Clinical Significance of Quantitative Viral Load in Patients Positive for SARS-CoV-2

Abstract

Cycle threshold (CT) refers to the number of cycles in a reverse transcriptase polymerase chain reaction (RT-PCR) assay needed to amplify viral RNA and can be used to indicate viral load. CT is inversely related to viral load, where lower CT values indicate higher viral levels. Data suggest lower CT scores are associated with worse outcomes in COVID; however, quantitative CT scores are not typically reported to patients. This retrospective analysis examined the use of CT scores in patient counseling for positive COVID results and suggests that higher viral loads were associated with greater need for prescription drug therapy in the outpatient setting. Patient perception of CT score was found to influence masking and quarantine behavior. We hypothesize that a quantitative threshold for viral load such as CT can be useful in patient counseling, estimating need for drug therapy, and influencing behavior toward public health concerns.