To inform public health policy, it is critical to monitor COVID-19 vaccine effectiveness (VE), including against acquiring infection. We estimated VE using self-reported vaccination in a retrospective cohort of repeat blood donors who donated during the first half of 2021, demonstrating a viable approach for monitoring of VE via serological surveillance. Using Poisson regression, we estimated an overall VE of 88.8% (95% CI: 86.2–91.1), adjusted for demographic covariates and variable baseline risk. Time since first reporting vaccination, age, race-ethnicity, region, and calendar time were statistically significant predictors of incident infection.

中文翻译：

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在 Delta 和 Omicron 相关激增之前，美国 COVID-19 疫苗对 SARS-CoV-2 感染的有效性：重复献血者的回顾性队列研究

为告知公共卫生政策，监测 COVID-19 疫苗有效性 (VE) 至关重要，包括防止感染。我们在 2021 年上半年献血的重复献血者的回顾性队列中使用自我报告的疫苗接种估计 VE，证明了通过血清学监测监测 VE 的可行方法。使用泊松回归，我们估计总体 VE 为 88.8%（95% CI：86.2–91.1），并针对人口统计学协变量和可变基线风险进行了调整。自首次报告接种疫苗以来的时间、年龄、种族、地区和日历时间是事件感染的具有统计学意义的预测因素。