Vaccines are a miracle. With just a few doses, they protect children from deadly diseases for a lifetime. They are extremely cost-effective, and they save lives. Vaccines led to the eradication of smallpox, and they are responsible for the amazing fact that polio cases have gone down by 99 percent in just 20 years.

Over the next five years, as the world rallies to meet Millennium Development Goal 4 to reduce child mortality, we need to make sure that people understand the value of vaccines. (This video makes the case very clearly.) We often take them for granted in the developed world.

In fact, it was the realization that children in wealthy countries have access to vaccines while children in the developing world are dying from preventable diseases that motivated Bill and me to start our foundation. We simply could not accept that these types of inequities existed. We believe all children should have the same access to vaccines, no matter where they live.

That’s why Bill and I called for this year to initiate the Decade of Vaccines. We committed significant resources to this effort and asked the global community to work with us to save 8.7 million children’s lives during the next 10 years. I know that, together, we can reach this goal.

Currently, there are vaccines for pneumonia and diarrhea—the two leading causes of death in young children—and we have to focus on making sure that the children who need them can get them. Also, there are some promising vaccine candidates for other major diseases, including malaria.

As a result, vaccines play a critical role in progress toward the Millennium Development Goals (MDGs) 4, 5, and—over time—6. I will be discussing the MDGs at TEDxChange on September 20, and invite you to watch the live webcast.