Emergence of high-risk ST595 and ST640 clones of carbapenem-resistant Serratia marcescens: insights from genomic and virulence profiling during a nosocomial epidemic

This study provides the first integrated genomic and phenotypic characterization of CRSM during a documented hospital outbreak, highlighting ST595 and ST640 as high-risk clones with distinct virulence signatures. The convergence of rapid growth, biofilm capacity, and serum resistance in select isolates underscores their potential role in prolonged colonization and nosocomial spread. These findings emphasize the urgent need for genomic surveillance and targeted infection control strategies to curb the dissemination of emerging CRSM clones.