Your imaginary experts discrediting the concept of immunity are idiots.
Not the idea of
immunity. The idea of
herd immunity forming a public strategy for this virus. There are so many unknowns for a novel coronavirus (keyword: novel) that it represents just about the least cautious approach possible. Estimates for the percentage of people required to develop immunity in order for herd immunity to act as an effective bulwark vary hugely, but are usually around 60 - 65% (and no, I'm not going to listen to what you think the immunity rate would need to be; I'm going to be taking numbers from the experts).
We don't know the mortality rate of the virus for certain, but early studies put it around 2 - 3%, making use of the limited data available. So, an intentional herd immunity strategy in the US could therefore be aiming for 60 infection (about 196 million people), with 2 or 3% dying, coming to... just under 4 million deaths. Only, it would probably end up being a great deal higher, because such a rush would inevitably overwhelm the health services.
The enormous and unnecessary death toll involved in pursuing herd immunity
as public policy is almost certainly the reason the UK government abandoned that doomed avenue.
I mean, that's it. That's the post. Statistics in this situation don't mean a whole lot in a contextual vacuum. If one just looked at numbers of raw tests and tests per capita, and positivity rate, you'd think South Korea would be a Fallout hellscape by now dominated by COVID super mutants. Clearly that is not the case.
Thankfully, we do have some context.
The context being that I was promoting the use of the positivity rate specifically to judge whether the rise is primarily attributable to increased testing, as V.P. Pence argued. For that purpose, it's not perfect, but it's about the most apt metric we have.