Soap and hand sanitizer are the two most common weapons used in the fight against germs. This page will tell you why they work and the benefits of each.

Why soap works to combat germs

Soap is made out of a combination of fat and ash. Soap works against microbes for two reasons:

I. It traps and rinses
When you wash your hand or face with soap and water, it helps dislodge microbes, trapping them in the slippery lather. Germs are then washed away and sent down the drain.

2. Soap kills pathogens
Soap can actually destroy viruses and other micro-organisms, because it possesses a unique structure that can rupture cell membranes. Soap molecules have a head that bonds with water and a tail that avoids it, sort of like a tadpole or a sewing pin. The water-shunning tails of these molecules can wedge themselves into the membrane of a pathogen and pry it apart. “They act like crowbars and destabilize the whole system,” says professor Paul Thordarson, acting head of chemistry at the University of New South Wales. (Jabr, 2020) A single drop of ordinary soap diluted with water is capable of killing many types of bacteria and viruses, including he new coronavirus.

Certain types of bacteria and viruses are more resistant than others. Some viruses don’t depend on lipid membranes, and some bacteria protect theirs inside a sturdy shell of protein and sugar-the bacterial equivalent ofan armored tank. Some of the more resistant microorganisms include those that cause meningitis, pneumonia, diarrhea and skin infections. The hepatitis A virus, poliovirus, and some rhinoviruses and adenoviruses are also more resistant.

Hand sanitizer and how it works

Hand sanitizers are made synthetically out of a variety of different chemicals, with some form of ethyl alcohol added to kill the germs. Liquid sanitizers are used primarily for their convenience, providing a way to cleanse one’s hands when there are no sinks readily available.

Which is better: Soap or hand sanitizer?

Hand sanitizers contain ethanol, which is similarly meant to kill viruses and pathogens. Sanitizers that contain at least 60% ethanol can work similarly to soap, destabilizing their lipid membranes. However, they don’t easily remove microorganisms from the skin. So soap is actually a better (and cheaper) way of fighting microbes, at least where you have access to a sink.

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