I have a very basic understanding of how antibodies work and understand that having Covid antibodies may offer some level of immunity to Covid, but my question is if you had Covid and obviously developed antibodies but have since been tested for antibodies and no longer have them, does this mean you are back to square 1 as far as your immune system dealing with Covid infection? Or does your immune system "learn" to fight Covid and learn to produce antibodies, so that theoretically someone who had Covid and recovered previously would be in a better position to deal with a 2nd infection even without antibodies?


*edit to say I understand that there can't possibly be enough time to have studied Covid recoveries and efficacy at combating 2nd infections, so my question wasn't meant to be specific to Covid, just virus immune system defense in general. I.e. if you have had flu, you develop antibodies, but after some period of time I guess they go away, but is immune system better able to deal with subsequent flu infections even without anti bodies?