Who Busted Out A Time Machine When I Wasn't Looking?

A baby down in Oz has died because
Her neighborhood was seething with disease --
Not AIDS, Ebola, swine flu -- I must pause,
And scream before I go on; pardon, please.
'Twas whooping cough that killed this little girl:
Preventable since 1925!
She was too young for shots herself, but (HURL)
The neighbor kids are why she's not alive.
Their parents were convinced that a vaccine
Would be much worse than death on needless scales,
And so this bug broke out again. "Obscene"
Is not a strong 'nough word for these sad tales.
Autism is a horror, yes it's true,
But vaccines do not cause it, K? Thank you.