Fecal viral shedding in COVID-19 patients: clinical significance, viral load dynamics and survival analysis

Highlights

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  Fecal SARS-CoV-2 was relevant to milder condition and better radiological recovery.

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  The first attempt of using a survival analysis for SARS-CoV-2 RNA duration.

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  SARS-CoV-2 RNA survival in feces was significantly longer than in oropharyngeal swabs.

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  In spite of the negative oropharyngeal swabs, Fecal viral load easily rebounded.

Abstract

Background

To investigate the clinical significance, viral shedding duration and viral load dynamics of positive fecal SARS-CoV-2 signals in COVID-19.

Methods

COVID-19 patients were included. SARS-CoV-2 RNA was tested in stool and respiratory specimens until two sequential negative results were obtained. Clinical, laboratory and imaging data were recorded.

Results

Of the 69 COVID-19 patients, 20 (28.99%) had positive fecal viral tests who were younger, had lower C-reactive protein (CRP) and fibrinogen (FIB) levels on admission (all P < 0.05), and showed more improvement and less progression on chest CT during recovery. The median duration of positive viral signals was significantly longer in stool samples than in respiratory samples ( P < 0.05). In spite of the negative oropharyngeal swabs, eleven patients were tested positive for viral RNA in stool specimens, with their fecal SARS-CoV-2 RNA Ct values reaching 25-27. 6 of these 11 patients' Ct (cycle threshold) values rebounded.

Conclusion

SARS-CoV-2 RNA in stool specimens was associated with a milder condition and better recovery of chest CT results while the median duration of SARS-CoV-2 RNA persistence was significantly longer in fecal samples than in oropharyngeal swabs. The fecal viral load easily reached a high level and rebounded even though respiratory signals became negative.