Annual Variant-Targeted Vaccination to Prevent Severe COVID-19 in Cohorts With Vaccine-Derived and Hybrid Immunity

作者：J. Daniel Kelly, Katherine J. Hoggatt, Nathan C. Lo, Samuel Leonard, W. John Boscardin, Hye Sun Kim, Emily N. Lum, Charles Austin, Amy L. Byers, Phyllis C. Tien, Peter C. Austin, Dawn M. Bravata, Salomeh Keyhani · 发表于：Clinical Infectious Diseases · 年份：2025 · DOI：10.1093/cid/ciaf124 · 被引用次数：8 · 研究领域：SARS-CoV-2 and COVID-19 Research、Immune responses and vaccinations、Vaccine Coverage and Hesitancy

BACKGROUND: Current coronavirus disease 2019 (COVID-19) vaccine recommendations in the United States (US) provide guidance for adults to receive at least annual variant-targeted vaccination. We sought to estimate the strength and durability of protection from annual variant-targeted vaccination against severe COVID-19 illness in individuals with vaccine-derived and hybrid immunity. METHODS: We emulated a target trial using an electronic health record-based, propensity score-matched (1:1) cohort of US Veterans. Booster-vaccinated adults were eligible for a variant-targeted messenger RNA (mRNA) booster starting 1 September 2022. Matched sets of those who did and did not receive the variant-targeted booster dose were identified on a weekly basis, and the cohort was followed until 31 August 2023. Outcomes were hospitalization due to COVID-19 pneumonia and in-hospital severe illness. We fit Cox models, overall and stratified by last documented severe acute respiratory syndrome coronavirus 2 infection (pre-Omicron, Omicron), to estimate relative vaccine effectiveness (rVE). RESULTS: The propensity score-matched cohort consisted of 1 576 626 COVID-19 booster-vaccinated adults. Estimates of rVE from variant-targeted mRNA booster against hospitalization due to COVID-19 pneumonia were significant and similar in the cohort with vaccine-derived immunity (rVE, 29% [95% confidence interval {CI}, 25%-34%]) and cohort with hybrid immunity (rVE, 38% [95% CI, 27%-47%]). These protective gains ...