Acute otitis media pneumococcal disease burden and nasopharyngeal colonization in children due to serotypes included and not included in current and new pneumococcal conjugate vaccines

ABSTRACT

Introduction

Despite the introduction of effective pneumococcal conjugate vaccines (PCV), Streptococcus pneumoniae remains a major cause of acute otitis media (AOM) worldwide. New, higher valency vaccines that offer broader serotype coverage have been recently developed and others are in development. However, given the capsular serotypes expressed by pneumococci causing AOM, it is unclear to what extent differing or higher valency PCVs will provide additional protection.

Areas Covered

We conducted a systematic literature search of the MEDLINE database to identify articles published from January 2016 to September 2021 in 4 low and middle income and 10 high-income countries. We searched PubMed with terms: (Streptococcus pneumoniae) OR pneumococcal AND serotype AND (conjugate vaccine). We evaluated serotype distribution and the actual or projected coverage of pneumococcal serotypes by PCV10 (GlaxoSmithKline), PCV13 (Pfizer), PCV10SII (Serum Institute of India) PCV15 (Merck) and PCV20 (Pfizer).

Expert Opinion

Our review highlights the important epidemiological differences in serotype distribution and coverage by existing and higher valency vaccines to protect against AOM in children. These data provide support for further evaluation of serotype-independent vaccines for optimal control of pneumococcal AOM disease worldwide.

KEYWORDS:

• Streptococcus pneumoniae
• pneumococcal conjugate vaccine
• acute otitis media
• epidemiology
• pneumococcal serotypes

Article highlights

• Pneumococcal serotypes among predominant strains causing AOM in South Asia and Southeast Asia, representing LMICs without widespread use of PCVs, resemble those observed in high-income countries before PCV introduction.

• Pneumococcal serotypes among predominant strains causing AOM in European countries, Israel and USA, representing high-income countries with high vaccine uptake rates, are predominantly caused by NVTs not included in higher valency PCVs.

• Serotype diversity in LMICs and serotype replacement in high-income countries represent a major challenge to serotype-dependent pneumococcal conjugate vaccine development for prevention of AOM.

Acknowledgments

Would like to thank the following people for supplying additional data: Drs. Esra Ekinci, Laura Willen and Prof. Heidi Theeten for the Belgium data, Drs. Ron Dagan and Bart Adrian Van Der Beek for the Israeli data, Ashish Bavdekar for the Indonesia and Bangladesh data and Dr Henry Baggett for the Thai data.

Declaration of interest

R Malley and P Anderson are co-inventors of a whole-cell pneumococcal vaccine in clinical development. R Malley owns stock in Affinvax, Inc. that has a pneumococcal vaccine in clinical development. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

M Pichichero substantially contributed to the conception and design of the review article and interpreting the relevant literature and was involved in all phases of writing. R Malley substantially contributed to revising the article for intellectual content. R Kaur substantially contributed to the writing and prepared the figures. R Zagursky performed the literature search, prepared the tables and contributed in the writing. P Anderson substantially contributed to the design and revising the article for intellectual content.

Additional information

Funding

This paper was not funded.