“Asymptomatic Carriers”

I’m like many people, trying to read through the literature, and acquaint myself with a field I’ve never really had much interest in.

As I understand it, a viral infection is a virus getting into your system somehow, they using your “biological energy”, for want of a better phrase, to replicate.  Fighting off this intruder takes up a lot of body resources, as does the virus, which is what makes you “sick”.

If you think about it, though, a healthy immune system that works decisively and quickly is the equivalent to a vaccination for every known disease, and most unknown diseases.

Here is what I am wondering: if someone tests positive for COVID-19 antibodies, is it really even accurate to say they “had” or “have” it?  Does that not just mean that their immune system is doing what it is supposed to do?

If you tested any of us at random for 50 different diseases, would we not have antibodies for some of them at all times, since we are fighting them off successfully?

I don’t know the answer.