Universidade Tecnológica Federal do Paraná, Dois Vizinhos, PR, Brazil.
Universidade Tecnológica Federal do Paraná, Dois Vizinhos, PR, Brazil.
J Virol Methods. 2022 Feb;300:114429. doi: 10.1016/j.jviromet.2021.114429. Epub 2021 Dec 14.
The rapid spread of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has led the world to a pandemic. Therefore, rapid, sensitive, and reproducible diagnostic tests are essential to indicate which measures should be taken during pandemics. We retrospectively tested unextracted nasopharyngeal samples from consecutive patients with suspected SARS-CoV-2 infection (n = 334), and compared two different Ct cut-off values for interpretation of results using a modified Allplex protocol. Its performance was evaluated using the USA Centers for Disease Control and Prevention (CDC) as reference. The reduction on Ct cut-off to 35 increased the test NPA from 79.65 to 88.00 %, reducing the number of false positives, from 10.48 to 6.29 %, resulting in an almost perfect agreement between the Allplex and the CDC protocol (Cohen's Kappa coefficient = 0.830 ± 0.032). This study demonstrates that the Seegene Allplex™ 2019-nCoV protocol skipping the viral RNA extraction step using the Ct cut-off of 35 is a rapid and efficient method to detect SARS-CoV-2 in nasopharyngeal samples.
严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 的迅速传播使世界陷入大流行。因此，快速、敏感和可重复的诊断测试对于指示大流行期间应采取哪些措施至关重要。我们回顾性地检测了连续疑似 SARS-CoV-2 感染患者的未经提取的鼻咽样本(n = 334)，并使用改良的 Allplex 方案比较了两种不同的 Ct 截止值用于解释结果。其性能使用美国疾病控制与预防中心 (CDC) 作为参考进行评估。将 Ct 截止值降低到 35 可将测试 NPA 从 79.65%提高到 88.00%，同时减少假阳性数量，从 10.48%降至 6.29%，从而使 Allplex 和 CDC 方案之间几乎完全一致 (Cohen 的 Kappa 系数= 0.830 ± 0.032)。这项研究表明，跳过病毒 RNA 提取步骤并使用 35 的 Ct 截止值的 Seegene Allplex™ 2019-nCoV 方案是一种快速有效的方法，可用于检测鼻咽样本中的 SARS-CoV-2。
