Characterization of carbapenem-resistant Serratia marcescens harboring blaGES-5 isolated from an outbreak, Japan

Serratia marcescens is a major opportunistic pathogen caused nosocomial infections with a significant impact on morbility and mortality. The infections caused by carbapenem-resistant S. marcescens strains in the nosocomial environment impair therapy and limit treatment options. GES-type beta-lactamases, which belonging to amber class A beta-lactamases, confer beta-lactam resistance, several GES-type enzyme variants including GES-5 have exhibits carbapenemase activity. GES-5 producing Enterobacterales was recently disseminated in clinical cases and occurred outbreaks in hospital in some countries. In Japan, the first outbreak of P. aeruginosa harboring blaGES-5 gene was occurred in 2014. Here, we describe the genetic characteristics regarding antimicrobial resistance of GES-5 producing S. marcescens isolated from the outbreak in intensive care units in 2020. Our study was approved by the Ethics Committee of Kobe Institute of health.