It’s well-known, if not always well-observed, hygiene advice: close the lid of the toilet seat before flushing, or you risk potentially infectious particles of fecal matter spreading throughout the bathroom forming a thin, invisible film. fog.
A 2022 study by the University of Colorado in Boulder, US, seemed to confirm the received wisdom.
The researchers used lasers to illuminate the “plumes” of fog that rise from the container when the toilet is flushed and found that they can reach 1.5 meters high in eight seconds. Bath water in aerosol form also spreads horizontally.
The concern is that if the last person to use the bathroom had a highly infectious disease, such as norovirus or hand, foot and mouth, which is known to be transmitted through feces and through other forms of transmission, the next user could Unknowingly being exposed to bacteria or viruses in the air and other surfaces, especially in public bathrooms.
And at this time of year, when many diseases are rampant, caution is more important than ever.
Dr. Primrose Freestone, professor of clinical microbiology, says proper handwashing is key
“When you flush the toilet, there will be traces of whatever you put in the bucket in the mist that is created by the water,” says Dr Primrose Freestone, associate professor of clinical microbiology at the University of Leicester.
«Human feces can contain a number of potential transmissible pathogens: Campylobacter, candid, cryptosporidium, enterococcus, Escherichia coli, Salmonella, Shigella, Staphylococcus, Streptococcus and yersina bacteria, as well as viruses such as norovirus, rotavirus and hepatitis A and E, and Covid-19, to name just a few.’
The Colorado study, published in the journal Scientific Reports, did not test how much spray was reduced when the lid was closed before flushing.
But new research suggests that even closing it doesn’t solve all of these pathogenic problems.
In the study, published in the American Journal of Infection Control, researchers at the University of Arizona found that although lowering the lid reduced spray somewhat, it did not significantly prevent areas around the bathroom from becoming contaminated.
Not surprisingly, the lid and seat were the most contaminated areas in all cases, although some contamination was also observed on the walls and floor.
“The risk of infection would be reduced (by lowering the lid) as the spray path from the discharge is reduced, but now you have to clean a contaminated lid,” says Dr. Freestone.
‘So wipe the lid with a tissue and then spray with an anti-infective surface spray or bleach; let dry naturally.
‘While working on the lid, it would be a good idea to clean the seat and flush handle. And then wash your hands well.
But even if you don’t manage all of this, this last instruction (washing your hands) is the key.
After all, no study has yet shown that these plumes can definitively lead to infection, since it is the dose of fecal pathogens (the number of germ cells) that determines whether an infection sets in, says Dr. Freestone.
And while “contamination by fecal matter in the environment (called sewage) is considered a major source of human infection,” it is not known whether there is enough of any pathogen expelled from toilet flushes to cause illness.
Instead, infections “typically come from ingesting contaminated food or from the transfer of bacteria from hand to mouth as a result of fecal contamination of hands, food, and objects or surfaces,” explains Dr. Freestone. .
Clean all bathroom surfaces regularly with disinfectant to avoid getting infected.
It is dirty hands that spread contamination to surfaces and other hands that then pick up those bacteria or viruses and transfer them to our mouth or eyes (when we rub them).
“So handwashing is very important, but not everyone washes their hands properly after using the bathroom, so anything those dirty hands touch can become contaminated with feces,” warns Dr. Freestone.
“Hands that have just wiped their butts could press the lever of a soap dispenser, or turn on a faucet and turn off (with now clean hands) the same (now contaminated) faucet.”
Therefore, at home, regularly clean all bathroom surfaces with disinfectant and be religious about your hand hygiene at all times to avoid getting infected.
You can also alleviate any concerns about possible infection from toilet plumes by cleaning towels, bath mats, and washcloths frequently.
As Dr. Freestone explains: “In an open bathroom, the spray from the toilet could reach the towels; the distance that spray travels depends on the water pressure and how close the towels are to the toilet.”
Based on the fact that the Colorado study showed that spray from an open toilet could reach 1.5 meters high and that the sprayer moved with the breeze, most small and medium-sized bathrooms could have towels in potential proximity. of the column.
“To kill germs on bath or hand towels, the NHS recommends washing them with laundry detergent at 60°C after each day of use,” adds Dr Freestone.
“This prevents towels from smelling musty and ensures they are properly disinfected, which is important if towels are shared or if someone in the house has a communicable infection.”
And finally: one more reason to keep your things organized and stored in the bathroom cabinet instead of leaving toothbrushes, makeup and wipes on the counter.
“Keeping your toothbrush covered is a good idea as it prevents it from being potentially contaminated by flying insects crawling on it and depositing germs, dust settling on it, or contamination from random droplets from the toilet sprayer,” he adds. Dr. Freestone.
“The NHS recommends rinsing your toothbrush with hot water after each use and letting it air dry between uses.”
After all, mom was right to put things away neatly!
