Quantifying SARS-CoV-2 viral load: current status and future prospects
Mark J. Lee
Abstract
Viral load quantification is a critical measure that informs clinicians of treatment response, actionable viral load levels, and guidance on patient management. Additionally, for pathogens with epidemiological consequences, viral load can provide information to guide infection control measures and policies. While qualitative detection is sufficient to identify cases and initiate containment and mitigation measures in the vast majority of COVID-19 cases, in certain situations, SARS-CoV-2 quantification is needed to assess viral load trending. However, there are obstacles to quantification, including variability in respiratory specimen collection and the lack of commutable reference material. At the same time, the need for quantification for clinical and epidemiological management is growing, especially concerning individuals with prolonged RNA shedding.