TY - JOUR
T1 - Anticapsular serum antibody concentration and protection against pneumococcal colonization among children vaccinated with 7-valent pneumococcal conjugate vaccine
AU - Millar, Eugene V.
AU - O'Brien, Katherine L.
AU - Bronsdon, Melinda A.
AU - Madore, Dace
AU - Hackell, Jill G.
AU - Reid, Raymond
AU - Santosham, Mathuram
N1 - Funding Information:
Potential conflicts of interest. K.L.O. has received consultations, honoraria, or travel grants from Wyeth Vaccines. D.M. was employed by Wyeth Vaccines at the time this study was conducted. J.G.H. is an employee of Wyeth Vaccines. M.S. received consultations, honoraria, and travel grants from Wyeth Vaccines. All other authors: no conflicts.
PY - 2007/5/1
Y1 - 2007/5/1
N2 - Background. Pneumococcal conjugate vaccines prevent invasive and noninvasive disease due to infection with vaccine serotypes. Pneumococcal conjugate vaccines also prevent nasopharyngeal acquisition of vaccine serotypes, although the mechanism is incompletely understood. Methods. An efficacy trial of a 7-valent pneumococcal conjugate vaccine was conducted on the Navajo and White Mountain Apache reservations, located in the Southwestern United States; group C meningococcal conjugate vaccine was the control vaccine. Infants were randomized to receive 7-valent pneumococcal conjugate vaccine or group C meningococcal conjugate vaccine at 2, 4, 6, and 12 months of age. Immunogenicity and nasopharyngeal colonization studies were nested in the efficacy trial. We analyzed the correlation between serotype-specific serum IgG concentration at 7 and 13 months of age and nasopharyngeal acquisition of disease at 12 and 18 months of age, respectively. We adjusted for potential confounders using multivariate logistic regression. Results. Among 203 subjects, we observed 60 acquisitions of vaccine-type pneumococci, including 19 acquisitions of serotype 19F (31.7%), and 17 acquisitions of serotype 23F (28.3%). Among recipients of 7-valent pneumococcal conjugate vaccine, increased serotype-specific serum IgG was associated with a reduction in nasopharyngeal acquisition of serotype 23F (relative risk, 0.53; 95% confidence interval, 0.31-0.93) but was not associated with a reduction in acquisition of serotype 19F (relative risk, 1.07; 95% confidence interval, 0.57-2.03). Among group C meningococcal conjugate vaccine recipients, serotype-specific serum IgG was not associated with a reduction in nasopharyngeal acquisition for either serotype. Conclusion. An increase in serum antibody concentration was associated with reduced acquisition of serotype 23F pneumococcus (but not with reduced acquisition of serotype 19F pneumococcus) among recipients of 7-valent pneumococcal conjugate vaccine. Differences in antibody concentration, in the functional characteristics of antibody, or in antibody kinetics during infancy may account for differences in carriage protection.
AB - Background. Pneumococcal conjugate vaccines prevent invasive and noninvasive disease due to infection with vaccine serotypes. Pneumococcal conjugate vaccines also prevent nasopharyngeal acquisition of vaccine serotypes, although the mechanism is incompletely understood. Methods. An efficacy trial of a 7-valent pneumococcal conjugate vaccine was conducted on the Navajo and White Mountain Apache reservations, located in the Southwestern United States; group C meningococcal conjugate vaccine was the control vaccine. Infants were randomized to receive 7-valent pneumococcal conjugate vaccine or group C meningococcal conjugate vaccine at 2, 4, 6, and 12 months of age. Immunogenicity and nasopharyngeal colonization studies were nested in the efficacy trial. We analyzed the correlation between serotype-specific serum IgG concentration at 7 and 13 months of age and nasopharyngeal acquisition of disease at 12 and 18 months of age, respectively. We adjusted for potential confounders using multivariate logistic regression. Results. Among 203 subjects, we observed 60 acquisitions of vaccine-type pneumococci, including 19 acquisitions of serotype 19F (31.7%), and 17 acquisitions of serotype 23F (28.3%). Among recipients of 7-valent pneumococcal conjugate vaccine, increased serotype-specific serum IgG was associated with a reduction in nasopharyngeal acquisition of serotype 23F (relative risk, 0.53; 95% confidence interval, 0.31-0.93) but was not associated with a reduction in acquisition of serotype 19F (relative risk, 1.07; 95% confidence interval, 0.57-2.03). Among group C meningococcal conjugate vaccine recipients, serotype-specific serum IgG was not associated with a reduction in nasopharyngeal acquisition for either serotype. Conclusion. An increase in serum antibody concentration was associated with reduced acquisition of serotype 23F pneumococcus (but not with reduced acquisition of serotype 19F pneumococcus) among recipients of 7-valent pneumococcal conjugate vaccine. Differences in antibody concentration, in the functional characteristics of antibody, or in antibody kinetics during infancy may account for differences in carriage protection.
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U2 - 10.1086/513199
DO - 10.1086/513199
M3 - Article
C2 - 17407035
AN - SCOPUS:34247232697
VL - 44
SP - 1173
EP - 1179
JO - Clinical Infectious Diseases
JF - Clinical Infectious Diseases
SN - 1058-4838
IS - 9
ER -