Smiling 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...
 When he smiled I realized,
I'd passed it on to him.
 I thought about that smile,
then I realized its 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!