Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.
Illinois Department of Public Health, Chicago, Illinois, USA.
Clin Infect Dis. 2020 Dec 31;71(11):2920-2926. doi: 10.1093/cid/ciaa763.
Outbreaks of coronavirus disease 2019 (COVID-19) have been reported in nursing homes and assisted living facilities; however, the extent of asymptomatic and presymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in this high-risk population remains unclear.
We conducted an investigation of the first known outbreak of SARS-CoV-2 at a skilled nursing facility (SNF) in Illinois on 15 March 2020 and followed residents for 30 days. We tested 126/127 residents for SARS-CoV-2 via reverse-transcription polymerase chain reaction and performed symptom assessments. We calculated the point prevalence of SARS-CoV-2 and assessed symptom onset over 30-day follow-up to determine: (1) the proportion of cases who were symptomatic, presymptomatic, and asymptomatic and (2) incidence of symptoms among those who tested negative. We used the Kaplan-Meier method to determine the 30-day probability of death for cases.
Of 126 residents tested, 33 had confirmed SARS-CoV-2 on 15 March. Nineteen (58%) had symptoms at the time of testing, 1 (3%) developed symptoms over follow-up, and 13 (39%) remained asymptomatic. Thirty-five residents who tested negative on 15 March developed symptoms over follow-up; of these, 3 were re-tested and 2 were positive. The 30-day probability of death among cases was 29%.
SNFs are particularly vulnerable to SARS-CoV-2, and residents are at risk of severe outcomes. Attention must be paid to preventing outbreaks in these and other congregate care settings. Widespread testing and infection control are key to help prevent COVID-19 morbidity and mortality in these high-risk populations.
新冠肺炎（COVID-19）疫情已在疗养院和辅助生活设施中爆发；然而，在这一高风险人群中，无症状和症状前严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染的程度仍不清楚。
我们对 2020 年 3 月 15 日伊利诺伊州一家熟练护理机构（SNF）首例已知的 SARS-CoV-2 暴发进行了调查，并对居民进行了 30 天的随访。我们通过逆转录聚合酶链反应（RT-PCR）对 127 名居民中的 126 名进行了 SARS-CoV-2 检测，并进行了症状评估。我们计算了 SARS-CoV-2 的时点患病率，并评估了 30 天随访期间症状的出现情况，以确定：（1）有症状、症状前和无症状病例的比例；（2）检测阴性者出现症状的发生率。我们使用 Kaplan-Meier 法确定病例的 30 天死亡率。
在 126 名接受检测的居民中，有 33 名于 3 月 15 日确诊为 SARS-CoV-2。19 名（58%）在检测时出现症状，1 名（3%）在随访期间出现症状，13 名（39%）无症状。15 名在 3 月 15 日检测结果为阴性的居民在随访期间出现症状；其中 3 人再次检测结果为阳性，2 人检测结果为阳性。病例的 30 天死亡率为 29%。
SNF 特别容易受到 SARS-CoV-2 的影响，居民面临严重后果的风险。必须注意防止这些和其他集中护理环境中的暴发。广泛的检测和感染控制是帮助预防这些高危人群 COVID-19 发病率和死亡率的关键。
