resistant genera. Production of chromosomal-encoded carbapenemases was the prevalent carbapenem resistance mechanism. Results suggest that the dissemination of anthropogenic-derived carbapenem resistance is at an early stage. This presents an opportunity to rationally develop monitoring strategies to identify dissemination routes and assess the impact of human actions in the environmental resistome.201222663561
286920.9997Antibiotic resistance and antibiotic-resistance genes of Pseudomonas spp. and Escherichia coli isolated from untreated hospital wastewater. Hospitals are considered an important factor in the spread of antibiotic-resistant bacteria (ARBs) and antibiotic-resistance genes (ARGs). The purpose of this research was to characterize the microbial populations in hospital wastewater and investigated the prevalence of β-lactamase, SulІ and QnrS resistance genes. In the first step, culture method was used to isolate Pseudomonas aeruginosa and Escherichia coli. In the next step, accurate identification of isolated bacteria was carried out using the polymerase chain reaction (PCR) method, then the resistance of the bacteria at different concentrations of antibiotics (8-128 μg/mL) was examined. Finally the ARGs were detected using the PCR method. The averages of heterotrophic plate count (HPC) and ARB concentration in wastewater samples were 1.8 × 10(8) and 4.3 × 10(6) CFU/100 mL, respectively. The highest resistance rates were found for sulfamethoxazole and the highest resistance rates in the β-lactamase group were for ceftazidime, while highest sensitivity was for gentamicin and there was no isolate that was sensitive to the studied antibiotics. SulІ and QnrS were the highest and lowest abundance of all ARGs in samples respectively and blaSHV was the highest β-lactam resistance gene. Our results indicated an increase in the resistance of identified bacteria to several antibiotics. So it can be concluded that numerous antibiotic-resistant pathogens and vast numbers of ARGs exist in the human body so that their release from hospitals without effective treatment can cause many dangers to the environment and human health.202134280162
526330.9997Seasonal Variations in Water-Quality, Antibiotic Residues, Resistant Bacteria and Antibiotic Resistance Genes of Escherichia coli Isolates from Water and Sediments of the Kshipra River in Central India. OBJECTIVES: To characterize the seasonal variation, over one year, in water-quality, antibiotic residue levels, antibiotic resistance genes and antibiotic resistance in Escherichia coli isolates from water and sediment of the Kshipra River in Central India. METHODS: Water and sediment samples were collected from seven selected points from the Kshipra River in the Indian city of Ujjain in the summer, rainy season, autumn and winter seasons in 2014. Water quality parameters (physical, chemical and microbiological) were analyzed using standard methods. High-performance liquid chromatography⁻tandem mass spectrometry was used to determine the concentrations of antibiotic residues. In river water and sediment samples, antibiotic resistance and multidrug resistance patterns of isolated E. coli to 17 antibiotics were tested and genes coding for resistance and phylogenetic groups were detected using multiplex polymerase chain reaction. One-way analysis of variance (ANOVA) and Fisher tests were applied to determine seasonal variation. RESULTS: In river water, seasonal variation was significantly associated with various water quality parameters, presence of sulfamethoxazole residues, bacteria resistant to ampicillin, cefepime, meropenem, amikacin, gentamicin, tigecycline, multidrug resistance and CTX-M-1 gene. The majority of the Extended Spectrum Beta-Lactamase (ESBL)-producing E. coli isolates from river water and sediment in all different seasons belonged to phylogenetic group A or B1. CONCLUSIONS: Antibiotic pollution, resistance and resistance genes in the Kshipra River showed significant seasonal variation. Guidelines and regulatory standards are needed to control environmental dissemination of these “pollutants” in this holy river.201829914198
275640.9997Characterization of carbapenem resistance in environmental samples and Acinetobacter spp. isolates from wastewater and river water in Poland. The aim of this study was to analyze the prevalence of carbapenem resistance genes in Acinetobacter spp. isolated from wastewater in a municipal WWTP and to determine their spread from treated wastewater to river water with the use of conventional and molecular microbiology methods (qualitative and quantitative PCR and metagenomic analysis). Samples of untreated and treated wastewater and samples of river water obtained upstream and downstream from the wastewater discharge point were collected in 3 seasons (February, June, and September) of 2019. Acinetobacter spp. isolates were obtained by the culture method on the CHROMagar™ Acinetobacter medium. Additionally, environmental DNA was extracted from the samples for metagenomic and qPCR analyses. The presence of beta-lactam resistance genes (Ambler class B and D), insertion sequence ISAba1, and class I, II, and III integron-integrase genes was determined, and the bacterial taxonomic structure and wastewater and river samples was analyzed. Out of the 301 isolates obtained on the CHROMagar™ Acinetobacter medium, 258 belonged to the genus Acinetobacter, including 21 isolates that were identified as Acinetobacter baumannii. The highest number of Acinetobacter spp. and A. baumannii isolates were obtained from wastewater and river water samples collected in June and September. The ISAba1/bla(OXA-51) complex was identified in 13 isolates, which confirms the occurrence of carbapenem-resistance isolates in the analyzed samples. The number of Acinetobacter isolates carrying antibiotic resistance genes (ARGs) increased in river water samples collected downstream from the wastewater discharge point (48 out of 258 isolates - 18.6%) compared to river water samples collected upstream from the wastewater discharge point (34 out of 258 isolates - 13.2%), which suggests that WWTP is a source of pollution in the natural environment. The conducted research provides evidence that bacteria of the genus Acinetobacter may spread alarming beta-lactam resistance in the environment and, therefore, pose a serious epidemiological threat.202235122847
274650.9997Antibiotic Resistance and Antibiotic Resistance Genes in Escherichia coli Isolates from Hospital Wastewater in Vietnam. The environmental spread of antibiotic-resistant bacteria has been recognised as a growing public health threat for which hospitals play a significant role. The aims of this study were to investigate the prevalence of antibiotic resistance and antibiotic resistance genes (ARGs) in Escherichia coli isolates from hospital wastewater in Vietnam. Wastewater samples before and after treatment were collected using continuous sampling every month over a year. Standard disk diffusion and E-test were used for antibiotic susceptibility testing. Extended-spectrum beta-lactamase (ESBL) production was tested using combined disk diffusion. ARGs were detected by polymerase chain reactions. Resistance to at least one antibiotic was detected in 83% of isolates; multidrug resistance was found in 32%. The highest resistance prevalence was found for co-trimoxazole (70%) and the lowest for imipenem (1%). Forty-three percent of isolates were ESBL-producing, with the bla(TEM) gene being more common than bla(CTX-M). Co-harbouring of the bla(CTX-M), bla(TEM) and qepA genes was found in 46% of isolates resistant to ciprofloxacin. The large presence of antibiotic-resistant E. coli isolates combined with ARGs in hospital wastewater, even post-treatment, poses a threat to public health. It highlights the need to develop effective processes for hospital wastewater treatment plants to eliminate antibiotic resistant bacteria and ARGs.201728661465
275560.9997The Resistome of ESKAPEE Pathogens in Untreated and Treated Wastewater: A Polish Case Study. The aim of this study was to quantify ESKAPEE bacteria, genes encoding resistance to antibiotics targeting this group of pathogens, as well as integrase genes in municipal wastewater and river water. Environmental DNA was extracted from the collected samples and used in deep sequencing with the Illumina TruSeq kit. The abundance of bacterial genera and species belonging to the ESKAPEE group, 400 ARGs associated with this microbial group, and three classes of integrase genes were determined. A taxonomic analysis revealed that Acinetobacter was the dominant bacterial genus, whereas Acinetobacter baumannii and Escherichia coli were the dominant bacterial species. The analyzed samples were characterized by the highest concentrations of the following ARGs: bla(GES), bla(OXA-58), bla(TEM), qnrB, and qnrS. Acinetobacter baumannii, E. coli, and genes encoding resistance to β-lactams (bla(VEB-1), bla(IMP-1), bla(GES), bla(OXA-58), bla(CTX-M), and bla(TEM)) and fluoroquinolones (qnrS) were detected in samples of river water collected downstream from the wastewater discharge point. The correlation analysis revealed a strong relationship between A. baumannii (bacterial species regarded as an emerging human pathogen) and genes encoding resistance to all tested groups of antimicrobials. The transmission of the studied bacteria (in particular A. baumannii) and ARGs to the aquatic environment poses a public health risk.202236009054
273670.9997Characterization of Bacterial Communities and Their Antibiotic Resistance Profiles in Wastewaters Obtained from Pharmaceutical Facilities in Lagos and Ogun States, Nigeria. In Nigeria, pharmaceutical wastewaters are routinely disseminated in river waters; this could be associated with public health risk to humans and animals. In this study, we characterized antibiotic resistant bacteria (ARB) and their antibiotic resistance profile as well as screening for sul1 and sul2 genes in pharmaceutical wastewater effluents. Bacterial composition of the wastewater sources was isolated on non-selective media and characterized by the polymerase chain reaction (PCR) amplification of the 16S rRNA genes, with subsequent grouping using restriction fragment length polymorphism (RFLP) and sequencing. The antibiotics sensitivity profiles were investigated using the standard disk diffusion plate method and the minimum inhibitory concentrations (MICs) of selected antibiotics on the bacterial isolates. A total of 254 bacterial strains were isolated, and majority of the isolates were identified as Acinetobacter sp., Klebsiella pneumonia, Proteus mirabilis, Enterobacter sp. and Bacillus sp. A total of 218 (85.8%) of the bacterial isolates were multidrug resistant. High MICs values were observed for all antibiotics used in the study. The result showed that 31.7%, 21.7% and 43.3% of the bacterial isolates harbored sul1, sul2, and Intl1 genes, respectively. Pharmaceuticals wastewaters are potential reservoirs of ARBs which may harbor resistance genes with possible risk to public health.201829966226
274880.9997Multiresistance, beta-lactamase-encoding genes and bacterial diversity in hospital wastewater in Rio de Janeiro, Brazil. AIMS: To investigate the bacterial diversity, antimicrobial resistance patterns and types of beta-lactamase genes in Gram-negative bacteria isolated from a hospital sewage treatment plant. METHODS AND RESULTS: Between July and December 2008, we collected samples from influent, clarifier tank effluent and chlorine contact tank effluent from a sewage treatment plant service of a hospital located in the city of Rio de Janeiro, Brazil. Of the 221 isolates identified, 40% were characterized as extended-spectrum beta-lactamase (ESBL) producers. Nonpathogenic micro-organisms and some pathogenic genera were quantified. The most common ESBL-producing isolates were Klebsiella pneumoniae, Enterobacter cloacae and Escherichia coli. The bla(TEM), bla(SHV) and bla(CTX-M) genes were detected in 82, 48 and 67% of bacterial isolates, respectively. CONCLUSIONS: Results showed that hospital wastewater treatment plant is not suitable systems for the removal of all antibiotic-resistant micro-organisms present in hospital wastewaters. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence that bacteria resistant to multiple antibiotics and their resistance genes that are usually present in the hospital can reach the environment, even after the use of hospital wastewater treatment plants.201121672095
193990.9997Detection 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
3319100.9997Extended-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
2753110.9996Extended-spectrum beta-lactamase-producing Escherichia coli and antimicrobial resistance in municipal and hospital wastewaters in Czech Republic: Culture-based and metagenomic approaches. Wastewaters serve as important hot spots for antimicrobial resistance and monitoring can be used to analyse the abundance and diversity of antimicrobial resistance genes at the level of large bacterial and human populations. In this study, whole genome sequencing of beta-lactamase-producing Escherichia coli and metagenomic analysis of whole-community DNA were used to characterize the occurrence of antimicrobial resistance in hospital, municipal and river waters in the city of Brno (Czech Republic). Cefotaxime-resistant E. coli were mainly extended-spectrum beta-lactamase (ESBL) producers (95.6%, n = 158), of which the majority carried bla(CTX-M) (98.7%; n = 151) and were detected in all water samples except the outflow from hospital wastewater treatment plant. A wide phylogenetic diversity was observed among the sequenced E. coli (n = 78) based on the detection of 40 sequence types and single nucleotide polymorphisms (average number 34,666 ± 15,710) between strains. The metagenomic analysis revealed a high occurrence of bacterial genera with potentially pathogenic members, including Pseudomonas, Escherichia, Klebsiella, Aeromonas, Enterobacter and Arcobacter (relative abundance >50%) in untreated hospital and municipal wastewaters and predominance of environmental bacteria in treated and river waters. Genes encoding resistance to aminoglycosides, beta-lactams, quinolones and macrolides were frequently detected, however bla(CTX-M) was not found in this dataset which may be affected by insufficient sequencing depth of the samples. The study pointed out municipal treated wastewater as a possible source of multi-drug resistant E. coli and antimicrobial resistance genes for surface waters. Moreover, the combination of two different approaches provided a more holistic view on antimicrobial resistance in water environments. The culture-based approach facilitated insight into the dynamics of ESBL-producing E. coli and the metagenomics shows abundance and diversity of bacteria and antimicrobial resistance genes vary across water sites.202133232750
1953120.9996Antibiotic-Resistant Bacteria and Resistance Genes in Isolates from Ghanaian Drinking Water Sources. The control of infectious diseases is seriously threatened by the increase in the number of microorganisms resistant to antimicrobial agents. Antibiotic-resistant bacteria have also been identified in the water environment. A field study was performed sampling drinking water sources in seven districts of southern Ghana targeting boreholes, dams, hand-dug wells, and streams during baseflow conditions. Bacteria were isolated (N = 110) from a total of 67 water samples to investigate their antimicrobial susceptibility and to determine their carriage of select antibiotic resistance genes. Bacterial identification was performed using conventional selective media methods and the analytical profile index (API) method. Antibiotic susceptibility tests were carried out using the Kirby-Bauer method. Results indicated that all water sources tested were of poor quality based on the presence of fecal indicator organisms. The most commonly occurring bacterium isolated from water was Klebsiella spp. (N = 24, 21.8%), followed by E. coli (N = 23, 20.9%). Gram-negative bacteria isolates were most commonly resistant to cefuroxime (24.5%), while the Gram-positives were most commonly resistant to meropenem (21.3%). The highest rates of bacterial resistances to more than one antibiotic were observed in Klebsiella spp. (30.0%) followed by E. coli (27.8%). PCR was used to detect the presence of a select antibiotic resistance genes in the Gram-negative isolates. The presence of bla (NDM-1), sull, tet(O), and tet(W) were observed in isolates from all water sources. In contrast, ermF was not detected in any of the Gram-negative isolates from any water source. Most (28.7%) of the resistance genes were observed in E. coli isolates. Reducing microbial contamination of the various water sources is needed to protect public health and to ensure the sustainability of this resource. This further calls for education of the citizenry.202236246472
2737130.9996Meropenem-resistant bacteria in hospital effluents in Seoul, Korea. This study aimed to understand the prevalence, diversity, antibiotic resistance, β-lactamase gene types, and possibility of environmental survival of meropenem-resistant bacteria present in hospital effluents in Seoul, Korea. Water sampling was performed at five general hospitals in Seoul, Korea, in January 2017. Water samples were plated in triplicate on tryptic soy agar plates with 16 mg/L meropenem. Meropenem-resistant bacteria were selected and subjected to 16S rRNA analysis for species determination and PCR for identification of β-lactamase gene types. Resistant bacteria were cultured in sterilized surface water. Meropenem-resistant bacteria exhibited resistance to more than 12 antibiotics and possessed several β-lactamase genes, such as those encoding OXT-M, NDM-1, AmpC, and OXA. They were able to multiply and survive in sterilized surface water for up to 60 days. Multidrug-resistant bacteria represent an environmental health risk, as they can survive in the environment for an extended period of time. Therefore, these bacteria should be monitored before discharge.201830361772
1967140.9996Identification of molecular determinants of antibiotic resistance in some fish farms of Ghana. Antimicrobial resistance is a global health challenge caused by the ability of microorganisms including bacteria, fungi, protozoans and viruses to survive the effects of drugs that hitherto were effective against them. This study sought to investigate the presence of antibiotic-resistant bacteria and their corresponding molecular determinants in fish farms of the Central and Western Regions of Ghana. Management practices and antibiotic use at the fish farms were obtained through the administration of a questionnaire. Coliform and Gram-positive bacterial loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus) intestinal microbiota, and pond water samples recovered on MacConkey Agar and Mannitol Salt Agar were determined. Bacterial isolates were identified using various biochemical assays. Antibiotic resistance profiles and possible responsible genes of bacterial isolates were determined using the disc diffusion and Polymerase Chain Reaction (PCR) methods respectively. The study revealed that none of the fish farm managers admitted using antibiotics for prevention and treatment of diseases and no major disease outbreak had ever been recorded. Bacterial loads of pond water exceeded the acceptable level of ≤100 E. coli and <10 coliforms per mL for wastewater recommended for use in fish farming. In all, 145 bacterial isolates comprising 99 Gram negative and 46 Gram-positive bacteria were stored and identified. Most isolates were resistant to at least an antibiotic. Both Gram-negative and Gram-positive bacteria were highly resistant to beta-lactam antibiotics with a corresponding high percentage detection of the bla (TEM) gene compared to other classes of antibiotics. This study has revealed the presence of various molecular determinants of antibiotic resistance including bla (TEM), cmIA, qnrS, tetB and bla (CTX-M), in multidrug-resistant bacteria at some fish farms in Ghana. There is the need to increase awareness about risks associated with the misuse and overuse of antibiotics by humans and the potential risk of spread of multi-drug resistant-bacteria in the environment.202236097488
2750150.9996Extended-spectrum β-lactamases genes in Gram-negative isolates from an urban river in Nicaragua. Limited resources and inadequate surveillance systems in developing countries have hindered research on antibiotic resistance gene transfer in aquatic environments. In this context, our study aimed to identify extended-spectrum beta-lactamase gene variants in Gram-negative isolates from the Tipitapa River-a significant Central America ecosystem. Samples were collected and assessed for key water parameters: dissolved oxygen, electrical conductivity, pH, and temperature. We employed a mix of microbiological, biochemical and molecular techniques, including multiplex PCR and sequencing, to characterize bacteria and determine the bla gene variants. Water quality parameters indicated areas impacted by human activities with high mineralization and eutrophication conditions. Among the bacteria analyzed, 48% belonged to the Enterobacteriaceae family, and a significant 88% displayed extended-spectrum beta-lactamases. Sequencing revealed four distinct bla gene variants in 84% of the isolates: bla-SHV-24, bla-SHV-13, bla-TEM-1, and bla-TEM-116, with bla-SHV-24 being the most common (47.62%). This is the first report of bla gene variants in the Tipitapa River, revealing their presence in globally concerning bacteria. The robust methodology enhances surveillance, enables geographic profiling of bla gene variants, and improves our understanding of biochemical patterns and gene transmission dynamics, providing essential insights into the global distribution of antibiotic resistance genes in Central America's natural waters.202539907335
2858160.9996Antibiotic resistance in fecal sludge and soil in Ho Chi Minh City, Vietnam. This study investigated the prevalence of antibiotic-resistant bacteria and genes in fecal sludge and soil in Ho Chi Minh City, Vietnam, and identified the factors contributing to the survival of antibiotic-resistant bacteria in soil. Sludge and soil samples (n = 24 and 55, respectively) were collected from residential septic systems and environmental reservoirs (i.e., canals, rivers, and parks) in twelve districts of Ho Chi Minh City and tested against a library of 12 antibiotic-resistant genes and 1 integron gene. The susceptibility of isolated Escherichia coli from sludge and soil (n = 104 and 129, respectively) was tested against nine antibiotics. Over 60% of sludge and soil samples harbored sul1, ere(A), intI1, cmIA, and tet(A) genes. The three most common phenotypic resistances found in E. coli isolated from sludge and soil were to ampicillin, tetracycline, and sulfamethoxazole/trimethoprim. In a temporal microcosm study of antibiotic-susceptible and multi-drug-resistant E. coli inoculated in soil, temperature (21.4 vs. 30 °C), resistance phenotype, and soil background microbial community were associated with E. coli decay rates over 73 days. This is the first study that provides insights into the high prevalence of antibiotic resistance in septic systems and environmental reservoirs in Ho Chi Minh City, Vietnam. Findings highlight that the fecal sludge and soil environments in Vietnam are likely reservoirs for dissemination of and human exposure to antibiotic resistance.201931643014
2255170.9996Diversity and metallo-β-lactamase-producing genes in Pseudomonas aeruginosa strains isolated from filters of household water treatment systems. The microbiological quality of drinking water has long been a critical element in public health. Considering the high clinical relevance of Pseudomonas aeruginosa, we examined the filters of household water treatment systems for its presence and characteristics to determine the systems' efficiency in eliminating the bacteria. In total, filters of 50 household water treatment systems were examined. Microbiological and molecular methods were used for the detection and confirmation of P. aeruginosa isolates. Random Amplification of Polymorphic DNA-polymerase chain reaction (RAPD-PCR) was performed to detect similarities and differences among P. aeruginosa isolates. Combined disk (CD) method and double disk synergy test (DDST) were performed to detect metallo-beta-lactamase (MBL)-producing P. aeruginosa isolates. Finally, PCR was performed to detect MBL genes in MBL-producing strains. From the 50 analyzed systems, 76 colonies of P. aeruginosa were identified. In some systems, isolated bacteria from different filters harbored similar genetic profiles, indicating that these isolates may be able to pass through the filter and reach higher filters of the system. Phenotypic tests revealed 7 (9.2%) MBL-producing strains. Two isolates were positive for bla(VIM-1), whereas one isolate was positive for bla(NDM) and bla(IMP-1). The wide distribution of resistant phenotypes and genetic plasticity of these bacteria in household water treatment systems indicate that resistance mechanisms circulate among P. aeruginosa isolates in the environment of the filtration systems. The presence of MBL-producing genes in these systems and P. aeruginosa as a potential reservoir of these resistance genes can be a major concern for public health.201930368151
2868180.9996Detection and Analysis of Drug and Disinfectant Resistance Genes in the Sewage of a Center for Disease Control and Prevention. PURPOSE: Sewage is a significant reservoir for drug and disinfectant resistance genes and a medium for dissemination. This study aimed to evaluate the presence of drug and disinfectant resistance genes in the sewage of a Center for Disease Control and Prevention (CDC) and to assess the risks of their dissemination. METHODS: Sewage from a CDC in Hangzhou was collected, filtered, and enriched, and its microorganisms were cultured. The isolated bacteria were identified, and the minimum inhibitory concentration (MIC) was determined. The drug and disinfectant resistance genes in the sewage and bacteria were detected through polymerase chain reaction amplification. RESULTS: Three kinds of bacteria were isolated from the sewage sample. The MIC for Sphingomonas and Staphylococcus xylosus against chlorine-containing disinfectants was 250 mg/L, whereas the MIC for Bacillus firmus was 500 mg/L. The β-lactam resistance gene TEM and the disinfectant resistance gene qacA were positive in the bacteria, whereas the β-lactam resistance genes TEM, SHV, and VIM-1, the tetracycline resistance gene tetM, the aminoglycoside resistance genes aac(6')/aph(2') and aph3'-III, and the disinfectant resistance genes qacA, qacE, and qacEΔ1 were positive in the sewage. CONCLUSION: Drug and disinfectant resistance genes were found in the sewage of a CDC and were associated with bacteria. Thus, optimizing the monitoring and treatment of sewage is crucial.202540303605
2739190.9996Evaluating the Role of Wastewaters as Reservoirs of Antibiotic-Resistant ESKAPEE Bacteria Using Phenotypic and Molecular Methods. INTRODUCTION: Wastewaters carrying thousands of human specimens from the community and representing the diversity of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) directly from the community mirror the extent of AR spread in the community and environment. This study aimed to investigate the occurrence and distribution of antibiotic-resistant ESKAPEE bacteria in the community versus clinical settings through monitoring nonclinical and clinical wastewaters. METHODOLOGY: Seven wastewater samples were collected from different environmental sources. Isolates were obtained on general and selective media, biochemically characterized and antimicrobial-susceptibility tests performed by disk diffusion against 13 antibiotics according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines using MastDisc disk cartridges, and 16S rRNA metagenomic analysis was performed for two water samples. RESULTS: Of 43 isolates, all representatives of the ESKAPEE group were recovered from clinical wastewaters, but Gram-positive cocci were not obtained from nonclinical wastewaters. The most predominant isolate was Pseudomonas aeruginosa (n=15; 33%), followed by Escherichia coli (n=9; 20%). Complete (100%) resistance to eleven of the tested antibiotics was observed, with only a few isolates being susceptible to clarithromycin, amikacin, and gentamicin. The lowest (79%) resistance rate was observed for linezolid. The multiple antibiotic resistance (MAR) index was calculated, and the resistance phenotype was independent of the wastewater source, indicated by x (2) (P=0.766). Metagenomic analysis replicated the results, as Pseudomonas spp., Acinetobacter spp., and Escherichia spp. were found to be predominant. The integrase gene (IntI1) was also amplified in Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. CONCLUSION: Wastewaters are significant carriers of drug-resistant ESKAPEE bacteria and play an important role in their dissemination. This study endorses the periodic surveillance of water systems to evaluate the presence and burden of antibiotic-resistant pathogens.202236199818