You may be reluctant to go out to crowded areas now, especially since older adults are at increased risk of developing complications from COVID-19. But new research suggests there may be another reason to be worried: public bathrooms. A study published this past June in the journal Physics of Fluids found that the simple act of flushing can force as much as 60 percent of produced aerosols, which could be potentially infectious, high above the toilet seat (a phenomenon known as “toilet plume"). Another study published in the same journal in August found similar results with urinals —and, in fact, the tiny particles were able to rise even faster than when they were flushed from a toilet.
But whether or not these aerosols can actually infect you with COVID-19 is unknown. “The significance of the so-called ‘toilet plume’ is unclear,” says Albert C. Shaw, M.D., a Yale Medicine professor and infectious disease specialist. “Flushing the toilet does generate aerosolized particles that can contain viruses, and this raises the possibility of generating contaminated surfaces that could transmit COVID-19. But whether this is responsible for actual transmission of disease is not clear.” In addition, the novel coronavirus tends not to live that long in your intestines, adds Joshua Santarpia, an associate professor of pathology and microbiology at the University of Nebraska Medical Center. “It's difficult to extract the virus from both feces and urine,” he says.