title: Evidence of Bordetella pertussis infection in vaccinated 1-year-old Danish children.
abstract: We measured IgA and IgG antibodies to pertussis toxin (PT) and filamentous hemagglutinin (FHA) in sera from 203 1-year-old children who had received one to three doses of a monocomponent PT toxoid vaccine. Ten children (5%) had IgA antibody to PT indicating recent infection; seven of these children had received three doses of vaccine. PT IgA responders did not have significantly longer coughing episodes than PT IgA non-responders. Since an IgA antibody response occurs in only approximately 50% of infected children, the actual infection rate in our cohort is estimated to approximately 10%. The apparent high Bordetella pertussis infection rate in Danish infants suggests that the monocomponent PT toxoid vaccine used in Denmark has limited efficacy against B. pertussis infection. A prospective immunization study comparing a multi-component vaccine with the present monocomponent PT toxoid vaccine should be undertaken.
authors.affiliation: Department of Pediatrics, Hvidovre Hospital, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: von Linstow
authors.forename: Peter Lotko
authors.initials: PL
authors.lastname: Pontoppidan
authors.forename: Carl-Heinz Wirsing
authors.initials: CH
authors.lastname: von König
authors.forename: James D
authors.initials: JD
authors.lastname: Cherry
authors.forename: Birthe
authors.initials: B
authors.lastname: Hogh
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D001886:Bordetella pertussis / Q000276:immunology*; D015331:Cohort Studies; D003718:Denmark; D005260:Female; D006388:Hemagglutinins / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008297:Male; D037342:Pertussis Toxin / Q000276:immunology*; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology*; D014611:Vaccination / Q000379:methods*; D014917:Whooping Cough / Q000517:prevention & control*
chemical_list: D000907:Antibodies, Bacterial; D006388:Hemagglutinins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D010567:Pertussis Vaccine; D037342:Pertussis Toxin