People suffering from COVID-19 are typically considered non-infectious 14 days after diagnosis if symptoms have disappeared for at least 48 h. We describe three patients who independently acquired their infection. These three patients experienced mild COVID-19 and completely recovered symptomatically within 10 days, but remained PCR-positive in deep pharyngeal samples for at least 38 days. We attempted to isolate virus from pharyngeal swabs to investigate whether these patients still carried infectious virus.

中文翻译：

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感染性 SARS-CoV-2 颗粒在轻度 COVID-19 患者中持续存在长达 37 天

如果症状消失至少 48 小时，则患有 COVID-19 的人通常在诊断后 14 天被认为没有传染性。我们描述了三名独立获得感染的患者。这三名患者经历了轻度 COVID-19，并在 10 天内完全康复，但在深部咽部样本中 PCR 阳性至少 38 天。我们试图从咽拭子中分离病毒，以调查这些患者是否仍然携带传染性病毒。