I got to thinking about this and Googled it. Unfortunately, yes, it can come back. Also, the vaccine is only around 50% effective. So maybe it wouldn't be worth it for someone who has a higher likelihood of having a bad reaction. And it scares the bejeebers out of me that I could still get it!

But it's true that they have medications that can help a lot once you have it. Seems the key is to contact a doctor ASAP because the window of opportunity is very small. Go to a store clinic if it's the weekend or evening...don't wait!