When the coronavirus pandemic was beginning, members of the public were urged to wash their hands more frequently and for longer periods of time (at least 20 seconds) in a move to get the spread of the virus under control.
While there are other measures in place to help control the spread, such as face masks, hand washing has remained extremely important in the fight against coronavirus.
But why exactly is handwashing so important? What makes it effective?
Here’s the science explained, step by step, by doctors.
Why is handwashing important?
A statement from Johns Hopkins Hospital explains why hand washing is so important.
It states that the virus is not a living organism - instead, the virus is a protein molecule which is covered by a protective layer of fat. When absorbed by the cells in our eyes, nose or mouth, the virus mutates their genetic code and converts them into aggressor and multiplier cells.
As a protein molecule and not a living organism, the virus itself cannot actually be killed - instead, it has to decay on its own. The rate of decay depends on the temperature, humidity and type of material where it lies.
“The virus is very fragile; the only thing that protects it is a thin outer layer of fat and that is the reason why soap or detergent is the best weapon,” the hospital statement explains.
The foam from the soap cuts through the fat, which is why washing your hands for at least 20 seconds is so important - it’s to create a lot of foam. By dissolving the fat layer, the protein molecule disperses and breaks down.
Heat also melts the protective fat layer as well, which is why it's important to use hot water for washing your hands, laundry and cleaning surfaces. Hot water also makes more foam, so making soap more effective.
What else breaks down the virus?
The Johns Hopkins advice says, “Alcohol or any mixture with alcohol over 65 per cent dissolves all fat, especially the external lipid layer of the virus.”
Any solution with one part bleach and five parts water also directly dissolves the protein, breaking it down from the outside.
Dehumidified, dry, warm and bright environments will degrade the virus faster. The virus molecules remain stable in colder temperatures, including air conditioning in houses and cars. It also needs moisture and darkness to stay stable.
UV light on any object that may contain the virus will break down the protein - but be careful, as UV light also breaks down collagen, another protein, which is found in our skin.
Is there anything I should avoid?
If you’re looking to use alcohol to target the virus, be aware that spirits like vodka are not strong enough. The strongest vodka is only 40 per cent alcohol, and you need a minimum of 65.
Vinegar is also not useful, as it cannot penetrate the outside protective layer of fat on the virus.
Johns Hopkins recommends that you should keep your nails short so you don’t provide the virus with a place to hide.