Westchester County, New York has one of the highest concentrations of coronavirus infections in the nation.

That has left teams of courageous nurses visiting more than a thousand homes to track the virus and quarantine its victims.

We're asking you not to go to work, not to go to school,

not to go food shopping, really just to stay home.

We have been following public health nurses in Westchester County.

I wonder what you think of their effort. God bless them. God bless them.

God bless them. Oh, see how strong. Dr. Mona is a bit of a superhero herself here because she was the

first to link the water to high levels of lead

in the children of Flint.

The word lead when you're a physician or a pediatrician signals what in your brain?

There is no safe level of lead.

It impacts cognition, how children think, actually drops IQ levels.

It impacts behavior leading to things like developmental delays and it has these life-altering

consequences.

You've heard a lot about the future of driverless cars.

But what about this?

That's right, 18 wheels on the road and nobody in the driver's seat.

Don't be surprised to see this on American Highway soon.

How close are we to the day when these trucks have no driver?

We'll be operating on the public highways with real cargo, with a real fleet in 2021.

I'm Leslie Stahl.

I'm Bill Whitaker.

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