Extended-spectrum β-lactamases genes in Gram-negative isolates from an urban river in Nicaragua. - Related Documents




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275001.0000Extended-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
275310.9999Extended-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
274920.9999Culture-independent methods reveal high diversity of OXA-48-like genes in water environments. The carbapenemase OXA-48 was identified for the first time in 2001 and is now one of the greatest concerns in terms of antibiotic resistance. While many studies report clinical OXA-48-like producers, few reports refer bla(OXA-48-like) genes in environmental bacteria. The main goal of this study was to evaluate the diversity of bla(OXA-48-like) genes in aquatic systems, using culture-independent approaches. For that, environmental DNA was obtained from riverine and estuarine water and used to construct clone libraries of bla(OXA-48-like) gene polymerase chain reaction amplicons. bla(OXA-48-like) libraries from river and estuarine water DNA comprised 75 and 70 clones, respectively. Sequence analysis showed that environmental bla(OXA-48-like) genes show a broader diversity than that so far observed in clinical settings. In total, 50 new OXA-48 variants were identified as well as sequences identical to previously reported OXA-48, OXA-181, OXA-199, OXA-204 and OXA-162. Though we have no evidence that these genes were carried by bacteria that are members of the natural heterotrophic flora or bacteria that have entered this particular water environment through anthropogenic sources, these results reinforce the role of aquatic systems as antibiotic resistance reservoirs. The variants of bla(OXA-48) here described should be taken into account when designing molecular strategies for detecting this gene.201728771149
275230.9998Antibiotic Resistance in Enterobacteriaceae from Surface Waters in Urban Brazil Highlights the Risks of Poor Sanitation. Surface waters are an unappreciated reservoir of antimicrobial resistance (AMR). Poor sanitation brings different species of environmental bacteria into contact, facilitating horizontal gene transfer. To investigate the role of surface waters as potential reservoirs of AMR, we studied the point prevalence of fecal contamination, AMR genes, and Enterobacteriaceae in an urban lake and rural river system in Northeast Brazil in comparison with a lake and sewer system in Northeast Ohio in the United States. Surface water samples were examined for evidence of human fecal contamination using microbial source tracking and screened for plasmid-mediated fluoroquinolone resistance and carbapenemase genes. Enterobacteriaceae were detected using selective agar followed by antimicrobial susceptibility testing and detection of AMR genes by microarray, and classified by repetitive sequence-based polymerase chain reaction and multilocus sequence typing. Concentrations of human fecal bacteria in the Brazilian urban lake and sewage in Northeast Ohio were similarly high. Filtered water samples from the Brazilian urban lake, however, showed the presence of bla (OXA-48), bla (KPC), bla (VIM-2), qnrS, and aac(6')-lb-cr, whereas only bla (VIM-2) was identified in raw sewage from Northeast Ohio. From the Brazilian urban lake, 85% of the Enterobacteriaceae (n = 40) cultured were resistant to at least one clinically important antibiotic, including ST131 Escherichia coli harboring the extended-spectrum beta-lactamase CTX-M. Although two isolates demonstrated polymyxin resistance, mcr-1/2 was not detected. Our findings indicate that surface waters in an urban Brazilian site can serve as an environmental reservoir of AMR and that improving wastewater treatment and sanitation generally may ameliorate AMR dissemination.201930994094
191340.9998Citrobacter spp. and Enterobacter spp. as reservoirs of carbapenemase bla(NDM) and bla(KPC) resistance genes in hospital wastewater. Antibiotic resistance has emerged as a global threat to public health, generating a growing interest in investigating the presence of antibiotic-resistant bacteria in environments influenced by anthropogenic activities. Wastewater treatment plants in hospital serve as significant reservoirs of antimicrobial-resistant bacteria, where a favorable environment is established, promoting the proliferation and transfer of resistance genes among different bacterial species. In our study, we isolated a total of 243 strains from 5 hospital wastewater sites in Mexico, belonging to 21 distinct Gram-negative bacterial species. The presence of β-lactamase was detected in 46.9% (114/243) of the isolates, which belonging to the Enterobacteriaceae family. We identified a total of 169 β-lactamase genes; bla(TEM) in 33.1%, bla(CTX-M) in 25.4%, bla(KPC) in 25.4%, bla(NDM) 8.8%, bla(SHV) in 5.3%, and bla(OXA-48) in 1.1% distributed in 12 different bacteria species. Among the 114 of the isolates, 50.8% were found to harbor at least one carbapenemase and were discharged into the environment. The carbapenemase bla(KPC) was found in six Citrobacter spp. and E. coli, while bla(NDM) was detected in two distinct Enterobacter spp. and E. coli. Notably, bla(NDM-1) was identified in a 110 Kb IncFII conjugative plasmid in E. cloacae, E. xiangfangensis, and E. coli within the same hospital wastewater. In conclusion, hospital wastewater showed the presence of Enterobacteriaceae carrying a high frequency of carbapenemase bla(KPC) and bla(NDM). We propose that hospital wastewater serves as reservoirs for resistance mechanism within bacterial communities and creates an optimal environment for the exchange of this resistance mechanism among different bacterial strains. IMPORTANCE: The significance of this study lies in its findings regarding the prevalence and diversity of antibiotic-resistant bacteria and genes identified in hospital wastewater in Mexico. The research underscores the urgent need for enhanced surveillance and prevention strategies to tackle the escalating challenge of antibiotic resistance, particularly evident through the elevated frequencies of carbapenemase genes such as bla(KPC) and bla(NDM) within the Enterobacteriaceae family. Moreover, the identification of these resistance genes on conjugative plasmids highlights the potential for widespread transmission via horizontal gene transfer. Understanding the mechanisms of antibiotic resistance in hospital wastewater is crucial for developing targeted interventions aimed at reducing transmission, thereby safeguarding public health and preserving the efficacy of antimicrobial therapies.202439012101
182750.9998Multinational comparison of the detection of extended-spectrum beta-lactamase genes in healthy resident feces. The spread of antimicrobial-resistant bacteria, especially in developing countries, is a critical healthcare issue. Among these, extended-spectrum beta-lactamase (ESBL)-producing bacteria are particularly concerning due to their resistance to third- and fourth-generation cephalosporins. Traditional methods for assessing bacterial resistance involve culturing bacteria on selective media from fecal samples, which may lead to selection bias. Alternatively, real-time PCR allows for detecting resistance genes directly from fecal DNA, providing a broader view of resistant bacteria. In this study, we evaluated the utility of a real-time PCR assay targeting ESBL-producing genes as a comprehensive detection method for ESBL-producing resistant bacteria in fecal samples. Additionally, we conducted a multinational comparative analysis of the colonization status of residents using this approach. The study analyzed ESBL genes in fecal samples from 161 residents in four countries: Ecuador, Ghana, Vietnam, and Japan. Samples from Ecuador, Ghana, and Vietnam, where ESBL carriage was notably high, revealed gene variations by country, with blaTEM genes being most common except in Ghana, where blaSHV genes predominated. These variations suggest that different bacterial hosts carry ESBL genes across countries. Quantitative PCR results further highlight that blaTEM is the most abundant ESBL gene. Although gene presence does not confirm antibiotic resistance, these findings underline significant ESBL carriage in low- and middle-income countries. The study emphasizes that gene detection in fecal samples is valuable for understanding resistant bacteria spread in communities.IMPORTANCEThe rise of antimicrobial-resistant bacteria, particularly extended-spectrum beta-lactamase (ESBL)-producing strains, poses a serious threat to healthcare in developing countries. This study utilized real-time PCR to detect ESBL genes directly from fecal DNA of 161 participants across four countries, offering a comprehensive analysis without the biases of traditional culture-based methods. High ESBL gene carriage rates were found in Ecuador, Ghana, and Vietnam, with regional differences in gene prevalence: blaTEM dominated in most countries, while blaSHV was most frequent in Ghana. These results highlight the widespread community-level dissemination of ESBL genes in low- and middle-income countries, underscoring the importance of using gene detection as a tool for assessing the spread of resistant bacteria.202540304472
275460.9998Antimicrobial resistance in Aeromonas species isolated from aquatic environments in Brazil. AIM: The current study was conducted to determine the antimicrobial resistance profile and genetic relatedness of Aeromonas sp. isolated from healthcare and urban effluents, wastewater treatment plant (WWTP) and river water. METHODS AND RESULTS: We detected the presence of genes conferring resistance to β-lactam, quinolone and aminoglycoside. Multilocus sequence typing was carried out to differentiate the strains, and multilocus phylogenetic analysis was used to identify the species. A total of 28 cefotaxime-resistant Aeromonas sp. strains were identified, harbouring uncommon Guiana-extended-spectrum (GES)-type β-lactamases (GES-1, GES-5, GES-7 and GES-16). Multidrug-resistant Aeromonas sp. were found in hospital wastewater, WWTP and sanitary effluent, and A. caviae was identified as the most prevalent species (85·7%). CONCLUSION: The release of untreated healthcare effluents, presence of antimicrobials in the environment, in addition to multidrug-resistant Aeromonas sp., are all potential factors for the spread of resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: We identified a vast repertoire of antimicrobial resistance genes (ARG) in Aeromonas sp. from diverse aquatic ecosystems, including those that encode enzymes degrading broad-spectrum antimicrobials widely used to treat healthcare-associated infections. Hospital and sanitary effluents serve as potential sources of bacteria harbouring ARG and are a threat to public health.202133306232
159270.9998Identification of ESBL-Producing Enterobacterales From Vegetable Plants: Preliminary Findings From a Small Cross-Sectional Study in a Rural Area of Madagascar. Extended-spectrum beta-lactamases (ESBL)-producing enterobacterales are considered a key indicator for antimicrobial resistance (AMR) epidemiological surveillance in animal, human, and environment compartments. In this study, we aim to investigate the presence and genetic diversity of ESBL-producing enterobacterales on vegetable plants. We isolated beta-lactam resistant enterobacterales from several vegetable plants and sequenced their whole genome. Utilising standard genomic and phylogenetic methods, we sought to (i) characterise the resistance genes and plasmid content of the plant-isolated strains, (ii) investigate their genetic structure, and (iii) determine their relationships with strains from other reservoirs. Among the 22 strains collected from vegetable plants, 6 showed resistance to beta-lactam antibiotics, with 5 of them identified as ESBL producers. Our results indicated the presence of multidrug-resistant (MDR) strains containing multiple antibiotic resistance genes (ARGs). Importantly, no host-specific lineages were identified among the plant-isolated ESBL-producing E. coli (ESBL-Ec). Instead, these strains exhibited genetic and epidemiological connections with strains isolated from animals, humans, and the environment, suggesting transfer of ESBL-Ec between plants and other sources in rural Madagascar. These preliminary findings suggest that vegetable plants are contaminated as a result of human activities, posing a potential risk of human and animal exposure to antibiotic-resistant bacteria and genes.202540528688
331380.9998The 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
159390.9998Epidemiological Description and Detection of Antimicrobial Resistance in Various Aquatic Sites in Marseille, France. Antibiotic resistance is a worldwide public health concern and has been associated with reports of elevated mortality. According to the One Health concept, antibiotic resistance genes are transferrable to organisms, and organisms are shared among humans, animals, and the environment. Consequently, aquatic environments are a possible reservoir of bacteria harboring antibiotic resistance genes. In our study, we screened water and wastewater samples for antibiotic resistance genes by culturing samples on different types of agar media. Then, we performed real-time PCR to detect the presence of genes conferring resistance to beta lactams and colistin, followed by standard PCR and gene sequencing for verification. We mainly isolated Enterobacteriaceae from all samples. In water samples, 36 Gram-negative bacterial strains were isolated and identified. We found three extended-spectrum β-lactamase (ESBL)-producing bacteria-Escherichia coli and Enterobacter cloacae strains-harboring the CTX-M and TEM groups. In wastewater samples, we isolated 114 Gram-negative bacterial strains, mainly E. coli, Klebsiella pneumoniae, Citrobacter freundii and Proteus mirabilis strains. Forty-two bacterial strains were ESBL-producing bacteria, and they harbored at least one gene belonging to the CTX-M, SHV, and TEM groups. We also detected carbapenem-resistant genes, including NDM, KPC, and OXA-48, in four isolates of E. coli. This short epidemiological study allowed us to identify new antibiotic resistance genes present in bacterial strains isolated from water in Marseille. This type of surveillance shows the importance of tracking bacterial resistance in aquatic environments. IMPORTANCE Antibiotic-resistant bacteria are involved in serious infections in humans. The dissemination of these bacteria in water, which is in close contact with human activities, is a serious problem, especially under the concept of One Health. This study was done to survey and localize the circulation of bacterial strains, along with their antibiotic resistance genes, in the aquatic environment in Marseille, France. The importance of this study is to monitor the frequency of these circulating bacteria by creating and surveying water treatments.202336976002
2836100.9998Waste water effluent contributes to the dissemination of CTX-M-15 in the natural environment. OBJECTIVES: Multidrug-resistant Enterobacteriaceae pose a significant threat to public health. We aimed to study the impact of sewage treatment effluent on antibiotic resistance reservoirs in a river. METHODS: River sediment samples were taken from downstream and upstream of a waste water treatment plant (WWTP) in 2009 and 2011. Third-generation cephalosporin (3GC)-resistant Enterobacteriaceae were enumerated. PCR-based techniques were used to elucidate mechanisms of resistance, with a new two-step PCR-based assay developed to investigate bla(CTX-M-15) mobilization. Conjugation experiments and incompatibility replicon typing were used to investigate plasmid ecology. RESULTS: We report the first examples of bla(CTX-M-15) in UK river sediment; the prevalence of bla(CTX-M-15) was dramatically increased downstream of the WWTP. Ten novel genetic contexts for this gene were identified, carried in pathogens such as Escherichia coli ST131 as well as indigenous aquatic bacteria such as Aeromonas media. The bla(CTX-M-15) -gene was readily transferable to other Gram-negative bacteria. We also report the first finding of an imipenem-resistant E. coli in a UK river. CONCLUSIONS: The high diversity and host range of novel genetic contexts proves that evolution of novel combinations of resistance genes is occurring at high frequency and has to date been significantly underestimated. We have identified a worrying reservoir of highly resistant enteric bacteria in the environment that poses a threat to human and animal health.201424797064
2577110.9998Molecular Detection of bla(TEM) and bla(SHV) Genes in ESBL-Producing Acinetobacter baumannii Isolated from Antarctic Soil. The phenomenon of antimicrobial resistance (AMR) in cold environments, exemplified by the Antarctic, calls into question the assumption that pristine ecosystems lack clinically significant resistance genes. This study examines the molecular basis of AMR in Acinetobacter spp. Isolated from Antarctic soil, focusing on the bla(TEM) and bla(SHV) genes associated with extended-spectrum beta-lactamase (ESBL) production; Soil samples were collected and processed to isolate Antarctic soil bacteria. Molecular detection was then conducted using polymerase chain reaction (PCR) to identify the bacteria species by 16S rRNA/rpoB and 10 different beta-lactamase-producing genes. PCR amplicons were sequenced to confirm gene identity and analyze genetic variability. Acinetobacter baumannii were identified by both microbiological and molecular tests. Notably, both the bla(TEM) and bla(SHV) genes encoding the enzymes responsible for resistance to penicillins and cephalosporins were identified, indicating the presence of resistance determinants in bacteria from extreme cold ecosystems. The nucleotide sequence analysis indicated the presence of conserved ARGs, which suggest stability and the potential for horizontal gene transfer within microbial communities. These findings emphasize that AMR is not confined to human-impacted environments but can emerge and persist in remote, cold habitats, potentially facilitated by natural reservoirs and global microbial dispersal. Understanding the presence and role of AMR in extreme environments provides insights into its global dissemination and supports the development of strategies to mitigate the spread of resistance genes in both environmental and clinical contexts.202540142377
2741120.9998ESKAPE Bacteria and Extended-Spectrum-β-Lactamase-Producing Escherichia coli Isolated from Wastewater and Process Water from German Poultry Slaughterhouses. The wastewater of livestock slaughterhouses is considered a source of antimicrobial-resistant bacteria with clinical relevance and may thus be important for their dissemination into the environment. To get an overview of their occurrence and characteristics, we investigated process water (n = 50) from delivery and unclean areas as well as wastewater (n = 32) from the in-house wastewater treatment plants (WWTPs) of two German poultry slaughterhouses (slaughterhouses S1 and S2). The samples were screened for ESKAPE bacteria (Enterococcus spp., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) and Escherichia coli Their antimicrobial resistance phenotypes and the presence of extended-spectrum-β-lactamase (ESBL), carbapenemase, and mobilizable colistin resistance genes were determined. Selected ESKAPE bacteria were epidemiologically classified using different molecular typing techniques. At least one of the target species was detected in 87.5% (n = 28/32) of the wastewater samples and 86.0% (n = 43/50) of the process water samples. The vast majority of the recovered isolates (94.9%, n = 448/472) was represented by E. coli (39.4%), the A. calcoaceticus-A. baumannii (ACB) complex (32.4%), S. aureus (12.3%), and K. pneumoniae (10.8%), which were widely distributed in the delivery and unclean areas of the individual slaughterhouses, including their wastewater effluents. Enterobacter spp., Enterococcus spp., and P. aeruginosa were less abundant and made up 5.1% of the isolates. Phenotypic and genotypic analyses revealed that the recovered isolates exhibited diverse resistance phenotypes and β-lactamase genes. In conclusion, wastewater effluents from the investigated poultry slaughterhouses exhibited clinically relevant bacteria (E. coli, methicillin-resistant S. aureus, K. pneumoniae, and species of the ACB and Enterobacter cloacae complexes) that contribute to the dissemination of clinically relevant resistances (i.e., bla(CTX-M) or bla(SHV) and mcr-1) in the environment.IMPORTANCE Bacteria from livestock may be opportunistic pathogens and carriers of clinically relevant resistance genes, as many antimicrobials are used in both veterinary and human medicine. They may be released into the environment from wastewater treatment plants (WWTPs), which are influenced by wastewater from slaughterhouses, thereby endangering public health. Moreover, process water that accumulates during the slaughtering of poultry is an important reservoir for livestock-associated multidrug-resistant bacteria and may serve as a vector of transmission to occupationally exposed slaughterhouse employees. Mitigation solutions aimed at the reduction of the bacterial discharge into the production water circuit as well as interventions against their further transmission and dissemination need to be elaborated. Furthermore, the efficacy of in-house WWTPs needs to be questioned. Reliable data on the occurrence and diversity of clinically relevant bacteria within the slaughtering production chain and in the WWTP effluents in Germany will help to assess their impact on public and environmental health.202032033950
1591130.9998Influence of agricultural practice on mobile bla genes: IncI1-bearing CTX-M, SHV, CMY and TEM in Escherichia coli from intensive farming soils. Many calls have been made to address antibiotic resistance in an environmental perspective. With this study, we showed the widespread presence of high-level antibiotic resistant isolates on a collection of non-susceptible Gram-negative bacteria (n = 232) recovered from soils. Bacteria were selected using amoxicillin, cefotaxime and imipenem, from sites representing different agricultural practices (extensive, intensive and organic). Striking levels of non-susceptibility were noticed in intensive soils for norfloxacin (74%), streptomycin (50.7%) and tetracycline (46.6%); indeed, the exposure to intensive agricultural practices constituted a risk factor for non-susceptibility to many antibiotics, multidrug resistance and production of extended-spectrum β-lactamases (ESBL). Analyses of non-susceptibility highlighted that environmental and clinical bacteria from the same species might not share the same intrinsic resistance patterns, raising concerns for therapy choices in environment-borne infections. The multiple sequence-type IncI1-driven spread of penicillinases (blaTEM-1, blaTEM-135), ESBL (blaSHV-12 and blaCTX-M-1) and plasmid-mediated AmpC β-lactamases (blaCMY-2), produced by isolates that share their molecular features with isolates from humans and animals, suggests contamination of agricultural soils. This is also the first appearance of IncI1/ST28-harbouring blaCTX-M-1, which should be monitored to prevent their establishment as successfully dispersed plasmids. This research may help disclose paths of contamination by mobile antibiotic resistance determinants and the risks for their dissemination.201626279315
1711140.9998Detection of β-lactamase encoding genes in feces, soil and water from a Brazilian pig farm. β-lactam antibiotics are widely used for the treatment of different types of infections worldwide and the resistance to these antibiotics has grown sharply, which is of great concern. Resistance to β-lactams in gram-negative bacteria is mainly due to the production of β-lactamases, which are classified according to their functional activities. The aim of this study was to verify the presence of β-lactamases encoding genes in feces, soil, and water from a Brazilian pig farm. Different β-lactamases encoding genes were found, including bla(CTX-M-Gp1), bla(CTX-M-Gp9), bla(SHV), bla(OXA-1-like), bla(GES), and bla(VEB). The bla(SHV) and bla(CTX-M-Gp1) genes have been detected in all types of samples, indicating the spread of β-lactam resistant bacteria among farm pigs and the environment around them. These results indicate that β-lactamase encoding genes belonging to the cloxacillinase, ESBL, and carbapenemase and they have high potential to spread in different sources, due to the fact that genes are closely related to mobile genetic elements, especially plasmids.201829322334
2571150.9998Multidrug-resistant Enterobacter spp. in wastewater and surface water: Molecular characterization of β-lactam resistance and metal tolerance genes. Among the ESKAPE group pathogens, Enterobacter spp. is an opportunistic Gram-negative bacillus, widely dispersed in the environment, that causes infections. In the present study, samples of hospital wastewater, raw and treated urban wastewater, as well as surface receiving water, were collected to assess the occurrence of multidrug-resistant (MDR) Enterobacter spp. A molecular characterization of β-lactam antibiotic resistance and metal tolerance genes was performed. According to identification by MALDI-TOF MS, 14 isolates were obtained: 7 E. bugandensis, 5 E. kobei, and 2 E. cloacae. The isolates showed resistance mainly to β-lactam antibiotics, including those used to treat infections caused by MDR bacteria. Multiple antibiotic resistance index was calculated for all isolates. It allowed verify whether sampling points showed a high risk due to antibiotic resistant Enterobacter spp., as well as to determine if the isolates have been in environments with a frequent antibiotic use. Twelve isolates showed β-lactam antibiotic resistance gene, being the bla(KPC) widely detected. Regarding metal tolerance, 13 isolates showed at least two genes that encode metal tolerance mechanisms. Overall, metal tolerance mechanisms to silver, copper, mercury, arsenic and tellurium were found. New data on metal tolerance mechanisms dispersion and antibiotic-resistance characterization of the E. bugandensis and E. kobei species were here provided. The occurrence of MDR Enterobacter spp. in analyzed samples draws attention to an urgent need to put control measures into practice. It also evidences waterborne spread of clinically important antibiotic-resistant bacteria recognized as critical priority pathogens.202337356524
2745160.9998Dissemination of multi-resistant Gram-negative bacteria into German wastewater and surface waters. Carbapenem antibiotics constitute the mainstay therapy of nosocomial infections with extended spectrum beta-lactamase producing Gram-negative bacteria; however, resistance against these compounds is increasing. This study was designed to demonstrate that carbapenemase-producing bacteria are disseminated from hospitals into the environment. To this end, resistant bacteria were isolated from a clinical/urban and from a rural catchment system in Germany in 2016/17. The study followed the dissemination of resistant bacteria from the wastewater through the wastewater treatment plant (WWTP) into the receiving surface waters. The bacteria were cultivated on selective agar and characterized by antibiotic testing, real-time PCR targeting carbapenemase genes and typing. Bacteria with resistance to third generation cephalosporins were isolated from all sample sites. 134 isolates harboring carbapenemase genes encoding VIM, NDM and OXA-48 and 26 XDR (extensively drug-resistant) strains with susceptibility to only one or two antibiotics were isolated from the clinical/urban system. The rural system yielded eight carbapenemase producers and no XDR strains. In conclusion, clinical wastewaters were charged with a high proportion of multidrug resistant bacteria. Although most of these bacteria were eliminated during wastewater treatment, dissemination into surface waters is possible as single carbapenemase producers were still present in the effluent of the WWTP.201829659796
2734170.9998High Frequency of Antibiotic Resistance Genes (ARGs) in the Lerma River Basin, Mexico. The spread of beta-lactamase-producing bacteria is of great concern and the environment has been found to be a main source of contamination. Herein, it was proposed to determine the frequency of antimicrobial-resistant-Gram-negative bacteria throughout the Lerma River basin using phenotypic and molecular methods. Resistant bacteria were isolated with chromogenic media and antimicrobial susceptibility tests were used to characterize their resistance. ARGs for beta-lactams, aminoglycosides, and quinolones were detected by PCR. Species were identified by Sanger sequencing the 16S rRNA gene and the representative genomes of MDR strains were sequenced by NGS. A high variation in the number of isolates was observed in the 20 sampled sites, while observing a low diversity among the resistant bacteria. Of the 12 identified bacterial groups, C. freundii, E. coli, and S. marcescens were more predominant. A high frequency of resistance to beta-lactams, quinolones, and aminoglycosides was evidenced, where the bla(CTX,)qnrB, qnrS y, and aac(6')lb-cr genes were the most prevalent. C. freundii showed the highest frequency of MDR strains. Whole genome sequencing revealed that S. marcescens and K. pneumoniae showed a high number of shared virulence and antimicrobial resistance genes, while E. coli showed the highest number of unique genes. The contamination of the Lerma River with MDR strains carrying various ARGs should raise awareness among environmental authorities to assess the risks and regulations regarding the optimal hygienic and sanitary conditions for this important river that supports economic activities in the different communities in Mexico.202236360888
1594180.9998Production of extended-spectrum beta-lactamases in Escherichia coli isolated from poultry in Rio de Janeiro, Brazil. The overuse of antimicrobials in poultry has led to the development and dissemination of multidrug-resistant bacteria in the poultry industry. One of the most effective mechanisms of resistance found in Escherichia coli is the production of extended-spectrum β-lactamases (ESBL); there are several ESBLs, including the TEM, SHV, and CTX-M families. This resistance mechanism and the risks associated with transmitting these resistant microorganisms between animals, the environment, and humans can occur through direct contact and consumption of infected animals. This study aimed to determine the prevalence of E. coli in samples isolated from three broiler farms in Rio de Janeiro, Brazil, and screen the isolates for ESBL genes. The findings of this study demonstrated the presence of ESBL-producing E. coli in all farms studied. The findings of this study highlight the urgency for a program to monitor the poultry industry value chains at the regional level to control the spread of antimicrobial resistance. Therefore, we recommend that the enzyme subtypes produced by bacterial isolates should be determined to effectively characterize the distribution of genes related to antimicrobial resistance.202236533205
3311190.9998Appearance of mcr-9, bla(KPC), cfr and other clinically relevant antimicrobial resistance genes in recreation waters and sands from urban beaches, Brazil. The co-occurrence of mcr-like and carbapenemase-encoding genes have been reported mainly in humans and animals, whereas, in the environment, studies are gradually increasing due to the One Health approach. In this study, we investigated antimicrobial resistance genes (ARGs) in water and sand samples from marine environments in Brazil. Total DNA from 56 samples (33 sands and 23 waters) was obtained and 27 different ARGs were detected, highlighting the presence of mcr-9, bla(KPC) and cfr genes. Additionally, the microbiological analysis revealed that sand samples of all analyzed beaches were not recommended for primary use, whereas water samples from most beaches were classified as unsuitable for bathing. The presence of clinically relevant ARGs in urban beaches suggests the presence of antimicrobial-resistant bacteria. Furthermore, to the best of our knowledge, this is the first report of mcr-9 and cfr genes in the environment from Brazil and recreational areas worldwide.202133839570