Today is Global Handwashing Day. And even in America, with soap and safe water easily accessible, it never hurts to remind everyone to do what mom used to say: wash your hands with soap. Even Elmo is on board, teaching kids to wash their hands often, for 20 seconds, with soap, while singing a song like Happy Birthday.

And for good reason. The truth of the matter is that handwashing with soap protects from several common diseases, including pneumonia and diarrhea. While these diseases aren’t fatal for most of us, for people in developing countries, especially children under the age of five, they can be.

Twenty-four thousand children under the age of five die every day from causes that we know how to prevent—causes such as diarrhea. In fact, diarrheal disease is second only to pneumonia as the leading killer of children worldwide and dirty hands make it easy for diarrheal disease to spread. Poor hygiene, lack of access to sanitation and unsafe drinking water together are responsible for 88 percent of diarrheal disease worldwide. Handwashing with soap, when done before eating and after using the toilet or changing a diaper, can cut that by nearly half. It’s a simple act that can save lives. We envision a day when that 24,000 unnecessary, daily deaths will be reduced to zero. We believe in zero.

A report released by UNICEF and the World Health Organization yesterday highlights the important reality that only by focusing on the preventable and treatable diseases that plague children of the developing world—like diarrhea—can we reduce global child mortality. The good news is that we know what works, and the measures to prevent and treat diarrheal disease are simple, effective, and cost-efficient.

Worldwide 1 billion people do not have access to safe water for drinking, let alone for handwashing. Child health advocates like me have long cried out for investments to assure children’s human right to be healthy and to have clean water. They also need investments that help them apply these interventions to their advantage, and yes, teaching children how to wash their hands is part of that.

In 2000, the United Nations set a challenge to all nations to commit to reducing global poverty and improving the health and welfare of people everywhere by 2015. This included a promise to stem child deaths by two-thirds.

We are well past the halfway point to 2015. Investments in health and development have made some progress toward reducing the number of child deaths, but now is the time to ensure that all of the tools we know to be effective in controlling disease throughout the western world are also used in a global effort to fight diarrheal disease. Prioritizing an integrated approach that includes handwashing with soap to control the spread of diarrheal disease is key in achieving Millennium Development Goal 4, reducing the under-5 mortality rate by two-thirds by 2015. The MDGs should be our guide, because children are at their heart.

Today is Global Handwashing Day. So, when you put down this paper, don’t forget to wash your hands. Oh sure, if you forget, you’ll survive. But remember others – especially children – around the world aren’t so lucky. Their well-being deserves our continued attention because all children deserve to celebrate their next birthday.

-Caryl M. Stern, President and CEO of The U.S. Fund for UNICEF