Clinical Immunology Service, University of Birmingham College of Medical and Dental Sciences, Birmingham, UK.
University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.
Thorax. 2020 Dec;75(12):1089-1094. doi: 10.1136/thoraxjnl-2020-215414. Epub 2020 Sep 11.
To determine the rates of asymptomatic viral carriage and seroprevalence of SARS-CoV-2 antibodies in healthcare workers.
A cross-sectional study of asymptomatic healthcare workers undertaken on 24/25 April 2020.
University Hospitals Birmingham NHS Foundation Trust (UHBFT), UK.
545 asymptomatic healthcare workers were recruited while at work. Participants were invited to participate via the UHBFT social media. Exclusion criteria included current symptoms consistent with COVID-19. No potential participants were excluded.
Participants volunteered a nasopharyngeal swab and a venous blood sample that were tested for SARS-CoV-2 RNA and anti-SARS-CoV-2 spike glycoprotein antibodies, respectively. Results were interpreted in the context of prior illnesses and the hospital departments in which participants worked.
Proportion of participants demonstrating infection and positive SARS-CoV-2 serology.
The point prevalence of SARS-CoV-2 viral carriage was 2.4% (n=13/545). The overall seroprevalence of SARS-CoV-2 antibodies was 24.4% (n=126/516). Participants who reported prior symptomatic illness had higher seroprevalence (37.5% vs 17.1%, χ=21.1034, p<0.0001) and quantitatively greater antibody responses than those who had remained asymptomatic. Seroprevalence was greatest among those working in housekeeping (34.5%), acute medicine (33.3%) and general internal medicine (30.3%), with lower rates observed in participants working in intensive care (14.8%). BAME (Black, Asian and minority ethnic) ethnicity was associated with a significantly increased risk of seropositivity (OR: 1.92, 95% CI 1.14 to 3.23, p=0.01). Working on the intensive care unit was associated with a significantly lower risk of seropositivity compared with working in other areas of the hospital (OR: 0.28, 95% CI 0.09 to 0.78, p=0.02).
We identify differences in the occupational risk of exposure to SARS-CoV-2 between hospital departments and confirm asymptomatic seroconversion occurs in healthcare workers. Further investigation of these observations is required to inform future infection control and occupational health practices.
确定无症状病毒携带率和 SARS-CoV-2 抗体血清阳性率在医护人员中的情况。
2020 年 4 月 24 日至 25 日对无症状医护人员进行的横断面研究。
英国伯明翰大学医院 NHS 基金会信托（UHBFT）。
在工作时招募了 545 名无症状医护人员。UHBFT 通过社交媒体邀请参与者参加。排除标准包括与 COVID-19 一致的当前症状。没有排除任何潜在的参与者。
参与者自愿提供鼻咽拭子和静脉血样，分别用于检测 SARS-CoV-2 RNA 和抗 SARS-CoV-2 刺突糖蛋白抗体。结果根据既往疾病和参与者工作的医院科室进行解释。
表现出感染和 SARS-CoV-2 血清学阳性的参与者比例。
SARS-CoV-2 病毒携带的时点患病率为 2.4%（n=13/545）。SARS-CoV-2 抗体的总血清阳性率为 24.4%（n=126/516）。报告有既往症状性疾病的参与者的血清阳性率更高（37.5% vs 17.1%，χ=21.1034，p<0.0001），抗体反应也更强。在从事家政服务（34.5%）、急性医学（33.3%）和普通内科（30.3%）的参与者中，血清阳性率最高，而在重症监护病房工作的参与者中则较低（14.8%）。BAME（黑人、亚洲人和少数民族）种族与血清阳性率显著升高相关（OR：1.92，95%CI 1.14 至 3.23，p=0.01）。与在医院其他科室工作相比，在重症监护病房工作与血清阳性率显著降低相关（OR：0.28，95%CI 0.09 至 0.78，p=0.02）。
我们发现医院科室之间 SARS-CoV-2 暴露的职业风险存在差异，并证实无症状血清转化率发生在医护人员中。需要进一步调查这些观察结果，以为未来的感染控制和职业健康实践提供信息。
