That's great news! Maybe they'll test them better in future.

I'm still taking them. Think of how many people take vaccines and don't get ill, and don't get the illness.

I put together a simulation for you, using Nicky Case's Emoji simulation engine. This should explain it. Click next to a group of unimmune people to vaccinate them.

Since the simulation is so small, I put in an unsafe, mostly-effective vaccine; you will see the vaccine making people ill, to a much greater extent than happens in real life. (Orders of magnitude of a higher extent.) The illness is also pretty fatal, but not too fatal to spread to literally everyone in the simulation.

You'll also see the immune people catching the illness. You'll see them dying. And yet them being immune is better than the alternative. See how dangerous and ineffective a vaccine can be and still be better than the alternative? Real-world vaccines are safer and more effective than that.

Feel free to share it with other people, if you find it helpful. The code's a bit hackish and sporadic (you can see it by removing the "edit" parameter).