• Community carriage of ESBL-producing Escherichia coli and Klebsiella pneumoniae: a cross-sectional study of risk factors and comparative genomics of carriage and clinical isolates 

      Raffelsberger, Niclas Peter; Buczek, Dorota Julia; Svendsen, Kristian; Småbrekke, Lars; Pöntinen, Anna Kaarina; Löhr, Iren Høyland; Andreassen, Lotte Leonore Eivindsdatter; Simonsen, Gunnar Skov; Sundsfjord, Arnfinn Ståle; Gravningen, Kirsten; Samuelsen, Ørjan (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-12)
      The global prevalence of infections caused by extended-spectrum βlactamase-producing Enterobacterales (ESBL-E) is increasing, and for Escherichia coli, observations indicate that this is partly driven by community-onset cases. The ESBL-E population structure in the community is scarcely described, and data on risk factors for carriage are conflicting. Here, we report the prevalence and population ...
    • Emergence and dissemination of antimicrobial resistance in Escherichia coli causing bloodstream infections in Norway in 2002–17: a nationwide, longitudinal, microbial population genomic study 

      Gladstone, Rebecca Ashley; McNally, Alan; Pöntinen, Anna Kaarina; Tonkin-Hill, Gerry; Lees, John A.; Skytén, Kusti Onni; Cléon, Francois Pierre Alexandre; Christensen, Martin Owczarek Korsner; Haldorsen, Bjørg; Bye, Kristina K.; Gammelsrud, Karianne Wiger; Hjetland, Reidar; Kümmel, Angela; Larsen, Hege; Lindemann, Paul Christoffer; Löhr, Iren Høyland; Marvik, Åshild; Nilsen, Einar; Noer, Marie Therese; Simonsen, Gunnar Skov; Steinbakk, Martin; Tofteland, Ståle; Vattøy, Marit; Bentley, Stephen D.; Croucher, Nicholas J.; Parkhill, Julian; Johnsen, Pål Jarle; Samuelsen, Ørjan; Corander, Jukka (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-10)
      Background - The clonal diversity underpinning trends in multidrug resistant Escherichia coli causing bloodstream infections remains uncertain. We aimed to determine the contribution of individual clones to resistance over time, using large-scale genomics-based molecular epidemiology.<p> <p>Methods - This was a longitudinal, E coli population, genomic, cohort study that sampled isolates from ...
    • Evolutionary and functional history of the Escherichia coli K1 capsule 

      Alonso, Sergio Arredondo; Blundell-Hunter, George; Fu, Zuyi; Gladstone, Rebecca Ashley; Fillol-Salom, Alfred; Loraine, Jessica; Cloutman-Green, Elaine; Johnsen, Pål Jarle; Samuelsen, Ørjan; Pöntinen, Anna Kaarina; Cleon, Francois Pierre Alexandre; Chavez-Bueno, Susana; De la Cruz, Miguel A.; Ares, Miguel A.; Vongsouvath, Manivanh; Chmielarczyk, Agnieszka; Horner, Carolyne; Klein, Nigel; McNally, Alan; Reis, Joice N.; Penadés, José R.; Thomson, Nicholas R.; Corander, Jukka; Taylor, Peter W.; McCarthy, Alex J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-15)
      Escherichia coli is a leading cause of invasive bacterial infections in humans. Capsule polysaccharide has an important role in bacterial pathogenesis, and the K1 capsule has been firmly established as one of the most potent capsule types in E. coli through its association with severe infections. However, little is known about its distribution, evolution and functions across the E. coli phylogeny, ...
    • The first tigecycline resistant Enterococcus faecium in Norway was related to tigecycline exposure 

      Hegstad, Kristin; Pöntinen, Anna Kaarina; Bjørnholt, Jørgen; Paulsen, Else Quist; Sundsfjord, Arnfinn Ståle (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-19)
      Objectives - We describe the first tigecycline resistant enterococcal isolate in Norway and the mechanisms involved.<p> <p>Material and methods - The Norwegian National Advisory Unit on Detection of Antimicrobial Resistance (K-res). received in 2022 an Enterococcus faecium blood culture isolate with decreased susceptibility to tigecycline from a hospitalized patient in the South-Eastern Norway ...
    • Mge-cluster: a reference-free approach for typing bacterial plasmids 

      Alonso, Sergio Arredondo; Gladstone, Rebecca Ashley; Pöntinen, Anna Kaarina; Gama, João Alves; Schürch, Anita C.; Lanza, Val F.; Johnsen, Pål Jarle; Samuelsen, Ørjan; Tonkin-Hill, Gerry; Corander, Jukka (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-10)
      Extrachromosomal elements of bacterial cells such as plasmids are notorious for their importance in evolution and adaptation to changing ecology. However, high-resolution population-wide analysis of plasmids has only become accessible recently with the advent of scalable long-read sequencing technology. Current typing methods for the classification of plasmids remain limited in their scope which ...
    • Nationwide, population-based observational study of the molecular epidemiology and temporal trend of carbapenemase-producing Enterobacterales in Norway, 2015 to 2021 

      Ljungquist, Oskar; Haldorsen, Bjørg; Pöntinen, Anna Kaarina; Janice, Jessin; Josefsen, Ellen Haldis; Elstrøm, Petter; Kacelnik, Oliver; Sundsfjord, Arnfinn; Samuelsen, Ørjan; Handal, Nina; Ranheim, Trond Egil; Hansen, Bent-Are; Mjøen, Andreas Fossum; Lindemann, Paul Christoffer; Nilsen, Einar; Zaragkoulias, Kyriakos; Larsen, Hege Elisabeth; Bjørnholt, Jørgen; Gammelsrud, Karianne Wiger; Jakovljev, Aleksandra; Löhr, Iren Høyland; Bredberg, Anders; Marvik, Åshild; Minge, Christina; Tofteland, Ståle; Papp, Kristina; Onken, Annette; Weme, Einar Tollaksen; Guennigsman, Brian Albert (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-06)
      National and regional carbapenemaseproducing Enterobacterales (CPE) surveillance is essential to understand the burden of antimicrobial resistance, elucidate outbreaks, and develop infection-control or antimicrobial-treatment recommendations. Aim: This study aimed to describe CPE and their epidemiology in Norway from 2015 to 2021. Methods: A nationwide, population-based observational study of ...
    • Rapid cross-border emergence of NDM-5-producing Escherichia coli in the European Union/European Economic Area, 2012 to June 2022 

      Linkevicius, Marius; Bonnin, Rémy A; Alm, Erik; Svartström, Olov; Apfalter, Petra; Hartl, Rainer; Hasman, Henrik; Roer, Louise; Räisänen, Kati; Dortet, Laurent; Pfennigwerth, Niels; Hans, Jörg B; Tóth, Ákos; Buzgó, Lilla; Cormican, Martin; Delappe, Niall; Monaco, Monica; Giufrè, Maria; Hendrickx, Antoni Pa; Samuelsen, Ørjan; Pöntinen, Anna Kaarina; Caniça, Manuela; Manageiro, Vera; Oteo-Iglesias, Jesús; Pérez-Vázquez, María; Westmo, Karin; Mäkitalo, Barbro; Palm, Daniel; Monnet, Dominique L.; Kohlenberg, Anke (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-11)
      Whole genome sequencing data of 874 Escherichia coli isolates carrying blaNDM-5 from 13 European Union/ European Economic Area countries between 2012 and June 2022 showed the predominance of sequence types ST167, ST405, ST410, ST361 and ST648, and an increasing frequency of detection. Nearly a third (30.6%) of these isolates were associated with infections and more than half (58.2%) were ...
    • Strong pathogen competition in neonatal gut colonisation 

      Mäklin, Tommi; Thorpe, Harry Arthur Frank Wright; Pöntinen, Anna Kaarina; Gladstone, Rebecca Ashley; Shao, Yan; Pesonen, Maiju; McNally, Alan; Johnsen, Pål Jarle; Samuelsen, Ørjan; Lawley, Trevor D.; Honkela, Antti; Corander, Jukka (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-01)
      Opportunistic bacterial pathogen species and their strains that colonise the human gut are generally understood to compete against both each other and the commensal species colonising this ecosystem. Currently we are lacking a population-wide quantification of strain-level colonisation dynamics and the relationship of colonisation potential to prevalence in disease, and how ecological factors ...