Pertussis antibody levels in infants immunized with an acellular pertussis component vaccine, measured using whole-cell pertussis ELISA.
A commercially available whole-cell pertussis IgG ELISA was used to test the response of 137 2-month-old infants to immunization with a trivalent acellular pertussis vaccine. The pre-immunization geometric mean (GM) IgG index was 6.96 (95% confidence interval (CI) 5.88-8.04) and the postimmunization GM index was 13.16 (95% CI 12. 20-14.11), P < 0.001. Eighty percent of subjects (110/137) had a significant 1.5-fold increase of pertussis IgG index (97/137, 71%) or a postimmunization IgG index > 10 (93/137, 68%). In single antigen ELISA, 83% showed at least a fourfold increase in pertussis toxin-specific IgG (PT-IgG) and 91% showed an increase in IgG specific for filamentous haemagglutinin (FHA-IgG). Four percent had high pre- immunization antibody levels (index > 20), likely to reflect recent maternal exposure to pertussis. This correlated with a smaller increase in pertussis IgG index. A decline in pertussis IgG index postimmunization occurred in 17/24 infants (71%) whose pre-immunization IgG index was > 10. This postimmunization pertussis IgG index was not significantly different to that of infants with a low pre-immunization index. A similar trend was noted with PT-IgG and FHA-IgG results. The whole-cell ELISA can detect a response to acellular pertussis vaccination in most infants if both antibody index and degree of seroconversion are calculated and at least one criterion is satisfied.
Hanlon
M
M
Department of Immunology and Infectious Diseases, New Children's Hospital, Westmead, New South Wales, Windsor, Queensland, Australia. markh@nch.edu.au
Nambiar
R
R
Kakakios
A
A
McIntyre
P
P
Land
M
M
Devine
P
P
D000907:Antibodies, Bacterial / Q000097:blood*; D001886:Bordetella pertussis / Q000276:immunology*; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000276:immunology*; D011933:Reagent Kits, Diagnostic; D014917:Whooping Cough / Q000175:diagnosis / Q000517:prevention & control
D000907:Antibodies, Bacterial; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D007074:Immunoglobulin G; D010567:Pertussis Vaccine; D011933:Reagent Kits, Diagnostic