Herd Immunity.

In order to get herd immunity you need well over 70% of the population to have the antibodies. As estimates at present indicate less that 0.5% of the population have had it.
If the disease was left to take its course we would probably be looking at well over a million deaths. Then we would have herd immunity.
Even the Tories blanched at that death-rate.
This disease doesn’t burn itself out. It continues to spread where-ever it can just to a new host. In the absence of a vaccine the only way of controlling it is severe social distancing. That requires everyone distancing and washing hands and a very robust system of testing new cases , following up contacts and isolating.
We will not achieve any herd immunity until such time as we have a vaccine.
If people begin to relax and not follow social distancing we will have a major surge. If the NHS is overwhelmed many more will die because without critical care the disease will be fatal to a much larger percentage. That is the scariest part.
I’m in isolation. As a biologist I know how pandemics work. If they are not contained, like this one, then it will devastate a population. Britain and America have been pathetic! We should have prepared, tested, isolated and contained. We were ill-prepared and let it get out of control – hence the draconian measures needed to restore control.
Johnson, Bolsonaro and Trump have cost many tens of thousands of lives!