Comparative RT-PCR Cycle Threshold Value Dynamics Among Asymptomatic to Symptomatic Patients of SARS-CoV-2: A Retrospective Analysis

Introduction: The standard molecular method for coronavirus disease 2019 (COVID-19) diagnosis is via real-time reverse transcription-polymerase chain reaction (RT-PCR). Real-time RT-PCR cycle threshold (Ct) values represent the number of amplification cycles required for the target gene to exceed a threshold level. This study asses RT-PCR Ct Value in asymptomatic individuals with SARS-CoV- 2 infection in compared to those in symptomatic patients. So, our study will be helpful for studying the dynamics of viral loads in the form of Ct Values in asymptomatic patients compared to symptomatic patients.Methodology: It is a retrospective cross-sectional study that includes two groups: asymptomatic and symptomatic patients. Data collected include patient details like age, gender, symptomatic status, RT-PCR test results, as well as Ct values in case of positive results. The data was extracted in MS Excel and analyzed using Stata v16.0. Quantitative variables like Ct value were summarized as Mean.Results: From April 2020 to May 2021, 46,219 cases were detected by RTPCR. The majority (88.6%) of the cases were asymptomatic, with only 11.4% symptomatic. The Ct value showed a slight but statistically significant decline across age groups from a Mean (± SD). The difference was more pronounced between extremes of age groups. (0 to 19 vs. 60 and above) The Ct value was significantly different between symptomatic 23.4 (± 5.4) and asymptomatic groups 25.4 (± 5.2).Conclusion: We report the importance of CT value, an indirect indicator of viral load. CT value is significantly high in asymptomatic patients as compared to symptomatic patients.