Kim Geehyuk, Kang Jun-Kyu, Kim Jungho, Lee Jiyoung, Gwack Jin
Central Disease Control Headquarters, Korea Disease Control and Prevention Agency, Cheongju, Korea.
Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Korea.
Osong Public Health Res Perspect. 2022 Aug;13(4):252-262. doi: 10.24171/j.phrp.2022.0135. Epub 2022 Jul 27.
Real-time polymerase chain reaction is currently used as a confirmatory test for coronavirus disease 2019 (COVID-19). The test results are interpreted as positive, negative, or inconclusive, and are used only for a qualitative classification of patients. However, the test results can be quantitated using threshold count (Ct) values to determine the amount of virus present in the sample. Therefore, this study investigated the diagnostic usefulness of Ct results through various quantitative analyzes, along with an analysis of clinical and epidemiological characteristics.
Clinical and epidemiological data from 4,642 COVID-19 patients in April 2021 were analyzed, including the Ct values of the RNA-dependent RNA polymerase (RdRp), envelope (E), and nucleocapsid (N) genes. Clinical and epidemiological data (sex, age, underlying diseases, and early symptoms) were collected through a structured questionnaire. A correlation analysis was used to examine the relationships between variables.
All 3 genes showed statistically significant relationships with symptoms and severity levels. The Ct values of the RdRp gene decreased as the severity of the patients increased. Moreover, statistical significance was observed for the presence of underlying diseases and dyspnea.
Ct values were found to be related to patients' clinical and epidemiological characteristics. In particular, since these factors are closely related to symptoms and severity, Ct values can be used as primary data for predicting patients' disease prognosis despite the limitations of this method. Conducting follow-up studies to validate this approach might enable using the data from this study to establish policies for preventing COVID-19 infection and spread.
实时聚合酶链反应目前用作2019冠状病毒病（COVID-19）的确证检测。检测结果被解释为阳性、阴性或不确定，且仅用于对患者进行定性分类。然而，检测结果可使用阈值计数（Ct）值进行定量，以确定样本中存在的病毒量。因此，本研究通过各种定量分析以及对临床和流行病学特征的分析，调查了Ct结果的诊断效用。
分析了2021年4月4642例COVID-19患者的临床和流行病学数据，包括RNA依赖性RNA聚合酶（RdRp）、包膜（E）和核衣壳（N）基因的Ct值。通过结构化问卷收集临床和流行病学数据（性别、年龄、基础疾病和早期症状）。采用相关性分析来检验变量之间的关系。
所有3个基因均与症状和严重程度水平存在统计学显著关系。随着患者病情严重程度增加，RdRp基因的Ct值降低。此外，基础疾病的存在和呼吸困难具有统计学显著性。
发现Ct值与患者的临床和流行病学特征相关。特别是，由于这些因素与症状和严重程度密切相关，尽管该方法存在局限性，但Ct值可作为预测患者疾病预后的主要数据。开展后续研究以验证该方法可能有助于利用本研究的数据制定预防COVID-19感染和传播的政策。
