Cycle threshold values in RT-PCR to determine dynamics of SARS-CoV-2 viral load: An approach to reduce the isolation period for COVID-19 patients
Cycle threshold values in RT-PCR to determine dynamics of SARS-CoV-2 viral load: An approach to reduce the isolation period for COVID-19 patients
复制标题
DOI：
10.1002/jmv.27206
复制
发表时间：
2021-07-23
影响因子：
12.7
通讯作者：
Gogoi, Dimpu
中科院分区：
文献类型：
--
作者：
Aranha, Clara;Patel, Vainav;Gogoi, Dimpu
严重急性呼吸综合征冠状病毒（SARS-CoV-2）已经影响了所有有人居住的大陆，印度目前正在经历毁灭性的第二波冠状病毒病-2019 （COVID-19）。本研究采用实时逆转录聚合酶链反应（RT-PCR）检测了207例感染病例呼吸道样本中SARS-CoV-2的清除时间。大量周期阈值（Ct）大于或等于31的COVID-19阳性病例（45.7%）随后在最初检测病毒载量的7天内检测出SARS-CoV-2 RNA呈阴性。在所有COVID-19患者中，无论其Ct值如何，总共有60%的患者在首次检测后14天内清除了SARS-CoV-2 RNA。对需要15-30天清除SARS-CoV-2 RNA的个体的RT-PCR检测结果的纵向评估显示，在病毒载量高或中等的样本（Ct值= 31）中，病毒载量显著降低，病毒载量稳定。总之，这些结果表明，Ct值大于或等于31的COVID-19阳性病例需要缩短清除SARS-CoV-2的时间，因此，可以考虑缩短这一群体的隔离时间，以便在COVID护理中心提供足够的空间，并减轻医疗基础设施的负担。
Severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected all inhabited continents, and India is currently experiencing a devastating second wave of coronavirus disease-2019 (COVID-19). Here, we examined the duration of clearance of SARS-CoV-2 in respiratory samples from 207 infected cases by real-time reverse-transcription polymerase chain reaction (RT-PCR). A substantial proportion of COVID-19 positive cases with cycle threshold (Ct) values more than or equal to 31 (45.7%) were subsequently tested negative for SARS-CoV-2 RNA within 7 days of initial detection of the viral load. A total of 60% of all the patients with COVID-19, irrespective of their Ct values, cleared SARS-CoV-2 RNA within 14 days of the initial detection. Longitudinal assessment of RT-PCR test results in individuals requiring 15-30 days to clear SARS-CoV-2 RNA showed a significant reduction of the viral load in samples with high or intermediate viral loads (Ct values = 31) exhibited a stable viral load. Together, these results suggest that COVID-19 positive cases with Ct values more than or equal to 31 require reduced duration to clear SARS-CoV-2, and thus, a shorter isolation period for this group might be considered to facilitate adequate space in the COVID Care Centres and reduce the burden on healthcare infrastructure.