Klebsiella spp. carried by insects as a reservoir of virulence and resistance to antimicrobials. - Related Documents




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163201.0000Klebsiella spp. carried by insects as a reservoir of virulence and resistance to antimicrobials. Synanthropic flies contribute to the transport of pathogens between environments, but their role remains underexplored. Previously, our group described 197 bacterial strains obtained from 117 dipterous muscoids collected nearby hospitals in Rio de Janeiro, 35 % showing antimicrobial resistance. Ten isolates belonged to Klebsiella genus. Klebsiella pneumoniae is a threat to human health due to high resistance and virulence. We characterized the 10 isolates from the genus Klebsiella isolated from flies, comparing to 4 from patients. Most carried resistance determinants as bla (SHV) and bla (NDM). One of them was MDR. Isolates from flies included ST219 and ST76, clinically relevant. Efflux pumps and porins were sporadically encoded in both fly and clinical samples. Among 10 virulence determinants, fly-isolated strains presented from 2 to 7 genes, while clinical strains ranged from 4 to 6. Notably, fly-isolated formed higher biofilm than clinical. Our findings underline that environmental resistance reservoirs may undermine efforts to control AMR.202540630107
168210.9999Multidrug-Resistant and Clinically Relevant Gram-Negative Bacteria Are Present in German Surface Waters. Water is considered to play a role in the dissemination of antibiotic-resistant Gram-negative bacteria including those encoding Extended-spectrum beta-lactamases (ESBL) and carbapenemases. To investigate the role of water for their spread in more detail, we characterized ESBL/Carbapenemase-producing bacteria from surface water and sediment samples using phenotypic and genotypic approaches. ESBL/Carbapenemase-producing isolates were obtained from water/sediment samples. Species and antibiotic resistance were determined. A subset of these isolates (n = 33) was whole-genome-sequenced and analyzed for the presence of antibiotic resistance genes and virulence determinants. Their relatedness to isolates associated with human infections was investigated using multilocus sequence type and cgMLST-based analysis. Eighty-nine percent of the isolates comprised of clinically relevant species. Fifty-eight percent exhibited a multidrug-resistance phenotype. Two isolates harbored the mobile colistin resistance gene mcr-1. One carbapenemase-producing isolate identified as Enterobacter kobei harbored bla (VIM-) (1). Two Escherichia coli isolates had sequence types (ST) associated with human infections (ST131 and ST1485) and a Klebsiella pneumoniae isolate was classified as hypervirulent. A multidrug-resistant (MDR) Pseudomonas aeruginosa isolate encoding known virulence genes associated with severe lung infections in cystic fibrosis patients was also detected. The presence of MDR and clinically relevant isolates in recreational and surface water underlines the role of aquatic environments as both reservoirs and hot spots for MDR bacteria. Future assessment of water quality should include the examination of the multidrug resistance of clinically relevant bacterial species and thus provide an important link regarding the spread of MDR bacteria in a One Health context.201931849911
161920.9998Evidence 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
163130.9998Surveillance of antimicrobial resistant bacteria in flies (Diptera) in Rio de Janeiro city. Antimicrobial-resistant bacteria were isolated from muscoid dipterans collected at five different areas of Rio de Janeiro city, in proximity to hospitals. Extracts obtained by maceration of flies were diluted and used as inocula for different culture media, with or without antibiotic (ceftriaxone 1 mg/L) supplementation. Purified isolates were submitted to antimicrobial susceptibility testing (AST). Bacterial identification was performed by MALDI TOF Microflex LT (Bruker Daltonics). A total of 197 bacterial strains were obtained from 117 dipterous muscoids. Forty-two flies (35.9%) carried bacteria resistant to at least one antimicrobial, while 7 insects (5.9%) carried multidrug-resistant bacteria (MDR), which were all members of the family Enterobacteriaceae. Among 10 MDR bacteria (5%), 5 strains (2,5%) were positive by PCR for one or more of the following antibiotic resistance genes: aac(6')-Ib, bla(TEM-1), bla(CTX-M-15), bla(KPC-2) and bla(NDM-1). Analysis of variance (ANOVA) and cluster analysis compared the number of resistant isolates per collection point and showed that a single location was statistically different from the others with regard to resistance. Although there are still no criteria to determine the environmental contamination by resistant bacteria the fact that they have been isolated from flies is an indication of a disseminated contamination. As such, these insects may be useful in monitoring programs of antibiotic resistance in non-hospital environments, where they could function as sentinels.202134029528
204040.9998Multidrug-resistant bacteria as intestinal colonizers and evolution of intestinal colonization in healthy university students in Portugal. Multidrug-resistant bacteria have been increasingly described in healthcare institutions, however community resistance also seems to be emerging. Escherichia coli an intestinal commensal bacteria, is also a pathogen and represents an important intestinal reservoir of resistance. Our aim was the study of the intestinal colonization and of the persistence of antibiotic resistant intestinal bacteria in healthy university students of Porto, in the north of Portugal. Samples from 30 university students were collected and analysed. Two E. coli isolates were randomly obtained from each student and Gram-negative bacilli resistant to antibiotics were studied. In addition, we evaluated changes in the Gram-negative intestinal colonization of ten university students in a short period of time. Molecular characterization showed a high presence of bla (TEM) in commensal E. coli . Gram-negative bacteria with intrinsic and extrinsic resistance were isolated, namely Pseudomonas spp., Enterobacter spp. and Pantoea spp. We isolated three ESBL-producing E. coli from two students. These isolates showed bla (CTX-M) group 1 (n=1), bla (CTX-M) group 9 (n=2), bla (TEM) (n=2), bla (SHV) (n=1) and tetA (n=2) genes. Additionally, they showed specific virulence factors and conjugational transfer of antibiotic resistance and virulence genes. One Pseudomonas spp. isolate resistant to carbapenems was detected colonizing one student. Our results confirm that healthy young adults may be colonized with commensals showing clinically relevant antibiotic resistance mechanisms, creating a risk of silent spread of these bacteria in the community.202133997613
183150.9998Antibiotic resistance genes in the gut microbiota of mothers and linked neonates with or without sepsis from low- and middle-income countries. Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for bla(CTX-M-15), bla(NDM), bla(KPC) and bla(OXA-48)-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates' rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers' rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.202235927336
170960.9998High prevalence of bla(VIM-1) gene in bacteria from Brazilian soil. This study investigated bacteria from soil samples to (i) determine the main bacterial genera and species having resistance to carbapenem and other β-lactams and (ii) establish if the mechanism of resistance was due to the production of metallo-β-lactamases. The isolates were characterized by PCR for metallo-β-lactamases and integrons, by antimicrobial susceptibility testing, and by sequencing. The antimicrobial profile of 40 imipenem-resistant Gram-positive soil isolates from all Brazilian regions demonstrated that 31 (77.5%) of them were multidrug resistant. Among the 40 isolates, 19 presented the bla(VIM) gene and class 1 integrons by PCR. Six of the 19 isolates were identified as Paenibacillus sp., 12 as Bacillus sp., and just 1 was classified as Staphylococcus sp., by sequencing of the 16S rRNA gene. These results suggest that bacteria from soil can act as a source of bla(VIM-1) genes, representing a threat to public health.201627392282
189970.9998Characteristics of plasmids in multi-drug-resistant Enterobacteriaceae isolated during prospective surveillance of a newly opened hospital in Iraq. BACKGROUND: Gram-negative multidrug-resistant (MDR) bacteria are major causes of nosocomial infections, and antibiotic resistance in these organisms is often plasmid mediated. Data are scarce pertaining to molecular mechanisms of antibiotic resistance in resource constrained areas such as Iraq. METHODOLOGY/PRINCIPAL FINDINGS: In this study, all MDR Enterobacteriaceae (n = 38) and randomly selected non-MDR counterparts (n = 41) isolated from patients, healthcare workers and environmental surfaces in a newly opened hospital in Iraq were investigated to characterize plasmids found in these isolates and determine their contribution to antibiotic resistance. Our results demonstrated that MDR E. coli and K. pneumoniae isolates harbored significantly more (≥ 3) plasmids compared to their non-MDR counterparts, which carried ≤ 2 plasmids (p<0.01). Various large plasmids (~52 to 100 kb) from representative isolates were confirmed to contain multiple resistance genes by DNA microarray analysis. Aminoglycoside (acc, aadA, aph, strA/B, and ksgA), β-lactam (bla(TEM1), bla(AMPC), bla(CTX-M-15), bla(OXA-1), bla(VIM-2) and bla(SHV)), sulfamethoxazole/trimethoprim (sul/dfr), tetracycline (tet) and chloramphenicol (cat) resistance genes were detected on these plasmids. Additionally, multiple plasmids carrying multiple antibiotic resistance genes were found in the same host strain. Genetic transfer-associated genes were identified on the plasmids from both MDR and non-MDR isolates. Seven plasmid replicon types (FII, FIA, FIB, B/O, K, I1 and N) were detected in the isolates, while globally disseminated IncA/C and IncHI1 plasmids were not detected in these isolates. CONCLUSIONS/SIGNIFICANCE: This is the first report of the characteristics of the plasmids found in Enterobacteriaceae isolated following the opening of a new hospital in Iraq. The information provided here furthers our understanding of the mechanisms of drug resistance in this specific region and their evolutionary relationship with other parts of world. The large plasmids, carrying resistance genes and transfer-associated genes, may be potential factors for regional dissemination of antibiotic resistance.201222808141
191280.9998Klebsiella pneumoniae species complex: From wastewater to the environment. Klebsiella pneumoniae plays a significant role in nosocomial infections and spreading antibiotic resistance, and therefore forms a major threat to public health. In this study, we investigated the role of the wastewater pathway in the spread of pathogenic bacteria and more specifically, in the spread of antibiotic resistant Klebsiella pneumoniae subspecies. Whole-genome sequencing was performed of 185 K. pneumoniae isolates collected from hospital, nursing home, and community wastewater, the receiving wastewater treatment plant (WWTP), and clinical isolates from the investigated hospital. K. pneumoniae isolates from different sources were not genetically related, except for WWTP influent (46.5%) and effluent (62.5%), revealing survival of bacteria from wastewater treatment. The content of antibiotic resistance (ARGs), virulence, and plasmid replicon genes differed between K. pneumoniae subspecies and their origin. While chromosomal bla genes were specific for each K. pneumoniae subspecies, bla genes predicted in plasmid contigs were found in several K. pneumoniae subspecies, implying possible gene transfer between subspecies. Transferable ARGs were most abundant in patients and hospital isolates (70%), but the average number of plasmid replicon genes per isolate was similar across all sources, showing plasmid content being more relevant than plasmid quantity. Most patient (90%) and hospital wastewater (34%) isolates were K. pneumoniae subsp. pneumoniae, and the yersiniabactin cluster genes ybt, fyuA, and irp12 were only found in this subspecies, as were the IncFII(pECLA), IncHI2A, and IncHI2 plasmid replicon genes, suggesting the clinical origin of these type of plasmids.202439263320
170890.9998High-level of resistance to β-lactam and presence of β-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from soil. OBJECTIVES: Bacteria belonging to the genera Ochrobactrum and Achromobacter are bacteria considered opportunistic, causing infections mainly in immunocompromised patients. β-lactamases are the main cause of resistance to β-lactam antibiotics. This study aimed to investigate the antimicrobial resistance profile and the presence of β-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from Brazilian soils. METHODS: Soil samples from the five regions of Brazil were collected for the isolation of bacteria, which were identified molecularly and then, the minimum inhibitory concentration and detection of β-lactamases encoding genes were performed. RESULTS: High-level of resistance to β-lactam antibiotics and different β-lactamases encoding genes were found (bla(CTX-M-Gp1), bla(SHV), bla(OXA-1-like) and bla(KPC)), including the first report of the presence of bla(KPC) in bacteria belonging to the genera Ochrobactrum and Achromobacter. CONCLUSION: The results showed that the bacteria from this study, belonging to genera Ochrobactrum and Achromobacter isolated from soil, harbor different β-lactamases encoding genes and can act as a reservoir of these genes.201729111479
1685100.9998Molecular epidemiology and mechanisms of carbapenem and colistin resistance in Klebsiella and other Enterobacterales from treated wastewater in Croatia. Among the most problematic bacteria with clinical relevance are the carbapenem-resistant Enterobacterales (CRE), as there are very limited options for their treatment. Treated wastewater can be a route for the release of these bacteria into the environment and the population. The aim of this study was to isolate CRE from treated wastewater from the Zagreb wastewater treatment plant and to determine their phenotypic and genomic characteristics. A total of 200 suspected CRE were isolated, 148 of which were confirmed as Enterobacterales by MALDI-TOF MS. The predominant species was Klebsiella spp. (n = 47), followed by Citrobacter spp. (n = 40) and Enterobacter cloacae complex (cplx.) (n = 35). All 148 isolates were carbapenemase producers with a multidrug-resistant phenotype. Using multi-locus sequence typing and whole-genome sequencing (WGS), 18 different sequence types were identified among these isolates, 14 of which were associated with human-associated clones. The virulence gene analysis of the sequenced Klebsiella isolates (n = 7) revealed their potential pathogenicity. PCR and WGS showed that the most frequent carbapenemase genes in K. pneumoniae were bla(OXA-48) and bla(NDM-1), which frequently occurred together, while bla(KPC-2) together with bla(NDM-1) was mainly detected in K. oxytoca, E. cloacae cplx. and Citrobacter spp. Colistin resistance was observed in 40% of Klebsiella and 57% of Enterobacter isolates. Underlying mechanisms identified by WGS include known and potentially novel intrinsic mechanisms (point mutations in the pmrA/B, phoP/Q, mgrB and crrB genes) and acquired mechanisms (mcr-4.3 gene). The mcr-4.3 gene was identified for the first time in K. pneumoniae and is probably located on the conjugative IncHI1B plasmid. In addition, WGS analysis of 13 isolates revealed various virulence genes and resistance genes to other clinically relevant antibiotics as well as different plasmids possibly associated with carbapenemase genes. Our study demonstrates the important role that treated municipal wastewater plays in harboring and spreading enterobacterial pathogens that are resistant to last-resort antibiotics.202438479059
2042110.9998Genome Analysis of Multidrug-Resistant Escherichia coli Isolated from Poultry in Nigeria. Escherichia coli is one of the most common commensal bacteria of the gastrointestinal tract of humans and warm-blooded animals. Contaminated poultry can lead to disease outbreaks in consumers causing massive economic losses in the poultry industry. Additionally, commensal E. coli can harbor antibiotic resistance genes that can be transferred to other bacteria, including pathogens, in a colonized human host. In a previous study on antimicrobial resistance of E. coli from food animals from Nigeria, multidrug-resistant E. coli were detected. Three of those isolates were selected for further study using whole-genome sequencing due to the extensive drug resistance exhibited. All of the isolates carried the extended-spectrum β-lactamase (ESBL) genes, bla(CTX-M15) and bla(TEM-1), whereas one isolate harbored an additional ESBL, bla(OXA-1). All of the tetracycline-resistant isolates carried tet(A). The genes aac3-IIa and aacA4, conferring resistance to aminoglycosides, were identified in an E. coli isolate resistant to gentamicin and tobramycin. In two E. coli isolates, dfrA14, qnrS1, and sulII, were detected conferring resistance to trimethoprim, fluoroquinolones, and sulfonamides, respectively. The third isolate carried dfrA17, no fluoroquinolone resistance gene, an additional sulI gene, and a chloramphenicol resistance gene, catB3. Mutations in candidate genes conferring resistance to fosfomycin and fluoroquinolones were also detected. Several efflux systems were detected in all the E. coli isolates and virulence-associated genes related to serum resistance, motility, and adhesion. E. coli and non-E. coli origin prophages were also identified in the isolates. The results underline the higher resolution power of whole-genome sequencing for investigation of antimicrobial resistance, virulence, and phage in E. coli.202031509034
2041120.9998Carrier flies of multidrug-resistant Escherichia coli as potential dissemination agent in dairy farm environment. The life cycle of synanthropic flies and their behavior, allows them to serve as mechanical vectors of several pathogens. Given that flies can carry multidrug-resistant (MDR) bacteria, this study aimed to investigate the spread of genes of antimicrobial resistance in Escherichia coli isolated from flies collected in two dairy farms in Brazil. Besides antimicrobial resistance determinants, the presence of virulence genes related to bovine colibacillosis was also assessed. Of 94 flies collected, Musca domestica was the most frequently found in the two farms. We isolated 198 E. coli strains (farm A=135 and farm B=63), and >30% were MDR E. coli. We found an association between bla(TEM) and phenotypical resistance to ampicillin, or chloramphenicol, or tetracycline; and bla(CTX-M) and resistance to cefoperazone. A high frequency (86%) of phylogenetic group B1 among MDR strains and the lack of association between multidrug resistance and virulence factors suggest that antimicrobial resistance possibly is associated with the commensal bacteria. Clonal relatedness of MDR E. coli performed by Pulsed-Field Gel Electrophoresis showed wide genomic diversity. Different flies can carry clones, but with distinct antimicrobial resistance pattern. Sanger sequencing showed that the same class 1 integron arrangement is displayed by apparently unrelated strains, carried by different flies. Our conjugation results indicate class 1 integron transfer associated with tetracycline resistance. We report for the first time, in Brazil, that MDR E. coli is carried by flies in the milking environment. Therefore, flies can act as carriers for MDR strains and contribute to dissemination routes of antimicrobial resistance.201829758886
1593130.9998Epidemiological 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
1856140.9998Whole-Genome Sequencing-Based Species Classification, Multilocus Sequence Typing, and Antimicrobial Resistance Mechanism Analysis of the Enterobacter cloacae Complex in Southern China. Members of the Enterobacter cloacae complex (ECC) are important opportunistic nosocomial pathogens that are associated with a great variety of infections. Due to limited data on the genome-based classification of species and investigation of resistance mechanisms, in this work, we collected 172 clinical ECC isolates between 2019 and 2020 from three hospitals in Zhejiang, China and performed a retrospective whole-genome sequencing to analyze their population structure and drug resistance mechanisms. Of the 172 ECC isolates, 160 belonged to 9 classified species, and 12 belonged to unclassified species based on ANI analysis. Most isolates belonged to E. hormaechei (45.14%) followed by E. kobei (13.71%), which contained 126 STs, including 62 novel STs, as determined by multilocus sequence typing (MLST) analysis. Pan-genome analysis of the two ECC species showed that they have an "open" tendency, which indicated that their Pan-genome increased considerably with the addition of new genomes. A total of 80 resistance genes associated with 11 antimicrobial agent categories were identified in the genomes of all the isolates. The most prevailing resistance genes (12/29, 41.38%) were related to β-lactams followed by aminoglycosides. A total of 247 β-lactamase genes were identified, of which the bla(ACT) genes were the most dominant (145/247, 58.70%), followed by the bla(TEM) genes (21/247, 8.50%). The inherent ACT type β-lactamase genes differed among different species. bla(ACT-2) and bla(ACT-3) were only present in E. asburiae, while bla(ACT-9), bla(ACT-12), and bla(ACT-6) exclusively appeared in E. kobei, E. ludwigii, and E. mori. Among the six carbapenemase-encoding genes (bla(NDM-1), bla(NDM-5), bla(IMP-1), bla(IMP-4), bla(IMP-26), and bla(KPC-2)) identified, two (bla(NDM-1) and bla(IMP-1)) were identified in an ST78 E. hormaechei isolate. Comparative genomic analysis of the carbapenemase gene-related sequences was performed, and the corresponding genetic structure of these resistance genes was analyzed. Genome-wide molecular characterization of the ECC population and resistance mechanism would offer valuable insights into the effective management of ECC infection in clinical settings. IMPORTANCE The presence and emergence of multiple species/subspecies of ECC have led to diversity and complications at the taxonomic level, which impedes our further understanding of the epidemiology and clinical significance of species/subspecies of ECC. Accurate identification of ECC species is extremely important. Also, it is of great importance to study the carbapenem-resistant genes in ECC and to further understand the mechanism of horizontal transfer of the resistance genes by analyzing the surrounding environment around the genes. The occurrence of ECC carrying two MBL genes also indicates that the selection pressure of bacteria is further increased, suggesting that we need to pay special attention to the emergence of such bacteria in the clinic.202236350178
1621150.9998Antibiotic Resistance and Virulence Profiles of Escherichia coli Strains Isolated from Wild Birds in Poland. Wild animals are increasingly reported as carriers of antibiotic-resistant and pathogenic bacteria including Enterobacteriaceae. However, the role of free-living birds as reservoirs for potentially dangerous microbes is not yet thoroughly understood. In our work, we examined Escherichia coli strains from wild birds in Poland in relation to their antimicrobial agents susceptibility, virulence and phylogenetic affiliation. Identification of E. coli was performed using MALDI-TOF mass spectrometry. The antibiotic susceptibility of the isolates was determined by the broth microdilution method, and resistance and virulence genes were detected by PCR. E. coli bacteria were isolated from 32 of 34 samples. The strains were most often classified into phylogenetic groups B1 (50%) and A (25%). Resistance to tetracycline (50%), ciprofloxacin (46.8%), gentamicin (34.3%) and ampicillin (28.1%) was most frequently reported, and as many as 31.2% of E. coli isolates exhibited a multidrug resistance phenotype. Among resistance genes, sul2 (31.2% of isolates) and bla(TEM) (28.1%) were identified most frequently, while irp-2 (31.2%) and ompT (28.1%) were the most common virulence-associated genes. Five strains were included in the APEC group. The study indicates that wild birds can be carriers of potentially dangerous E. coli strains and vectors for the spread of resistant bacteria and resistance determinants in the environment.202134451523
1683160.9998Colonization of a hand washing sink in a veterinary hospital by an Enterobacter hormaechei strain carrying multiple resistances to high importance antimicrobials. BACKGROUND: Hospital intensive care units (ICUs) are known reservoirs of multidrug resistant nosocomial bacteria. Targeted environmental monitoring of these organisms in health care facilities can strengthen infection control procedures. A routine surveillance of extended spectrum beta-lactamase (ESBL) producers in a large Australian veterinary teaching hospital detected the opportunistic pathogen Enterobacter hormaechei in a hand washing sink of the ICU. The organism persisted for several weeks, despite two disinfection attempts. Four isolates were characterized in this study. METHODS: Brilliance-ESBL selective plates were inoculated from environmental swabs collected throughout the hospital. Presumptive identification was done by conventional biochemistry. Genomes of multidrug resistant Enterobacter were entirely sequenced with Illumina and Nanopore platforms. Phylogenetic markers, mobile genetic elements and antimicrobial resistance genes were identified in silico. Antibiograms of isolates and transconjugants were established with Sensititre microdilution plates. RESULTS: The isolates possessed a chromosomal Tn7-associated silver/copper resistance locus and a large IncH12 conjugative plasmid encoding resistance against tellurium, arsenic, mercury and nine classes of antimicrobials. Clusters of antimicrobial resistance genes were associated with class 1 integrons and IS26, IS903 and ISCR transposable elements. The blaSHV-12, qnrB2 and mcr-9.1 genes, respectively conferring resistance to cephalosporins, quinolones and colistin, were present in a locus flanked by two IS903 copies. ESBL production and enrofloxacin resistance were confirmed phenotypically. The isolates appeared susceptible to colistin, possibly reflecting the inducible nature of mcr-9.1. CONCLUSIONS: The persistence of this strain in the veterinary hospital represented a risk of further accumulation and dissemination of antimicrobial resistance, prompting a thorough disinfection of the ICU. The organism was not recovered from subsequent environmental swabs, and nosocomial Enterobacter infections were not observed in the hospital during that period. This study shows that targeted routine environmental surveillance programs to track organisms with major resistance phenotypes, coupled with disinfection procedures and follow-up microbiological cultures are useful to control these risks in sensitive areas of large veterinary hospitals.202033087168
1618170.9998Molecular Characterization of Multidrug-Resistant Escherichia coli from Fecal Samples of Wild Animals. Antimicrobial resistance (AMR) surveillance in fecal Escherichia coli isolates from wildlife is crucial for monitoring the spread of this microorganism in the environment and for developing effective AMR control strategies. Wildlife can act as carriers of AMR bacteria and spread them to other wildlife, domestic animals, and humans; thus, they have public health implications. A total of 128 Escherichia coli isolates were obtained from 66 of 217 fecal samples obtained from different wild animals using media without antibiotic supplementation. Antibiograms were performed for 17 antibiotics to determine the phenotypic resistance profile in these isolates. Extended-spectrum β-lactamase (ESBL) production was tested using the double-disc synergy test, and 29 E. coli strains were selected for whole genome sequencing. In total, 22.1% of the wild animals tested carried multidrug-resistant E. coli isolates, and 0.93% (2/217) of these wild animals carried E. coli isolates with ESBL-encoding genes (bla(CTX-M-65), bla(CTX-M-55), and bla(EC-1982)). The E. coli isolates showed the highest resistance rates to ampicillin and were fully susceptible to amikacin, meropenem, ertapenem, and imipenem. Multiple resistance and virulence genes were detected, as well as different plasmids. The relatively high frequency of multidrug-resistant E. coli isolates in wildlife, with some of them being ESBL producers, raises some concern regarding the potential transmission of antibiotic-resistant bacteria among these animals. Gaining insights into antibiotic resistance patterns in wildlife can be vital in shaping conservation initiatives and developing effective strategies for responsible antibiotic use.202439453061
1704180.9998Exploring virulence characteristics of Klebsiella pneumoniae isolates recovered from a Greek hospital. The objective of this study was to characterize the virulence characteristics of a collection of Klebsiella pneumoniae isolates collected from different clinical sources. A collection of 60 non-repetitive K. pneumoniae isolates, was studied. In vitro, virulence was analyzed by testing the survival of bacteria in pooled human serum. Isolates were typed by MLST. The genomes of 23 K. pneumoniae isolates, representatives of different STs and virulence profiles, were completely sequenced using the Illumina platform. Of note, 26/60 of K. pneumoniae isolates were resistant to killing by complement. Serum-resistant isolates belonged to distinct STs. Analysis of WGS data with VFDB showed the presence of several virulence genes related various virulence functions. Specifically, serum-resistant isolates carried a higher number of ORFs, which were associated with serum resistance, compared to serum-sensitive isolates. Additionally, analysis of WGS data showed the presence of multiple plasmid replicons that could be involved with the spread and acquisition of resistance and virulence genes. In conclusion, analysis of virulence characteristics showed that an important percentage (31.6%) of K. pneumoniae isolates were in vitro virulent by exhibiting resistance to serum. Thus, the presence of several virulence factors, in combination with the presence of multidrug resistance, could challenge antimicrobial therapy of infections caused by such bacteria.202540415138
869190.9998The Prevalence of Antibiotic Resistance Phenotypes and Genotypes in Multidrug-Resistant Bacterial Isolates from the Academic Hospital of Jaén, Spain. The heterogenicity of antimicrobial resistance genes described in clinically significant bacterial isolates and their potential role in reducing the efficacy of classically effective antibiotics pose a major challenge for global healthcare, especially in infections caused by Gram-negative bacteria. We analyzed 112 multidrug-resistant (MDR) isolates from clinical samples in order to detect high resistance profiles, both phenotypically and genotypically, among four Gram-negative genera (Acinetobacter, Escherichia, Klebsiella, and Pseudomonas). We found that 9.8% of the total selected isolates were classified as extensively drug-resistant (XDR) (six isolates identified as A. baumannii and five among P. pneumoniae isolates). All other isolates were classified as MDR. Almost 100% of the isolates showed positive results for bla(OXA-23) and bla(NDM-1) genes among the A. baumannii samples, one resistance gene (bla(CTX-M)) among E. coli, and two genetic determinants (bla(CTX-M) and aac(6')-Ib) among Klebsiella. In contrast, P. aeruginosa showed just one high-frequency antibiotic resistance gene (dfrA), which was present in 68.42% of the isolates studied. We also describe positive associations between ampicillin and cefotaxime resistance in A. baumannii and the presence of bla(VEB) and bla(GES) genes, as well as between the aztreonam resistance phenotype and the presence of bla(GES) gene in E. coli. These data may be useful in achieving a better control of infection strategies and antibiotic management in clinical scenarios where these multidrug-resistant Gram-negative pathogens cause higher morbidity and mortality.202438786157