The outbreak of multispecies carbapenemase-producing Enterobacterales associated with pediatric ward sinks: IncM1 plasmids act as vehicles for cross-species transmission

Mayumi Tsukada; Taito Miyazaki; Kotaro Aoki; Sadako Yoshizawa; Yoko Kondo; Tomoka Sawa; Hinako Murakami; Emi Sato; Manabu Tomida; Mariko Otani; Eri Kumade; Emi Takamori; Masako Kambe; Yoshikazu Ishii; Kazuhiro Tateda

doi:10.1016/j.ajic.2024.02.013

The outbreak of multispecies carbapenemase-producing Enterobacterales associated with pediatric ward sinks: IncM1 plasmids act as vehicles for cross-species transmission

Am J Infect Control. 2024 Mar 21:S0196-6553(24)00101-9. doi: 10.1016/j.ajic.2024.02.013. Online ahead of print.

Authors

Affiliations

¹ Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan.
² Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan; Department of General Medicine and Emergency Care, Toho University School of Medicine, Tokyo, Japan.
³ Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo, Japan.
⁴ Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo, Japan; Department of Clinical Laboratory, Toho University Omori Medical Center, Tokyo, Japan. Electronic address: sadako@med.toho-u.ac.jp.
⁵ Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan; Department of Pediatrics, Toho University School of Medicine, Tokyo, Japan.
⁶ Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan; Department of Clinical Laboratory, Toho University Omori Medical Center, Tokyo, Japan.
⁷ Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan; Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo, Japan.
⁸ Department of Infection Prevention and Control, Toho University Omori Medical Center, Tokyo, Japan; Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo, Japan; Department of Clinical Laboratory, Toho University Omori Medical Center, Tokyo, Japan.

PMID: 38613526
DOI: 10.1016/j.ajic.2024.02.013

Abstract

Background: This study describes an outbreak caused by multispecies carbapenemase-producing Enterobacterales (CPE) occurring in a pediatric ward at an academic medical center in Tokyo.

Methods: The index case involved a 1-year-old boy with Klebsiella variicola (CPE) detected in anal swabs in June 2016. The second case was Klebsiella quasipneumoniae (CPE) occurred in March 2017 followed by further spread, leading to the declaration of an outbreak in April 2017. Extensive environmental and patient microbiological sampling was performed. The relatedness of the isolates was determined using draft-whole-genome sequencing.

Results: CPE surveillance cultures of patients and environments were positive in 19 patients and 9 sinks in the ward. The sinks in hospital rooms uninhabited by CPE patients exhibited no positive CPE-positive specimen during the outbreak. All CPE strains analyzed using draft-whole-genome sequencing harbored bla_IMP-1, except for one harboring bla_IMP-11; these strains harbored identical bla_IMP-1-carrying IncM1 plasmids. CPE was detected even after sink replacement; infection-control measures focused on sinks were implemented and the CPE outbreak ended after 7 months.

Conclusions: Multiple bacterial species can become CPE via bla_IMP-1-carrying IncM1 plasmids of the same origin and spread through sinks in a hospital ward. Thorough infection-control measures implemented as a bundle might be crucial.

Keywords: Draft-whole-genome sequencing; Infection-control bundle; Plasmid.