Worst case scenario of 80% population infected

[crazydiamond222]

Does anyone know how this worst case scenario of 60-80% infected was calculated and how likely it is?
www.google.com/amp/s/amp.theguardian.com/world/2020/feb/11/coronavirus-expert-warns-infection-could-reach-60-of-worlds-population.

The virus is said to have peaked in China with less 0.01% infected (80,000 in pop of 1.3 billion). Even accounting for lots of undiagnosed cases and a couple of months of trailing off this is signifantly lower than what is projected in this scenario. It would have to be assumed that only around 1 in 5000 cases in china have been diagnosed for the numbers to stack up.

Is it becuase the UK govt and other countries are not imposing isolation to the extent of the Chinese? Can anyone explain?

There was an explanation for this on the radio programme PM. They are planning for the worst case scenario, assuming that this will not be reached. The person interviewed explains that a virus like this rushes in and affects new people very quickly but can’t ever reach 100%. They also explain why closing schools would cause more problems than it solved - not least because of health workers who would have to stay at home. Starts about 9 minutes in:

www.bbc.co.uk/sounds/play/m000fvvt

In China the state steps in and issues whole areas to be in lockdown. Most other countries would not tolerate this. I also heard that in China people who were tested had to wait 10 days for results, but if they died before they got results back those people not counted in death toll from covid because not officially diagnosed whilst alive. So true death toll much higher in China. Compare that to in South Korea results available much quicker and spread much higher.

Thanks for the link to the radio programme. The main take from this though is that they have not got a clue on what numbers are likely to be but are preparing for the very worst scenario based on the theory of hed immunity with no reference to the experience in china. en.m.wikipedia.org/wiki/Herd_immunity

I think the 80% infection rate has been misreported. The following document suggests that 4 in 5 cases are not diagnosed so based on this the infection rate in china is likely to be around 0.05% at present (i.e 5 x 0.01%). Given another 2-3 months of declining cases it could double to 0.1% in China. It may of course be considerably higher in the UK if we don't shut down cities etc but I would doubt it would be anywhere near 80%
www.cato.org/blog/misleading-arithmetic-covid-19-death-rates