The purpose of this study was to detect coronavirus disease 2019 (COVID-19) cases with persistent positive reverse transcription-PCR (RT-PCR) results for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), for which viable virus can be inferred due to the presence of subgenomic (SG) viral RNA, which is expressed only in replicating viruses. RNA remnants purified from diagnostic nasopharyngeal specimens were used as the templates for RT-PCR-specific detection of SG E gene RNA. As controls, we also detected viral genomic RNA for the E gene and/or a human housekeeping gene (RNase P). We assessed the samples of 60 RT-PCR-positive cases with prolonged viral SARS-CoV-2 shedding (24 to 101 days) since the first diagnostic RT-PCR. SG viral RNA was detected in 12/60 (20%) of the persistent cases, 28 to 79 days after the onset of symptoms. The age range of the cases with prolonged viral shedding and the presence of SG RNA was quite wide (40 to 100 years), and the cases were equally distributed between males (42%) and females (58%). No case was HIV positive, although seven were immunosuppressed. According to the severities of the COVID-19 episodes, they were mild (40%), intermediate (20%), and severe (40%). In a percentage of persistent SARS-CoV-2 PCR-positive cases, the presence of actively replicating virus may be inferred, far beyond diagnosis. We should not assume a universal lack of infectiousness for COVID-19 cases with prolonged viral shedding.

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SARS-CoV-2持续阳性逆转录-PCR结果阳性病毒复制的推论

这项研究的目的是通过重症急性呼吸综合征冠状病毒2（SARS-CoV-2）的持续反转录PCR（RT-PCR）结果检测冠状病毒病2019（COVID-19）病例，对此病毒可以由于存在仅在复制型病毒中表达的亚基因组（SG）病毒RNA，因此可以推断出这种情况。从诊断性鼻咽标本中纯化的RNA残留物用作RT-PCR特异性检测SG E基因RNA的模板。作为对照，我们还检测了E基因和/或人类管家基因（RNase P）的病毒基因组RNA。自首次诊断性RT-PCR以来，我们评估了60例病毒SARS-CoV-2脱落时间延长（24至101天）的RT-PCR阳性病例的样品。症状发作后28至79天，在12/60（20％）的持续病例中检测到SG病毒RNA。病毒脱落时间较长且存在SG RNA的病例年龄范围很广（40至100岁），且病例平均分布在男性（42％）和女性（58％）之间。尽管有7例免疫抑制，但没有HIV阳性病例。根据COVID-19发作的严重程度，轻度（40％），中度（20％）和重度（40％）。在一定比例的持续性SARS-CoV-2 PCR阳性病例中，可以推断出存在主动复制的病毒，这远远超出了诊断范围。对于COVID-19病毒脱落时间长的病例，我们不应该普遍缺乏传染性。尽管有七个被免疫抑制。根据COVID-19发作的严重程度，轻度（40％），中度（20％）和重度（40％）。在一定比例的持续性SARS-CoV-2 PCR阳性病例中，可以推断出存在主动复制的病毒，这远远超出了诊断范围。对于COVID-19病毒脱落时间长的病例，我们不应该普遍缺乏传染性。尽管有七个被免疫抑制。根据COVID-19发作的严重程度，轻度（40％），中度（20％）和重度（40％）。在一定比例的持续性SARS-CoV-2 PCR阳性病例中，可以推断出存在主动复制的病毒，这远远超出了诊断范围。对于COVID-19病毒脱落时间长的病例，我们不应该普遍缺乏传染性。