Should people be concerned about catching COVID-19 while using the bathroom? The virus can be found in the digestive tract. Consequently, if an infected person were to flush the toilet, particles might be launched into the air, where someone else might inhale them. We hesitate to add to people’s worry about toilets, but a new study suggests all toilets should have lids.
The Physics of Flushing:
Flushing the toilet create a toilet plume of fine mist. Physicists who study fluid behavior created computer models to simulate that action (Physics of Fluids, June 16, 2020). These indicated that tiny droplets can rise into the air about a yard above the toilet. If there were virus particles in the toilet, they too could become airborne.
To minimize the chance of spreading viral particles into the air, the authors recommend closing the lid before you flush the toilet and then washing your hands carefully. Public restroom without toilet lids theoretically pose more of a risk on two counts. First, the lack of lids means it is not possible to contain the toilet plume. Second, the public nature means that infected and uninfected individuals may both be using the facilities.
Do You Need to Close the Lid After You Flush the Toilet?
The CDC suggests that closing the toilet lid may be unnecessary in any event. This public health organization says that there are no confirmed reports of toilet flushing leading to COVID-19 transmission. On the other hand, determining how any given individual catches the disease is an enormous challenge.
One note: The authors of this paper on the physics of fluids write very clearly. We recommend it.