[wesleywt]

Its an attenuated vaccine, which means it was grown to be weaker then the wildtype by growing it in non-human cells making it more specific to what it was grown in. I have never had chickenpox because i had the vaccine. If had chickenpox as a child you were extremely unlucky because its completely unnecessary.

[hedgehog]

It depends how old / where, the US didn't start vaccinating widely until around 30 years ago.

[stvltvs]

We didn't have this new-fangled chickenpox vaccine during my Gen-X childhood.