Objective To determine clinical and ethnodemographic correlates of serological responses against the SARS-CoV-2 spike glycoprotein following mild-to-moderate COVID-19. Design A retrospective cohort study of healthcare workers who had self-isolated due to COVID-19. Setting University Hospitals Birmingham NHS Foundation Trust, UK (UHBFT). Participants 956 healthcare workers were recruited by open invitation via UHBFT trust email and social media between 27 April 2020 and the 8 June 2020. Intervention Participants volunteered a venous blood sample that was tested for the presence of anti-SARS-CoV-2 spike glycoprotein antibodies. Results were interpreted in the context of the symptoms of their original illness and ethnodemographic variables. Results Using an assay that simultaneously measures the combined IgG, IgA and IgM response against the spike glycoprotein (IgGAM), the overall seroprevalence within this cohort was 46.2% (n=442/956). The seroprevalence of immunoglobulin isotypes was 36.3%, 18.7% and 8.1% for IgG, IgA and IgM, respectively. IgGAM identified serological responses in 40.6% (n=52/128) of symptomatic individuals who reported a negative SARS-CoV-2 PCR test. Increasing age, non-white ethnicity and obesity were independently associated with greater IgG antibody response against the spike glycoprotein. Self-reported fever and fatigue were associated with greater IgG and IgA responses against the spike glycoprotein. The combination of fever and/or cough and/or anosmia had a positive predictive value of 92.3% for seropositivity in self-isolating individuals a time when Wuhan strain SARS-CoV-2 was predominant. Conclusions and relevance Assays employing combined antibody detection demonstrate enhanced seroepidemiological sensitivity and can detect prior viral exposure even when PCR swabs have been negative. We demonstrate an association between known ethnodemographic risk factors associated with mortality from COVID-19 and the magnitude of serological responses in mild-to-moderate disease. Data are available on reasonable request.

中文翻译：

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非住院感染后对 SARS-CoV-2 的血清学反应：与抗体反应强度相关的临床和民族特征

目的 确定轻至中度 COVID-19 后针对 SARS-CoV-2 刺突糖蛋白的血清学反应的临床和民族统计学相关性。设计对因 COVID-19 进行自我隔离的医护人员进行回顾性队列研究。设置英国伯明翰 NHS 基金会信托大学医院 (UHBFT)。参与者 2020 年 4 月 27 日至 2020 年 6 月 8 日期间，通过 UHBFT 信托电子邮件和社交媒体公开邀请招募了 956 名医护人员。干预参与者自愿提供静脉血样本，检测是否存在抗 SARS-CoV-2 刺突糖蛋白抗体。结果是根据其原始疾病的症状和民族人口学变量来解释的。结果 使用同时测量针对刺突糖蛋白 (IgGAM) 的 IgG、IgA 和 IgM 联合反应的检测，该队列中的总体血清阳性率为 46.2% (n=442/956)。免疫球蛋白同种型的血清阳性率分别为 IgG、IgA 和 IgM 的 36.3%、18.7% 和 8.1%。IgGAM 在 40.6% (n=52/128) 报告 SARS-CoV-2 PCR 检测阴性的有症状个体中发现了血清学反应。年龄增长、非白人种族和肥胖与针对刺突糖蛋白的 IgG 抗体反应增强独立相关。自我报告的发烧和疲劳与针对刺突糖蛋白的 IgG 和 IgA 反应增强相关。当武汉毒株 SARS-CoV-2 占主导地位时，发烧和/或咳嗽和/或嗅觉缺失的组合对自我隔离个体的血清阳性预测值为 92.3%。结论和相关性 采用组合抗体检测的检测方法显示血清流行病学敏感性增强，即使 PCR 拭子呈阴性，也能检测到先前的病毒暴露情况。我们证明了与 COVID-19 死亡率相关的已知民族人口学危险因素与轻至中度疾病的血清学反应程度之间的关联。可根据合理要求提供数据。