title: The utility of seroepidemiology for tracking trends in pertussis infection.
abstract: Comparing pertussis epidemiology over time and between countries is confounded by differences in diagnostic and notification practices. Standardized serological methods applied to population-based samples enhance comparability. Population prevalence of different levels of pertussis toxin IgG (PT IgG) antibody, measured by standardized methods, were compared by age group and region of Australia between 1997/1998 and 2002. The proportion of 5- to 9-year-olds with presumptive recent pertussis infection (based on IgG levels >or=62.5 ELISA units/ml) significantly decreased in 2002, consistent with notification data for the same period and improved uptake of booster vaccines following the schedule change from whole-cell to acellular vaccine. In contrast, recent presumptive infection significantly increased in adults aged 35-49 years. Population-based serosurveillance using standardized PT IgG antibody assays has the potential to aid interpretation of trends in pertussis incidence in relation to vaccine programmes and between countries.
authors.affiliation: The National Centre for Immunisation Research and Surveillance of Vaccine Preventable Diseases, The Children's Hospital at Westmead and The University of Sydney, Australia. helenq@chw.edu.au
authors.forename: H E
authors.initials: HE
authors.lastname: Quinn
authors.forename: P B
authors.initials: PB
authors.lastname: McIntyre
authors.forename: J L
authors.initials: JL
authors.lastname: Backhouse
authors.forename: H F
authors.initials: HF
authors.lastname: Gidding
authors.forename: J
authors.initials: J
authors.lastname: Brotherton
authors.forename: G L
authors.initials: GL
authors.lastname: Gilbert
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000907:Antibodies, Bacterial / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008875:Middle Aged; D037342:Pertussis Toxin / Q000276:immunology; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D014917:Whooping Cough / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D037342:Pertussis Toxin