A) Of course people can be allergic to things in the meds, just like I can't take morphine, there are some people that are allergic to other things. This is not the fault of the drug companies.
B) Who ever in their right mind would think that they make you immune to something for life? Why would you have to get boosters if that were the case?
There's a big difference between being allergic to something and getting poisoned by toxic metals directly injected into your bloodstream.