[Importance and prevalence of multidrug-resistant gram-negative bacteria in Germany]. / Gramnegative Erreger (3MRGN/4MRGN): Häufigkeit und Besonderheiten.

Infections with multidrug-resistant gram-negative bacterial species are a great concern in clinics in Germany. By limiting therapeutic options dramatically, these bacteria pose a significant threat to patient health and cause extensive pressure on hygiene systems and patient management. In Germany, the recommendations on how to deal with these bacteria are called MRGN classification, using the terms 3MRGN and 4MRGN for bacteria resistant to three or four major classes of antibiotics. To be resistant to this large number of antibiotics and become classified as 3MRGN or 4MRGN, bacterial strains need to acquire multiple resistance mechanisms with beta-lactamases, especially carbapenemases, being the most important ones. According to established surveillance systems like national reporting systems, KISS or the National Reference Centre, multidrug-resistant bacteria are constantly on the rise in Germany. Although several novel therapeutic options have been approved recently, these bacteria represent a constant challenge and it may be necessary to discuss if the present hygiene recommendations need an update for an efficient and targeted prevention of transmission.

[Multi-resistant pathogens - are they also resistant to disinfectants?] / Multiresistente Erreger ­ Sind sie auch resistent gegenüber Desinfektionsmitteln?

Epidemiological studies show that the care of patients in rooms with a previous stay by a person with evidence of multi-resistant pathogens (MRP) is associated with an increased risk of these pathogens occurring. The question therefore regularly arises as to whether MRP also exhibit resistance to the disinfectants used. To date, there are no standardised definitions for "resistance" to disinfectants. However, disinfectants authorised on the market are also effective against multi-resistant pathogens and the failure of efficient disinfection is mainly caused by application errors (insufficient cleaning, incomplete wetting, incorrect application concentration or exposure time etc.). The effectiveness of disinfectants depends on a variety of environmental factors (especially accompanying contamination). A reduced sensitivity to disinfectants can occur in individual isolates due to selection under sub-inhibitory concentrations of disinfectants. Resistance mechanisms to antibiotics do not mediate cross-resistance to disinfectants, but a change in the permeability of bacterial cells can influence sensitivity to disinfectants and antibiotics. In general, the success of routine disinfection can be improved by suitable process controls and contribute to reducing the transmission of MRP.

[Multi-resistant bacteria - epidemiological trends and new treatment options]. / Multiresistente Bakterien ­ epidemiologische Trends und neue Behandlungsoptionen.

Multi-resistant bacteria such as Escherichia coli and Klebsiella pneumoniae are a growing threat worldwide. The spread of Carbapenemase-producing strains is particularly worrying. New antibiotics and combination therapies offer treatment options, but the development of resistant pathogens remains a major challenge.

Genotypic and phenotypic characterisation of asymptomatic bacteriuria (ABU) isolates displaying bacterial interference against multi-drug resistant uropathogenic E. Coli.

Escherichia coli can colonise the urogenital tract of individuals without causing symptoms of infection, in a condition referred to as asymptomatic bacteriuria (ABU). ABU isolates can protect the host against symptomatic urinary tract infections (UTIs) by bacterial interference against uropathogenic E. coli (UPEC). The aim of this study was to investigate the genotypic and phenotypic characteristics of five ABU isolates from midstream urine samples of adults. Comparative genomic and phenotypic analysis was conducted including an antibiotic resistance profile, pangenome analysis, and a putative virulence profile. Based on the genome analysis, the isolates consisted of one from phylogroup A, three from phylogroup B2, and one from phylogroup D. Two of the isolates, PUTS 58 and SK-106-1, were noted for their lack of antibiotic resistance and virulence genes compared to the prototypic ABU strain E. coli 83,972. This study provides insights into the genotypic and phenotypic profiles of uncharacterised ABU isolates, and how relevant fitness and virulence traits can impact their potential suitability for therapeutic bacterial interference.

Proven anti-virulence therapies in combating methicillin- and vancomycin-resistant Staphylococcus aureus infections.

Introduction: Despite years of efforts to develop new antibiotics for eradicating multidrug-resistant (MDR) and multi-virulent Methicillin-Resistant Staphylococcus aureus (MRSA) and Vancomycin-Resistant Staphylococcus aureus (VRSA) infections, treatment failures and poor prognoses in most cases have been common. Therefore, there is an urgent need for new therapeutic approaches targeting virulence arrays. Our aim is to discover new anti-virulence therapies targeting MRSA and VRSA virulence arrays. Methodology: We employed phenotypic, molecular docking, and genetic studies to screen for anti-virulence activities among selected promising compounds: Coumarin, Simvastatin, and Ibuprofen. Results: We found that nearly all detected MRSA and VRSA strains exhibited MDR and multi-virulent profiles. The molecular docking results aligned with the phenotypic and genetic assessments of virulence production. Biofilm and hemolysin productions were inhibited, and all virulence genes were downregulated upon treatment with sub-minimum inhibitory concentration (sub-MIC) of these promising compounds. Ibuprofen was the most active compound, exhibiting the highest inhibition and downregulation of virulence gene products. Moreover, in vivo and histopathological studies confirmed these results. Interestingly, we observed a significant decrease in wound area and improvements in re-epithelialization and tissue organization in the Ibuprofen and antimicrobial treated group compared with the group treated with antimicrobial alone. These findings support the idea that a combination of Ibuprofen and antimicrobial drugs may offer a promising new therapy for MRSA and VRSA infections. Conclusion: We hope that our findings can be implemented in clinical practice to assist physicians in making the most suitable treatment decisions.

Hypermucoviscous Klebsiella Pneumoniae Caused Community-Acquired Pneumonia in Gondar, Northwest Ethiopia.

BACKGROUND: The incidence of hypermucoviscous Klebsiella pneumoniae (hmvKp), which complicates community-acquired pneumonia, has been increasing recently. This study aimed to detect hypermucoviscous K. pneumoniae and determine its antimicrobial susceptibility pattern in adult patients with community-acquired pneumonia in Northwest Ethiopia. METHODS: This cross-sectional study included 39 K. pneumoniae isolates identified by using Gram stain, culture, and biochemical tests from 312 adult patients with community-acquired pneumonia at the University of Gondar Comprehensive Specialized Referral Hospital from April to June 2021. The hypermucoviscous strains were identified by using the string test. Antimicrobial susceptibility testing was performed by using the Kirby-Bauer disk dif-fusion method. Data were entered by using EPI data version 4.6 and were analyzed by using SPSS version 20. A p-value ≤ 0.05 at a 95% confidence interval was considered statistically significant. RESULTS: Overall, 35.9% (n = 14) of the 39 K. pneumoniae isolates were hypermucoviscous phenotype. The mean age of the hmvKp group was lower than of the cKp group (36.93 ± 12.573 vs. 53.52 ± 19.556 years, p = 0.007). All hmvKp isolates were resistant to amoxicillin-clavulanic acid and trimethoprim-sulfamethoxazole. Azithromycin resistance in the hmvKp strains was significantly higher than in the cKp group (p = 0.012). CONCLUSIONS: This study demonstrates that the hmvKp phenotype causes community-acquired pneumonia and a full resistance to amoxicillin-clavulanic acid and trimethoprim-sulfamethoxazole. Antimicrobial resistance was higher in the hmvKp strain than in the classic strains. Further detection of resistance genes, capsular serotypes, hypermucoviscosity-related genes, and virulence genes is necessary.

BWC0977, a broad-spectrum antibacterial clinical candidate to treat multidrug resistant infections.

The global crisis of antimicrobial resistance (AMR) necessitates the development of broad-spectrum antibacterial drugs effective against multi-drug resistant (MDR) pathogens. BWC0977, a Novel Bacterial Topoisomerase Inhibitor (NBTI) selectively inhibits bacterial DNA replication via inhibition of DNA gyrase and topoisomerase IV. BWC0977 exhibited a minimum inhibitory concentration (MIC90) of 0.03-2 µg/mL against a global panel of MDR Gram-negative bacteria including Enterobacterales and non-fermenters, Gram-positive bacteria, anaerobes and biothreat pathogens. BWC0977 retains activity against isolates resistant to fluoroquinolones (FQs), carbapenems and colistin and demonstrates efficacy against multiple pathogens in two rodent species with significantly higher drug levels in the epithelial lining fluid of infected lungs. In healthy volunteers, single-ascending doses of BWC0977 administered intravenously ( https://clinicaltrials.gov/study/NCT05088421 ) was found to be safe, well tolerated (primary endpoint) and achieved dose-proportional exposures (secondary endpoint) consistent with modelled data from preclinical studies. Here, we show that BWC0977 has the potential to treat a range of critical-care infections including MDR bacterial pneumonias.

The genetic relationship between human and pet isolates: a core genome multilocus sequence analysis of multidrug-resistant bacteria.

INTRODUCTION: The global increase of multidrug-resistant organisms (MDROs) is one of the most urgent public health threats affecting both humans and animals. The One Health concept emphasizes the interconnectedness of human, animal and environmental health and highlights the need for integrated approaches to combat antimicrobial resistance (AMR). Although the sharing of environments and antimicrobial agents between companion animals and humans poses a risk for MDRO transmission, companion animals have been studied to a lesser extent than livestock animals. This study therefore used core genome multilocus sequence typing (cgMLST) to investigate the genetic relationships and putative transmission of MDROs between humans and pets. METHODS: This descriptive integrated typing study included 252 human isolates, 53 dog isolates and 10 cat isolates collected from 2019 to 2022 at the Charité University Hospital in Berlin, Germany. CgMLST was performed to characterize methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and multidrug-resistant gram-negative bacteria. The genetic diversity of the MDROs of the different host populations was determined and compared based on sequence type and core genome complex type. RESULTS: Within this study the majority of samples from pets and humans was genetically distinct. However, for some isolates, the number of allelic differences identified by cgMLST was low. Two cases of putative household transmission or shared source of VR E. faecium and MDR E. coli between humans and pets were documented. CONCLUSIONS: The interaction between humans and their pets appears to play a minor role in the spread of the MDROs studied. However, further research is needed. This study emphasizes the importance of comprehensive molecular surveillance and a multidisciplinary One Health approach to understand and contain the spread of MDROs in human and animal populations. TRIAL REGISTRATION: The study is registered with the German Clinical Trials Register (DRKS00030009).

pQEB1: a hospital outbreak plasmid lineage carrying bla KPC-2.

While conducting genomic surveillance of carbapenemase-producing Enterobacteriaceae (CPE) from patient colonisation and clinical infections at Birmingham's Queen Elizabeth Hospital (QE), we identified an N-type plasmid lineage, pQEB1, carrying several antibiotic resistance genes, including the carbapenemase gene bla KPC-2. The pQEB1 lineage is concerning due to its conferral of multidrug resistance, its host range and apparent transmissibility, and its potential for acquiring further resistance genes. Representatives of pQEB1 were found in three sequence types (STs) of Citrobacter freundii, two STs of Enterobacter cloacae, and three species of Klebsiella. Hosts of pQEB1 were isolated from 11 different patients who stayed in various wards throughout the hospital complex over a 13 month period from January 2023 to February 2024. At present, the only representatives of the pQEB1 lineage in GenBank were carried by an Enterobacter hormaechei isolated from a blood sample at the QE in 2016 and a Klebsiella pneumoniae isolated from a urine sample at University Hospitals Coventry and Warwickshire (UHCW) in May 2023. The UHCW patient had been treated at the QE. Long-read whole-genome sequencing was performed on Oxford Nanopore R10.4.1 flow cells, facilitating comparison of complete plasmid sequences. We identified structural variants of pQEB1 and defined the molecular events responsible for them. These have included IS26-mediated inversions and acquisitions of multiple insertion sequences and transposons, including carriers of mercury or arsenic resistance genes. We found that a particular inversion variant of pQEB1 was strongly associated with the QE Liver speciality after appearing in November 2023, but was found in different specialities and wards in January/February 2024. That variant has so far been seen in five different bacterial hosts from six patients, consistent with recent and ongoing inter-host and inter-patient transmission of pQEB1 in this hospital setting.

Surprising diversity of new plasmids in bacteria isolated from hemorrhoid patients.

Background: Hemorrhoids are common conditions at or around the anus, to which numerous people suffer worldwide. Previous research has suggested that microbes may play a role in the development of hemorrhoids, and the origins of these microbes have been preliminarily investigated. However, no detailed research on the microbes related to hemorrhoid patients has been conducted. This work aims to provide an initial investigation into the microbes related to hemorrhoid patients with high quality whole genome sequencing. Methods: Forty-nine bacterial strains were isolated from seven hemorrhoid patients. Third-generation nanopore sequencing was performed to obtain high quality whole genome sequences. The presence of plasmids, particularly new plasmids, along with antibiotic resistance genes, was investigated for these strains. Phylogenetic analysis and genome comparisons were performed. Results: Out of the 31 plasmids found in the strains, 15 new plasmids that have not been observed previously were discovered. Further structural analysis revealed new multidrug-resistant conjugative plasmids, virulent plasmids, and small, high-copy mobile plasmids that may play significant functional roles. These plasmids were found to harbor numerous integrases, transposases, and recombinases, suggesting their ability to quickly obtain genes to change functions. Analysis of antibiotic resistance genes revealed the presence of antibiotic resistant-integrons. Together with the surprising number of new plasmids identified, as well as the finding of transmission and modification events for plasmids in this work, we came to the suggestion that plasmids play a major role in genetic plasticity. Conclusion: This study reveals that the diversity of plasmids in human-associated microbes has been underestimated. With the decreasing cost of whole-genome sequencing, monitoring plasmids deserves increased attention in future surveillance efforts.

Drug resistance and genomic variations among Mycobacterium tuberculosis isolates from The Nile Delta, Egypt.

Tuberculosis is a global public health concern. Earlier reports suggested the emergence of high rates of drug resistant tuberculosis in Egypt. This study included 102 isolates of Mycobacterium tuberculosis collected from two reference laboratories in Cairo and Alexandria. All clinical isolates were sub-cultured on Löwenstein-Jensen medium and analyzed using both BD BACTEC MGIT 960 SIRE Kit and standard diffusion disk assays to identify the antibiotic sensitivity profile. Extracted genomic DNA was subjected to whole genome sequencing (WGS) using Illumina platform. Isolates that belong to lineage 4 represented > 80%, while lineage 3 represented only 11% of the isolates. The percentage of drug resistance for the streptomycin, isoniazid, rifampicin and ethambutol were 31.0, 17.2, 19.5 and 20.7, respectively. Nearly 47.1% of the isolates were sensitive to the four anti-tuberculous drugs, while only one isolate was resistant to all four drugs. In addition, several new and known mutations were identified by WGS. High rates of drug resistance and new mutations were identified in our isolates. Tuberculosis control measures should focus on the spread of mono (S, I, R, E)- and double (S, E)-drug resistant strains present at higher rates throughout the whole Nile Delta, Egypt.

Impact of untreated tannery wastewater in the evolution of multidrug-resistant bacteria in Bangladesh.

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = - 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = - 0.7112, p = 0.0252) and TDS and bacterial load (r = - 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries.

Genomic profiling of pan-drug resistant proteus mirabilis Isolates reveals antimicrobial resistance and virulence gene landscape.

Proteus mirabilis is a gram-negative pathogen that caused significant opportunistic infections. In this study we aimed to identify antimicrobial resistance (AMR) genes and virulence determinants in two pan-drug resistant isolate "Bacteria_11" and "Bacteria_27" using whole genome sequencing. Proteus mirabilis "Bacteria_11" and "Bacteria_27" were isolated from two different hospitalized patients in Egypt. Antimicrobial susceptibility determined using Vitek 2 system, then whole genome sequencing (WGS) using MinION nanopore sequencing was done. Antimicrobial resistant genes and virulence determinants were identified using ResFinder, CADR AMR database, Abricate tool and VF analyzer were used respectively. Multiple sequence alignment was performed using MAFFT and FastTree, respectively. All genes were present within bacterial chromosome and no plasmid was detected. "Bacteria_11" and "Bacteria_27" had sizes of approximately 4,128,657 bp and 4,120,646 bp respectively, with GC content of 39.15% and 39.09%. "Bacteria_11" and "Bacteria_27" harbored 43 and 42 antimicrobial resistance genes respectively with different resistance mechanisms, and up to 55 and 59 virulence genes respectively. Different resistance mechanisms were identified: antibiotic inactivation, antibiotic efflux, antibiotic target replacement, and antibiotic target change. We identified several genes associated with aminoglycoside resistance, sulfonamide resistance. trimethoprim resistance tetracycline resistance proteins. Also, those responsible for chloramphenicol resistance. For beta-lactam resistance, only blaVEB and blaCMY-2 genes were detected. Genome analysis revealed several virulence factors contribution in isolates pathogenicity and bacterial adaptation. As well as numerous typical secretion systems (TSSs) were present in the two isolates, including T6SS and T3SS. Whole genome sequencing of both isolates identify their genetic context of antimicrobial resistant genes and virulence determinants. This genomic analysis offers detailed representation of resistant mechanisms. Also, it clarifies P. mirabilis ability to acquire resistance and highlights the emergence of extensive drug resistant (XDR) and pan-drug resistant (PDR) strains. This may help in choosing the most appropriate antibiotic treatment and limiting broad spectrum antibiotic use.

Biological and genomic characterization of a polyvalent phage PSH-1 against multidrug-resistant Salmonella Enteritidis.

BACKGROUND: Bacteriophage has been renewed attention as a new antibacterial agent due to the limitations of antibiotic treatment. Bacteriophages are generally thought to be highly host specific and even strain specific, but a small number of polyvalent bacteriophages have been found to infect bacteria of different genera. RESULTS: In this study, a virulent lytic bacteriophage (named Salmonella phage PSH-1) of Salmonella Enteritidis was isolated from the sewage samples of a large-scale pig farm, PSH-1 demonstrated lytic activity against four multidrug-resistant Salmonella Enteritidis isolates and Escherichia coli, and then its biological characteristics, genome and bacteriostatic ability were investigated. The results showed that the initial titer of PSH-1 was 1.15 × 1010 PFU/mL and the optimal multiplicity of infection (MOI) was 0.01, PSH-1 has stable activity in the range of pH 3.0-11.0. One-step growth curve showed that its latent period was 20 min, burst time was 80 min, and the burst was 495 particles. The whole-genome sequencing results revealed phage PSH-1 had a linear dsDNA with 48,466 bp length. The G/C content was 45.33%. Non-coding RNA genes and virulence factors were not found. Eighty- five open reading frames (ORFs) were identified after online annotation. By tests, the use of phage could succeed in controlling the artificial Salmonella contamination in milk at a range of temperatures. CONCLUSIONS: This study reports a novel Salmonella Enteritidis phage PSH-1, which has a robust lytic ability, no virulence factors, and good stability. The characterization and genomic analysis of PSH-1 will develop our understanding of phage biology and diversity and provide a potential arsenal for controlling of salmonellosis.

Phenotypic and genotypic perspectives on detection methods for bacterial antimicrobial resistance in a One Health context: research progress and prospects.

The widespread spread of bacterial antimicrobial resistance (AMR) and multidrug-resistant bacteria poses a significant threat to global public health. Traditional methods for detecting bacterial AMR are simple, reproducible, and intuitive, requiring long time incubation and high labor intensity. To quickly identify and detect bacterial AMR is urgent for clinical treatment to reduce mortality rate, and many new methods and technologies were required to be developed. This review summarizes the current phenotypic and genotypic detection methods for bacterial AMR. Phenotypic detection methods mainly include antimicrobial susceptibility tests, while genotypic detection methods have higher sensitivity and specificity and can detect known or even unknown drug resistance genes. However, most of the current tests are either genotypic or phenotypic and rarely combined. Combining the advantages of phenotypic and genotypic methods, combined with the joint application of multiple rapid detection methods may be the trend for future AMR testing. Driven by rapid diagnostic technology, big data analysis, and artificial intelligence, detection methods of bacterial AMR are expected to constantly develop and innovate. Adopting rational detection methods and scientific data analysis can better address the challenges of bacterial AMR and ensure human health and social well-being.

Whole-genome sequencing of two multidrug-resistant acinetobacter baumannii strains isolated from a neonatal intensive care unit in Egypt: a prospective cross-sectional study.

BACKGROUND: Acinetobacter baumannii (A. baumannii) is a life-threatening and challenging pathogen. In addition, it accounts for numerous serious infections, particularly among immunocompromised patients. Resistance to nearly all clinically used antibiotics and their ability to spread this resistance is one of the most important concerns related to this bacterium. OBJECTIVES: This study describes different molecular mechanisms of two multidrug-resistant A. baumannii isolates obtained from endotracheal aspirates collected from the neonatal intensive care unit (NICU), Ain Shams University Hospital, Egypt. METHODS: Following the identification of two isolates, they were examined for susceptibility to antimicrobial agents. This was followed by multilocus sequence typing as well as whole-genome sequence (WGS). Additionally, a Pathosystems Resources Integration Center (PATRIC) analysis was performed. RESULTS: Two isolates, Ab119 and Ab123, exhibited resistance to all tested antibiotics except for tigecycline and colistin. The WGS analysis of antimicrobial resistance genes (AMR) indicated that both isolates shared beta-lactam, aminoglycoside, macrolides, and sulfonamide resistance genes. Furthermore, each strain revealed different resistance genes such as blaNDM-1, blaNDM-10, OXA-64, aph (3')-VI, Tet-B in Ab119 strain and blaOXA-68, blaPER-1, blaPER-7, Tet-39 in Ab123 strain. Multiple efflux pump genes were detected. Multilocus sequence typing indicated that both isolates belong to the same sequence type (ST931), which belongs to international clone (IC3). Both isolates exhibited the presence of multiple mobile genetic elements (MGEs), but no plasmid was detected in either of them. CONCLUSIONS: A low prevalence of the IC3 sequence type was identified among two A. baumannii isolates obtained from the NICU in Egypt, exhibiting a high resistance level. Healthcare workers must have knowledge regarding the prevalence of A. baumannii among different populations in order to administer suitable treatment, improve patient outcomes, and apply effective infection control practices.

Prevalence, antimicrobial resistance and genomic comparison of non-typhoidal salmonella isolated from pig farms with different levels of intensification in Yangon Region, Myanmar.

In Myanmar, where backyard, semi-intensive, and intensive pig (Sus scrofa domesticus) farming coexist, there is limited understanding of the zoonotic risks and antimicrobial resistance (AMR) associated with these farming practices. This study was conducted to investigate the prevalence, AMR and genomic features of Salmonella in pig farms in the Yangon region and the impact of farm intensification to provide evidence to support risk-based future management approaches. Twenty-three farms with different production scales were sampled for two periods with three sampling-visit each. Antimicrobial susceptibility tests and whole-genome sequencing were performed on the isolates. The prevalence of Salmonella was 44.5% in samples collected from backyard farms, followed by intensive (39.5%) and semi-intensive farms (19.5%). The prevalence of multi-drug resistant isolates from intensive farms (45/84, 53.6%) was higher than those from backyard (32/171, 18.7%) and semi-intensive farms (25/161, 15.5%). Among 28 different serovars identified, S. Weltevreden (40; 14.5%), S. Kentucky (38; 13.8%), S. Stanley (35, 12.7%), S. Typhimurium (22; 8.0%) and S. Brancaster (20; 7.3%) were the most prevalent serovars and accounted for 56.3% of the genome sequenced strains. The diversity of Salmonella serovars was highest in semi-intensive and backyard farms (21 and 19 different serovars, respectively). The high prevalence of globally emerging S. Kentucky ST198 was detected on backyard farms. The invasive-infection linked typhoid-toxin gene (cdtB) was found in the backyard farm isolated S. Typhimurium, relatively enriched in virulence and AMR genes, presented an important target for future surveillance. While intensification, in terms of semi-intensive versus backyard production, maybe a mitigator for zoonotic risk through a lower prevalence of Salmonella, intensive production appears to enhance AMR-associated risks. Therefore, it remains crucial to closely monitor the AMR and virulence potential of this pathogen at all scales of production. The results underscored the complex relationship between intensification of animal production and the prevalence, diversity and AMR of Salmonella from pig farms in Myanmar.

Investigating the interaction of zno nanoparticles with flagellum and fimbriae in multi-drug resistant uropathogenic bacteria encoding fli and fim genes.

Due to the increasing occurrence of drug resistant urinary tract infections (UTI) among children, there is a need to investigate alternative effective treatment protocols such as nanoparticles. Flagella and fimbriae are primary factors contributing the virulence of urinary tract infecting bacteria. The aim of this study was to assess the antibacterial effects of zinc oxide nanoparticles which have been synthesized using both chemical and green methods on multi-drug resistant (MDR) uropathogenic bacteria encoding fli and fim genes and investigating their binding ability to bacterial appendage proteins. A total of 30 urine culture samples were collected from children under 2 years old diagnosed with urinary tract infection. The isolates underwent antibiotic suseptibility assessment and the isolates demonstrating MDR were subjected to molecular amplification of fimG (fimbrial) and fliD and fliT (flagellal) genes. The confirmation of cellular appendages was achieved through silver nitrate staining. The antibacterial efficacy of the synthetized nanoparticles was assessed using the micro and macrodilution methods. The successful binding of nanoparticles to bacterial appendage proteins was confirmed through mobility shift and membrane filter assays. The dimensions of chemically synthesized ZnO nanoparticles and green nanoparticles were measured at 30 nm and 85 nm, respectively, with the exhibition of hexagonal geometries. The nanoparticles synthesized through chemical and green methods exhibited minimum inhibitory concentrations (MIC) of 0.0062-0.025 g/L and 0.3 g/L, respectively. The ability of ZnO nanoparticles to bind bacterial appendage proteins and to combat MDR uropathogenic bacteria are promising for new treatment protocols against UTI in children in future.

Sheep and goats as reservoirs of colistin-resistant E. coli: first detection of ETEC ST10 and E. coli ST6396 mcr-1 positive strains in North Africa.

AIM: This study aimed to screen and characterize colistin-resistant strains isolated from different livestock species in Algeria, including sheep, goats, and dromedaries. METHODS AND RESULTS: A total of 197 rectal and nasal swabs were screened for colistin-resistant Gram-negative bacilli. Twenty one isolates were selected, identified, and their antibiotic resistance was phenotypically and genotypically characterized. The majority (15/21) were affiliated to Escherichia coli, from which 4 strains isolated from sheep (n = 2) and goats (n = 2) and belonging to phylogroup A and ST10 and ST6396 lineages, respectively, carried the mcr-1 gene. The remaining isolates were identified as belonging to the following genera: Raoultella, Enterobacter, Klebsiella, and Pseudomonas. CONCLUSION: This study highlights the presence of virulent and multiresistant Gram-negative bacilli in farm animals, increasing the risk of transmitting potentially fatal infections to humans.