Handwashing with soap is one of the most effective and least expensive ways to prevent the spread of disease, but timing matters. Five moments are especially important: before preparing or eating food, after using the toilet, after cleaning a child who has used the toilet, after handling rubbish or raw food like meat, and after caring for someone who is sick.
Proper handwashing means wetting hands, applying soap, and rubbing all surfaces — including between fingers and under nails — for about twenty seconds, roughly the time it takes to say a short rhyme, before rinsing with clean water.
Where running water is limited, a simple tippy-tap (a hanging container with a small hole, tipped to pour water over the hands) can make handwashing with soap practical even without a tap.
Soap, not water alone, is what breaks down the germs on hands — plain water rinses away visible dirt but is much less effective against the bacteria and viruses that cause illness.