title: Genetic Variation of Bordetella pertussis in Austria.
abstract: In Austria, vaccination coverage against Bordetella pertussis infections during infancy is estimated at around 90%. Within the last years, however, the number of pertussis cases has increased steadily, not only in children but also in adolescents and adults, indicating both insufficient herd immunity and vaccine coverage. Waning immunity in the host and/or adaptation of the bacterium to the immunised hosts could contribute to the observed re-emergence of pertussis. In this study we therefore addressed the genetic variability in B. pertussis strains from several Austrian cities. Between the years 2002 and 2008, 110 samples were collected from Vienna (n = 32), Linz (n = 63) and Graz (n = 15) by nasopharyngeal swabs. DNA was extracted from the swabs, and bacterial sequence polymorphisms were examined by MLVA (multiple-locus variable number of tandem repeat analysis) (n = 77), by PCR amplification and conventional Sanger sequencing of the polymorphic regions of the prn (pertactin) gene (n = 110), and by amplification refractory mutation system quantitative PCR (ARMS-qPCR) (n = 110) to directly address polymorphisms in the genes encoding two pertussis toxin subunits (ptxA and ptxB), a fimbrial adhesin (fimD), tracheal colonisation factor (tcfA), and the virulence sensor protein (bvgS). Finally, the ptxP promoter region was screened by ARMS-qPCR for the presence of the ptxP3 allele, which has been associated with elevated production of pertussis toxin. The MLVA analysis revealed the highest level of polymorphisms with an absence of MLVA Type 29, which is found outside Austria. Only Prn subtypes Prn1/7, Prn2 and Prn3 were found with a predominance of the non-vaccine type Prn2. The analysis of the ptxA, ptxB, fimD, tcfA and bvgS polymorphisms showed a genotype mixed between the vaccine strain Tohama I and a clinical isolate from 2006 (L517). The major part of the samples (93%) displayed the ptxP3 allele. The consequences for the vaccination strategy are discussed.
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Birgit
authors.initials: B
authors.lastname: Wagner
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria; Astellas Pharma, Vienna, Austria.
authors.forename: Helen
authors.initials: H
authors.lastname: Melzer
authors.affiliation: Genomics Core Facility, VetCore, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Freymüller
authors.affiliation: Department of Hygiene, Microbiology and Tropical Medicine, Elisabethinen Hospital, Linz, Austria; analyse BioLab, Linz, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Stumvoll
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria; Federal Ministry of Health, Vienna, Austria.
authors.forename: Pamela
authors.initials: P
authors.lastname: Rendi-Wagner
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria; Federal Ministry of Health, Vienna, Austria.
authors.forename: Maria
authors.initials: M
authors.lastname: Paulke-Korinek
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Repa
authors.affiliation: Centre for Infectious Diseases Control, National Institute of Public Health and the Environment, Bilthoven, The Netherlands.
authors.forename: Frits R
authors.initials: FR
authors.lastname: Mooi
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Herwig
authors.initials: H
authors.lastname: Kollaritsch
authors.affiliation: Department of Hygiene, Microbiology and Tropical Medicine, Elisabethinen Hospital, Linz, Austria; analyse BioLab, Linz, Austria.
authors.forename: Helmut
authors.initials: H
authors.lastname: Mittermayer
authors.affiliation: Department of Hygiene, Microbiology and Environmental Medicine, Medical University Graz, Graz, Austria.
authors.forename: Harald H
authors.initials: HH
authors.lastname: Kessler
authors.affiliation: Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Gerold
authors.initials: G
authors.lastname: Stanek
authors.affiliation: Genomics Core Facility, VetCore, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Ralf
authors.initials: R
authors.lastname: Steinborn
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Duchêne
authors.affiliation: Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Ursula
authors.initials: U
authors.lastname: Wiedermann
mesh_terms: D000293:Adolescent; D000328:Adult; D001317:Austria / Q000453:epidemiology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015373:Bacterial Typing Techniques; D001483:Base Sequence; D001886:Bordetella pertussis / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D005260:Female; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D017589:Immunization Programs / Q000458:organization & administration*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D009305:Nasopharynx / Q000276:immunology / Q000382:microbiology; D037342:Pertussis Toxin / Q000235:genetics / Q000378:metabolism; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology*; D011110:Polymorphism, Genetic; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014611:Vaccination; D010566:Virulence Factors, Bordetella / Q000235:genetics / Q000378:metabolism; D014917:Whooping Cough / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D010567:Pertussis Vaccine; D021122:Protein Subunits; D014157:Transcription Factors; D010566:Virulence Factors, Bordetella; C080662:bvgS protein, Bordetella pertussis; C489284:fimD protein, Bordetella; C096309:tracheal colonization factor, Bordetella pertussis; D036781:Fimbriae Proteins; D037342:Pertussis Toxin