title: High levels of antibody in adults three years after vaccination with a reduced antigen content diphtheria-tetanus-acellular pertussis vaccine.
abstract: There is increasing interest in prevention of pertussis in adults by vaccination, but little is known about the duration of the antibody response to pertussis, diphtheria or tetanus in reduced antigen content vaccines formulated for adult use. Follow-up of a clinical trial including 550 adults comparing responses to reduced antigen content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, or a licensed Td vaccine, provided the opportunity to evaluate this. Blood samples were collected at 0, 1, 12, 24 and 36 months following vaccination; of the original cohort of 550, 387 subjects (dTpa group N=310, Td+pa group N=77) were tested at month 36. Following a decrease in antibody levels against all vaccine antigens between one and 24 months following vaccination, levels stabilized during the third year, remaining higher at 36 months than pre-vaccination for all vaccine antigens. In particular, more than 90% of subjects remained seropositive for pertussis toxin and pertactin antibodies at 36 months after vaccination, suggesting ongoing protection against pertussis. Adult-formulated dTpa vaccines could replace Td for routine booster vaccination of older individuals.
authors.affiliation: Centre for Immunisation Research, University of Sydney and the Royal Alexandra Hospital for Children, Locked Bag 4001, Westmead, NSW 2145, Australia. peterm@chw.edu.au
authors.forename: Peter B
authors.initials: PB
authors.lastname: McIntyre
authors.forename: Fiona M
authors.initials: FM
authors.lastname: Turnbull
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Egan
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Burgess
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Wolter
authors.forename: Lode M
authors.initials: LM
authors.lastname: Schuerman
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000008:administration & dosage / Q000276:immunology*; D015331:Cohort Studies; D022422:Diphtheria-Tetanus Vaccine / Q000008:administration & dosage / Q000276:immunology; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000008:administration & dosage / Q000276:immunology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007117:Immunization, Secondary; D008875:Middle Aged; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology; D016037:Single-Blind Method; D013997:Time Factors; D014611:Vaccination; D022282:Vaccines, Acellular / Q000008:administration & dosage / Q000276:immunology; D014917:Whooping Cough / Q000276:immunology* / Q000517:prevention & control
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D022422:Diphtheria-Tetanus Vaccine; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines; D010567:Pertussis Vaccine; D022282:Vaccines, Acellular