This question is causing enormous concern during the current Coronavirus outbreak, fuelled by panic and hysteria. When cleaning our hands broadly speaking we have 2 options:
Traditional bars of soap & liquid soaps
Soap is an amazing product, the soap molecule has two different ends, one that is hydrophilic that binds with water and the other that is hydrophobic that binds with grease, oil, bacteria or germs.
When we wash our hands and create a good lather bacteria, germs, dirt & oil mix with the soapy water, the soap molecules then arrange themselves into tiny clusters called micelles.
The hydrophobic parts then stick to the germs or oils and trap them in the centre preventing them from coming into contact with the water. With the germs and oils safely tucked away in the centre, the micelle is soluble in water. As the soapy water is rinsed away the germs and oils go along with it.
Always use plenty of soap and create a rich lather covering all surfaces of your hands. The recommendation of 20 seconds is to ensure that this lather reaches the entire surface and gets an opportunity to literally suck away the pathogens from your skin.
Of equal importance is rinsing your hands all over to allow these pathogens to be freely flushed down the plug hole.
Help the Scientist's fight
Help scientists by airing your opinion on COVID-19; download the App - your poll votes will help in efforts to understand, model, and improve future responses to pandemics.
AMO sends your votes securely via standard SMS, these are usually included free in UK airtime bundles. Ask your mobile supplier if you get inclusive SMS to standard UK mobiles.