title: Tracking a hospital outbreak of KPC-producing ST11 Klebsiella pneumoniae with whole genome sequencing.
abstract: An outbreak of carbapenem-resistant Klebsiella pneumoniae strains emerged at a hospital, and was tracked in order to understand the spread of these infectious pathogens. A total of 66 K. pneumoniae strains were collected from sterile samples in 2012. The MICs of 20 antimicrobial agents were determined for all strains. Molecular typing was performed with pulsed-field gel electrophoresis (PFGE). Twelve blaKPC-producing K. pneumoniae strains isolated from ten patients were selected for whole genome sequencing. Phylogenetic reconstruction of these 12 strains was performed by the use of single-nucleotide polymorphism (SNP) row sequences of each draft genome sequence. Plasmids from the 12 strains were separated by S1 digestion and PFGE. The 12 K. pneumoniae strains isolated from the ten patients were deemed to be representative of the hospital outbreak, owing to their similar PFGE patterns. These 12 blaKPC-producing strains conferred multidrug resistance, which contrasted with the remaining 54, more susceptible, strains in the hospital. Differences in SNPs between each draft genome of the blaKPC-producing strains partitioned the 12 outbreak strains into three separate clades. The patients with each clade shared close hospital units. All 12 strains harboured at least one multidrug resistance plasmid. Strains showing high-level resistance may facilitate nosocomial dissemination and result in an infectious pathogen outbreak. Although the 12 blaKPC-producing K. pneumoniae strains possessed similar PFGE patterns, SNP variations throughout the genome allowed the strains to be divided into three clades. These results suggest that three independent transmission events led to hospital-wide dissemination of the outbreak strains.
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Disease, First Affiliated Hospital, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Wei
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: X
authors.initials: X
authors.lastname: Hua
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Hangzhou, Zhejiang, China; Translational Medicine Centre, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Hangzhou, Zhejiang, China; State Key Laboratory for Diagnosis and Treatment of Infectious Disease, First Affiliated Hospital, College of Medicine, Hangzhou, Zhejiang, China. Electronic address: yvys119@163.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Yu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D014644:Genetic Variation; D016680:Genome, Bacterial; D005838:Genotype; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058889:Molecular Typing; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA / Q000379:methods*; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: Carbapenem resistance; SNP; outbreak; plasmid; whole genome sequencing