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.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1086/513199 | DOI Listing |
Clin Microbiol Rev
January 2025
Department of Medicine, Division of Pulmonary/Allergy/Critical Care, The University of Alabama at Birmingham, Birmingham, Alabama, USA.
SUMMARY (the "pneumococcus") is a significant human pathogen. The key determinant of pneumococcal fitness and virulence is its ability to produce a protective polysaccharide (PS) capsule, and anti-capsule antibodies mediate serotype-specific opsonophagocytic killing of bacteria. Notably, immunization with pneumococcal conjugate vaccines (PCVs) has effectively reduced the burden of disease caused by serotypes included in vaccines but has also spurred a relative upsurge in the prevalence of non-vaccine serotypes.
View Article and Find Full Text PDFExpert Rev Vaccines
December 2025
South Africa Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa.
Background: Due to high costs of pneumococcal conjugate vaccines (PCV), transitioning from a two (2 + 1) to a single dose (1 + 1) primary series with a booster should be considered. This study evaluated the immune response at 18 months of age following a 1 + 1 compared to a 2 + 1 schedule of 10-valent (PCV10) and 13-valent (PCV13) vaccines.
Research Design And Methods: A single-center, open-label, randomized trial conducted in Soweto, South Africa, evaluated the immunogenicity of differing dosing schedule for PCV10 and PCV13.
J Infect
January 2025
Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, United States.
Background: Pneumococcal conjugate vaccines (PCVs) introduced in childhood national immunization programs lowered vaccine-type invasive pneumococcal disease (IPD), but replacement with non-vaccine-types persisted throughout the PCV10/13 follow-up period. We assessed PCV10/13 impact on pneumococcal meningitis incidence globally.
Methods: The number of cases with serotyped pneumococci detected in cerebrospinal fluid and population denominators were obtained from surveillance sites globally.
J Infect Chemother
January 2025
Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8576, Japan.
Introduction: We investigated clinical and microbiological characteristics of invasive Haemophilus influenzae disease (IHD) during recent 20 years in the Minami Ibaraki Area.
Methods: H. influenzae strains isolated from the blood and the cerebrospinal fluid in 5 hospitals located in this area between 2001 and 2020 (the pre-vaccination period [PreVP]: 2001-2010, the post-vaccination period [PostVP]: 2011-2020) were consecutively collected.
Zhonghua Yu Fang Yi Xue Za Zhi
January 2025
Immunization Program Institute of Shaanxi Provincial Center for Disease Control and Prevention, Xi'an 710054, China.
To investigate the safety of the tetravalent meningococcal conjugate vaccine (MPCV-ACYW) in combination with the inactivated poliomyelitis (IPV) vaccine and diphtheria-tetanus-acellular pertussis (DTaP) vaccine for infants aged 3-5 months and provide real-world evidence for the immunization strategy of vaccine combination. From June to October 2023, a total of 600 3-month-old infants were selected and divided into three groups: control group, mono-vaccination group and combined vaccination group. They were simultaneously or individually vaccinated with MPCV-ACYW, IPV and DTaP vaccines at 3, 4, and 5 months of age, respectively.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!