Does soap kill Covid 19?
As the coronavirus emerged as a worldwide health emergency in February, health agencies scrambled to advise people how to protect themselves from the new virus. One suggestion – repeated day after day, on news bulletins, adverts and expert interviews – was to wash hands with soap, in warm water, for at least 20 seconds.
Thomas Gilbert, an associate professor of chemistry and chemical biology at North Eastern University in Boston, Massachusetts, says coronavirus’s chemical makeup can be disrupted by nothing more specialised than soap and warm water.
“These viruses have membranes that surround the genetic particles that are called lipid membranes, because they have an oily, greasy structure,” he says. “It’s this kind of structure that can be neutralised by soap and water.” Dissolving this outer “envelope” breaks the virus cell up, and the genetic material – the RNA which hijacks human cells to make copies of the virus – is swept away and destroyed.
Why is 20 Seconds important?
“What you want to be doing is wetting your hands, getting the soap and working up a proper lather and then rubbing your hands for a good 20 seconds and get into all the nooks and crannies.” This gives enough time, Gilbert says, for the chemical reaction to take place between the lipid membrane and the soap. “There are other benefits – it also allows the soap to do a good job getting rid of the material.” And with warm water, Gilbert adds, all that virus fighting “happens a little quicker”.
Martin Michaelis, a professor of molecular science at the University of Kent in the UK, says water on its own is not enough to disable the virus. “When you have olive oil on your fingers when you’re cooking, it’ very hard to get rid of it with just water,” he says. “You need soap.” When it comes to the coronavirus, soap is needed in the same way “to remove that lipid envelope so that all the virus is deactivated”.
Hand washing’s effectiveness has been somewhat side lined due to the wide adoption of hand sanitisers, either the small bottles people take with them out of the house or the stations people are asked to use when they enter supermarkets and bars.
It’s not a bad idea to have something like that in your car, or inside the front door,” Gilbert says. “These things are good for when you don’t have access to a sink and soap and water. I would always prefer soap and water to hand sanitisers.”
Whilst handwashing has become a part of our daily routine, in many parts of the world, safe access to running water simply isn’t an option, which is why ChooseWell is proud to help fund water, sanitation and hygiene projects through our partner organisation, justadrop.org