Department of Epidemiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan.
J Infect Dis. 2024 Sep 23;230(3):662-669. doi: 10.1093/infdis/jiae207.
Understanding the association between the immune response and the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has implications for forthcoming prevention strategies. We evaluated the association between antibody titers and the risk of infection for the general population during the Omicron-dominant phase.
This was a prospective cohort study of residents or people affiliated with institutions in Bizen City, which included 1899 participants. We measured the titers of antibodies against SARS-CoV-2 repeatedly every 2 months from June 2022 to March 2023. Infection status was obtained from self-reported questionnaires and the official registry. We estimated risk ratios (RRs) for infection within 2 months of the date of each antibody measurement with 95% confidence intervals (CIs) based on antibody titer categories and spline functions.
Compared with the <2500 arbitrary unit (AU)/mL category, the 2500-5000, 5000-10 000, and ≥10 000 AU/mL categories had adjusted RRs of 0.81 (95% CI, .61-1.08), 0.51 (95% CI, .36-.72), and 0.41 (95% CI, .31-.54), respectively. The spline function showed a nonlinear relationship between antibody titer and risk.
Higher antibody titers were associated with a lower risk. We demonstrate the usefulness of measuring an antibody titers to determine the appropriate timing for future prevention strategies.
了解免疫反应与严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染风险之间的关系，对即将出台的预防策略具有重要意义。我们评估了在奥密克戎主导阶段，普通人群的抗体滴度与感染风险之间的关系。
这是一项在兵库县美祢市的居民或与该地区机构有关联的人群中开展的前瞻性队列研究，共纳入 1899 名参与者。我们从 2022 年 6 月至 2023 年 3 月每两个月重复测量一次针对 SARS-CoV-2 的抗体滴度。感染状态通过自我报告的问卷和官方登记获得。我们根据抗体滴度类别和样条函数，估计了在每次抗体测量日期后 2 个月内感染的风险比（RR）及其 95%置信区间（CI）。
与<2500 个任意单位（AU）/mL 类别相比，2500-5000、5000-10000 和≥10000 AU/mL 类别的校正 RR 分别为 0.81（95%CI，0.61-1.08）、0.51（95%CI，0.36-0.72）和 0.41（95%CI，0.31-0.54）。样条函数显示抗体滴度与风险之间存在非线性关系。
较高的抗体滴度与较低的风险相关。我们证明了测量抗体滴度来确定未来预防策略的适当时机是有用的。
