Soap vs. Sanitizer? Which Is Better?
Hand sanitizer is selling out, but soap is a much better defense against the coronavirus. All the experts agree that a thorough hand wash could prevent disease.
Amid the panic over the coronavirus outbreak, it seems, people have forgotten that soap and water are our best defense against disease.
"The humble act of washing with soap and water, followed by drying with a clean towel is the gold standard," Elizabeth Scott, an expert in home and community hygiene and professor at Simmons University, told Insider. "Hand washing with soap employs mechanical action that loosens bacteria and viruses from the skin, rinsing them into the drain."
The drying that follows makes the skin less hospitable to the bacteria and viruses that can make us sick.
Soap breaks down pathogens, and you're better off using liquid soap over barsoap in public
Evidence suggests the novel coronavirus is transmitted via droplets from sneezing or coughing that can land on anything, from tables to laptops to credit cards. It can live on surfaces for hours a day. If people touch something a droplet has landed on and then touch their faces, they can get infected.
The pathogen itself is encased in a lipid envelope, or layer of fat. Soap helps destroy that layer of fat, making the virus less capable of infecting you. Hand-washing can also remove pathogens from dirty hands.
Soap contains fat-like substances known as amphiphiles, which are similar to the lipids in the virus' envelope, Scott told Insider. These amphiphiles compete with the lipids in the virus envelope and deactivate the virus.
While bar and liquid soap are both equally effective, bar soap should not be used in public places, says Scott. Bar soaps are for home only, and shouldn't be used by people with skin infections.
Hand sanitizer should only be an option when you don't have access to a sink
Hand sanitizers with an alcohol content that is greater than 62% can also destroy these lipid membranes, according to Scott. But they are ineffective against non-enveloped viruses, like norovirus and rhinovirus, which are variations of the common cold. Plus they provide none of the virus-destroying friction that rubbing your hands together and rinsing provides.
According to Christopher Friese, a professor of nursing, health management and policy at the University of Michigan, hand sanitizer poses three challenges. There must be a high enough alcohol concentration to be effective, the entire surface of the hands and fingers must be covered, and skin irritation may occur. That's natural when rubbing something that is over 60% alcohol into your skin.
Here's how to wash your hands
According to the CDC, it doesn't matter whether you use hot or cold water, and there is no added benefit to using antibacterial soap. In fact, there is so little benefit that in September 2016, the FDA had to issue a ruling stating that 19 ingredients commonly marketed in anti-bacterial soaps had zero added benefit and were no longer going to be marketed to people.
"Using soap to wash hands is more effective than using water alone because the surfactants in soap lift soil and microbes from skin, and people tend to scrub hands more thoroughly when using soap, which further removes germs," says the CDC.
To wash your hands, lather them with soap and scrub for at least 20 seconds. Make sure to focus on places people tend to forget; the back of your hands, between your fingers, and under your nails, where microbes tend to build up. Rinse under clean running water and dry with a clean towel, as germs can easily be transferred to and from wet hands.
The CDC recommends a sanitizer that’s 60 percent alcohol, so beware of sanitizers or wipes on the market that don’t meet this standard (or contain alcohol at all). Hand sanitizer is useful, but it can fail in un-ideal situations. If your hands are wet or sweaty when you use the sanitizer, that can dilute it and diminish its effectiveness. Also, sanitizer doesn’t clean your hands of sticky grease to which viruses can also adhere. “Soap doesn’t really fail easily,” Thordarson says. It doesn’t really matter the formulation of soap, either. You don’t need “antibacterial soap” — which the Food and Drug Administration advises to skip altogether due to a lack of evidence of its usefulness. And you don’t need a super-harsh detergent like you’d put in your dishwasher or laundry machine. Simple soap works fine. “As long as you give it a little bit of time, it will do its job.”
