Wen Wang

Objectives: To evaluate the real-world effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in reducing all-cause, pneumonia-related, and chronic obstructive pulmonary disease (COPD)-related mortality in adults aged ≥60 years. Methods: In this retrospective cohort study using existing health surveillance data, individuals aged ≥60 years on 1 January 2020 were followed until 31 August 2025 and classified by PPSV23 vaccination status. Propensity score matching (PSM) at a 1:1 ratio balanced sex, age, regional distribution, urbanization level and influenza vaccination status. Time-dependent Cox proportional hazards models estimated hazard ratios (HR) and vaccine effectiveness (VE), defined as (1 − HR) × 100%. Subgroup, negative control (mortality from traffic accidents), and E-value sensitivity analyses were performed. Results: After PSM, 453,500 individuals were included, with a mean follow-up of 5.61 years. All-cause mortality was 3.93 per 1000 person-years in vaccinated versus 9.57 in unvaccinated individuals. PPSV23 vaccination reduced all-cause mortality (VE = 43.1%, 95% CI: 41.2–45.0%), pneumonia-related mortality (VE = 46.2%, 95% CI: 39.6–52.1%), and COPD-related mortality (VE = 33.5%, 95% CI: 20.9–44.2%) (all p < 0.001). In a cause-specific decomposition, pneumonia- and COPD-related deaths together explained only 14.9% of the absolute reduction in all-cause deaths, whereas circulatory diseases and malignant tumors accounted for 36.8% and 31.9%, respectively. Among those also vaccinated against influenza, VE was 48.0% and 38.2% for pneumonia- and COPD-related mortality, respectively. For COPD-related mortality, the benefit was greater in men (VE = 42.3%) and in those aged ≥70 years (70–79 years, VE = 45.6%; ≥80 years, VE = 52.0%). PPSV23 was not associated with the negative control outcome (p = 0.247); E-values (1.98–2.44) indicated robustness to unmeasured confounding. Conclusions: PPSV23 vaccination was associated with significantly lower all-cause, pneumonia-related, and COPD-related mortality among elderly individuals aged ≥60 years. However, the observed association with all-cause mortality should be interpreted cautiously. Continued promotion of PPSV23 vaccination and advocacy for combined influenza–pneumococcal vaccination strategies are recommended.

This study aims to evaluate the effectiveness of maternal inactivated COVID-19 vaccination before delivery for infants against Omicron infection in Guangzhou, China. A test-negative case-control design was conducted. This study selected infants born from 1 November 2021 to 23 November 2022 and tested for SARS-CoV-2 between 13 April 2022 and 30 November 2022 during outbreaks in Guangzhou. Multivariable logistic regression was performed to compare the maternal vaccination status of inactivated COVID-19 vaccines before delivery in cases and controls to estimate vaccine effectiveness (VE) for infants within 12 months. According to eligibility criteria, we finally selected 205 test-positive and 114 test-negative infants, as well as their mothers. The effectiveness of inactivated COVID-19 vaccines among fully vaccinated mothers was 48.4% (7.3% to 71.7%) for infants within 12 months, with the effectiveness of partial and booster vaccination showing no significant difference. Effectiveness for full vaccination presented a slight increase according to infants’ age at testing, with 49.6% (−12.3% to 78.4%) for 0–6 months and 59.9% (−0.6% to 84.4%) for over 6 months. A greater protective effect of two-dose vaccination was manifested in infants whose mother had received the second dose during the first trimester (65.9%, 95% CI: 7.7% to 87.9%) of pregnancy rather than preconception (43.5%, 95% CI: −8.7% to 71.1%). Moreover, VE could be improved to 77.1% (11.1% to 95.3%) when mothers received two doses both during pregnancy and 91.8% (41.1% to 99.6%) with receipt of a booster dose during pregnancy. Maternal vaccination with two doses of inactivated COVID-19 vaccines before delivery was moderately effective against Omicron infection in infants during the first 12 months of life. Full vaccination or a booster dose during pregnancy could confer better protection against Omicron for infants, although it might be overestimated due to the insufficient sample size in subgroups.