We cannot let our guard down, because a series of genetic changes could happen at any time that could allow this virus to pick up the capacity to move from person to person.

We will be staying home, concerts won't be going on. We might close schools in some communities.

The kids were giving the hepatitis A virus to mom, dad and Uncle Tom. And so if they didn't get the disease, the parents were protected.

People are trying to work out contingency plans to make sure there's a more equitable distribution. I'm sure it will never be perfect, but without work now, it'll certainly be chaotic later.

This is a hugely important first step.

It's become one of the dominant infections of childhood.