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Updated: Nov 24, 2025

Infection of Primary Nasal Epithelial Cells Grown at an Air-Liquid Interface to Characterize Human Coronavirus-Host Interactions
Published on: September 22, 2023
Chronic rhinosinusitis is associated with prolonged SARS-CoV-2 RNA shedding in upper respiratory tract samples: A
B Recalde-Zamacona1,2, A Tomás-Velázquez1,3, A Campo1,2
1From the, Covid19 Department, Clinica, Pamplona, Spain.
Background:
SARS-CoV-2, the COVID-19 causative agent, has infected millions of people and killed over 1.6 million worldwide. A small percentage of cases persist with prolonged positive RT-PCR on nasopharyngeal swabs. The aim of this study was to determine risk factors for prolonged viral shedding amongst patient's basal clinical conditions.
Methods:
We have evaluated all 513 patients attended in our hospital between 1 March and 1 July. We have selected all 18 patients with prolonged viral shedding and compared them with 36 sex-matched randomly selected controls. Demographic, treatment and clinical data were systematically collected.
Results:
Global median duration of viral clearance was 25.5 days (n = 54; IQR, 22-39.3 days), 48.5 days in cases (IQR 38.7-54.9 days) and 23 days in controls (IQR 20.2-25.7), respectively. There were not observed differences in demographic, symptoms or treatment data between groups. Chronic rhinosinusitis and atopy were more common in patients with prolonged viral shedding (67%) compared with controls (11% and 25% respectively) (P < 0.001 and P = 0.003). The use of inhaled corticosteroids was also more frequent in case group (P = 0.007). Multivariate analysis indicated that CRS (odds ratio [OR], 18.78; 95% confidence interval [95%CI], 3.89-90.59; P < 0.001) was independently associated with prolonged SARS-CoV-2 RNA shedding in URT samples, after adjusting for initial PCR Ct values.
Conclusion:
We found that chronic rhinosinusitis and atopy might be associated with increased risk of prolonged viral shedding. If confirmed in prospective trials, this finding might have clinical implications for quarantine duration due to increased risk of pandemic spread.
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