When you say that after World War I there was a pandemic that killed more people than the war itself, most will say: "Wait, are you kidding? I know World War I, but there was no World War 1.5, was there?" But people were traveling around after the war, and that meant the force of infection was much higher. And the problem is that the rate of travel back then was dramatically less than what we have nowadays.

The returns from investing in poor people are just as great as the returns from investing in the business world... and have even more meaning

Take agriculture, where we haven't done much, or sanitation; saying, "okay, we will be able to make a really huge effort there." It really energized the foundation and half of what we've gotten done in this last decade is because Warren [Buffett] trusted us.

Haiti should remind us all that there is an immediate need to invest in and promote long-term development projects that are sustainable, scalable, and proven to work.

The world today has 6.8 billion people...that's headed up to about 9 billion. If we do a really great job on vaccines, health care, reproductive health services, we could lower that by perhaps 10 to 15 percent.

The key thing you can do to reduce population growth is actually improve health.

Getting the word out that, yes vaccines are great, the safety data's very, very clear, including any of these specific concerns, that's very important to our foundation.