ASK A DOCTOR. Seriously, that should be the default for any medical question. If you're worried that the doctor won't have a Bayesian perspective, well, go see one anyway. They're not going to force you to get the shot, and you'll get the information necessary for you to do the Bayesian calculation.
There's an open thread for this kind of thing. Also, there are plenty of people online with actual legit medical training. It would be better to ask them than us.
I hope you don't die horribly. :-)