Originally Posted by
trueblu
I'm going to _try_ to be less active on this thread: this thread was extremely valuable over the last two months since COVID-19 was really such an unknown...and most governments were minimising threats...I think that will become less and less the case as the pandemic progresses.
Re: potential outcomes,
this link about pandemic preparedness from Johns Hopkins, adapted from an influenza document, really tells the stark reality. There are two scenarios: 1968-like and 1918-like. Even the 1968 scenario is scary, but I think we're actually more like the 1918 scenario.
Although I agree that we don't know the denominator of true infected, Diamond Princess is the best 'contained' point outbreak we have: the demographics are skewed, to be fair, since it was a much older than average population. But the number of asymptomatic individuals appears to be ~50%, it _may_ be a bit higher with a younger demographic, but I think the mortality rate is going to be well above 0.2%, and could well be 1% or even slightly higher, and that is under optimal care scenarios. The hospitalization rate is the biggest concern, as I and others have said all along: this has serious implications for _all cause mortality_. And I don't think this rate will be under 3%, which is just too high for us to cope with.
…...
To piggy back on this, the most accurate and complete data sets we seem to have are from S. Korea, the Wuhan Princess (albeit skewed to older), and to a lesser extend, published data from Chinese samples, like this
one. The data suggest mortality rates around 0.7-0.8% for S. Korea (0.7% now, and likely 0.8% as some more of the critical will die), 1-2% for WP (1% now, and with another 20% from the critical cases dying, it will go up to 2%). These under optimal health care conditions.
If we look at the Chinese data, 14% of the cases were severe, and 5% were critical. From the critical, 49% died, leading to an overall fatality rate of 2.3%
What does this mean for the rest of the world? If this is relatively contained, and some decent health care is maintained, the true overall fatality rate is likely to be around 0.5-1%. However, if it becomes widespread and infects more people and starts overwhelming the health care systems, the overall fatality rate will likely be 2.5 - 5% of those infected, and may even go higher.
Practically, what that means, is that the 14% of the overall cases who will be classified as severe would have to ride this in their homes (or warehouse-style make shift hospitals/isolation units). From the 5% which will be classified as critical cases, some/few may have access to ICUs or other hospital care and survive, or worst case scenario almost all 5% perishes. And then the question is how much spread there will be, with some estimates ranging between 10-70% of the world population, which will affect the raw numbers, and in turn, the overall fatality rate.
So, good scenario likely around 0.5% fatality rate, bad scenario 2.5 - 5% fatality rate, and the raw numbers will vary, based on how much transmission will occur.