I think there's a big motte and bailey https://en.wikipedia.org/wiki/Motte-and-bailey_fallacy thing going on with Zero COVID, and whenever anyone says they are in favour of #ZeroCovid for the UK they need to explain whether they mean literally zero, or just a small number.

Brief non-technical maths diversion. 2 times 2 is 4. 2 times 2 times 2 is 8. 2 times 2 times 2 times 2 (four times) is 16. About now, we get lazy, and start writing 2^4 to mean "2 to the power 4" (2 multiplied by itself 4 times). 2^5 is 32. 2^6 is 64. 2^10 is 1024.

You can think of a ladder of numbers, doubling each step, and the key thing is that with coronavirus, because (under fixed level of lockdown) we expect numbers to be multiplied by the same amount each day, each step will take the same amount of time to climb down.

We can look at UK cases, 7 day average by specimen date.

On 5th Jan, it was 59,041. Now, 2^16 is 65,536, so close enough, we can say we were standing on Step 16 of the ladder on 5th January.

Step 15 is 2^15, or 32,768. The 7 day average took us below that on the 21st Jan, so it took us 16 days to go down a step.

Step 14 is 2^14, or 16,384. We're not there yet, but another 16 days would take us to about today, so optimistic we'll be there soon.

But at some stage we need to decide the level at which we can live with this. We got down to 500ish in the summer, but we were doing 20% of the tests we are now. So maybe the figure is a thousand? Step 10 is 2^10, so that means 6 steps down, or 3 months' lockdown at current rate.

Or maybe you take the Independent SAGE position that the arbitrary figure of 67, or 2^6, is the right one to decide the virus is under control? 4 more steps means two more months, or 5 months' total lockdown.

But the point is, this still isn't zero. There's no particular law that says 2^6 is a natural number where we keep at equilibrium. So maybe we need to keep driving it down? So how far, and how long does that take, and what do we have to do to stay there?

However, surely at some stage we need to have a grown-up discussion about QALYs, laws of diminishing returns and other costs of lockdown, particularly in the context of the fact that we expect IFRs to drop and immune percentages to rise soon due to vaccination?

Hopefully this will happen soon, because it's depressing how much of the oxygen has been sucked out of that room by the smiley face morons parroting things they learned off YouTube videos about "45 PcR cYcLeS" to argue 4,000 hospitalizations a day wasn't a problem. Rant over.