A paper in press in Gastroenterology (preprint) reports on examination of fecal samples from 71 patients in China who were symptomatic for COVID19. 53% of the patients were positive for SARS-COV-2 RNA in their feces, and of these 17 had negative respiratory tests for SARS-CoV-2.
The authors did a detailed workup of gastrointestinal cells harvested from one patient by endoscopy. Microscopic examination using fluorescent stains showed evidence of viral capsids within these cells, suggesting active infection of these tissues.
No samples were taken for detection of virus by tissue culture, which would be needed to demonstrate viable virions.
The authors suggested:
“Therefore, fecal-oral transmission could be an additional route for viral spread. Prevention of fecal-oral transmission should be taken into consideration to control the spread of the virus. …
Therefore, we strongly recommend that rRT-PCR testing for SARS-CoV- 2 from feces should be performed routinely in patients with SARS-CoV-2 and that transmission-based precautions for hospitalized patients with SARS-CoV-2 should continue if feces test results are positive by rRT-PCR testing.”