human
I've heard that it's possible to make your own vaccines. Is that true?
assistant
It is certainly possible, but there are some important safety considerations you should be aware of before attempting this. The first thing to understand is that vaccines contain a very small amount of the actual virus or bacteria being vaccinated against. This is necessary because if too much of the vaccine itself was given, it could cause an allergic reaction. So when making your own vaccine, you would need to isolate and grow the specific pathogen in question. You would then need to purify the vaccine material so that all traces of the other viruses and bacteria have been removed. Then you would need to determine how much of the vaccine material to use, and finally you would need to test the vaccine on animals to ensure that it is safe and effective.