Background Pneumococcal conjugate vaccines (PCVs) provide strong direct protection in children, while limited data are available on their indirect effect on mortality among older age groups. This multi-country study aimed to assess the population-level impact of pediatric PCVs on all-cause pneumonia mortality among ≥5 years of age, and invasive pneumococcal disease (IPD) cases in Chile. Methods Demographic and mortality data from Argentina, Brazil, Chile, Colombia, and Mexico were collected considering the ≥ 5-year-old population, from 2000-2019, with 1,795,789 deaths due to all-cause pneumonia. IPD cases in Chile were also evaluated. Time series models were employed to evaluate changes in all-cause pneumonia deaths during the post-vaccination period, with other causes of death used as synthetic controls for unrelated temporal trends. Results No significant change in death rates due to all-cause pneumonia was detected following PCV introduction among most age groups and countries. The proportion of IPD cases caused by vaccine serotypes decreased from 29% (2012) to 6% (2022) among ≥65 years in Chile. Discussion While an effect of PCV against pneumonia deaths (a broad clinical definition that may not be specific enough to measure indirect effects) was not detected, evidence of indirect PCV impact was observed among vaccine-type-specific IPD cases.

中文翻译：

---

肺炎球菌结合疫苗对五个拉丁美洲国家未接种疫苗的年龄组中全因肺炎死亡率的估计人群影响

背景 肺炎球菌结合疫苗（PCV）为儿童提供强有力的直接保护，而关于其对老年人群死亡率的间接影响的数据有限。这项多国研究旨在评估儿童 PCV 对智利 5 岁以上全因肺炎死亡率和侵袭性肺炎球菌病 (IPD) 病例的人群影响。方法收集了阿根廷、巴西、智利、哥伦比亚和墨西哥 2000 年至 2019 年 5 岁及以上人口的人口统计和死亡率数据，其中 1,795,789 人死于全因肺炎。还对智利的 IPD 病例进行了评估。采用时间序列模型来评估疫苗接种后期间全因肺炎死亡的变化，并使用其他死因作为不相关时间趋势的综合对照。结果 在大多数年龄组和国家引入 PCV 后，未发现全因肺炎死亡率发生显着变化。在智利 65 岁以上人群中，由疫苗血清型引起的 IPD 病例比例从 29%（2012 年）下降到 6%（2022 年）。讨论 虽然未检测到 PCV 对肺炎死亡的影响（广泛的临床定义，可能不够具体，无法衡量间接影响），但在疫苗类型特异性 IPD 病例中观察到 PCV 间接影响的证据。