The presence of SARS‐CoV‐2 RNA in the feces of COVID‐19 patients

The presence of SARS‐CoV‐2 RNA in the feces of COVID‐19 patients. Spencer EA, Heneghan C.

https://www.cebm.net/study/the-presence-of-sars%e2%80%90cov%e2%80%902-rna-in-the-feces-of-covid%e2%80%9019-patients/

Published on July 27, 2020

Reference Chen Y, Chen L, Deng Q, et al. The presence of SARS-CoV-2 RNA in the feces of COVID-19 patients.  J Med Virol. 2020;92(7):833-840. doi:10.1002/jmv.25825
Study type
Country China
Setting Hospital
Funding Details National Natural Science Foundation of China,
Transmission mode Orofecal
Exposures

Bottom Line

Sixty seven percent (28/42) laboratory-confirmed hospitalised COVID-19 patients tested positive for SARS-CoV-2 RNA in stool specimens; this was not associated with the presence of GI symptoms or severity of illness. Among them, 18 (64%) patients remained positive for viral RNA in the feces after the pharyngeal swabs turned negative, for a duration of 6 to 10 days.

Evidence Summary

A total of 42 laboratory-confirmed cases were enrolled, 8 of whom had gastrointestinal symptoms.  28 (67%) patients tested positive for SARS-CoV-2 RNA in stool specimens, and this was not associated with the presence of gastrointestinal symptoms and the severity of illness. 

Among them, 18 (64%) cases remained positive for viral RNA in the feces after the pharyngeal swabs turned negative.  The duration of viral shedding from the feces after negative conversion in pharyngeal swabs was 7 (6 to 10) days, regardless of COVID-19 severity. 

The demographics, clinical characteristics, laboratory and radiologic findings did not differ between patients who tested positive and negative for SARS-CoV-2 RNA in the feces.  Viral RNA was not detectable in urine specimens from 10 patients.

What did they do?

Retrospective single centre study including COVID-19 patients admitted to Zhongnan Hospital in Wuhan between 20th January to 9th February 2020.

The study investigated SARS-CoV-2 shedding in the excreta of COVID-19 patients up until 20th February 2020.   Electronic medical records, including demographics, clinical characteristics, laboratory and radiological findings of enrolled patients were extracted and analyzed. 

Pharyngeal swab, stool, and urine specimens were collected and tested for SARS-CoV-2 RNA by real-time reverse transcription-polymerase chain reaction.  Viral shedding at multiple time points in specimens was recorded, and its correlation analyzed with clinical manifestations and the severity of illness. 

Our results demonstrated the presence of SARS-CoV-2 RNA in the feces of COVID-19 patients and suggested the possibility of SARS-CoV-2 transmission via the fecal-oral route.

Study reliability

This is a relatively small study of 42 participants, and is retrospective and therefore open to recall bias.  The report does not specify how the 42 participants were selected/whether there were other eligible participants that did not give informed consent. 

The authors point out that clinically-diagnosed, PCR-negative cases were not included in this study. A longer follow-up is needed for 3 cases who still showed positive test results at the end of follow-up, 20th February 2020.

Clearly defined setting Demographic characteristics described Follow-up length was sufficient Transmission outcomes assessed Main biases are taken into consideration
Yes Yes No No No

What else should I consider?

It was not clear whether live viruses can be excreted.

About the authors

Carl Heneghan

Carl Heneghan

Carl is Professor of EBM & Director of CEBM at the University of Oxford. He is also a GP and tweets @carlheneghan. He has an active interest in discovering the truth behind health research findings

Elizabeth Spencer

Elizabeth Spencer

Dr Elizabeth Spencer; MMedSci, PhD. Epidemiologist, Nuffield Department for Primary Care Health Sciences, University of Oxford.