Tom Frieden

New, unfamiliar, and mysterious threats to our health are scary. At the Centers for Disease Control and Prevention - where we identify, on average, one new health threat each year - we work around the clock with an approach that prioritizes finding out what we need to know as fast as we can to protect Americans.

When people said Africa would change me, I didn't understand what they meant. To see the poverty in the townships, for instance, is overwhelming. I found it heart-wrenching to see young children walking barefoot and hungry in the dirt. I'm the kind of person who wants to change the world right here and now, so I got frustrated.