COVID-19: Is SARS-CoV-2 Also an enteric pathogen with potential fecal-oral transmission?

COVID-19: Is SARS-CoV-2 also an enteric pathogen with potential fecal-oral transmission? Spencer EA, Heneghan C.

https://www.cebm.net/study/covid-19-is-sars-cov-2-also-an-enteric-pathogen-with-potential-fecal-oral-transmission/

Published on July 9, 2020

Reference Ding S, Liang TJ. Is SARS-CoV-2 Also an enteric pathogen with potential fecal-oral transmission? A COVID-19 virological and clinical Review [published online ahead of print, 2020 Apr 27]. Gastroenterology. 2020;S0016-5085(20)30571-0. 2020
Study type
Country N/A
Setting N/A
Funding Details Non reported
Transmission mode Orofecal
Exposures

Bottom Line

Various observational and mechanistic evidence supports that SARS-CoV-2 can infect and be shed from the human gastrointestinal tract.

Evidence Summary

For SARS-CoV-2, angiotensin I converting enzyme 2 (ACE2) mediates entry into host cells

ACE2 is an X-linked gene and has sex-specific expression profiles, helping explain sex differences in COVID-19 severity. Smokers and individuals with chronic obstructive pulmonary disease have higher ACE2 expression levels.

There is evidence that SARS-CoV-2 can survive adverse conditions in the Gastrointestinal system

SARS-CoV-2 RNA has been identified in endoscopic specimens of the esophagus, stomach, duodenum, and rectum of COVID-19 patients; substantial amounts of SARS-CoV-2 RNA have been consistently detected in stool specimens.

What did they do?

This review aimed to summarize the literature on the potential of SARS-CoV-2 to infect the human gastrointestinal tract, and shed via the fecal route to generate orofecal transmission.

Study reliability

No search methods are reported and included studies were not assessed for quality.

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

What else should I consider?

CoVs belong to the Coronaviridae family within the Nidovirales order. They are enveloped, nonsegmented, positive-sense RNA viruses with a large genome of approximately 30 kb.

References 

  1. Landscape of X chromosome inactivation across human tissues. Nature. 2017;550:244–248. 
  2. Sex difference and smoking predisposition in patients with COVID-19. Lancet Respir Med. 2020;8 
  3. ACE-2 expression in the small airway epithelia of smokers and COPD patients: implications for COVID-19. Eur Respir J. 2020;55(5) 
  4. SARS-CoV-2 receptor ACE2 is an interferon-stimulated gene in human airway epithelial cells and is detected in specific cell subsets across tissues. Cell 10.1016/j.cell.2020.04.035. 
  5. ACE2 gene polymorphism and essential hypertension: an updated meta-analysis involving 11,051 subjects. Mol Biol Rep. 2012;39:6581–6589.

Figure 1. A simplified image of the SARS-CoV-2 replication cycle. 

https://pubmed.ncbi.nlm.nih.gov/32353371/#&gid=article-figures&pid=figure-1-uid-0

Figure 3. Modes of transmission of SARS-CoV-2 in humans. 

https://pubmed.ncbi.nlm.nih.gov/32353371/#&gid=article-figures&pid=figure-3-uid-2

About the authors

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

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