First reported detection of the mobile colistin resistance genes, mcr-8 and mcr-9, in the Irish environment. - Related Documents




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276101.0000First reported detection of the mobile colistin resistance genes, mcr-8 and mcr-9, in the Irish environment. The emergence and dissemination of mobile colistin resistance (mcr) genes across the globe poses a significant threat to public health, as colistin remains one of the last line treatment options for multi-drug resistant infections. Environmental samples (157 water and 157 wastewater) were collected in Ireland between 2018 and 2020. Samples collected were assessed for the presence of antimicrobial resistant bacteria using Brilliance ESBL, Brilliance CRE, mSuperCARBA and McConkey agar containing a ciprofloxacin disc. All water and integrated constructed wetland influent and effluent samples were filtered and enriched in buffered peptone water prior to culture, while wastewater samples were cultured directly. Isolates collected were identified via MALDI-TOF, were tested for susceptibility to 16 antimicrobials, including colistin, and subsequently underwent whole genome sequencing. Overall, eight mcr positive Enterobacterales (one mcr-8 and seven mcr-9) were recovered from six samples (freshwater (n = 2), healthcare facility wastewater (n = 2), wastewater treatment plant influent (n = 1) and integrated constructed wetland influent (piggery farm waste) (n = 1)). While the mcr-8 positive K. pneumoniae displayed resistance to colistin, all seven mcr-9 harbouring Enterobacterales remained susceptible. All isolates demonstrated multi-drug resistance and through whole genome sequencing analysis, were found to harbour a wide variety of antimicrobial resistance genes i.e., 30 ± 4.1 (10-61), including the carbapenemases, bla(OXA-48) (n = 2) and bla(NDM-1) (n = 1), which were harboured by three of the isolates. The mcr genes were located on IncHI2, IncFIIK and IncI1-like plasmids. The findings of this study highlight potential sources and reservoirs of mcr genes in the environment and illustrate the need for further research to gain a better understanding of the role the environment plays in the persistence and dissemination of antimicrobial resistance.202336906027
276010.9999Extended-spectrum β-lactamase-producing bacteria and their resistance determinants in different wastewaters and rivers in Nepal. Wastewaters serve as significant reservoirs of antibiotic resistant bacteria. Despite the evidence of antimicrobial resistance in wastewaters and river water in Kathmandu, direct linkage between them is not discussed yet. This study investigated the prevalence of extended-spectrum β-lactamase (ESBL)-producing bacteria and associated resistance genes in wastewaters and river water. Out of 246 bacteria from wastewaters, 57.72% were ESBL producers and 77.64% of them were multidrug resistant (MDR). ESBL producing E. coli was dominant in municipal and hospital wastewaters (HWW) as well as in river water while K. pneumoniae was common in pharmaceutical wastewater. The bla(SHV) and bla(TEM) genes were prevalent and commonly co-occurred with aac(6')-Ib-cr in K. pneumoniae isolated pharmaceutical wastewater. bla(CTX-M) carrying E. coli from hospital co-harbored aac(6')-Ib-cr while that from municipal influent and river water co-harbored qnrS. Whole genome sequencing data revealed the presence of diverse ARGs in bacterial isolates against multiple antibiotics. In average, an E. coli and a K. pneumoniae isolate contained 55.75 ± 0.96 and 40.2 ± 5.36 ARGs, respectively. Multi-locus sequence typing showed the presence of globally high-risk clones with wider host range such as E. coli ST10, and K. pneumoniae ST15 and ST307 in HWW and river indicating frequent dissemination of antimicrobial resistance in wastewater of Kathmandu. Whole genome sequence data aligned with phenotypic antibiograms and resistance genes detected by PCR in selected isolates. The presence of significant plasmid replicons (IncF, IncY) and mobile genetic elements (IS903, IS26) indicate high frequency of spreading antibiotic resistance. These findings indicate burden and dissemination of antimicrobial resistance in the environment and highlight the need for effective strategies to mitigate the antibiotic resistance.202438795483
87820.9999Environmental Spread of New Delhi Metallo-β-Lactamase-1-Producing Multidrug-Resistant Bacteria in Dhaka, Bangladesh. Resistance to carbapenem antibiotics through the production of New Delhi metallo-β-lactamase-1 (NDM-1) constitutes an emerging challenge in the treatment of bacterial infections. To monitor the possible source of the spread of these organisms in Dhaka, Bangladesh, we conducted a comparative analysis of wastewater samples from hospital-adjacent areas (HAR) and from community areas (COM), as well as public tap water samples, for the occurrence and characteristics of NDM-1-producing bacteria. Of 72 HAR samples tested, 51 (71%) samples were positive for NDM-1-producing bacteria, as evidenced by phenotypic tests and the presence of the bla(NDM-1) gene, compared to 5 of 41 (12.1%) samples from COM samples (P < 0.001). All tap water samples were negative for NDM-1-producing bacteria. Klebsiella pneumoniae (44%) was the predominant bacterial species among bla(NDM-1)-positive isolates, followed by Escherichia coli (29%), Acinetobacter spp. (15%), and Enterobacter spp. (9%). These bacteria were also positive for one or more other antibiotic resistance genes, including bla(CTX-M-1) (80%), bla(CTX-M-15) (63%), bla(TEM) (76%), bla(SHV) (33%), bla(CMY-2) (16%), bla(OXA-48-like) (2%), bla(OXA-1) (53%), and bla(OXA-47-like) (60%) genes. Around 40% of the isolates contained a qnr gene, while 50% had 16S rRNA methylase genes. The majority of isolates hosted multiple plasmids, and plasmids of 30 to 50 MDa carrying bla(NDM-1) were self-transmissible. Our results highlight a number of issues related to the characteristics and source of spread of multidrug-resistant bacteria as a potential public health threat. In view of the existing practice of discharging untreated liquid waste into the environment, hospitals in Dhaka city contribute to the potential dissemination of NDM-1-producing bacteria into the community.IMPORTANCE Infections caused by carbapenemase-producing Enterobacteriaceae are extremely difficult to manage due to their marked resistance to a wide range of antibiotics. NDM-1 is the most recently described carbapenemase, and the bla(NDM-1) gene, which encodes NDM-1, is located on self-transmissible plasmids that also carry a considerable number of other antibiotic resistance genes. The present study shows a high prevalence of NDM-1-producing organisms in the wastewater samples from hospital-adjacent areas as a potential source for the spread of these organisms to community areas in Dhaka, Bangladesh. The study also examines the characteristics of the isolates and their potential to horizontally transmit the resistance determinants. The significance of our research is in identifying the mode of spread of multiple-antibiotic-resistant organisms, which will allow the development of containment measures, leading to broader impacts in reducing their spread to the community.201728526792
294930.9998Genomic analysis of multidrug-resistant Escherichia coli strains carrying the mcr-1 gene recovered from pigs in Lima-Peru. Antibiotic resistance is a current problem that significantly impacts overall health. The dissemination of antibiotic resistance genes (ARGs) to urban areas primarily occurs through ARG-carrying bacteria present in the gut microbiota of animals raised in intensive farming settings, such as pig production. Hence, this study aimed to isolate and analyzed 87 Escherichia coli strains from pig fecal samples obtained from intensive farms in Lima Department. The isolates were subjected to Kirby-Bauer-Disk Diffusion Test and PCR for mcr-1 gene identification. Disk-diffusion assay revealed a high level of resistance among these isolates to oxytetracycline, ampicillin, cephalothin, chloramphenicol, ciprofloxacin, and doxycycline. PCR analysis identified the mcr-1 gene in 8% (7/87) E. coli isolates. Further, whole genome sequencing was conducted on 17 isolates, including multidrug resistance (MDR) E. coli and/or mcr-1 gene carriers. This analysis unveiled a diverse array of ARGs. Alongside the mcr-1 gene, the bla(CTX-M55) gene was particularly noteworthy as it confers resistance to third generation cephalosporins, including ceftriaxone. MDR E. coli genomes exhibited other ARGs encoding resistance to fosfomycin (fosA3), quinolones (qnrB19, qnrS1, qnrE1), tetracyclines (tetA, tetB, tetD, tetM), sulfonamides (sul1, sul2, sul3), amphenicols (cmlA1, floR), lincosamides (inuE), as well as various aminoglycoside resistance genes. Additionally, Multi Locus Sequence Typing (MLST) revealed a high diversity of E. coli strains, including ST10, a pandemic clone. This information provides evidence of the dissemination of highly significant ARGs in public health. Therefore, it is imperative to implement measures aimed at mitigating and preventing the transmission of MDR bacteria carrying ARGs to urban environments.202337473695
161340.9998Research note: Occurrence of mcr-encoded colistin resistance in Escherichia coli from pigs and pig farm workers in Vietnam. WHO considers colistin as a highest priority critically important drug for human health, and occurrence of colistin-resistant bacteria in livestock is of health concern. The current study determined occurrence of colistin-resistant Escherichia coli in pigs and workers at pig farms in Vietnam, and investigated the genetic background for resistance. Colistin-resistant E. coli were detected from pigs in 53/116 (45.7%) farms, and from workers taking care of the pigs in 21/94 (22.3%) farms. Colistin-resistant isolates showed MIC to colistin between 4-16 mg/L, they were multidrug resistant (99%) and resistance was caused by the presence of mcr-1 genes in 97/102 (95.1%) E. coli from pigs and in 31/34 (91.1%) isolates from humans. mcr-1 is considered a plasmid-encoded gene, but this was not confirmed in the current investigation. In total, one pig isolate carried both mcr-1 and mcr-3 genes, whereas mcr-2, mcr-4 and mcr-5 genes were not detected. Shared resistance profiles between pig and human isolates on the same farm was only observed in four farms. The study showed that commensal E. coli from pigs in Vietnam constitute a reservoir for colistin-resitant E. coli, however, further studies are needed to confirm that mcr genes are associated with plasmids and their importance for human health.202037333956
100450.9998Hospital Wastes as Potential Sources for Multi-Drug-Resistant ESBL-Producing Bacteria at a Tertiary Hospital in Ethiopia. The hospital environment is increasingly becoming an important reservoir for multi-drug-resistant (MDR) Gram-negative bacteria, posing serious challenges to efforts to combat antimicrobial resistance (AMR). This study aimed to investigate the role of hospital waste as a potential source of MDR ESBL-producing bacteria. Samples were collected from multiple sources within a hospital and its vicinity, including surface swabs, houseflies, and sewage samples. The samples were subsequently processed in a microbiology laboratory to identify potential pathogenic bacteria and confirmed using MALDI-TOF MS. Bacteria were isolated from 87% of samples, with the predominant isolates being E. coli (30.5%), Klebsiella spp. (12.4%), Providencia spp. (12.4%), and Proteus spp. (11.9%). According to the double disc synergy test (DDST) analysis, nearly half (49.2%) of the bacteria were identified as ESBL producers. However, despite exhibiting complete resistance to beta-lactam antibiotics, 11.8% of them did not test positive for ESBL production. The characterization of E. coli revealed that 30.6% and 5.6% of them carried blaCTX-M group 1 type-15 and blaNDM genes, respectively. This finding emphasizes the importance of proper hospital sanitation and waste management practices to mitigate the spread of AMR within the healthcare setting and safeguard the health of both patients and the wider community.202438667050
262360.9998High Carriage of Extended-Spectrum, Beta Lactamase-Producing, and Colistin-Resistant Enterobacteriaceae in Tibetan Outpatients with Diarrhea. Antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) have been detected in human-impacted habitats, especially in densely populated cities. The Qinghai-Tibet Plateau is located far from the heavily populated regions of China, and Tibetan residents have distinct dietary habits and gut microbes. Antibiotic-resistance monitoring in the Tibetan population is rare. Here, we collected stool samples from Tibetan outpatients with diarrhea. From 59 samples, 48 antibiotic-resistant Enterobacteriaceae isolates were obtained, including 19 extended-spectrum beta lactamase (ESBL)-producing isolates from 16 patients and 29 polymyxin-resistant isolates from 22 patients. Either ESBL or mcr genes were found in 17 Escherichia coli isolates, approximately 58.8% of which were multidrug-resistant, and ten incompatible plasmid types were found. The gene bla(CTX-M) was a common genotype in the ESBL-producing E. coli isolates. Four E. coli isolates contained mcr-1. The same mcr-1-carrying plasmid was found in distinct E. coli isolates obtained from the same sample, thus confirming horizontal transmission of mcr-1 between bacteria. Genomic clustering of E. coli isolates obtained from Lhasa, with strains from other regions providing evidence of clone spreading. Our results reveal a strong presence of ARB and ARGs in Tibetan outpatients with diarrhea, implying that ARB and ARGs should be monitored in the Tibetan population.202235453259
87770.9998Drug resistance analysis of three types of avian-origin carbapenem-resistant Enterobacteriaceae in Shandong Province, China. Animal-derived Enterobacteriaceae bacteria such as Escherichia coli (E. coli), Proteus mirabilis (P. mirabilis), and Klebsiella pneumoniae (K. pneumoniae) are important food-borne zoonotic bacilli that exist widely in the broiler-breeding industry. Although carbapenem antibiotics are considered to be the last line of defense against multidrug-resistant bacteria, carbapenem-resistant Enterobacteriaceae (CRE) break through them. In our study, we therefore, examined the prevalence of CRE and characteristics of antimicrobial resistance in 6 conventional broiler-fattening farms in Shandong Province, China. Our study revealed isolation rates of 3.57% (6/168) for carbapenem-resistant E. coli, 10% (5/50) for carbapenem-resistant P. mirabilis, and 3.03% (1/33) for carbapenem-resistant K. pneumoniae. All 12 CRE bacterial strains showed varying degrees of resistance to 27 antibiotics in 8 classes and were multidrug-resistant. The rate of the strains containing bla(NDM) genes, at 91.67% (11/12), was especially high. Among other results, the carrying rate of integrons in CRE bacteria was 91.67% (11/12), and 2 strains carried both class I and class II integrons, which accelerated the lateral transmission of resistant bacteria. Our first-ever finding of the 3 CRE bacteria E. coli, P. mirabilis, and K. pneumoniae on the same broiler farm suggests that poultry-derived CRE strains may pose a risk to humans. Moreover, our findings from surveillance can inform current understandings of the prevalence and characteristics of multidrug-resistant CRE in Shandong Province and, in turn, help to curb threats to food safety and public health and better prevent and control infectious zoonotic diseases.202336682131
261380.9998Antibiotic-Resistant Enterobacteriaceae in Wastewater of Abattoirs. Antibiotic-resistant Enterobacteriaceae are regularly detected in livestock. As pathogens, they cause difficult-to-treat infections and, as commensals, they may serve as a source of resistance genes for other bacteria. Slaughterhouses produce significant amounts of wastewater containing antimicrobial-resistant bacteria (AMRB), which are released into the environment. We analyzed the wastewater from seven slaughterhouses (pig and poultry) for extended-spectrum β-lactamase (ESBL)-carrying and colistin-resistant Enterobacteriaceae. AMRB were regularly detected in pig and poultry slaughterhouse wastewaters monitored here. All 25 ESBL-producing bacterial strains (19 E. coli and six K. pneumoniae) isolated from poultry slaughterhouses were multidrug-resistant. In pig slaughterhouses 64% (12 of 21 E. coli [57%] and all four detected K. pneumoniae [100%]) were multidrug-resistant. Regarding colistin, resistant Enterobacteriaceae were detected in 54% of poultry and 21% of pig water samples. Carbapenem resistance was not detected. Resistant bacteria were found directly during discharge of wastewaters from abattoirs into water bodies highlighting the role of slaughterhouses for environmental surface water contamination.202134065908
89890.9998Characterisation of mobile colistin resistance genes (mcr-3 and mcr-5) in river and storm water in regions of the Western Cape of South Africa. BACKGROUND: Colistin is regarded as a last-resort antimicrobial against multi-drug resistant Gram-negative bacteria (GNB), therefore the dissemination of colistin resistance in the environment is of great concern. Horizontal transfer of mobile colistin resistance (mcr) genes to potential pathogens poses a serious problem. This study aimed to describe the presence of colistin resistant GNB and mcr genes in river and storm water in regions of the Western Cape. METHODS: Water samples were collected from three rivers during May 2019 and January 2020 and two storm water samples were collected in November 2019. Colistin resistant GNB were cultured on MacConkey agar containing colistin and identified by MALDI-TOF. Colistin resistance was confirmed using broth microdilution (BMD). mcr-1-5 genes were detected by PCR performed directly on the water samples and on the colistin resistant isolates. mcr functionality was assessed by BMD after cloning the mcr genes into pET-48b(+) and expression in SHuffle T7 E. coli. RESULTS: mcr-5.1 and various mcr-3 gene variants were detected in the Plankenburg-, Eerste- and Berg rivers and in storm water from Muizenberg, and only mcr-5.1 was detected in storm water from Fish Hoek. Colistin resistant GNB were isolated from all of the water sources. Aeromonas spp. were the most common colistin resistant organisms detected in the water sources; 25% (6/24) of colistin resistant Aeromonas spp. isolated from the Berg river contained novel mcr-3 variants; mcr-3.33 (n = 1), mcr-3.34 (n = 1) mcr-3.35 (n = 1) mcr-3.36 (n = 2) and mcr-3.37 (n = 1), which were confirmed to confer colistin resistance. CONCLUSIONS: The mcr-5.1 and mcr-3 colistin resistance gene variants were present in widely dispersed water sources in regions of the Western Cape. The mcr genes were only detected in water sampled downstream of and alongside communities, suggesting that their presence is driven by human influence/contamination. This is the first documentation of mcr-3 and mcr-5 gene variants in any setting in South Africa. Spill-over of these genes to communities could result in horizontal gene transfer to pathogenic bacteria, exacerbating the challenge of controlling multidrug resistant GNB infections.202134187559
2610100.9998Antimicrobial Resistant Salmonella in Canal Water in Bangkok, Thailand: Survey Results Between 2016 and 2019. Antimicrobial resistance (AMR) in environmental reservoirs is an emerging global health concern, particularly in urban settings with inadequate wastewater management. This study aimed to investigate the prevalence and resistance profiles of Salmonella spp. in canal water in Bangkok and assess the distribution of key antibiotic resistance genes (ARGs). Between 2016 and 2019, a total of 1381 water samples were collected from 29 canals. Salmonella spp. were isolated using standard microbiological methods and tested for susceptibility to 13 antibiotics. Polymerase chain reaction (PCR) was used to detect extended-spectrum β-lactamase (ESBL) genes and class 1 integron. Salmonella was found in 89.7% of samples. Among these, 62.1% showed resistance to at least one antimicrobial, and 54.8% were multidrug-resistant (MDR). The highest resistance was observed against streptomycin (41.4%). ESBL genes, predominantly blaCTX-M, were detected in 72.2% of tested isolates, while class 1 integrons were found in 67.8%, indicating a strong potential for gene dissemination. The results highlight urban canals as critical environment reservoirs of AMR Salmonella serovars, posing significant public health risks, particularly where canal water is used for agriculture, household, or recreational purposes. Strengthened environmental surveillance and effective wastewater regulation are urgently needed to mitigate AMR bacteria transmission at the human-environment-animal interface.202541007477
2628110.9998Occurrence and persistence of multidrug-resistant Enterobacterales isolated from urban, industrial and surface water in Monastir, Tunisia. The One Health approach of antimicrobial resistance highlighted the role of the aquatic environment as a reservoir and dissemination source of resistance genes and resistant bacteria, especially due to anthropogenic activities. Resistance to extended-spectrum cephalosporins (ESC) conferred by extended-spectrum beta-lactamases (ESBLs) in E. coli has been proposed as the major marker of the AMR burden in cross-sectoral approaches. In this study, we investigated wastewater, surface water and seawater that are subjected to official water quality monitoring in Monastir, Tunisia. While all but one sample were declared compliant according to the official tests, ESC-resistant bacteria were detected in 31 (19.1 %) samples. Thirty-nine isolates, coming from urban, industrial and surface water in Monastir, were collected and characterized using antibiograms and whole-genome sequencing. These isolates were identified as 27 Escherichia coli (69.3 %) belonging to 13 STs, 10 Klebsiella pneumoniae (25.6 %) belonging to six STs, and two Citrobacter freundii (5.1 %). We observed the persistence and dissemination of clones over time and in different sampling sites, and no typically human-associated pathogens could be identified apart from one ST131. All isolates presented a bla(CTX-M) gene - bla(CTX-M-15) (n = 22) and bla(CTX-M-55) (n = 8) being the most frequent variants - which were identified on plasmids (n = 20) or on the chromosome (n = 19). In conclusion, we observed ESC resistance in rather ubiquitous bacteria that are capable of surviving in the water environment. This suggests that including the total coliform count and the ESBL count as determined by bacterial growth on selective plates in the official monitoring would greatly improve water quality control in Tunisia.202438460700
2759120.9998Emergence of Carbapenemase Genes in Gram-Negative Bacteria Isolated from the Wastewater Treatment Plant in A Coruña, Spain. Wastewater treatment plants (WWTPs) are recognized as important niches of antibiotic-resistant bacteria that can be easily spread to the environment. In this study, we collected wastewater samples from the WWTP of A Coruña (NW Spain) from April 2020 to February 2022 to evaluate the presence of Gram-negative bacteria harboring carbapenemase genes. Bacteria isolated from wastewater were classified and their antimicrobial profiles were determined. In total, 252 Gram-negative bacteria carrying various carbapenemase genes were described. Whole-genome sequencing was conducted on 55 selected carbapenemase producing isolates using Oxford Nanopore technology. This study revealed the presence of a significant population of bacteria carrying carbapenemase genes in WWTP, which constitutes a public health problem due to their risk of dissemination to the environment. This emphasizes the usefulness of WWTP monitoring for combating antibiotic resistance. Data revealed the presence of different types of sequences harboring carbapenemase genes, such as bla(KPC-2), bla(GES-5), bla(GES-6), bla(IMP-11), bla(IMP-28), bla(OXA-24), bla(OXA-48), bla(OXA-58), bla(OXA-217), and bla(VIM-2). Importantly, the presence of the bla(KPC-2) gene in wastewater, several months before any clinical case was detected in University Hospital of A Coruña, suggests that wastewater-based epidemiology can be used as an early warning system for the surveillance of antibiotic-resistant bacteria.202438391580
2627130.9998High Prevalence of Drug Resistance and Class 1 Integrons in Escherichia coli Isolated From River Yamuna, India: A Serious Public Health Risk. Globally, urban water bodies have emerged as an environmental reservoir of antimicrobial resistance (AMR) genes because resistant bacteria residing here might easily disseminate these traits to other waterborne pathogens. In the present study, we have investigated the AMR phenotypes, prevalent plasmid-mediated AMR genes, and integrons in commensal strains of Escherichia coli, the predominant fecal indicator bacteria isolated from a major urban river of northern India Yamuna. The genetic environment of bla (CTX-M-15) was also investigated. Our results indicated that 57.5% of the E. coli strains were resistant to at least two antibiotic classes and 20% strains were multidrug resistant, i.e., resistant to three or more antibiotic classes. The multiple antibiotic resistance index of about one-third of the E. coli strains was quite high (>0.2), reflecting high contamination of river Yamuna with antibiotics. With regard to plasmid-mediated AMR genes, bla (TEM-1) was present in 95% of the strains, followed by qnrS1 and armA (17% each), bla (CTX-M-15) (15%), strA-strB (12%), and tetA (7%). Contrary to the earlier reports where bla (CTX-M-15) was mostly associated with pathogenic phylogroup B2, our study revealed that the CTX-M-15 type extended-spectrum β-lactamases (ESBLs) were present in the commensal phylogroups A and B1, also. The genetic organization of bla (CTX-M-15) was similar to that reported for E. coli, isolated from other parts of the world; and ISEcp1 was present upstream of bla (CTX-M-15). The integrons of classes 2 and 3 were absent, but class 1 integron gene intI1 was present in 75% of the isolates, denoting its high prevalence in E. coli of river Yamuna. These evidences indicate that due to high prevalence of plasmid-mediated AMR genes and intI1, commensal E. coli can become vehicles for widespread dissemination of AMR in the environment. Thus, regular surveillance and management of urban rivers is necessary to curtail the spread of AMR and associated health risks.202133633708
1619140.9998Evidence of colistin resistance genes (mcr-1 and mcr-2) in wild birds and its public health implication in Egypt. BACKGROUND: Antimicrobial resistance has become one of the most severe global threats to human and veterinary Medicine. colistin is an effective therapeutic agent against multi-drug-resistant pathogens. However, the discovery of transferable plasmids that confer resistance to colistin (mcr-1) has led to challenges in medical science. This study describes the role of wild birds in the harbouring and environmental spread of colistin-resistant bacteria, which could pose a potential hazard to human and animal health. METHODS: In total, 140 faecal samples from wild birds (migratory and resident birds) were tested. Twenty surface water samples were collected from the area in which wild bird trapping was conducted, and 50 human stool samples were collected from individuals residing near the surface water sources and farm buildings. Isolation and identification of Enterobacteriaceae and Pseudomonas aeruginosa from the different samples were performed using conventional culture techniques and biochemical identification. PCR amplification of the mcr genes was performed in all positive isolates. Sequencing of mcr-1 genes from three randomly selected E. coli carrying mcr-1 isolates; wild birds, water and humans was performed. RESULT: The bacteriological examination of the samples showing isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and P. aeruginosa. The results of multiplex PCR of the mcr genes revealed that E. coli was the most prevalent gram-negative bacterium harbouring the mcr genes, whereas a low prevalence was observed for K. pneumoniae. The prevalence of mcr-1 in resident birds, migratory birds, water sources and humans were 10.4, 20,16.6 and 9.6% while the prevalence of mcr-2 were 1.4, 3.6, 11.1 and 9.6%, respectively. Sequencing of the mcr-1 gene from the three E. coli carrying mcr-1 isolates indicated a possible correlation between the wild bird and surface water isolates. CONCLUSION: The detection of mcr-1-positive bacteria in wild birds in Egypt indicates the possible environmental dissemination of this gene through bird activity. The impact of the interaction between domestic and wild animals on public health cannot be overlooked.201931827778
1637150.9998Genomic surveillance of antimicrobial resistance in bovine fecal samples from Lebanon. Antimicrobial resistance (AMR) threatens human and animal health worldwide, driven by the spread of extended-spectrum β-lactamase (ESBL)-producing, and carbapenem-resistant Gram-negative bacteria. In Lebanon, inadequate surveillance and antibiotic misuse worsen the issue. Animal fecal material is an important reservoir of resistance genes and mobile elements. This study aims to address AMR in bovine feces. To achieve this, bovine fecal samples were collected from 24 farms in Lebanon. Sixty-two ESBL-producing bacteria were recovered on CHROMagar ESBL and whole-genome sequencing followed by in silico typing was used to determine the resistance genes, virulence factors, and mobile genetic elements. Disk diffusion assay revealed the prevalence of multidrug-resistant (MDR) Gram-negative bacteria (33/62) with Escherichia coli being the most common (37/62). Resistance to amoxicillin, ceftriaxone, and cefotaxime was detected in all 37 E. coli isolates, with one also exhibiting resistance to colistin. β-lactam resistance was primarily associated with bla(CTX-M-15) and bla(TEM-1B), while colistin resistance was linked to mcr-1.1 on an IncHI2A/IncFIC multi-replicon plasmid. Plasmid typing identified 22 replicons, the most common being IncFIB and IncFII. Virulence factor analysis identified enterotoxin-encoding genes in one E. coli isolate, suggesting a potentially pathogenic strain with diarrheagenic properties among the recovered isolates. The findings of this study revealed highly resistant Gram-negative bacteria with plasmid-mediated resistance to critical antibiotics such as colistin, emphasizing the risks posed to human and livestock health. Comprehensive surveillance and responsible antibiotic use, guided by an integrated One Health approach, are essential steps to effectively tackle the interconnected challenges of AMR.202540482361
2947160.9998Large-Scale Studies on Antimicrobial Resistance and Molecular Characterization of Escherichia coli from Food Animals in Developed Areas of Eastern China. Widely distributed multidrug-resistant (MDR) bacteria threaten animals and human health. Nevertheless, few antimicrobial resistance (AMR) surveys of large-scale animal-derived bacteria have been explored. Here, 1,468 (97.54%) Escherichia coli strains were isolated from 1,505 pig (1,060) and chicken (445) anal swab samples from 11 cities in Zhejiang Province, China, in 2020. These isolates had a high resistance to tetracycline (92.92%), sulfisoxazole (93.05%), florfenicol (83.11%), and ampicillin (78.27%). More than 88.68% of the strains were MDR bacteria. A low AMR ratio to the "last-resort" antimicrobials tigecycline (0.75%), colistin (1.36%), and meropenem (0.75%) were found. The AMR of E. coli from pigs was higher than that of chickens. Eighteen strains among 31 MDR strains that were resistant to "last-resort" antimicrobials could transfer the AMR genes (mcr-1, tet(X), and bla(NDM)) to the recipient strain J53, which confer colistin, tigecycline, and carbapenem resistance, respectively. The homology among mcr-1-carrying isolates was relatively high, and the sequence types were mainly ST5529, ST101, and ST354, while the homology of isolates harboring tet(X4) and bla(NDM-5) genes were different. The mcr-1, bla(NDM-5), and tet(X4) genes in strains LS45, JH51, and TZ118 were identified on the Incl2, IncHI2, and IncX1 plasmids, respectively. Moreover, tet(A), sul2, floR, and bla(TEM-1B) were the most common ARGs in 31 strains. Additionally, the heavy metals copper and zinc had a significant correlation with amoxicillin/clavulanate and tetracycline resistance. Controlling the movement of animals between cities and reducing the use of antimicrobials are effective methods to reduce the threat of AMR bacteria. IMPORTANCE Pigs and chickens are the most common food animals that are the important vectors for spreading antimicrobial-resistant pathogens among animals and humans. Limited systematic AMR monitoring of these food animal origin bacteria had been reported, especially in developed areas of China. Our study provides a comprehensive and systematic study of AMR in Escherichia coli from eastern China. The AMR of E. coli strains among the animals or cities has statistically significant differences. Moreover, the mcr-1, tet(X4), and bla(NDM-5) genes, considered resistant to the last line of AMR, were identified in part of farms. The transferability and the prevalence of these AMR strains were intensively studied. Our monitoring is comparable to human clinical research and has an essential reference for public health safety. These findings will provide early warning for AMR strains and guide the clinical use of antibiotics to control the spread of antibiotic resistance.202235950758
1629170.9998Molecular detection of colistin resistance genes (mcr-1 to mcr-5) in human vaginal swabs. OBJECTIVE: Colistin resistance has emerged worldwide and has been threatening the efficacy of one of the last-resort antimicrobials used for treatment of multidrug resistant Gram-negative bacteria. While five colistin resistance genes (mcr-1, mcr-2, mcr-3, mcr-4 and mcr-5) have been described, few data are available on the prevalence of mcr-genes other than mcr-1 in human samples. RESULTS: In this study, the presence of five currently described colistin resistance genes (mcr 1-5) in vaginal swabs of women undergoing infertility evaluation was reported. Most samples were found to be positive for the mcr-4 (12.7%), followed by two for the mcr-2 (1.5%), two for the mcr-3 (1.5%), one for the mcr-1 (0.7%), and one for the mcr-5 (0.7%). Phylogenetic comparison demonstrated identical (mcr-1, mcr-2, mcr-3, mcr-5) or similar (mcr-4) nucleotide sequences of human samples and those of animal origins from the same city, suggesting the potential transmission of mcr genes from animals to humans. This is the first detection of mcr-2, mcr-4 and mcr-5 genes in human samples, and warrants further research to determine the spread of the mcr genes and elucidate the full epidemiology of colistin resistance genes in humans.201829463301
1913180.9998Citrobacter 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
2624190.9998Dissemination of ESBL-producing Escherichia coli of chicken origin to the nearby river water. The dissemination of drug-resistant bacteria from animal farms to aquatic environments can pose a potential threat to public health. In this study, antimicrobial resistance, resistance genes, and genetic similarity of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli of different origins (chicken feces and upstream and downstream river waters) were analyzed to track the spread of drug-resistant bacteria of animals. The results showed that a total of 29 ESBL-producing E. coli were obtained from 258 samples, and isolation rates of the ESBL-producing E. coli from chicken feces and upstream and downstream waters were 10.7% (16/150), 3.7% (1/27), and 14.8% (12/81), respectively. The ESBL-producing E. coli from upstream water was resistant to 7 antibiotics, but isolates from feces and downstream water had a higher resistance rate. In 29 ESBL-producing E. coli, the most common gene was CTX-M and the SHV gene was not detected. Five ESBL-producing isolates from downstream water showed >90% similarity with the fecal isolates, while the only one isolate from upstream water had <70% similarity with fecal isolates. The results suggest that animal farms' effluent, especially the untreated wastewater, could contribute to the spread of resistance genes.201425277838