not to the original poster, but rhetorically, why does it matter if you lose the antibodies if you had no symptoms when you got it and presumably will have no symptoms if you get it again?
No mention of T-cell immunity which might last for a long time.
Supposedly those that are getting it a 2nd time are getting it worse.
Makes sense.
It may not matter to YOU, but once you lose those antibodies you can be infected again and transmit it to other people. Which you might not notice if your body doesn’t exhibit the symptoms.
It’s also something that argues against us being able to easily achieve herd immunity against this thing. If half the herd’s immunity expires before the other half of the herd can get immunity, then you can never achieve it.