Characteristics of included studies (n = 54).

BackgroundStreptococcus pneumoniae is a leading cause of morbidity and mortality globally, causing bacteremic pneumonia, meningitis, sepsis, and other invasive pneumococcal diseases. Evidence supports nasopharyngeal pneumococcal carriage as a reservoir for transmission and precursor of pneumococcal disease.ObjectivesTo estimate the pneumococcal nasopharyngeal burden in all age groups in Latin America and the Caribbean (LAC) before, during, and after the introduction of pneumococcal vaccine conjugate (PVC).MethodsSystematic literature review of international, regional, and country-published and unpublished data, together with reports including data from serotype distribution in nasopharyngeal carriage in children and adults from LAC countries following Cochrane methods. The protocol was registered in PROSPERO database (ID: CRD42023392097).ResultsWe included 54 studies with data on nasopharyngeal pneumococcal carriage and serotypes from 31,803 patients. In children under five years old, carriage was found in 41% and in adults over 65, it was 26%. During the study period, children under five showed a colonization proportion of 34% with PCV10 serotypes and 45% with PCV13 serotypes. When we analyze the carriage prevalence of PCV serotypes in all age groups between 1995 and 2019, serotypes included in PCV10 and those included in PCV13, both showed a decreasing trend along analysis by lustrum.ConclusionThe data presented in this study highlights the need to establish national surveillance programs to monitor pneumococcal nasopharyngeal carriage to monitor serotype prevalence and replacement before and after including new pneumococcal vaccines in the region. In addition, to analyze differences in the prevalence of serotypes between countries, emphasize the importance of approaches to local realities to reduce IPD effectively.背景 肺炎链球菌（Streptococcus pneumoniae）是全球范围内导致高发病率与高死亡率的主要病原体之一，可引发菌血症性肺炎、脑膜炎、败血症及其他侵袭性肺炎球菌疾病。已有研究证实，鼻咽部肺炎球菌定植是病菌传播的储存库，亦是肺炎球菌疾病的前驱感染状态。目的 评估拉丁美洲及加勒比地区（Latin America and the Caribbean, LAC）在肺炎球菌结合疫苗（Pneumococcal Conjugate Vaccine, PVC）引入前、引入期间及引入后，各年龄段人群的鼻咽部肺炎球菌定植负荷。方法 本研究遵循Cochrane协作网方法学，对国际、区域及各国已发表与未发表的相关数据开展系统文献综述，同时纳入LAC国家儿童与成人鼻咽部肺炎球菌定植血清型分布相关报告。本研究方案已在PROSPERO数据库注册（编号：CRD42023392097）。结果 本研究共纳入54项研究，涉及31803名受试者的鼻咽部肺炎球菌定植及血清型相关数据。其中，5岁以下儿童的定植率为41%，65岁以上成人的定植率为26%。研究期间，5岁以下儿童携带10价肺炎球菌结合疫苗（PCV10）覆盖血清型的比例为34%，携带13价肺炎球菌结合疫苗（PCV13）覆盖血清型的比例为45%。对1995年至2019年间各年龄段人群的PCV覆盖血清型定植流行率进行分析后发现，PCV10与PCV13所覆盖的血清型定植率均呈现随五年周期逐步下降的趋势。结论 本研究数据提示，该区域亟需建立国家级监测体系，以监测肺炎球菌鼻咽部定植情况，追踪新型肺炎球菌疫苗引入前后的血清型流行率及血清型替换现象。此外，需开展各国血清型流行率差异分析，强调因地制宜制定防控策略的重要性，以有效降低侵袭性肺炎球菌疾病（Invasive Pneumococcal Diseases, IPD）的发生。