Infection Control Team, Korea University Guro Hospital, Seoul, Korea.
Division of Infectious Disease, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
J Korean Med Sci. 2022 Sep 5;37(35):e267. doi: 10.3346/jkms.2022.37.e267.
The omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to have high infectivity and is more likely to evade vaccine immunity. However, booster vaccination is expected to strengthen cross-reactive immunity, thereby increasing the vaccine effectiveness (VE). This study aimed to evaluate the relative VE of the 3-dose (booster) vaccination compared with the 2-dose primary series vaccination in healthcare workers during omicron variant-dominant periods. During the omicron-dominant period from February 1, 2022 to February 28, 2022, a 1:1 matched case-control study was conducted. Healthcare workers with positive SARS-CoV-2 test results were classified as positive cases, whereas those with negative results served as controls. Compared with the 2-dose primary series vaccination, booster vaccination with mRNA vaccine showed moderate VE (53.1%). However, in multivariate analysis including the time elapsed after vaccination, the significant VE disappeared, reflecting the impact of recent vaccination rather than the third dose itself.
奥密克戎变异株严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）具有高传染性，且更有可能逃避疫苗免疫。然而，加强针接种有望增强交叉反应性免疫，从而提高疫苗有效性（VE）。本研究旨在评估在奥密克戎变异株流行期间，与 2 剂基础系列疫苗相比，3 剂（加强针）疫苗接种在医护人员中的相对 VE。在 2022 年 2 月 1 日至 2022 年 2 月 28 日奥密克戎流行期间，进行了 1:1 匹配的病例对照研究。SARS-CoV-2 检测结果阳性的医护人员被归类为阳性病例，而检测结果阴性的医护人员则作为对照。与 2 剂基础系列疫苗相比，mRNA 疫苗的加强针接种显示出中等 VE（53.1%）。然而，在包括接种后时间的多变量分析中，显著的 VE 消失了，这反映了最近接种的影响，而不是第三剂本身。
