A smile is infectious,

you catch it like the flu.

When someone smiled at me today,

I started smiling too.

I passed around the corner,

and someone saw my grin;

And when he smiled I realized,

I'd passed it on to him.

I thought about that smile,

then realized it's worth;

A single smile, just like mine,

could travel 'round the earth.

So, if you feel a smile begin,

don't leave it undetected.

Let's start an epidemic, quick,

and get the world infected.