Vaccine effectiveness of PCV13 in a 3+1 vaccination schedule

Area of Science:

• Pediatric Infectious Diseases
• Vaccinology
• Epidemiology

Background:

• Invasive pneumococcal disease (IPD) remains a significant public health concern in children.
• The 13-valent pneumococcal conjugate vaccine (PCV13) targets specific Streptococcus pneumoniae serotypes.
• Understanding vaccine effectiveness (VE) for different serotypes and vaccination schedules is crucial for public health policy.

Purpose of the Study:

• To evaluate the vaccine effectiveness (VE) of PCV13 against invasive pneumococcal disease (IPD) caused by six additional serotypes.
• To assess the impact of a 3+1 vaccination schedule in children under 16 years in Germany.

Main Methods:

• Active surveillance for IPD cases in children eligible for PCV13 vaccination.
• Utilized the Broome method and logistic regression to estimate vaccine effectiveness.
• Included 164 informative IPD cases meeting the study's inclusion criteria.

Main Results:

• PCV13 demonstrated 88% VE for at least one dose and 83% VE for at least two doses against the six extra serotypes.
• VE for the complete 3+1 schedule was inconclusive due to wide confidence intervals.
• Effectiveness against serotype 3 appeared to be zero, with very wide confidence intervals.

Conclusions:

• PCV13 exhibits significant VE against the targeted extra serotypes in a 3+1 schedule.
• The VE for the 3+1 schedule was only marginally higher than previously reported for a 2+1 schedule.
• Further investigation is needed for conclusive results on the 3+1 schedule's overall effectiveness, particularly for serotype 3.