title: Better colonisation of newly emerged Bordetella pertussis in the co-infection mouse model study.
abstract: Molecular epidemiological data indicates that the resurgence of pertussis (whooping cough) in populations with high vaccine coverage is associated with genomic adaptation of Bordetella pertussis, the causative agent of the disease, to vaccine selection pressure. We have previously shown that in the period after the introduction of acellular pertussis vaccine (ACV), the majority of circulating strains in Australia switched to single nucleotide polymorphism (SNP) cluster I (carrying ptxP3/prn2), replacing SNP cluster II (carrying ptxP1/prn3). In this study, we carried out an in vivo competition assay using a mouse model infected with SNP cluster I and II B. pertussis strains from Australia. We found that the SNP cluster I strain colonised better than the SNP cluster II strain, in both naïve and immunised mice, suggesting that SNP cluster I strains had better fitness regardless of immunisation status of the host, consistent with SNP cluster I strains replacing SNP cluster II. Nevertheless, we found that ACV enhanced clearance of both SNP cluster I and II strains from the mouse respiratory tract.
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Safarchi
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Sophie
authors.initials: S
authors.lastname: Octavia
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Laurence Don Wai
authors.initials: LD
authors.lastname: Luu
authors.affiliation: Pathology and Laboratory Medicine, University of Western Australia, Perth, Western Australia, Australia.
authors.forename: Chin Yen
authors.initials: CY
authors.lastname: Tay
authors.affiliation: Centre for Infectious Diseases and Microbiology-Public Health, Institute of Clinical Pathology and Medical Research - Pathology West, Westmead Hospital, New South Wales, Australia; Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School, University of Sydney, New South Wales, Australia.
authors.forename: Vitali
authors.initials: V
authors.lastname: Sintchenko
authors.affiliation: National Centre for Immunisation Research and Surveillance, Children's Hospital at Westmead, New South Wales, Australia.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Wood
authors.affiliation: Vaccinology and Immunology Research Trials Unit, Women's and Children's Hospital and School of Paediatrics and Reproductive Health and Robinson Research Institute, University of Adelaide, South Australia, Australia.
authors.forename: Helen
authors.initials: H
authors.lastname: Marshall
authors.affiliation: National Centre for Immunisation Research and Surveillance, Children's Hospital at Westmead, New South Wales, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: McIntyre
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia. Electronic address: r.lan@unsw.edu.au.
authors.forename: Ruiting
authors.initials: R
authors.lastname: Lan
mesh_terms: D000818:Animals; D001315:Australia; D001886:Bordetella pertussis / Q000235:genetics*; D060085:Coinfection / Q000382:microbiology; D004195:Disease Models, Animal; D019143:Evolution, Molecular; D005260:Female; D056084:Genetic Fitness; D051379:Mice; D008807:Mice, Inbred BALB C; D010567:Pertussis Vaccine / Q000008:administration & dosage; D020641:Polymorphism, Single Nucleotide; D012137:Respiratory System / Q000382:microbiology; D012641:Selection, Genetic; D014917:Whooping Cough / Q000382:microbiology* / Q000517:prevention & control
chemical_list: D010567:Pertussis Vaccine
keywords: Acellular pertussis vaccine; Bordetella pertussis; Fitness; Mouse model infection; SNP cluster I; ptxP3 strain