Estimated pneumococcal disease burden in children due to serotypes covered by different pneumococcal conjugate vaccines in five Latin American countries.

Introduction: The widespread implementation of pneumococcal conjugate vaccines (PCVs) into pediatric national immunization programs (NIPs) across Latin American countries has substantially reduced pneumococcal disease burden. While the 10-valent (PCV10) and 13-valent (PCV13) vaccines have reduced morbidity and mortality, disease caused by serotypes not included in these vaccines persists. The 15-valent (PCV15) and 20-valent (PCV20) vaccines are now available in the region. This study aimed to estimate the clinical, economic, and societal burden attributable to serotypes contained in PCV10, PCV13, PCV15, and PCV20 in children aged <5 years in Argentina, Chile, Mexico, Colombia, and Brazil. Methods: Using country-specific epidemiological, cost, and population inputs, we applied a static Excel-based model to estimate annual pneumococcal disease cases, deaths, direct medical costs, and indirect societal costs resulting from caregiver productivity losses. Burden was estimated for serotypes included in PCV10, PCV13, PCV15, and PCV20, and results were interpreted in the context of the vaccine included in each country's pediatric NIP as of 2019. Results: Across the five countries, PCV20 serotypes were estimated to cause over 510,000 pneumococcal disease cases and approximately 2,700 deaths annually. This corresponded to an annual economic burden exceeding USD $182 million and a societal burden exceeding USD $34 million. Non-invasive disease, particularly pneumonia and otitis media, accounted for most of the clinical, economic, and societal burden. In countries using PCV10 in their NIP, a substantial proportion of remaining disease burden was attributable to serotypes included in PCV13 but not PCV10. Across all countries, serotypes unique to PCV15 contributed little additional burden beyond PCV13, whereas serotypes unique to PCV20 accounted for a substantial share of remaining disease burden, particularly in PCV13 NIP countries. Conclusion: Despite the success of PCV10 and PCV13 in reducing pneumococcal disease in Latin America, a considerable clinical, economic, and societal burden remains due to serotypes included in higher-valent vaccines. Broader serotype coverage offered by PCV20 has the potential to address this unmet burden and further reduce the public health and economic impact of pneumococcal disease in young children across the region.