I have read articles where various immunologists and virologists discuss the fact that some people’s response to infection includes a lowering of abs after a while but that ab level would rise again quyickly upon reinfection or reexposure.I was horribly ill in early Feb 2020, with what are now recognized as Covid symptoms. I’ve never been so sick in my life. Lost my sense of taste for weeks. Cough that lasted over a month. Took forever to feel 100%.
Had a covid antibody test in summer 2020 and came back negative. I’ve always been confused by that.