On the occasion of the fifth annual Global Handwashing Day, Unicef emphasized that the very simple act of washing hands with soap can save thousands of children who die every year.
Child mortality figures released by the UN agency last month showed that around 2,000 children under five die each day from diarrhoeal diseases, Xinhua reported.
Of these, the vast majority - about 1,800 children per day - die due to lack of safe water, sanitation and basic hygiene.
Though the number has significantly declined in the five years since Global Handwashing Day was established, the Unicef said it was still too high.
"Global Handwashing Day is more than just a day," said Therese Dooley, the Unicef's senior advisor on sanitation and hygiene.
"We want the message to spread from children to families, communities and nations. Halting the spread of diarrhoeal disease is not complicated, or costly, but it is critically important that handwashing with soap becomes routine for everyone."
Global Handwashing Day is celebrated annually Oct 15.
The Global Public-Private Partnership for Handwashing with Soap initiated the day in 2008.
In Ethiopia, five million people took part in public handwashing events, while in India, children in 1.3 million primary and upper primary schools celebrated the day, the report said.
In Yemen, Unicef and its partners sent SMS texts to 2.5 million mobile phone users about the importance of handwashing, while almost one million school children took part in related activities.
In Vietnam, the campaign started with a TV spot featuring comedian Xuan Bac, who sings a handwashing song with children.
"We are pulling out all the stops to ensure that everyone gets the message. You don't need to invent some Nobel Prize winning formula to save millions of children. The solution already exists -- soap and water," Dooley said.