[Myrddin]

The only good case that you can make for antibodies against COVID-19 is the cases of convalescent plasma being used to rescue 3 of 5 persons who were in ICU and not making progress on the antiviral regimen. 3 quickly recovered when given 400 ml of convalescent plasma.

Given all the other strains going around (at least 8 at the last count), you're likely to encounter one of the other ones in spite of winning the battle the first time.

Link to case

[Tolerance Sucks Rocks]

As I understand it, this coronavirus, like others, is actually quite stable. Some strains may be more vicious than others, but once you’ve had one, you’d likely be partially immune to most of the other ones.