Immunogenicity and safety of 13-valent pneumococcal conjugate vaccine in Mexico

Area of Science:

• Pediatric infectious diseases
• Vaccinology
• Immunology

Background:

• Pneumococcal conjugate vaccines are crucial for preventing invasive pneumococcal disease.
• Mexico's routine childhood immunization program aims to protect infants from vaccine-preventable diseases.

Purpose of the Study:

• To evaluate the safety and immunogenicity of the 13-valent pneumococcal conjugate vaccine (PCV13) in infants in Mexico.
• To assess immune responses following PCV13 administration alongside other routine childhood vaccinations.

Main Methods:

• A study involving 225 infants in Mexico administered PCV13 at 2, 4, 6, and 12 months of age.
• Simultaneous administration of PCV13 with other standard pediatric vaccines.
• Measurement of immunoglobulin G (IgG) concentrations and assessment of local and systemic reactions.

Main Results:

• High proportions of infants achieved protective IgG concentrations (≥0.35 µg/mL) for all 13 serotypes, with rates ≥93.1% after the infant series and ≥96.7% after the toddler dose.
• Serotype-specific IgG geometric mean concentrations were robust, ranging from 1.18 to 9.13 µg/mL post-infant series and 1.62 to 15.41 µg/mL post-toddler dose.
• The most frequent adverse events were local tenderness and systemic irritability; most fevers were mild, with no severe cases reported. One case of Kawasaki disease was deemed unrelated to PCV13.

Conclusions:

• PCV13 is safe and immunogenic when administered with routine pediatric vaccines in healthy infants in Mexico.
• The vaccine elicited significant antibody responses, suggesting effective protection against the targeted pneumococcal serotypes.