Overview of SARS-CoV-2 viral load and its clinical value
CHEN Ai-ping1,4, LI Tian-ping2, LING Hua3,4, ZHANG Yong-jun1,4
1. Chongqing Medical and Pharmaceutical College, Chongqing 401331,China; 2. Chongqing Municipal Key Laboratory for High Pathogemic Microbes, Chongqing 400042,China; 3. Chongqing Health Center for Women and Children, Chongqing 400013,China; 4. Chongqing Center for Disease Control and Prevention, Chongqing 400042,China
Abstract：During the unprecedented COVID-19 pandemic, detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral nucleic acids in diverse specimens from patients, people with suspected infection and their close contacts has been widely implemented in infection confirmation, patient management and transmission prevention. Viral nucleic acid detection results not only reflect the infection status in suspected cases, but also are used to quantify positive specimens in most assays. For most viral diseases, viral loads are theoretically associated with potent infectivity and prognostic outcomes in patients. In this review, the principles and characteristics of SARS-CoV-2 viral load detected by real time reverse transcription PCR (RT-PCR) and digital PCR are summarized. The distribution and dynamic changes in viral load in humans are discussed, and the correlations of viral load with disease severity, infectivity and prognostic indicators are analyzed. The comprehensive descriptions of COVID-19 characterization will help guide current practices in infection control, patient treatment and management, and combating the ongoing COVID-19 pandemic.
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2021, Vol. 37 
