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Background: Urinary tract infection (UTI) associated with Klebsiella pneumoniae poses a serious threat for inpatients. This study aimed to describe the genomic characteristics of K. pneumoniae causing UTI in a tertiary-care hospital in Beijing, China. Methods: A total of 20 K. pneumoniae strains collected from 2020 to 2021 were performed whole-genome sequencing. The Antibiotic susceptibility of 19 common antimicrobial agents was tested against all strains. The multi-locus sequence types (MLSTs) and serotypes were determined from the WGS data. De novo assemblies were used to identify resistance and virulence genes. The presence and characteristics of the plasmids were detected using hybrid assembly of long and short-read data. Results: These K. pneumoniae strains were clustered into nine sequence types (STs) and twelve K-serotypes. All the carbapenem-resistant K. pneumoniae (CRKP) strains acquired carbapenemase blaKPC-2 (n=7). Two CRKP strains exhibited increased resistance to Polymyxin B with MIC ≥ 4 mg/L due to insertion of an IS5-like sequence in the mgrB gene, and they were also involved in a transmission event in Intensive Care Unit. Long-read assemblies identified many plasmids co-carrying multiple replicons. Acquisition of a new IncM2_1 type blaCTX-M-3 positive plasmid was observed after transfer from ICU to neurovascular surgery by comparing the two strains collected from the same patient. Conclusion: K. pneumoniae is a significant pathogen responsible for urinary tract infections. The ST11-KL47 strain, prevalent at our hospital, exhibits a combination of high drug resistance and hypervirulence. It is imperative to enhance ongoing genomic surveillance of urinary tract infection-causing pathogens. [ABSTRACT FROM AUTHOR]

Human astroviruses (HAstV) are etiologic agents of acute gastroenteritis that most often afflict young children and elderly adults. Most studies of HAstV have focused on epidemiology. In this study, we collected 10 stool samples from a diarrhea outbreak from a diarrhea sentinel surveillance hospital in Beijing. Samples were evaluated immediately using parallel multiplex RT-qPCR and nanopore sequencing, and were then amplified by designed primers and Sanger sequencing to obtain whole genome sequences. Six isolates were categorized as HAstV-5 and subjected to whole genome analysis to characterize their genetic variation and evolution. Full genome analysis revealed low genetic variation (99.38–100% identity) among isolates. Phylogenetic analysis showed that all isolates were closely related to domestic strains Yu/1-CHN and 2013/Fuzhou/85. The recombination breakpoint of the six isolates was located at 2741 bp in the overlap region of ORF1a and ORF1b, similar to those of Yu/1-CHN and 2013/Fuzhou/85. Overall, our study highlights the combined use of RT-qPCR and sequencing as an important tool in rapid diagnosis and acquisition of whole genome sequences of HAstV. Highlights: We parallel used multiplex RT-PCR and nanopore sequencing to identify Human astroviruse from 10 stool samples of a diarrhea outbreak from a diarrhea sentinel surveillance hospital in this study. Six isolates were categorized as HAstV-5 and subjected to whole genome analysis to characterize their genetic variation and evolution.It is showed that the combined use of RT-PCR and sequencing as an important tool in rapid diagnosis and acquisition of whole genome sequences of HAstV. [ABSTRACT FROM AUTHOR]

aimed to study the phenotypic and genotypic characteristics of carbapenem-resistant K. pneumoniae (CRKP) isolates from a hospital in Beijing. Methods: Twenty-four CRKP clinical isolates were collected within a half-year to investigate antimicrobial resistance and genomic characteristics. Illumina and Nanopore sequencing were performed to assemble and annotate genomes. Results: All strains were multi-drug resistant. Twenty-two strains carried the blaKPC-2 gene and two harbored blaNDM-5. Multilocus sequence type(MLST) analysis identified five sequence types; most isolates belonged to ST11. Three strains were isolated from the same patient; each carried a different plasmid replicon, either IncFII (pHN7A8), IncX, or IncFIB (K). Conclusion: This study furthers the understanding of CRKP antimicrobial resistance genotypes, and may facilitate the control of nosocomial infections caused by antimicrobial-resistant pathogens. [ABSTRACT FROM AUTHOR]

The spread of carbapenem-resistant Klebsiella pneumoniae has become a significant problem for public health in recent years. In this study, we reported a New Delhi metallo-β-lactamase 1 (NDM-1)-producing K. pneumoniae strain KP14003 from a neonate in Beijing, China. Whole-genome sequencing was performed. The strain belonged to sequence type ST719. Coexistence of blaNDM-1 and blaSHV-12 was found on a self-transferable plasmid, which had a typical IncX3 backbone. The horizontal transfer of blaNDM-1 was associated with Tn125 followed by possible transposition events. Other class A extended-spectrum β-lactamase genes (blaSHV-27 and blaTEM-1) were also identified on chromosome or plasmid. The dissemination of NDM-1-producing K. pneumoniae causes great challenges to the treatment of clinical infections. Effective actions need to be taken to control the further spread of this pathogen. [ABSTRACT FROM AUTHOR]