Why soap, sanitizer and warm water work against Covid-19 and other viruses
(CNN)Tired of washing your hands for 20 seconds each time? Fingers starting to prune or feel like sandpaper?
Please don't stop. ...
What soap and warm water do
Under the microscope, coronaviruses appear to be covered with pointy spires, giving them the appearance of having a crown or "corona" -- hence the name. Beneath the crown is the outer layer of the virus, which is made up of lipids, or what you and I would call fat.
Now imagine that coronavirus is your butter dish, covered with buttery fat.
"You try to wash your butter dish with water alone, but that butter is not coming off the dish," Williams explained. "You need some soap to dissolve grease. So soap or alcohol are very, very effective against dissolving that greasy liquid coating of the virus."
What does getting rid of that outer layer do to the germ?
"It physically inactivates the virus, so it can't bind to and enter human cells anymore," Wllliams said.
ust how soap accomplishes this feat is rather strange and fascinating science.
It's all about how soap molecules are formed -- each looks much like a tiny sperm, with a head and tail. The head bonds with water but the tail rejects it, preferring oil and fat.
Frantically trying to escape water, the tail of the soap is drawn to the fatty outer layer of the virus and begins to pry it open, much like we might use a crowbar to separate two pieces of wood.
Once the virus or bacteria splits open, it spills its guts into the soapy water and dies.
Water and scrubbing with your hands are important to this process because the combination creates more soap bubbles, which disrupt the chemical bonds that allow bacteria, viruses and other germs to stick to surfaces.
You want to scrub, build up bubbles and scrub some more, getting into every crack and crevice of your hands and fingers, including your fingernails, for 20 seconds, which is about as long as it takes to sing Happy Birthday twice. (But if you're tired of that ditty, there are songs from every decade you can sing instead.)
Now, when you rinse your hands, all the germs that have been hurt, trapped or killed by soap molecules are washed away.
"All those bubbles and foam ... literally pick germs up and wash them down the drain," said Dr. William Schaffner, a professor of preventative medicine and infectious disease at Vanderbilt University School of Medicine in Nashville.
Read the entire article on CNN.