The Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA.
Vaccine and Infectious Disease Division, Fred Hutchinson, Cancer Research Center, Seattle, Washington, USA.
J Infect Dis. 2022 Sep 13;226(5):788-796. doi: 10.1093/infdis/jiac048.
While detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by diagnostic reverse-transcription polymerase chain reaction (RT-PCR) is highly sensitive for viral RNA, the nucleic acid amplification of subgenomic RNAs (sgRNAs) that are the product of viral replication may more accurately identify replication. We characterized the diagnostic RNA and sgRNA detection by RT-PCR from nasal swab samples collected daily by participants in postexposure prophylaxis or treatment studies for SARS-CoV-2. Among 1932 RT-PCR-positive swab samples with sgRNA tests, 40% (767) had detectable sgRNA. Above a diagnostic RNA viral load (VL) threshold of 5.1 log10 copies/mL, 96% of samples had detectable sgRNA with VLs that followed a linear trend. The trajectories of diagnostic RNA and sgRNA VLs differed, with 80% peaking on the same day but duration of sgRNA detection being shorter (8 vs 14 days). With a large sample of daily swab samples we provide comparative sgRNA kinetics and a diagnostic RNA threshold that correlates with replicating virus independent of symptoms or duration of illness.
虽然诊断性逆转录聚合酶链反应（RT-PCR）检测严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）对病毒 RNA 具有高度敏感性，但亚基因组 RNA（sgRNA）的核酸扩增是病毒复制的产物，可能更准确地识别复制。我们对接受 SARS-CoV-2 暴露后预防或治疗研究的参与者每日采集的鼻拭子样本中通过 RT-PCR 检测的诊断性 RNA 和 sgRNA 进行了特征描述。在 1932 份 RT-PCR 阳性拭子样本中进行了 sgRNA 检测，其中 40%（767 份）可检测到 sgRNA。在诊断性 RNA 病毒载量（VL）阈值为 5.1 log10 拷贝/mL 以上时，96%的样本可检测到 sgRNA，其 VL 呈线性趋势。诊断性 RNA 和 sgRNA VL 的轨迹不同，80%的样本在同一天达到峰值，但 sgRNA 的检测持续时间更短（8 天 vs. 14 天）。通过对大量每日拭子样本的分析，我们提供了比较 sgRNA 动力学和与症状或疾病持续时间无关的与复制病毒相关的诊断性 RNA 阈值。
