title: WGS analysis and molecular resistance mechanisms of azithromycin-resistant (MIC >2 mg/L) Neisseria gonorrhoeae isolates in Europe from 2009 to 2014.
abstract: To elucidate the genome-based epidemiology and phylogenomics of azithromycin-resistant (MIC >2 mg/L) Neisseria gonorrhoeae strains collected in 2009-14 in Europe and clarify the azithromycin resistance mechanisms.
  
  
  
  Seventy-five azithromycin-resistant (MIC 4 to >256 mg/L) N. gonorrhoeae isolates collected in 17 European countries during 2009-14 were examined using antimicrobial susceptibility testing and WGS.
  
  
  
  Thirty-six N. gonorrhoeae multi-antigen sequence typing STs and five phylogenomic clades, including 4-22 isolates from several countries per clade, were identified. The azithromycin target mutation A2059G (Escherichia coli numbering) was found in all four alleles of the 23S rRNA gene in all isolates with high-level azithromycin resistance (n = 4; MIC ≥256 mg/L). The C2611T mutation was identified in two to four alleles of the 23S rRNA gene in the remaining 71 isolates. Mutations in mtrR and its promoter were identified in 43 isolates, comprising isolates within the whole azithromycin MIC range. No mutations associated with azithromycin resistance were found in the rplD gene or the rplV gene and none of the macrolide resistance-associated genes [mef(A/E), ere(A), ere(B), erm(A), erm(B), erm(C) and erm(F)] were identified in any isolate.
  
  
  
  Clonal spread of relatively few N. gonorrhoeae strains accounts for the majority of the azithromycin resistance (MIC >2 mg/L) in Europe. The four isolates with high-level resistance to azithromycin (MIC ≥256 mg/L) were widely separated in the phylogenomic tree and did not belong to any of the main clades. The main azithromycin resistance mechanisms were the A2059G mutation (high-level resistance) and the C2611T mutation (low- and moderate-level resistance) in the 23S rRNA gene.
authors.affiliation: Örebro University, Örebro, Sweden.
authors.forename: Susanne
authors.initials: S
authors.lastname: Jacobsson
authors.affiliation: Örebro University, Örebro, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Golparian
authors.affiliation: Public Health England, London, UK.
authors.forename: Michelle
authors.initials: M
authors.lastname: Cole
authors.affiliation: European Centre for Disease Prevention and Control, Stockholm, Sweden.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Spiteri
authors.affiliation: Public Health Agency of Canada, Winnipeg, Canada.
authors.forename: Irene
authors.initials: I
authors.lastname: Martin
authors.affiliation: Oslo University Hospital, Ullevål, Oslo, Norway.
authors.forename: Thea
authors.initials: T
authors.lastname: Bergheim
authors.affiliation: National Institute of Health, Lisbon, Portugal.
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Borrego
authors.affiliation: St James's Hospital, Dublin, Ireland.
authors.forename: Brendan
authors.initials: B
authors.lastname: Crowley
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Tania
authors.initials: T
authors.lastname: Crucitti
authors.affiliation: Public Health Service Amsterdam, Amsterdam, The Netherlands.
authors.forename: Alje P
authors.initials: AP
authors.lastname: Van Dam
authors.affiliation: Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Steen
authors.initials: S
authors.lastname: Hoffmann
authors.affiliation: Institute of Microbiology and Immunology, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: Samo
authors.initials: S
authors.lastname: Jeverica
authors.affiliation: Vivantes Klinikum Neukölln, Berlin, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Kohl
authors.affiliation: Medical University of Warsaw, Warsaw, Poland.
authors.forename: Beata
authors.initials: B
authors.lastname: Mlynarczyk-Bonikowska
authors.affiliation: Infectology Centre of Latvia, Riga, Latvia.
authors.forename: Gatis
authors.initials: G
authors.lastname: Pakarna
authors.affiliation: Outpatients' Centre for Infectious Venereodermatological Diseases, Vienna, Austria.
authors.forename: Angelika
authors.initials: A
authors.lastname: Stary
authors.affiliation: Istituto Superiore di Sanitá, Rome, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Stefanelli
authors.affiliation: HPL Laboratory Ltd, Bratislava, Slovakia.
authors.forename: Peter
authors.initials: P
authors.lastname: Pavlik
authors.affiliation: Hellenic Pasteur Institute, Athens, Greece.
authors.forename: Eva
authors.initials: E
authors.lastname: Tzelepi
authors.affiliation: Institute of Health Carlos III, Madrid, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Abad
authors.affiliation: Pathogen Genomics, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridgeshire, UK.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Harris
authors.affiliation: Örebro University, Örebro, Sweden magnus.unemo@regionorebrolan.se.
authors.forename: Magnus
authors.initials: M
authors.lastname: Unemo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017963:Azithromycin / Q000494:pharmacology*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005060:Europe / Q000453:epidemiology; D005260:Female; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D005838:Genotype; D006069:Gonorrhea / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D009344:Neisseria gonorrhoeae / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D010802:Phylogeny; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012338:RNA, Ribosomal, 23S; D017963:Azithromycin