Medical Scientist Training Program / Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States of America.
Stead Family Department of Pediatrics/ Division of Medical Genetics and Genomic / Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States of America.
PeerJ. 2022 May 10;10:e13277. doi: 10.7717/peerj.13277. eCollection 2022.
The rise of novel, more infectious SARS-CoV-2 variants has made clear the need to rapidly deploy large-scale testing for COVID-19 to protect public health. However, testing remains limited due to shortages of personal protective equipment (PPE), naso- and oropharyngeal swabs, and healthcare workers. Simple test methods are needed to enhance COVID-19 screening. Here, we describe a simple, and inexpensive spit-test for COVID-19 screening called Patient Self-Collection of Sample-CoV2 ().
To evaluate an affordable and convenient test for COVID-19.
The collection method relies on deep throat sputum (DTS) self-collected by the subject without the use of swabs, and was hence termed the Self-Collection of Sample for SARS-CoV-2 (abbreviated ). We used a phenol-chloroform extraction method for the viral RNA. We then tested for SARS-CoV-2 using real-time reverse transcription polymerase chain reaction with primers against at least two coding regions of the viral nucleocapsid protein (N1 and N2 or E) of SARS-CoV-2. We evaluted the sensitivity and specificity of our protocol. In addition we assess the limit of detection, and efficacy of our Viral Inactivating Solution. We also evaluated our protocol, and pooling strategy from volunteers on a local college campus.
We show that the method accurately identified 42 confirmed COVID-19 positives, which were confirmed through the nasopharyngeal swabbing method of an FDA approved testing facility. For samples negative for COVID-19, we show that the cycle threshold for N1, N2, and RP are similar between the and nasopharynx swab collection method ( = 30). We found a sensitivity of 100% (95% Confidence Interval [CI], 92-100) and specifity of 100% (95% CI, 89-100) for our method. We determined our protocol has a limit of detection of 1/10,000 for DTS from a COVID-19 patient. In addition, we show field data of the method on a college campus. Ten of the twelve volunteers (N1 < 30) that we tested as positive were subsequently tested positive by an independent laboratory. Finally, we show proof of concept of a pooling strategy to test for COVID-19, and recommend pool sizes of four if the positivity rate is less than 15%.
We developed a DTS-based protocol for COVID-19 testing with high sensitivity and specificity. This protocol can be used by non-debilitated adults without the assistance of another adult, or by non-debilitated children with the assistance of a parent or guardian. We also discuss pooling strategies based on estimated positivity rates to help conserve resources, time, and increase throughput. The method can be a key component of community-wide efforts to slow the spread of COVID-19.
新型、更具传染性的 SARS-CoV-2 变体的出现，清楚地表明需要迅速大规模开展 COVID-19 检测，以保护公众健康。然而，由于个人防护设备 (PPE)、鼻咽和口咽拭子以及医护人员的短缺，检测仍然受到限制。需要简单的测试方法来增强 COVID-19 筛查。在这里，我们描述了一种简单且廉价的 COVID-19 筛查唾液测试，称为患者自身采集样本用于检测 SARS-CoV-2（简称 ）。
评估一种负担得起且方便的 COVID-19 检测方法。
采集方法依赖于受检者自行采集的深喉痰（DTS），无需使用拭子，因此称为 SARS-CoV-2 自身采集样本（简称 ）。我们使用苯酚-氯仿提取法提取病毒 RNA。然后，我们使用针对 SARS-CoV-2 病毒核衣壳蛋白（N1 和 N2 或 E）至少两个编码区域的实时逆转录聚合酶链反应检测 SARS-CoV-2。我们评估了我们方案的敏感性和特异性。此外，我们评估了我们的病毒灭活溶液的检测限和功效。我们还评估了我们的方案以及当地大学校园志愿者的汇集策略。
我们表明，该 方法准确地识别了 42 例经 FDA 批准的检测机构鼻咽拭子检测确认为 COVID-19 阳性的病例。对于 COVID-19 阴性样本，我们表明，N1、N2 和 RP 的循环阈值在 方法和鼻咽拭子采集方法之间相似（=30）。我们发现，我们的 方法的敏感性为 100%（95%置信区间[CI]，92-100），特异性为 100%（95%CI，89-100）。我们确定我们的方案对 COVID-19 患者的 DTS 检测限为 1/10000。此外，我们展示了大学校园上的 方法的现场数据。我们测试的 12 名志愿者中有 10 名（N1<30）被检测为阳性，随后被独立实验室检测为阳性。最后，我们展示了一种用于 COVID-19 检测的汇集策略的概念验证，并建议在阳性率低于 15%的情况下，每个汇集组包含 4 个样本。
我们开发了一种基于 DTS 的 COVID-19 检测方案，具有高灵敏度和特异性。该方案可用于无残疾的成年人，无需其他成年人的协助，也可用于无残疾的儿童，在父母或监护人的协助下进行。我们还讨论了基于估计阳性率的汇集策略，以帮助节约资源、时间并提高吞吐量。 方法可以成为社区范围内减缓 COVID-19 传播的关键组成部分。
