I'm getting downvoted a lot on this and I'd love to know why. To be clear, I'm not for the anti-vax movement. My point is just to say that this topic is very similar to that movement.

How do you verify the content of a vaccine? It's not much different to using proprietary software. Yes, it seems to be good for us, but can you trust it fully without being able to verify it's contents and confirm that it wasn't tampered with along the way?

It's not reasonable to expect every individual to have the time, resources or expertise to personally run a full chemical analysis on every dose of vaccine or medicine that enters their body.

So... you don't. You don't verify it, because you can't. You can't verify all of science from first principles. You can't inspect every building you enter and verify that it meets code. You can't inspect every electronic device for NSA taps. You can't inspect all of your food, drinking water, or even all of the FOSS code you use. Society is too large, and the domains of knowledge and expertise that feed into it are too complex for any individual to fully comprehend.

You can't eliminate risk or trust from life. As far as vaccines go, you just have to trust that they work and are not likely to be poison and take the shot.