Twenty percent of all the babies born in the world each year—the equivalent of nearly five times the children born yearly in the United States—are not getting the basic vaccines they need to be protected from killer diseases, such as measles. And that’s why Venetia Dearden traveled to West African nation of Mali with Médecins Sans Frontières (MSF) to see firsthand the importance of vaccines to families and the lengths to which they must go to get them. When MSF teams stage vaccination campaigns in the West African nation of Mali, mothers will come from hours away, sometimes days away.