But that study only looks at people with antibodies. There have been a number of studies showing that some people with Covid don't develop anti-bodies but use T-cells to fight off the infection. I linked to an article yesterday from a Swedish doctor. He said:Originally Posted by Mike T
"The media have been proclaiming that only a small percentage of the population have antibodies, and therefore it is impossible that herd immunity has developed. Well, if herd immunity hasn’t developed, where are all the sick people? Why has the rate of infection dropped so precipitously? Considering that most people in Sweden are leading their lives normally now, not socially distancing, not wearing masks, there should still be high rates of infection.
The reason we test for antibodies is because it is easy and cheap. Antibodies are in fact not the body’s main defence against virus infections. T-cells are. But T-cells are harder to measure than antibodies, so we don’t really do it clinically. It is quite possible to have T-cells that are specific for Covid and thereby make you immune to the disease, without having any antibodies. Personally, I think this is what has happened. Everybody who works in the emergency room where I work has had the antibody test. Very few actually have antibodies. This is in spite of being exposed to huge numbers of infected people, including at the beginning of the pandemic, before we realised how widespread Covid was, and when no one was wearing protective equipment."
Obviously the author is talking about Sweden and they are probably further down the line than we are but still it is likely that a lot more have had the virus in this country than the Imperial Study estimates.
