system
Given the following post, respond as if you're commenting on Reddit:
human
Have our immune systems lost the ability to fight smallpox now that it is eliminated?
gpt
Depends what you mean by "lost the ability"

Your immune system will still attack the virus. Assuming you are not immunocompromised in some way then if you contracted small pox you would have about the same chance of surviving/dying from it as anyone in the past (assuming no supportive medicine and that you haven't previously contracted something like cow pox which was actually how the idea of vaccination came about, that's a different story).

If you mean does your immune system "remember" the virus and would it be already primed to fight it, unfortunately the answer is no, that is sadly not how the immune system works. You body must encounter a pathogen and overcome it to know how to fight it in future (or at least a pathogen very similar, which is the whole cow pox/small pox thing)