One of the fears of many people in relation to covid has been that the immunity that develops after infection is so short lived that the infection will just keep going around and around and re-infecting everyone (until everyone is dead, I assume).
“Only a minority of people in Sweden have antibodies, so they can’t have herd immunity!”
That is the most common argument I’ve been hearing for why Sweden can’t have achieved herd immunity. This is in spite of the fact that the rates of hospitalizations and deaths have dropped continuously since the peak in April, and are now stable at basement levels.
In my previous post on the covid pandemic I mentioned that the body’s main defence against viruses is T-cells, not antibodies, and that the only reason we test for antibodies instead in clinicial practice is because it is easier and cheaper. I also ventured a hypothesis that the levels of population immunity are much higher than is being found in the antibody tests, and that this is because lots of people who don’t have antibodies do have covid specific T-cells. It turns out that this hypothesis is supported by new evidence.