Outbreak of IncX8 Plasmid–Mediated KPC-3–Producing Enterobacterales Infection, China

• Published in: Emerging infectious diseases Vol. 28; no. 7; pp. 1421 - 1430
• Main Authors: Chen, Lan, Ai, Wenxiu, Zhou, Ying, Wu, Chunyang, Guo, Yinjuan, Wu, Xiaocui, Wang, Bingjie, Rao, Lulin, Xu, Yanlei, Zhang, Jiao, Chen, Liang, Yu, Fangyou
• Format: Journal Article
• Language: English
• Published: Atlanta U.S. National Center for Infectious Diseases 01.07.2022; Centers for Disease Control and Prevention
• Subjects: Antibiotics; Antimicrobial agents; Buildings; carbapenemase; Cardiovascular disease; Causes of; China; Cloning; E coli; Enterobacterales; Epidemics; Genetic aspects; Genomes; Gram-negative bacteria; Gram-negative bacterial infections; horizontal transfer; Hospitals; Identification and classification; Infections; Klebsiella pneumoniae; KPC-3; Medical equipment; Outbreaks; Pathogens; Patients; Plasmids; Public health; Statistics; Surgery; transmission; Whole genome sequencing; China
• ISSN: 1080-6040; 1080-6059; 1080-6059
• DOI: 10.3201/eid2807.212181

Carbapenem-resistant Enterobacterales (CRE) infection is highly endemic in China; Klebsiella pneumoniae carbapenemase (KPC) 2–producing CRE is the most common, whereas KPC-3–producing CRE is rare. We report an outbreak of KPC-3–producing Enterobacterales infection in China. During August 2020–June 2021, 25 blaKPC-3–positive Enterobacteriale isolates were detected from 24 patients in China. Whole-genome sequencing analysis revealed that the blaKPC-3 genes were harbored by IncX8 plasmids. The outbreak involved clonal expansion of KPC-3–producing Serratia marcescens and transmission of blaKPC-3 plasmids across different species. The blaKPC-3 plasmids demonstrated high conjugation frequencies (10−3 to 10−4). A Galleria mellonella infection model showed that 2 sequence type 65 K2 K. pneumoniae strains containing blaKPC-3 plasmids were highly virulent. A ceftazidime/avibactam in vitro selection assay indicated that the KPC-3–producing strains can readily develop resistance. The spread of blaKPC-3–harboring IncX8 plasmids and these KPC-3 strains should be closely monitored in China and globally.