title: Recent independent emergence of multiple multidrug-resistant Serratia marcescens clones within the United Kingdom and Ireland.
abstract: Serratia marcescens, a member of the Enterobacteriaceae family, is a Gram-negative bacterium responsible for a wide range of nosocomial infections. The emergence of multidrug-resistant strains is an increasing danger to public health. To design effective means to control the dissemination of S. marcescens, an in-depth analysis of the population structure and variation is required. Utilizing whole-genome sequencing, we characterized the population structure and variation, as well as the antimicrobial resistance determinants, of a systematic collection of antimicrobial-resistant S. marcescens associated with bloodstream infections in hospitals across the United Kingdom and Ireland between 2001 and 2011. Our results show that S. marcescens is a diverse species with a high level of genomic variation. However, the collection was largely composed of a limited number of clones that emerged from this diverse background within the past few decades. We identified potential recent transmissions of these clones, within and between hospitals, and showed that they have acquired antimicrobial resistance determinants for different beta-lactams, ciprofloxacin, and tetracyclines on multiple occasions. The expansion of these multidrug-resistant clones suggests that the treatment of S. marcescens infections will become increasingly difficult in the future.
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SA, United Kingdom;
authors.forename: Danesh
authors.initials: D
authors.lastname: Moradigaravand
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SA, United Kingdom;
authors.forename: Christine J
authors.initials: CJ
authors.lastname: Boinett
authors.affiliation: British Society for Antimicrobial Chemotherapy, Birmingham B1 3NJ, United Kingdom;
authors.forename: Veronique
authors.initials: V
authors.lastname: Martin
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SA, United Kingdom; Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, United Kingdom; London School of Hygiene and Tropical Medicine, London, WC1E 7HT, United Kingdom.
authors.forename: Sharon J
authors.initials: SJ
authors.lastname: Peacock
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SA, United Kingdom;
authors.forename: Julian
authors.initials: J
authors.lastname: Parkhill
mesh_terms: D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D003428:Cross Infection / Q000453:epidemiology / Q000235:genetics* / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D019143:Evolution, Molecular; D016680:Genome, Bacterial; D006801:Humans; D007494:Ireland; D012706:Serratia marcescens / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D006113:United Kingdom
chemical_list: D000900:Anti-Bacterial Agents