Almeida Sónia T, Paulo A Cristina, Simões Alexandra S, Ferreira Bárbara, Sá-Leão Raquel
Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Lisbon, Portugal.
mSphere. 2025 Jul 29;10(7):e0008225. doi: 10.1128/msphere.00082-25. Epub 2025 Jun 10.
(pneumococcus) is a leading cause of infections, particularly in infants and the elderly. Recent advances in molecular methods suggest higher pneumococcal carriage rates among adults than previously estimated, raising questions about their role in transmission. This study aimed to estimate pneumococcal carriage prevalence, identify circulating serotypes, and assess risk factors for colonization among adults during the COVID-19 pandemic in Portugal. We conducted a prospective observational study among civil servants aged ≥18 years in Oeiras Municipality from February 2021 to February 2022. Paired nasopharyngeal and oropharyngeal samples were analyzed using qPCR to detect pneumococcal carriage and 66 serotypes/serogroups. This included novel primers and probes for serotypes 4 and 24B/F, overcoming previous concerns associated with false positivity. Risk factors were identified using Bayesian adaptive sampling for variable selection in generalized linear model. Among 3,574 participants, 6.9% were pneumococcal carriers through qPCR without prior culture enrichment. Carriage rates were higher in oropharyngeal than nasopharyngeal samples (5.3% vs 3.7%, < 0.001). Twenty-six serotypes/serogroups were identified, with the most common being non-encapsulated (NT), 10A, 23B, 3, 11A/D, 33A/F/37, 16F, and 31. Excluding NT, the most frequent serotypes collectively accounted for 45.3% of all carriers. Vaccine coverage estimates were 13.5% for PCV13, 20.4% for PCV15, 40.0% for PCV20, and 64.1% for PCV21. Contact with children < 18 years increased the odds of colonization by 2.73-fold (95% confidence interval [CI], 2.01-3.75), while being male reduced the odds by 54% (odds ratio = 0.46; 95% CI, 0.30-0.69). These findings emphasize the need for ongoing surveillance to clarify adults' role in pneumococcal transmission and support prevention strategies, including adult vaccination and community-level interventions, to mitigate pneumococcal disease.IMPORTANCE is a major pathogen causing significant disease worldwide, yet adult carriage remains underexplored. By evaluating pneumococcal carriage among adults in Portugal during the COVID-19 pandemic, this study provides critical insights into circulating serotypes, including those not targeted by 13-valent pneumococcal conjugate vaccine (PCV13), and highlights key risk factors such as contact with children and sex differences. The findings reveal substantial potential coverage for newer PCVs. This work underscores the importance of adult-focused prevention strategies, including vaccination and ongoing surveillance, to reduce pneumococcal transmission and disease burden in the community.
肺炎球菌是感染的主要病因，尤其在婴儿和老年人中。分子方法的最新进展表明，成年人中肺炎球菌携带率高于先前估计，这引发了对其在传播中作用的质疑。本研究旨在估计葡萄牙新冠疫情期间成年人肺炎球菌携带率，确定流行血清型，并评估定植的危险因素。我们于2021年2月至2022年2月在奥埃拉什市对年龄≥18岁的公务员进行了一项前瞻性观察研究。使用qPCR分析配对的鼻咽和口咽样本，以检测肺炎球菌携带情况和66种血清型/血清群。这包括针对血清型4和24B/F的新型引物和探针，克服了先前与假阳性相关的问题。使用贝叶斯自适应抽样在广义线性模型中进行变量选择来确定危险因素。在3574名参与者中，通过qPCR检测，未经预先培养富集，6.9%为肺炎球菌携带者。口咽样本中的携带率高于鼻咽样本（5.3%对3.7%，<0.001）。确定了26种血清型/血清群，最常见的是非包膜型（NT）、10A、23B、3、11A/D、33A/F/37、16F和31。排除NT后，最常见的血清型合计占所有携带者的45.3%。13价肺炎球菌结合疫苗（PCV13）的疫苗接种覆盖率估计为13.5%，PCV15为20.4%，PCV20为40.0%，PCV21为64.1%。与18岁以下儿童接触使定植几率增加2.73倍（95%置信区间[CI]，2.01 - 3.75），而男性使几率降低54%（优势比 = 0.46；95% CI，0.30 - 0.69）。这些发现强调需要持续监测以阐明成年人在肺炎球菌传播中的作用，并支持预防策略，包括成人疫苗接种和社区层面的干预措施，以减轻肺炎球菌疾病。重要性肺炎球菌是在全球范围内导致重大疾病的主要病原体，但成人携带情况仍未得到充分研究。通过评估葡萄牙新冠疫情期间成年人的肺炎球菌携带情况，本研究为流行血清型提供了关键见解，包括那些13价肺炎球菌结合疫苗（PCV13）未针对的血清型，并突出了关键危险因素，如与儿童接触和性别差异。研究结果揭示了新型肺炎球菌结合疫苗（PCV）的巨大潜在覆盖率。这项工作强调了以成人为重点的预防策略的重要性，包括疫苗接种和持续监测，以减少社区内肺炎球菌的传播和疾病负担。
