Search Results (401)

Acinetobacter baumannii is a critical priority ESKAPE pathogen whose resistome co-occurrence architecture, temporal dynamics, and One Health distribution remain poorly characterized. A total of 20,739 genomes (2000–2025; NCBI, PubMLST, BV-BRC) were annotated using CARD-RGI v6.0.5, AMRFinderPlus v4.2.7, and ResFinder v4.7.2. A co-occurrence network was constructed using Jaccard filtering (≥10%; >0.30) with Bayesian bootstrap and Louvain. Temporal trends were assessed by linear regression with Benjamini–Hochberg (2003–2024), and One Health compartments were assessed using balanced PERMANOVA (Bray–Curtis, 999 permutations). The network comprised 41 nodes and 82 edges with a small-world topology; five communities and nine hub genes were identified. Eighteen ARGs showed significant trends (FDR); six last-resort determinants (blaOXA-23-like, blaNDM, armA, ftsI, msr(E), mph(E)) increased in prevalence. The compartment explained significant variance in the resistome (R² = 0.210; p < 0.001). abaF showed the highest One Health convergence (0.814), and blaNDM was detected in 52 countries. The A. baumannii resistome exhibits a convergent architecture of co-resistance: a small-world network preserved in One Health compartments for more than two decades. The rise in six last-resort determinants signals a population-based transition toward broader profiles, establishing a framework for integrated antimicrobial resistance surveillance. Full article

Carbapenem-resistant Enterobacterales (CRE) are a major public health concern, yet genomic data from Bulgaria remain limited. We investigated the genomic epidemiology and genomic characteristics of clinically significant CRE recovered at University Hospital “Lozenetz”, Sofia, between 2022 and 2025. Antimicrobial susceptibility testing, phenotypic carbapenemase characterization, and PCR were combined with whole-genome sequencing of 23 purposively selected isolates chosen to capture temporal, species, carbapenemase, specimen, ward, and resistance-phenotype diversity. The proportion of CRE among all Enterobacterales remained broadly stable over the study period, and Klebsiella pneumoniae was the predominant species throughout. NDM-type carbapenemases were the most frequent overall, although VIM-, KPC-, and OXA-48-like enzymes were also detected. Among the sequenced isolates K. pneumoniae ST6260 (n = 16) was predominant. The remaining isolates included single K. pneumoniae isolates belonging to ST11, ST101, and ST258; two Enterobacter hormaechei ST114; one Proteus mirabilis ST93; and one Providencia stuartii ST46. All ST6260 isolates carried chromosomal blaNDM-5 within a conserved multidrug-resistance module with variable downstream regions, whereas blaOXA-232 was situated on a small ColKP3 plasmid within a defined subcluster. Overall, the data indicate that ST6260 is an emerging hospital-associated multidrug-resistant lineage. Full article

Background/Objectives: Hospital water and wastewater environments are potential reservoirs for antimicrobial resistance genes (ARGs), particularly in high-risk clinical units. This study examined site-specific ARG DNA detection patterns in wet and waste-associated sites of a haematology ward and an intensive care unit (ICU) to identify environmental hotspots that may inform targeted infection prevention and control (IPC) interventions. Methods: A descriptive point-prevalence environmental study was conducted in May 2025 in a tertiary acute-care hospital. Samples were collected after routine cleaning and during usual clinical activity. Real-time PCR assays were used to detect bla_TEM, bla_SHV, bla_CTX-M, bla_OXA-48-like, bla_VIM, bla_NDM, bla_IMP, bla_KPC, and mcr-1. Analytical summaries included samples meeting predefined quality-control criteria. Ct signals were categorised descriptively; Ct values ≤ 40 were considered positive, with Ct values 36–40 classified as very low molecular signals, whereas Ct values > 40 were considered negative. Results: The analytical dataset comprised 60 samples: 31 from haematology and 29 from ICU. At least one included ARG signal was detected in 40/60 samples (66.7%), including 23/31 haematology samples (74.2%) and 17/29 ICU samples (58.6%), bla_TEM (51.7%) and bla_SHV (43.3%) were most frequent. Sink drains showed the broadest multi-gene profiles, especially combinations of ESBL- and carbapenemase-associated genes. Haematology showed broader carbapenemase-associated diversity, whereas ICU detections clustered in patient-room sink drains and sluice-room wastewater infrastructure. Conclusions: ARG DNA signals were unevenly distributed, with sink drains representing most frequently positive sampling sites for multi-gene detection. This molecular, single-timepoint environmental study does not demonstrate viable organisms, colonisation, or transmission; however, point-prevalence environmental assessments may identify wet and wastewater-associated hotspots that can inform targeted IPC interventions against the spread of multidrug-resistant microorganisms. Full article

Background: Bacteria of the genus Providencia are emerging pathogens associated with a wide range of infections, particularly in healthcare settings. In veterinary medicine, infections caused by these organisms are uncommon, and, to date, there have been no reports of carbapenem-resistant Providencia spp. causing infection in companion animals. Methods and Results: This study describes a comprehensive investigation of bacterial endocarditis caused by carbapenem-resistant Providencia rettgeri in a cat, including clinical, imaging, pathological, microbiological, and genomic findings. A 1.5-year-old mixed-breed female cat was admitted to a referral veterinary hospital with an extensive pelvic limb wound and a recent history of laparotomy. During hospitalization, a heart murmur was detected, and echocardiographic examination revealed vegetation-like lesion on the mitral valve. Despite intensive treatment, the patient’s clinical condition progressively deteriorated over a 15-day period, ultimately leading to euthanasia. Necropsy confirmed bacterial endocarditis with evidence of systemic septic embolization. P. rettgeri was isolated from blood collected from both heart ventricles and from an endocardial swab and its identity was confirmed by MALDI-ToF mass spectrometry. Antimicrobial susceptibility testing demonstrated resistance to meropenem. Whole-genome sequencing confirmed the species identification and revealed a Col3M plasmid carrying multiple antimicrobial resistance genes, including the carbapenemase gene bla_NDM-1. Discussion: To the best of our knowledge, this is the first report of carbapenem-resistant Providencia spp. causing infection in a companion animal. This case highlights the emergence of Providencia spp. as potential veterinary pathogens capable of causing severe, invasive and fatal infections. Full article

Kindergarten environments combine high microbial exposure with increased immunological vulnerability, yet antibiotic resistance genes (ARGs) in kindergarten dust remain poorly characterized. This systematic review synthesized evidence on the occurrence and potential health relevance of ARGs in kindergarten dust. Following PRISMA 2020 guidelines, PubMed, Scopus, and Web of Science were searched. Four studies from China, Hong Kong, and Norway (2018–2024) met the inclusion criteria. ARGs were detected in all kindergarten dust samples, indicating that dust is a consistent reservoir of antibiotic resistance determinants. A consensus resistome (classes detected in ≥2 studies) encompassed sulfonamide, macrolide–lincosamide–streptogramin B (MLSB), tetracycline, beta-lactam, aminoglycoside, and multidrug resistance genes; beta-lactam resistance genes were the only class reported in all four studies. Clinically important ARGs associated with last-resort antibiotics, including mecA, vanA, bla_NDM, and mcr-5, were reported in three studies. Class 1 integron-integrase genes (intI1) frequently co-occurred with ARGs, suggesting potential horizontal gene transfer. Limited evidence indicated higher ARG abundance in urban and winter samples. One study reported antibiotic-resistant bacteria carrying resistance markers concordant with those in kindergarten dust in the urine of children attending the same facilities; however, this cross-sectional, single-site evidence is consistent with, but not sufficient to establish, a dust-to-child exposure pathway. The available evidence supports the plausibility that kindergarten dust may contribute to children’s exposure to ARGs and ARG-carrying bacteria, but current studies do not establish causal transmission from dust to child colonization or infection. Standardized monitoring and longitudinal studies are needed to assess health risks and guide mitigation strategies in early childhood educational settings. Full article

Antimicrobial resistance (AMR) is a major One Health challenge driven by antimicrobial misuse in human medicine, veterinary practice, animal production, and polluted environments. Migratory birds move among wetlands, farms, wastewater-affected habitats, landfills, and coastal ecosystems and may acquire and redistribute antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) across ecological and political boundaries. This perspective synthesizes evidence on exposure sources, bacterial reservoirs, resistance determinants, cross-species interfaces, and surveillance priorities while explicitly distinguishing four claims: detection or carriage, persistence in individual birds, redistribution along migratory routes, and onward transmission to recipient hosts or environments. Published studies report multidrug-resistant Escherichia coli, Klebsiella pneumoniae, Salmonella spp., Enterococcus spp., and Campylobacter spp., with determinants including blaCTX-M, blaTEM, blaNDM, mcr, tet, sul, and qnr genes. The eight evidence groups summarized here constitute an illustrative, non-comprehensive selection; they are predominantly observational surveys or screenings, and none reconstructs a complete source–bird–destination–recipient transmission chain. Taxon-specific ecology modifies exposure: gulls and storks frequently exploit refuse and wastewater, waterfowl and shorebirds connect aquatic habitats, whereas passerines often reflect more local point-source contamination. Current evidence therefore supports migratory birds primarily as mobile sentinels and opportunistic carriers of anthropogenic AMR, while acknowledging possible natural or ancestral resistance in avian-associated microbiota. Future surveillance should combine longitudinal sampling, baseline cohorts such as pre-migratory nestlings, paired bird–water–soil–sediment sampling, whole-genome sequencing, plasmid profiling, telemetry, environmental DNA, wastewater-based epidemiology, and interoperable veterinary reporting. Practical mitigation requires antimicrobial stewardship, wastewater and landfill control, farm biosecurity, and coordinated veterinary, environmental, and public-health action. Full article

Background: The spread of extended-spectrum β-lactamase-producing Klebsiella is an emerging public health concern presenting severe clinical impacts. This problem is particularly severe in developing countries where irrational use of antibiotics makes the treatment of such infections more challenging. Methods: In this cross-sectional study, we investigated antibiotic resistance among clinical Klebsiella pneumoniae isolates from 256 patient specimens from Al-Diwaniyah hospitals, using standard microbiological methods followed by PCR. Antimicrobial susceptibility testing identified resistance rates and proportions of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. Carbapenemase genes were detected by multiplex PCR and sequencing. Mutations were characterized, and their functional significance was predicted using in silico prediction tools. Results: Fifty Klebsiella pneumoniae isolates were recovered, exhibiting high resistance rates (42–100%) to penicillins, cephalosporins, fluoroquinolones and carbapenems, with 62% classified as MDR and 38% as XDR. Carbapenemase genes were highly prevalent (blaOXA-48 56%, blaIMP 44%, blaVIM 30%, blaKPC 28%, blaNDM 26%), with 60% of isolates co-harbouring ≥ two genes. Most mutations were predicted to be structurally tolerated, while active-site-proximal substitutions (H120L in NDM-52 and V120L in OXA-48) were predicted to affect enzyme activity. However, docking analysis suggested no significant alteration in carbapenem binding affinity. Conclusions: Our results highlight a very high prevalence of MDR/XDR Klebsiella pneumoniae, associated with diverse carbapenemase genes and resistance-related polymorphisms that may indicate potential functional impacts. To the best of our knowledge, this is the first study in Iraq to combine carbapenemase gene mutation analysis with structural modelling and molecular docking. This study emphasizes the urgent need for effective antimicrobial resistance surveillance in Iraq. Full article

Background: Aztreonam–avibactam (ATM-AVI) is an important therapeutic option for infections caused by metallo-β-lactamase-producing Enterobacterales. However, the emergence of resistance may limit its clinical effectiveness. Here, we report two high-level ATM-AVI-resistant Escherichia coli isolates recovered from critically ill patients in a tertiary hospital in Guangzhou, both of whom had prior exposure to broad-spectrum antimicrobial agents. Methods: Antimicrobial susceptibility testing was performed by broth microdilution. Whole-genome sequencing (WGS) was conducted using the Illumina NovaSeq and Oxford Nanopore Technologies platforms for hybrid assembly. Resistome analysis, multilocus sequence typing (MLST), plasmid replicon typing, and phylogenomic analysis were performed. Comparative genomics with global ST410 isolates was used to investigate the evolutionary origin. Results: Antimicrobial susceptibility testing revealed high-level resistance to ATM-AVI. Hybrid whole-genome sequencing showed that both isolates belonged to the globally disseminated high-risk ST410 lineage and carried bla_NDM-5, CTX-M-type extended-spectrum β-lactamase genes, and an identical four-amino-acid insertion in penicillin-binding protein 3 (ftsI_I334IYRIK). Both isolates exhibited highly conserved chromosomal backbones, differed by only 29 core-genome single-nucleotide polymorphisms, and clustered within a China-associated ST410 clade. Notably, their key resistance determinants were located on distinct plasmid backgrounds: bla_NDM-5 was found on a predicted conjugative IncFIB/IncFIC plasmid in one isolate and on an IncX1 element with potential mobilization in the other. Conclusions: These findings provide important clinical evidence of high-level ATM-AVI resistance in Escherichia coli ST410 isolates in China and highlight the emergence of ATM-AVI resistance-associated determinants within a high-risk genomic background. Active phenotypic and genomic surveillance is warranted as ATM-AVI enters broader clinical use. Full article

Background: Carbapenem-resistant Enterobacterales (CRE) are a major therapeutic challenge, particularly in settings where metallo-β-lactamases are prevalent. Aztreonam–avibactam (AZA) may provide activity against metallo-β-lactamase-producing isolates, whereas ceftazidime–avibactam (CZA) has limited activity against the isolates that harbor these enzymes. This study aimed to evaluate the in vitro activity of aztreonam–avibactam and ceftazidime–avibactam against invasive carbapenem-resistant Enterobacterales isolates and to characterize the distribution of carbapenemase genes in a tertiary-care center in Türkiye. Methods: A total of 100 non-duplicate CRE isolates recovered from blood cultures and sterile body fluids between January 2024 and January 2026 were included. Species identification and routine antimicrobial susceptibility testing were performed using MALDI-TOF MS and an automated system. CZA and AZA MICs were determined by gradient diffusion testing, whereas CZA–aztreonam synergy was assessed separately using a disk/gradient diffusion-based method. Carbapenemase genes were detected by real-time PCR. Whole-genome sequencing was performed for the two AZA-resistant Escherichia coli isolates. Results: The isolate collection was dominated by Klebsiella pneumoniae (87.0%), and most isolates were recovered from blood cultures (80.0%). CZA susceptibility was observed in 31.0% of isolates, with MIC_50/90 values of 256/256 mg/L. In contrast, AZA showed high in vitro activity, with 98.0% of isolates categorized as susceptible and MIC_50/90 values of 0.25/0.50 mg/L. CZA–aztreonam synergy was detected in 98.0% of isolates. Qualitative CZA–aztreonam synergy testing did not fully concord with direct AZA MIC-based susceptibility categorization: one AZA-resistant isolate showed a positive synergy result, whereas one synergy-negative isolate remained AZA-susceptible. Carbapenemase genes were detected in 99.0% of isolates; bla_NDM was the most frequent gene (81.0%), followed by bla_OXA-48 (72.0%), bla_KPC (14.0%), and bla_VIM (4.0%). The most common carbapenemase profile was bla_NDM + bla_OXA-48 (62.0%). bla_NDM carriage was strongly associated with CZA resistance, and CZA MICs were significantly higher among bla_NDM-positive isolates. The two AZA-resistant E. coli isolates belonged to ST500 and ST410, and both carried a YRIK insertion in PBP3; one of them additionally showed ompF disruption associated with a 4 bp insertion. Conclusions: AZA demonstrated potent in vitro activity against invasive CRE isolates in this setting, whereas CZA activity was substantially limited, likely reflecting the high prevalence of bla_NDM and frequent carbapenemase co-carriage. These findings support the potential value of AZA in regions with emerging metallo-β-lactamase predominance and highlight the importance of local molecular surveillance to guide antimicrobial strategies. Full article

Background: Acinetobacter baumannii is an important opportunistic pathogen responsible for healthcare-associated infections, particularly among critically ill, intensive care unit (ICU), and post-surgical patients. The emergence of carbapenem-resistant A. baumannii (CRAB) has become a major therapeutic challenge worldwide because of its multidrug-resistant nature and limited treatment options. Despite the increasing prevalence of CRAB in Pakistan, information regarding the molecular characterization of carbapenem resistance genes among isolates recovered from surgical site infections (SSIs) remains limited. Methods: A cross-sectional study was conducted from November 2023 to February 2024 at Khalifa Gul Nawaz Hospital, Bannu, Khyber Pakhtunkhwa, Pakistan. A total of (n = 118) surgical wound specimens were collected from patients with clinically diagnosed SSIs. A. baumannii isolates were identified using standard biochemical tests and confirmed by 16S rRNA gene sequencing. In vitro antimicrobial susceptibility was determined by Kirby–Bauer disk diffusion according to CLSI 2024 guidelines. In addition, the concentration-dependent inhibition-zone response of imipenem and meropenem against carbapenem-resistant isolates was evaluated using an agar well diffusion assay. Molecular detection of blaNDM-1 and blaOXA-23 was performed by polymerase chain reaction (PCR), and representative amplicons were subjected to Sanger sequencing for further analysis. Results: In the current study, the total number of (n = 118) wound specimens from healthcare-associated patients were processed, in which A. baumannii-positive isolates (n = 23, 19.5%) were documented. Its prevalence was higher in males (69.6%) compared to females, and was strongly associated (78.2%) with elderly patients (aged 51–68 years). In vitro susceptibility testing revealed that 91.3% of isolates harbored multidrug-resistant (MDR) attributes. Antimicrobial susceptibility profiling revealed high levels of multidrug resistance, with 82.6% of isolates resistant to imipenem and meropenem, as well as 100% resistance to aztreonam and gentamicin. Colistin showed the highest activity, with 87.0% of isolates remaining susceptible. In the agar well diffusion assay, measurable inhibition of the carbapenem-resistant isolates by imipenem and meropenem occurred only at higher concentrations. Molecular screening of resistance genes identified blaOXA-23 in 60.9% and blaNDM-1 in 30.4% of isolates. Co-expression of both genes was detected in some (n = 4) isolates. Among the selected MDR isolates included in the gene resistance analysis, imipenem and meropenem resistance were recorded in 9/14 blaOXA-23-positive isolates and 5/7 blaNDM-1-positive isolates. Conclusions: This study substantiates an escalated incidence of carbapenem-resistant, MDR A. baumannii in post-surgical infections. blaOXA-23 were documented as the predominant carbapenemase gene, with co-expression of blaNDM-1 in a substantial proportion of isolates. These findings provide an important phenotypic and molecular characterization of selected carbapenemase genes in healthcare-associated infections, highlighting the exigency for strengthened antimicrobial stewardship and infection control strategies in the hospitals of the region. Full article

Background/Objectives: Klebsiella pneumoniae complex, Escherichia coli, and Enterobacter cloacae complex are considered the most prevalent carbapenemase-producing (CP) Enterobacterales in Spain. However, temporal changes in carbapenemase distribution, clonal diversity, and the mobile genetic elements (MGEs) involved in their dissemination have not been systematically characterised in our region. To address this knowledge gap, this study investigated the epidemiology of these organisms over a seven-year period. Methods: CP Enterobacterales isolates recovered between 2019 and 2025 from rectal screening swabs and clinical specimens (blood, urine, respiratory, wound, and sterile fluid samples) were included. All 297 isolates underwent phenotypic characterisation. Carbapenemase detection and sequence type (ST) assignment were performed for the 282 isolates available for molecular analysis. Following the gradual implementation of long-read whole-genome sequencing (WGS) beginning in 2022, MGEs associated with carbapenemase dissemination were characterised, and selected high-risk clones were analysed by SNP-based phylogenetic analysis. Results: Fifty isolates were recovered from ICU admission rectal screening, and 247 from clinical samples. Although the proportion of CP Enterobacterales among Enterobacterales isolates remained stable throughout the study period, significant changes were observed between 2019 and 2022 and between 2023 and 2025 in carbapenemase types, with a statistically significant increase in metallo-β-lactamases (MBLs) (p < 0.001), as well as in species distribution. Furthermore, predominant plasmid replicons associated with the dissemination of MBL genes were characterised. A K. pneumoniae ST147 clone co-harbouring bla_OXA-48 and bla_NDM-1 emerged and expanded significantly during the study period (p < 0.05). In addition, an ST225 NDM-1 clone was identified. SNP-based phylogenetic analysis revealed distinct genetic clusters within both lineages. Conclusions: Temporal shifts in the epidemiology of CP Enterobacterales, including the emergence and expansion of high-risk clones, were observed. High-resolution genomic analyses provided additional insight into the genetic relationships among circulating lineages. Full article

The dissemination of New Delhi metallo-β-lactamase (NDM)-producing Escherichia coli poses a serious threat to public health. Although increasing attention has been paid to the relationship between temperature and antimicrobial resistance (AMR) transmission, research in China’s Xinjiang region remains scarce. In this study, we conducted a cross-sectional survey of 1914 samples from intensive livestock farms across Xinjiang to characterize the detection rate and antimicrobial resistance profiles of bla_NDM-positive E. coli. Using selective culture, PCR, and 16S rRNA sequencing, we identified 140 bla_NDM-positive E. coli (7.3%), predominantly in northern Xinjiang. The highest detection rate of bla_NDM-positive E. coli was found in Tacheng Prefecture (24.0%), followed by Changji Hui Autonomous Prefecture (4.3%) and Bortala Mongol Autonomous Prefecture (0.6%). No bla_NDM-positive E. coli isolates were detected in Bayingolin Mongol Autonomous Prefecture, Kashgar Prefecture, or from pigeon samples. Binomial logistic regression analysis revealed a significant positive association between regional temperature and the detection rate of bla_NDM-positive E. coli. Genotypic analysis identified 35 distinct resistance gene profiles, with predominant resistance genes including bla_TEM (87.9%), ant(3″)-Ia (97.1%), qnrS (92.9%), tet(A) (95.0%), sul1 (70.0%), sul3 (85.0%), and floR (97.1%); mcr-1 and mcr-8 were not detected. Antibiotic susceptibility tests showed that all isolates were resistant to imipenem and exhibited universal resistance to ampicillin, ceftiofur, tetracycline, florfenicol, and enrofloxacin, whereas the majority remained susceptible to amikacin (99.3%), tigecycline (94.3%), and polymyxin (77.1%). These findings indicate that livestock farms, particularly laying-hen systems in northern Xinjiang, may serve as reservoirs of multidrug-resistant bla_NDM-positive E. coli, and that elevated regional temperature is an environmental factor associated with higher detection rates, underscoring a potential climate-associated risk for the spread of AMR. Full article

Multidrug-resistant (MDR) Klebsiella pneumoniae represents a major clinical and public health challenge worldwide, particularly in regions with limited genomic surveillance. This study investigated the clinical, phenotypic, and genomic characteristics of clinical K. pneumoniae isolates recovered from a tertiary-care hospital in Peshawar, Pakistan. A total of 2400 non-duplicate clinical specimens were processed, and antimicrobial susceptibility testing was performed according to CLSI guidelines. Whole-genome sequencing (WGS) was conducted on a purposively selected subset of 18 isolates representing diverse resistance and phenotypic profiles. Genomic analyses included multilocus sequence typing, resistome and virulome profiling, identification of resistance-associated chromosomal mutations, plasmid replicon typing, and phylogenomic comparison with publicly available international genomes. K. pneumoniae was identified in 256/2400 (10.7%) specimens, predominantly from urine samples. MDR and extensively drug-resistant (XDR) phenotypes were detected in 83.2% and 13.3% of isolates, respectively. WGS revealed substantial genomic heterogeneity, with ST147 identified as the most frequent lineage among sequenced isolates. Extended-spectrum β-lactamase genes, particularly bla_CTX-M-15, together with carbapenemase genes including bla_OXA-48-like and bla_NDM-5, were identified in multiple isolates alongside resistance-associated chromosomal alterations in gyrA, parC, ompK36, mgrB, pmrB, and ramR. Yersiniabactin-associated loci were detected in all sequenced isolates, whereas canonical hypervirulence-associated determinants (rmpA, iuc, iro) were absent. These findings highlight the complex genomic landscape of MDR K. pneumoniae in Pakistan and underscore the need for continued genomic surveillance and antimicrobial stewardship. Full article

The emergence of New Delhi metallo-β-lactamase (NDM)-producing Escherichia coli (E. coli) in the food production chain poses a serious public health threat. This study aimed to investigate the prevalence and molecular characteristics of blaNDM-carrying E. coli along the chicken production chain (farms, slaughterhouses, and supermarkets) in Jiangsu Province, China. Between 2023 and 2025, 408 samples were collected, recovering 39 blaNDM-positive E. coli isolates (9.56%). Isolation rates were 10.4% (26/250) in farms, 10.1% (11/108) in slaughterhouses, and 4.0% (2/50) in supermarkets. Whole-genome sequencing (WGS) identified blaNDM-5 as the dominant variant, alongside the first detection of blaNDM-13 in local farm environments. All isolates exhibited high-level resistance to meropenem (MIC: 16–128 μg/mL) and universal resistance (100%) to ampicillin, cefoxitin, ceftiofur, and sulfisoxazole. Notably, 41.03% and 7.69% of strains co-harbored the polymyxin resistance gene mcr-1.1 and the tigecycline resistance gene tet(X4), respectively. Isolates carried an average of 19.5 antimicrobial resistance genes, with IncFIB (AP001918) (82.05%) identified as the dominant plasmid replicon. Multilocus sequence typing (MLST) revealed 18 distinct sequence types (STs), with ST156 and ST155 being the most prevalent. Phylogenetic analysis confirmed slaughterhouses as critical hubs for cross-contamination, evidenced by shared STs (ST1158, ST155, ST162) and minimal SNP differences (1–11) between environment and carcass isolates. Furthermore, the detection of clinically relevant ST10 and ST69 clones in supermarket retail chicken meat underscores a direct foodborne transmission risk to humans. These findings highlight the poultry supply chain as a significant reservoir of multidrug-resistant blaNDM-positive E. coli. Accordingly, we recommend enhanced biosecurity protocols and stricter restrictions and controls on antimicrobial use in broiler farms. Full article

Vibrio fluvialis is an important zoonotic pathogen that poses a growing threat to both public health and aquaculture, particularly to shrimp and fish farming. In this study, we report that a seafood-associated V. fluvialis strain, 10M-VF, possesses two genomic islands, SGI1-VfNDM1 and GIflu-1, in addition to hemolysins and type VI secretion systems (T6SSs). SGI1-VfNDM1 is a new member of the Salmonella genomic island 1 (SGI1) and harbors several antibiotic resistance genes. A potential transferable region, ISCR1-trpF-ble_MBL-bla_NDM-1, was observed in SGI1-VfNDM1, suggesting that ISCR1 may have mediated the integration of bla_NDM-1 into this island. Additionally, GIflu-1 represents a novel resistance island. Other GIflu variants carrying resistance genes in Vibrio all possess ISCR2, but their resistance regions vary. This indicates that ISCR2 may contribute to the integration of antibiotic resistance genes into GIflu islands. Notably, not every GIflu variant carries drug resistance genes. To the best of our knowledge, GIflu-1 is a previously unreported resistance island, and no previous report has documented the co-existence of two distinct resistance genomic islands in a single Vibrio isolate. The emergence of such resistance islands in a seafood-borne pathogen raises concerns for the maintenance and potential dissemination of clinically important resistance genes in aquatic food systems and underscores the need for ongoing surveillance of resistance determinants in seafood-borne Vibrio populations from a One Health perspective. Full article