Why is soap our biggest defense for Coronavirus?
First let’s start by thinking about a time when you had butter or oil on your hands after cooking a meal and you first tried to wash it off with water. It didn’t work, right? Even warm water wasn’t effective. That’s because water alone can’t break down fatty molecules. Now when you added and scrubbed with soap, it washed right off. Thanks to its hydrophobic (water-averse) and hydrophilic (water-attracting) properties, soap dissolves fatty substances quickly.
So what does this have to do with coronavirus? Coronavirus, like other viruses, is encased inside a lipid, which is a waxy coating that protects it and allows it to transfer from person to person. This lipid, just like oil and butter, is insoluble in water, but soluble in organic solvents. When washing with soap, you’re able to dissolve the lipid around the virus, which leaves the virus exposed and not able to survive. Rinsing literally washes it all away and down the drain.
Does it matter what kind of soap you use?
Not really. While natural soap is better for your skin because it doesn’t strip away all of your skin’s natural oils, any kind of soap will work. All soap is made up of hydrophobic and hydrophilic properties, which dissolve fatty substances, and that’s what you need to dissolve the lipid casing of the virus.
Web MD advises to use liquid, gel or bar soap over foam soap simply because people tend to “splash and dash” when using foam soap, which isn’t as effective in washing away the virus.
Is antibacterial soap better?
Not for viruses. Active bacterial-killing agents, such as triclosan do basically nothing to coronavirus; although, most products with antibacterial agents also contain alcohol and soap, which do help kill the virus.
Is hand sanitizer just as effective?
According to the CDC, soap is most effective, but hand sanitizer can be used as an alternative if soap is not available. Alcohol-based hand sanitizers can quickly reduce the number of microbes but they won’t kill all types of germs. The CDC recommends only using hand sanitizers that are 60 to 95 percent alcohol. Anything less than 60 percent may not work as well at killing germs and may just reduce their growth.
If you have to use hand sanitizer, it’s very important to rub it all over your hands and let it dry completely without wiping your hands off with a paper towel or using a dryer – which could take longer than washing with soap for 20 seconds.
The skin is rough and wrinkly, so the virus can hide in nooks and crannies. Washing, rubbing and rinsing for a longer period of time helps ensure you reach every part of the skin’s surface.
For more information and interesting findings about washing hands, check out this list of articles from the Centers for Disease Control and Prevention.