[BurningFrog]

Not really. A vaccine is never 100% effective.

[Wowfunhappy]

I thought the Smallpox vaccine was, or basically was? That's how we were able to eradicate Smallpox by giving everyone the vaccine.

[BurningFrog]

You only need to the vaccine to lower the spread to an unsustainable level, and the disease will fizzle out.

The challenge for smallpox was more to do it in every remote corner of the planet.