Being over cautious? 54 million people had it, a handful twice, some we can name.
You can spread it from antibodies? Something i'm not understanding...
Looking at the current number of infections I don't think we are being nearly cautious enough.
A few years from now we will understand better but for now 'If you have been in contact with a positive case you isolate, no excuses' seems reasonable to me.
Yes. A handful of people have caught it twice (two positive tests many months apart).