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

The study describes an outbreak of Enterobacterales (CPE) in a pediatric ward at a Tokyo academic medical center. The outbreak began with a 1-year-old boy with Klebsiella variicola in June 2016 and Klebsiella quasipneumoniae in March 2017. The spread continued, leading to the declaration of an outbreak in April 2017. The study found CPE surveillance cultures in 19 patients and 9 sinks in the ward, with no positive specimens in uninhabited rooms. All CPE strains analyzed harbored blaIMP-1, except for one with blaIMP-11. CPE was detected even after sink replacement, and infection-control measures focused on sinks were implemented. The study concludes that multiple bacterial species can become CPE via blaIMP-1-carrying IncM1 plasmids and spread through sinks in a hospital ward.