Leadership is about vision and responsibility, not power.

For just a few dollars a dose, vaccines save lives and help reduce poverty. Unlike medical treatment, they provide a lifetime of protection from deadly and debilitating disease. They are safe and effective. They cut healthcare and treatment costs, reduce the number of hospital visits and ensure healthier children, families and communities.

The best vaccine imaginable is only valuable to the extent we get it to everyone who needs it.

Leadership is about vision and responsibility, not power.

As many times as [HIV] changes its clothes, it's still wearing the same socks, and now our job is to make sure we get the body to really hate those socks.

When it comes to providing aid, developing innovations and making bold steps that change the course of history, the United States is usually on the front lines.

We've actually eliminated Type II polio in the world, at least as far as we can tell.