system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: live vaccines

My daughter is having her vaccinations soon and it struck me that I have no idea how live vaccines work. I did some research but the information I found was either super simple or way over my head.
gpt
A live vaccine is like a neutered, weakened form of the virus.

Think of it like training someone to fix a car. You don't give them a Rolls-Royce or Ferrari for their first repair job. You give them something smaller, something simpler, so they can get used to it. Once they know how to do it, then you can let them fix the more important stuff.

The live vaccine does the same thing. It gives a weaker form of the virus to the body. Since it's weak, the immune system has the time to recognize that it's a virus and learn how to defeat it (start producing antibodies for the virus) before the body takes much damage. Then, once the real virus comes along, the immune system is ready to fight it off.