Body & HealthHow it works

Why soap doesn't kill viruses – it tears them apart.

Soap molecules have a water-loving and a fat-loving end. The fat-loving end burrows into the lipid envelope of viruses and bacterial membranes and breaks them open – the debris is rinsed away with water. That takes time: at least 20 seconds, including thumbs, fingertips and backs of hands.

Useful: Humming “Happy Birthday” twice is your 20-second timer.

Source: cdc.gov

HygieneMikroben

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