SARS-CoV-2 (COVID-19) virus shedding period among Bhutanese population during pandemic: a retrospective cohort study from Bhutan

Abstract

Abstract Background: Bhutan detected its first COVID-19 case on 5th March 2020 and implemented stringent public health measures. This study aims to describe the molecular characterization of SARS-CoV-2 and the duration of viral shedding among Bhutanese population during the pandemic. Methods: This retrospective quantitative study included 500 COVID-19 laboratory confirmed positives from four PCR testing labs from March 2020 to August 2021. The data were extracted from COVID-19 Integrated Influenza Surveillance System. Descriptive statistics and student t-test were used to analyze the data in STATA version 13.1. Results: The median detection period from onset of symptoms to the first RT-PCR positive was 4 days (IQR, 2 – 12). The median period of virus shedding was 14 days (IQR, 8 – 27). The median period of virus shedding was longer in symptomatic cases (23 days) than the asymptomatic cases (11 days). The median Ct value of RT-PCR assay for 2020 was 31.95 (23.36 – 35.45), while for 2021 was 21.67 (16.17 – 29.15). Conclusion: The findings suggest that SARS-CoV-2 can be detected for a long duration but the sensitivity of RT-PCR test is high during the early stage of infection.