Serotypes associated with invasive pneumococcal disease high-risk groups: a systematic review

Area of Science:

• Immunology
• Vaccinology
• Public Health

Background:

• Invasive pneumococcal diseases (IPDs) pose a significant threat, particularly to high-risk populations.
• The 13-valent pneumococcal conjugate vaccine (PCV13) is a key tool, but higher-valent vaccines are being developed.
• Assessing the efficacy of higher-valent vaccines in specific high-risk groups is crucial.

Purpose of the Study:

• To determine if higher-valent pneumococcal conjugate vaccines offer superior coverage and protection compared to PCV13 in high-risk populations.
• To analyze serotype distribution and vaccine coverage across different high-risk groups.

Main Methods:

• Systematic review of original articles from PubMed, Science Direct, and Google Scholar.
• Inclusion criteria focused on study type, period, high-risk groups, specimens, isolate numbers, and serotype data.
• Data extraction from 14 studies across seven countries, analyzing 789 isolates.

Main Results:

• No significant difference in the frequency of non-vaccine (51.6%) versus vaccine (48.4%) serotypes was observed.
• The 23-valent pneumococcal polysaccharide vaccine (PPV23) demonstrated the highest serotype coverage (36.5% ± 5.3%) in high-risk groups.
• Serotype coverage varied by group, highest in cancer patients (26.2%–40.5%) and lowest in sickle cell disease patients (20%–28.9%).

Conclusions:

• Higher-valent pneumococcal vaccines may offer significantly improved coverage for individuals at high risk of IPDs.
• Continuous surveillance of serotypes prevalent in high-risk groups is essential for optimizing vaccination strategies.
• The findings underscore the need for tailored vaccine approaches for diverse high-risk populations.