My takaway is to avoid breathing the air in public restrooms, and maybe narrow hallways adjacent.
https://www.medscape.com/viewarticle/926856#vp_2
COMMENTARY
Fecal Evidence of COVID-19 Raises Transmission Concerns
David A. Johnson, MD
March 18, 2020
New studies are expanding our understanding of the possible fecal transmission of COVID-19. Assessment by polymerase chain reaction (PCR) has provided evidence of virus in the stool and the oropharynx outside the nasopharynx and respiratory tract.
Virus in the stool may be evident on presentation and last throughout the course of illness resolution for up to 12 days after the respiratory virus evidence is gone.
When I say "virus evidence," it's because it does not necessarily correspond to infectivity. Studies from fecal transmission to infectivity have yet to be done. However, it's certainly suggestive that the virus is intact, at least as far as how the PCR assay for the respiratory definition is now being applied the same way for stool.
Why Possible Fecal Transmission Is Important
The Centers for Disease Control and Prevention recommends that after two negative respiratory tests separated by ≥ 24 hours, patients can be dismissed from having transmissibility infection risk for COVID-19.
But we now know that these stools may lag up to 12 days after. In fact, in one of the most recent studies looking at 73 patients, approximately 24% remained positive in their stool for evidence of virus, though not necessarily infection, after showing negative in respiratory samples.
When we consider other disease states with fecal-oral transmission, the classic example that comes to mind is Clostridium difficile. We tell patients with C difficile–positive stool that when they use and flush the toilet, they can aerosolize these spores, which may then deposit on the surface areas in their bathroom.
...
The potential for fecal transmissibility has yet to be defined, but we know from a recent study that the virus has been evident in the stool of just over 50% of patients and remains in nearly 25% otherwise clear of respiratory evidence of virus.