Pneumococcal conjugate vaccines for preventing otitis media

Area of Science:

• Immunology
• Pediatrics
• Vaccinology

Background:

• Acute otitis media (AOM) is a common childhood infection, driving the need for preventative vaccines due to antibiotic resistance and healthcare costs.
• The search for effective vaccines to prevent AOM is crucial given the limitations of antibiotic treatments in low-risk populations.

Purpose of the Study:

• To evaluate the efficacy of pneumococcal conjugate vaccines (PCVs) in preventing AOM in children up to 12 years of age.

Main Methods:

• Systematic review of randomized controlled trials (RCTs) identified through comprehensive database searches (CENTRAL, MEDLINE, EMBASE, CINAHL, LILACS, Web of Science).
• Included RCTs involved children aged 12 years or younger, vaccinated with PCVs, and followed for at least six months.
• Trial quality was independently assessed, and data extracted by two reviewers; heterogeneity precluded meta-analysis.

Main Results:

• Eleven publications from nine RCTs (n=48,426) assessed 7- to 11-valent PCVs.
• The 7-valent CRM197-PCV7 showed a modest risk reduction for AOM in healthy infants (4-9%) but no benefit in high-risk children (-25% to 12%).
• Other PCVs demonstrated varied efficacy, with one 11-valent PCV showing a 34% reduction, while PCV7 after infancy showed no benefit and potentially negative effects.

Conclusions:

• The 7-valent CRM197-PCV7 offers modest benefits for preventing AOM in healthy, low-risk infants.
• PCV7 administration in high-risk infants, post-infancy, or in older children with AOM history provides no additional preventive benefit.
• Ongoing trials with new multivalent PCVs are needed to clarify their role in AOM prevention, alongside further investigation into the impact of specific carrier proteins.