This is worrying. The bastard Corona could just continue to mutate into new strains, making the immune system antibodies and vaccines irrelevant. (A bit like seasonal flue)...
Not much data, but the virus may be around for the long haul.
The idea is that some countries that might have got the weaker A strain letting them develop antibodies for B and C strains- and this is why some countries the East have been less hit. That Italy may have got the C strain which is the worst one.
However, who knows how many strains will happen, so A immunity may be irrelevant to D, E, F.... strains.
