Standard tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detect the presence of viral RNA using real-time reverse transcription (rRT)-PCR. Recently, convenient, rapid, and relatively inexpensive SARS-CoV-2 antigen (Ag) detection methods have been developed. The STANDARD Q COVID-19 Ag test (SD Biosensor, Inc., Suwon, Korea) is a rapid immunochromatography test that qualitatively detects the nucleocapsid protein of SARS-CoV-2 using gold conjugated antibodies. We evaluated its performance in comparison with that of Allplex 2019-nCoV Assay (Seegene, Seoul, Korea) in a retrospective case-control study using residual samples. The sensitivity and specificity of the STANDARD Q COVID-19 Ag test were 89.2% (58/65) and 96.0% (96/100), respectively. Cycle threshold (Ct) values for the three target SARS-CoV-2 genes (envelope, RNA-dependent RNA polymerase, and nucleocapsid genes) included in Allplex 2019-nCoV Assay were significantly lower in Ag test-positive patients than in Ag test-negative patients (P<0.001). The Ag test sensitivity was higher in samples with Ct≤30 and those collected one to five days post symptom onset. In conclusion, the STANDARD Q COVID-19 Ag test can serve as an alternative in high-prevalence settings, when the low sensitivity is compensated or when rRT-PCR tests are limited.

中文翻译：

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用于筛查严重急性呼吸系统综合症冠状病毒 2 的快速标准 Q COVID-19 Ag 检测的临床评价。

严重急性呼吸系统综合症冠状病毒 2 (SARS-CoV-2) 的标准测试使用实时逆转录 (rRT)-PCR 检测病毒 RNA 的存在。最近，已经开发了方便、快速且相对便宜的 SARS-CoV-2 抗原 (Ag) 检测方法。STANDARD Q COVID-19 Ag 检测（SD Biosensor, Inc., Suwon, Korea）是一种快速免疫层析检测，可使用金偶联抗体定性检测 SARS-CoV-2 的核衣壳蛋白。我们在使用残留样本的回顾性病例对照研究中评估了其与 Allplex 2019-nCoV 检测（Seegene，首尔，韩国）的性能相比。STANDARD Q COVID-19 Ag 检测的敏感性和特异性分别为 89.2% (58/65) 和 96.0% (96/100)。三个目标 SARS-CoV-2 基因（信封、P <0.001）。在 Ct ≤ 30 的样本和症状出现后 1 到 5 天收集的样本中，Ag 测试的敏感性更高。总之，STANDARD Q COVID-19 Ag 检测可作为高流行率环境中的替代方案，当低灵敏度得到补偿或 rRT-PCR 检测受到限制时。