Clinical Characteristics and Factors Associated With Long-Term Viral Excretion in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection: a Single-Center 28-Day Study

Abstract

Background: Despite the ongoing spread of coronavirus disease 2019 (COVID-19), knowledge about factors affecting prolonged viral excretion is limited.

Methods: In this study, we retrospectively collected data from 99 hospitalized patients with coronavirus disease 2019 (COVID-19) between 19 January and 17 February 2020 in Zhejiang Province, China. We classified them into 2 groups based on whether the virus test results eventually became negative. Cox proportional hazards regression was used to evaluate factors associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding.

Results: Among 99 patients, 61 patients had SARS-CoV-2 clearance (virus-negative group), but 38 patients had sustained positive results (virus-positive group). The median duration of SARS-CoV-2 excretion was 15 (interquartile range, 12-19) days among the virus-negative patients. The shedding time was significantly increased if the fecal SARS-CoV-2 RNA test result was positive. Male sex (hazard ratio [HR], 0.58 [95% confidence interval {CI}, .35-.98]), immunoglobulin use (HR, 0.42 [95% CI, .24-.76]), APACHE II score (HR, 0.89 [95% CI, .84-.96]), and lymphocyte count (HR, 1.81 [95% CI, 1.05-3.1]) were independent factors associated with a prolonged duration of SARS-CoV-2 shedding. Antiviral therapy and corticosteroid treatment were not independent factors.

Conclusions: SARS-CoV-2 RNA clearance time was associated with sex, disease severity, and lymphocyte function. The current antiviral protocol and low-to-moderate dosage of corticosteroid had little effect on the duration of viral excretion.

Keywords: SARS-CoV-2; disease severity; lymphocyte function; risk factors; viral excretion.

Figure 1.

A, Cumulative proportion of patients with detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA among patients who were transferred to intensive care and those who were in the general ward, by day after illness onset. B, Cumulative proportion of patients with detectable SARS-CoV-2 RNA among those with Acute Physiology and Chronic Health Evaluation II score >10 and or ≤10, by day after illness onset. C, Cumulative proportion of patients with detectable SARS-CoV-2 RNA among those whose lymphocyte count was ≤0.5×10⁹/L and those whose lymphocyte count was >0.5 ×10⁹/L, by day after illness onset. D, Cumulative proportion of patients with detectable SARS-CoV-2 RNA among those with positive fecal viral RNA and those with negative fecal viral RNA, by day after illness onset. Abbreviations: APACHE II, Acute Physiology and Chronic Health Evaluation II; CI, confidence interval; HR, hazard ratio; ICU, intensive care unit; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.