Assessing the impact of childhood pneumococcal vaccination on pneumonia mortality in Colombia: a 14-year analysis

The 10-valent pneumococcal conjugate vaccine (PCV10) has been offered to all infants through Colombia’s National Immunization Program (NIP) since 2012, with catch-up vaccination until age 5. However, pneumococcal vaccination is not currently included in the NIP for other age groups, such as those ≥ 5 years with medical conditions or older adults. This study assessed the pediatric PCV10 effect on pneumonia mortality rate (MR) trends across different age groups from 2006 to 2019. This retrospective time-series study utilized the national death registration data. Deaths caused by pneumonia as the underlying cause of death were identified via ICD-10 codes and stratified by age groups (< 1, 1–4, 5–17, 18–49, 50–59, and ≥ 60 years). Crude MR, age-adjusted MR, and age-specific MRs per 100,000 population were calculated. Trends were assessed using joinpoint regression and expressed as annual percentage change (APC) and average APC in the pre-PCV10 (2006–2011), post-PCV10 (2013–2019), early post-PCV10 (2013–2016), and late post-PCV10 (2017–2019) periods. From 2006 to 2019, there were 102,082 pneumonia-related deaths. The age-specific MR for infants < 1 year significantly decreased from 83.8 to 28.6 per 100,000 between 2006 and 2019 (APC:-6.9), while for children aged 1–4 years, it decreased from 9.3 to 3.8 (APC:-5.1). Other older age groups exhibited stable trends in the post-PCV10 period, except for adults aged ≥ 60 years, who had the highest age-specific MR (~ 112 per 100,000) over the study period, with an AAPC of 6.5% in the early post-PCV10 period, followed by stable trends in the late post-PCV10 period. The age-adjusted MR showed an increasing trend with an APC of 1.9% from 2008 to 2019. Our study found decreasing age-specific MR trends in children under 5 in the post-PCV10 period; however, no evidence of indirect benefits was seen in unvaccinated age groups older than 5 years. The findings underscore the need to expand pneumococcal vaccination programs to other age groups, mainly adults ≥ 60 years.