Laboratory of Molecular Biology/Virology, Clinical Pathology Unit, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
Molecular Hematology Laboratory, Department of Clinical Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
J Med Virol. 2020 Oct;92(10):2227-2231. doi: 10.1002/jmv.26103. Epub 2020 Jun 19.
Patients with coronavirus disease-2019 may be discharged based on clinical resolution of symptoms, and evidence for viral RNA clearance from the upper respiratory tract. Understanding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral clearance profile is crucial to establish a re-testing plan on discharge and ending isolation of patients. We aimed to evaluate the number of days that a patient needed to achieve undetectable levels of SARS-CoV-2 in upper respiratory tract specimens (nasopharyngeal swab and/or an oropharyngeal swab). The clearance and persistence of viral RNA was evaluated in two groups of positive patients: those who achieved two negative reverse transcription-polymerase chain reaction (RT-PCR) tests and those who kept testing positive. Patients were organized thereafter in two subgroups, mild illness patients discharged home and inpatients who had moderate to severe illness. Results from RT-PCR tests were then correlated with results from the evaluation of the immune response. The study evidenced that most patients tested positive for more than 2 weeks and that persistence of viral RNA is not necessarily associated with severe disease but may result from a weaker immune response instead.
新型冠状病毒病患者可根据临床症状缓解和上呼吸道病毒 RNA 清除的证据出院。了解严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）的病毒清除特征对于制定出院后再次检测计划和结束患者隔离至关重要。我们旨在评估患者需要多长时间才能使上呼吸道标本（鼻咽拭子和/或咽拭子）中 SARS-CoV-2 达到无法检测的水平。我们评估了两组阳性患者的病毒 RNA 清除和持续情况：那些达到两次阴性逆转录-聚合酶链反应（RT-PCR）检测的患者和那些持续检测呈阳性的患者。此后，患者分为两组亚组，轻症患者出院回家和中重度患者住院。然后将 RT-PCR 检测结果与免疫反应评估结果进行相关性分析。研究表明，大多数患者检测呈阳性超过 2 周，病毒 RNA 的持续存在不一定与严重疾病相关，但可能是由于免疫反应较弱所致。
