Immunogenicity for 16 serotypes of a unique schedule of pneumococcal vaccines in a high-risk population.
BACKGROUND
A unique schedule of 7-valent pneumococcal conjugate vaccine (7PCV) at 2, 4 and 6 months of age and 23-valent pneumococcal polysaccharide vaccine (23PPV) at 18 months commenced for Australian Aboriginal infants in 2001.


METHODS
Anti-capsular IgG concentrations in vaccinated and non-vaccinated (historic control) infants were determined (blinded) by (22F absorbed) ELISA.


RESULTS
One month after dose 3 of 7PCV, geometric mean concentrations (GMCs) were >1.95 microg/ml and at least 89% of infants had IgG >0.35 microg/ml to all 7PCV serotypes. One month post-23PPV, IgG to 7PCV serotypes was >0.35 microg/ml for more than 96% infants (>1.3 microg/ml for at least 70%), and IgG to non-7PCV serotypes was >0.35 microg/ml for more than 50% infants (including serotype 6A, but not 12F (17%) or 19A (44%).


CONCLUSIONS
7PCV and 23PPV are immunogenic in this population.
Menzies School of Health Research, Charles Darwin University, Darwin, Australia. amanda@menzies.edu.au
Amanda J
AJ
Leach
Peter S
PS
Morris
Grant
G
Mackenzie
Joseph
J
McDonnell
Anne
A
Balloch
Jonathan
J
Carapetis
Mimi
M
Tang
D000907:Antibodies, Bacterial / Q000097:blood; D001315:Australia; D016667:Bacterial Capsules / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007115:Immunization Schedule; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008137:Longitudinal Studies; D022401:Meningococcal Vaccines / Q000276:immunology*; D011008:Pneumococcal Infections / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000276:immunology*
C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines