Factors Associated with the Delayed Termination of Viral Shedding in COVID-19 Patients with Mild Severity in South Korea

Background and objectives: We aimed to analyze factors associated with the period of viral shedding in patients with confirmed COVID-19 who experienced only mild symptoms. Materials and methods: We conducted a multicenter retrospective study from three community treatment centers (CTCs) of South Korea. All patients included were admitted to the three centers before 31 March 2020. We collected data about clinical characteristics and the result of real-time reverse transcription polymerase chain reaction (RT-PCR). Results: Viral shedding was terminated within 32 days and 36 days in 75% and 90% of patients, respectively (range: 8-49 days). The mean period of viral shedding was 23.8 +/- 8.7 days. In the multivariate Cox proportional hazards regression analysis, the existence of underlying comorbidities lowered the probability of the termination of viral shedding (HR = 0.561, 95% CI 0.388-0.812). Female sex and presence of COVID-19-associated symptoms also lowered the probability, but the significance was marginal. Conclusions: The existence of underlying comorbidities was associated with delayed termination of viral shedding in COVID-19 patients with mild severity.