Lake Central School Corporation, Saint John, IN, United States of America.
City of Evanston, Evanston, IL, United States of America.
PLoS One. 2021 Jun 10;16(6):e0243676. doi: 10.1371/journal.pone.0243676. eCollection 2021.
Since March 2020, the United States has lost over 580,000 lives to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19. A growing body of literature describes population-level SARS-CoV-2 exposure, but studies of antibody seroprevalence within school systems are critically lacking, hampering evidence-based discussions on school reopenings. The Lake Central School Corporation (LCSC), a public school system in suburban Indiana, USA, assessed SARS-CoV-2 seroprevalence in its staff and identified correlations between seropositivity and subjective histories and demographics. This study is a cross-sectional, population-based analysis of the seroprevalence of SARS-CoV-2 in LCSC staff measured in July 2020. We tested for seroprevalence with the Abbott Alinity™ SARS-CoV-2 IgG antibody test. The primary outcome was the total seroprevalence of SARS-CoV-2, and secondary outcomes included trends of antibody presence in relation to baseline attributes. 753 participants representative of the staff at large were enrolled. 22 participants (2.9%, 95% CI: 1.8% - 4.4%) tested positive for SARS-CoV-2 antibodies. Correcting for test performance parameters, the seroprevalence is estimated at 1.7% (90% Credible Interval: 0.27% - 3.3%). Multivariable logistic regression including mask wearing, travel history, symptom history, and contact history revealed a 48-fold increase in the odds of seropositivity if an individual previously tested positive for COVID-19 (OR: 48, 95% CI: 4-600). Amongst individuals with no previous positive test, exposure to a person diagnosed with COVID-19 increased the odds of seropositivity by 7-fold (OR: 7.2, 95% CI: 2.6-19). Assuming the presence of antibodies is associated with immunity against SARS-CoV-2 infection, these results demonstrate a broad lack of herd immunity amongst the school corporation's staff irrespective of employment role or location. Protective measures like contact tracing, face coverings, and social distancing are therefore vital to maintaining the safety of both students and staff as the school year progresses.
自 2020 年 3 月以来，美国已有超过 58 万人死于严重急性呼吸系统综合症冠状病毒 2（SARS-CoV-2），该病毒引发了 COVID-19。越来越多的文献描述了人群层面的 SARS-CoV-2 暴露情况，但在学校系统内进行的抗体血清阳性率研究却严重缺乏，这阻碍了基于证据的学校重新开放讨论。美国印第安纳州郊区的湖中央学区（LCSC）评估了其员工中的 SARS-CoV-2 血清阳性率，并确定了血清阳性率与主观病史和人口统计学之间的相关性。本研究是对 LCSC 员工中 SARS-CoV-2 血清阳性率的横断面、基于人群的分析，于 2020 年 7 月进行。我们使用 Abbott Alinity™ SARS-CoV-2 IgG 抗体检测试剂盒进行血清阳性率检测。主要结局是 SARS-CoV-2 的总血清阳性率，次要结局包括与基线属性相关的抗体存在趋势。共有 753 名具有代表性的员工参加了研究。22 名参与者（2.9%，95%置信区间：1.8% - 4.4%）的 SARS-CoV-2 抗体检测呈阳性。根据检测性能参数校正后，血清阳性率估计为 1.7%（90%可信区间：0.27% - 3.3%）。包括戴口罩、旅行史、症状史和接触史在内的多变量逻辑回归显示，如果个体之前 COVID-19 检测呈阳性，则血清阳性的几率增加 48 倍（OR：48，95%CI：4-600）。在没有先前阳性检测结果的个体中，与确诊 COVID-19 的人接触使血清阳性的几率增加了 7 倍（OR：7.2，95%CI：2.6-19）。假设存在抗体与对 SARS-CoV-2 感染的免疫力相关，这些结果表明，无论员工的角色或工作地点如何，学校公司员工的群体免疫力都普遍缺乏。因此，在学年进行过程中，接触者追踪、口罩和社交距离等保护措施对于维护学生和员工的安全至关重要。
