Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana.
Lilly UK, Windlesham, Surrey, UK.
J Med Virol. 2020 Nov;92(11):2874-2879. doi: 10.1002/jmv.26182. Epub 2020 Jul 2.
The Asymptomatic novel CORonavirus iNfection (ACORN) study was designed to investigate the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the asymptomatic adult population of the Indianapolis metropolitan area, to follow individuals testing positive for the development of symptoms, and to understand duration of positive test results. ACORN is a cross-sectional community-based observational study of adult residents presenting asymptomatic for COVID-like illness, defined as the self-reported absence of the following three symptoms in the last 7 days: fever (≥100°F), new-onset or worsening cough, and new-onset or worsening shortness of breath. SARS-CoV-2 infection was determined by real-time reverse transcription-polymerase chain reaction in nasopharyngeal swab samples. SARS-CoV-2 infection prevalence was expressed as a point estimate with 95% confidence interval (CI). Test results are reported for 2953 participants who enrolled and underwent nasopharyngeal swab testing between 7 April 2020 and 16 May 2020. Among tested participants, 91 (3.1%; 95% CI: 2.5%-3.7%) were positive for SARS-CoV-2. Overall, baseline characteristics, medical history, and infection risk factors were comparable between SARS-CoV-2 positive and negative participants. Within the ongoing 14-day follow-up period for positive participants, 58 (71.6%) of 81 assessed participants remained asymptomatic while others (n = 23, 28.4%) reported one or more symptoms. Indiana had "Stay-at-Home" orders in place during nearly the entire test period reported here, yet 3.1% of asymptomatic participants tested positive for SARS-CoV-2. These results indicate screening questions had limited predictive utility for testing in an asymptomatic population and suggest broader testing strategies are needed. Importantly, these findings underscore that more research is needed to understand the viral transmission and the role asymptomatic and presymptomatic individuals play in this global pandemic.
无症状新型冠状病毒感染（ACORN）研究旨在调查印第安纳波利斯大都市区无症状成年人群中严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染的流行率，对检测呈阳性的个体进行随访，以了解阳性检测结果的持续时间。ACORN 是一项针对无症状出现 COVID 样疾病的成年居民的横断面社区观察性研究，无症状定义为过去 7 天内未报告以下三种症状：发热（≥100°F）、新发或加重咳嗽、新发或加重呼吸急促。通过鼻咽拭子样本中的实时逆转录-聚合酶链反应确定 SARS-CoV-2 感染。SARS-CoV-2 感染率以 95%置信区间（CI）的点估计表示。报告了 2953 名参与者的检测结果，他们于 2020 年 4 月 7 日至 5 月 16 日期间参加并接受了鼻咽拭子检测。在接受检测的参与者中，91 人（3.1%；95%CI：2.5%-3.7%）SARS-CoV-2 检测呈阳性。总体而言，SARS-CoV-2 阳性和阴性参与者的基线特征、病史和感染危险因素相似。在阳性参与者的 14 天持续随访期间，81 名评估参与者中有 58 名（71.6%）仍无症状，而其他参与者（n=23，28.4%）报告了一种或多种症状。印第安纳州在报告的大部分测试期间都有“就地避难”命令，但仍有 3.1%的无症状参与者检测出 SARS-CoV-2 呈阳性。这些结果表明，筛查问题对无症状人群的检测预测能力有限，表明需要更广泛的检测策略。重要的是，这些发现突显出，需要更多的研究来了解病毒传播以及无症状和症状前个体在这场全球大流行中的作用。
