I think that people's resistance to vaccination isn't going to disappear until we address some of the nonmedical reasons for that resistance and people's discomfort and distrust of the government. That's bigger than what most medical professionals can handle.

On the pro-vaccine side - and not everyone does this, but I saw it enough for it to make me really uncomfortable - is a tendency to accuse people who are wary of vaccination of being stupid and not understanding science.

Herd immunity is, it turns out, not incredibly easy to understand. It took me quite a bit of reading before I fully grasped it. But understanding herd immunity is essential to understanding why we vaccinate the way we do.

Nigeria and Pakistan are two countries that have had a lot of trouble with polio. And part of the reason is that there's a lot of political unrest, and people really distrust what the government is doing. That has an effect on people's health, and it has an effect on the health of children.

When you experiment with new forms of exercise, you stay motivated on a daily basis.

Take Hispanic voters. They favor Democrats because they like the party's programs, from health care reform to government spending on education. It's not because the Republicans don't have a big enough Office of Hispanic Outreach.

I love to exercise outside in the fresh air and sun: hiking, swimming, stand-up paddleboarding, and jogging.

In choosing global corporate partners UNICEF emphasises compatibility with our core values and looks to build alliances that advance our mission of ensuring the health, education, equality and protection for all the world's children.