Department of Clinical Science, Influenza Centre, University of Bergen, Bergen, Norway.
Department of Medicine, Haukeland University Hospital, Bergen, Norway.
Front Public Health. 2023 Jul 21;11:1164326. doi: 10.3389/fpubh.2023.1164326. eCollection 2023.
Preventing infection in healthcare workers (HCWs) is crucial for protecting healthcare systems during the COVID-19 pandemic. Here, we investigated the seroepidemiology of SARS-CoV-2 in HCWs in Norway with low-transmission settings.
From March 2020, we recruited HCWs at four medical centres. We determined infection by SARS-CoV-2 RT-PCR and serological testing and evaluated the association between infection and exposure variables, comparing our findings with global data in a meta-analysis. Anti-spike IgG antibodies were measured after infection and/or vaccination in a longitudinal cohort until June 2021.
We identified a prevalence of 10.5% (95% confidence interval, CI: 8.8-12.3) in 2020 and an incidence rate of 15.0 cases per 100 person-years (95% CI: 12.5-17.8) among 1,214 HCWs with 848 person-years of follow-up time. Following infection, HCWs ( = 63) mounted durable anti-spike IgG antibodies with a half-life of 4.3 months since their seropositivity. HCWs infected with SARS-CoV-2 in 2020 ( = 46) had higher anti-spike IgG titres than naive HCWs ( = 186) throughout the 5 months after vaccination with BNT162b2 and/or ChAdOx1-S COVID-19 vaccines in 2021. In a meta-analysis including 20 studies, the odds ratio (OR) for SARS-CoV-2 seropositivity was significantly higher with household contact (OR 12.6; 95% CI: 4.5-35.1) and occupational exposure (OR 2.2; 95% CI: 1.4-3.2).
We found high and modest risks of SARS-CoV-2 infection with household and occupational exposure, respectively, in HCWs, suggesting the need to strengthen infection prevention strategies within households and medical centres. Infection generated long-lasting antibodies in most HCWs; therefore, we support delaying COVID-19 vaccination in primed HCWs, prioritising the non-infected high-risk HCWs amid vaccine shortage.
在新冠疫情期间，防止医护人员（HCWs）感染对于保护医疗系统至关重要。在这里，我们调查了挪威低传播环境下 HCWs 的 SARS-CoV-2 血清流行病学。
自 2020 年 3 月起，我们在四家医疗中心招募 HCWs。我们通过 SARS-CoV-2 RT-PCR 和血清学检测确定感染情况，并通过荟萃分析评估感染与暴露变量之间的关系，将我们的发现与全球数据进行比较。在 2021 年 6 月之前，对纵向队列中的感染和/或接种疫苗后的抗刺突 IgG 抗体进行了测量。
我们在 1214 名 HCWs 中发现了 10.5%（95%置信区间：8.8-12.3）的患病率和 15.0 例/100 人年（95%置信区间：12.5-17.8）的发病率，随访时间为 848 人年。在感染后，63 名 HCWs 产生了持久的抗刺突 IgG 抗体，自血清阳性以来的半衰期为 4.3 个月。2020 年感染 SARS-CoV-2 的 46 名 HCWs 在 2021 年接种 BNT162b2 和/或 ChAdOx1-S COVID-19 疫苗后的 5 个月内，其抗刺突 IgG 滴度均高于未感染的 HCWs（186 名）。在包括 20 项研究的荟萃分析中，家庭接触（比值比[OR] 12.6；95%置信区间：4.5-35.1）和职业接触（OR 2.2；95%置信区间：1.4-3.2）的 SARS-CoV-2 血清阳性的比值比（OR）显著更高。
我们发现 HCWs 分别因家庭接触和职业接触而感染 SARS-CoV-2 的风险较高和中等，这表明需要加强家庭和医疗中心内的感染预防策略。感染在大多数 HCWs 中产生了持久的抗体；因此，我们支持在疫苗短缺的情况下，在感染高危的 HCWs 中延迟 COVID-19 疫苗接种，优先考虑未感染的高危 HCWs。
