The Source of Infection

The fly is the source of infection
Some wild guy told me
The fly is the source of infection
Believe me it's not so
The source of infection is you
My fly is like glazed bread
Fat and glistening
My fly is like glazed bread
Has a tidy appearance
Not like you
The source of infection
Don't kill flies
Don't kill flies
Don't kill flies
For how long I've fed you
With only swearing in response
How many flies I've killed
How many poor ones have gone
But you're still alive the source of infection
What if, instead of a fly,
I slammed you down
Slammed down and flicked you with my nail?
But I let you live
You, the source of infection