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Michael Droy

Hindsight is still a long way ahead of us.
Is destroying the economy the right solution? - no one has a clue - or rather the argument is largely based on QALYs and no one is talking about QALYs so either the calculations aren't being done or more likely they are too brutal for politicians to dare use them.

No one has any real data.
Death rates are death with Covid-19 tested, not death by Covid-19 and certainly not all deaths with Covid-19 which for all we know may go back to last summer or before.
Infection rates are only infection rates of patients with symptoms who demand a test - most people with symptoms are expected to self-isolate and shut up. We don't know infection rates at any place or any time within a factor of 10 (other than emergency sites like Wuhan where the guessing range is down to a factor of 2).
Outbreaks are defined by hospitals overwhelmed rather than infection rates, and tests are only common after outbreaks.
On a top down level the evidence across countries is that Covid-19 has not lead to more deaths overall (though that does not mean it can't be shown at local levels).

And likewise there is no proper data that confirms that Wuhan or China is over it. (In Wuhan the economy leading to much lower levels of pollution may have been a major factor absent from even the testing data)

Suppose you attempt a proper investigation. Assume 0.1% infection. You'd need 100k randomly controlled tests to get 100 cases - nobody is able to do that many tests - and certainly not of a truly random sample.

There is supposedly an anti-body test - though we have no idea when this will be widely available of if it will work. If it is cheap enough to uncover all those who have got over the virus it will tell us real info if used in scale. Then we will have data.

Noah Silbert

You're right that hindsight feels deceptively clear, and some arguments about any particular country's (lack of) response is based on this, but it's also worth noting that there were a lot of people arguing for an early response (very) early in the process, i.e., without the benefit (and false clarity) of hindsight.

Also, I don't understand what you mean by "In fact, one can say Country B's action validated Country A's earlier decision to stall." How does Country B's later decision to stall validate Country A's earlier decision to stall?


NS: What I mean is: by choosing to follow a similar path as country A, country B basically said, "Well, A is right. Even with the extra time and data, we will follow A's lead and do the same thing."
So in this sense, country B has validated what country A did (at least up to the time Country B had to decide). Now, it is still possible that both countries made bad choices. We won't know until later by comparing them to country C that chose a different path.

Antonio Rinaldi

Read on twitter:
Everything we do before a pandemic will seem alarmist. Everything we do after will seem inadequate


The problem with these arguments is that everything that has happened has been perfectly predictable since early February. It was known from Chinese studies that the baseline transmission rate (number of new cases that each case generates) was probably about 2.5 but could be higher. It has since been shown to be about 3 in most Western countries but higher in Spain and Italy. Social life changes things. That means without interventions there is a doubling of cases about every 3 to 4 days and that is what happened in Wuhan until their lockdown took effect. We also knew that mild cases were difficult to distinguish from influenza, so unless someone actually does a lot of testing, nobody has a clue how many cases there are until people start dying in unusual numbers. So it was known that unless we intervened in some way there was going to be a huge epidemic. The doubling every 3-4 days is repeated in every country in the period when the epidemic is uncontrolled. Doublings are faster in the early period when the public health people are catching up, so the number of real cases doesn't increase a that rate only the observed. We also knew roughly the effectiveness of interventions and the answer is reasonable but not enough. What is needed is good testing and case tracking. It can work because South Korea and Taiwan have made it work. In Australia it seems to be working with a partial lockdown and we haven't implemented some of the control measures, probably because of political reasons. One of the characteristics of successful Asian countries seems to be the belief that things are done properly. Old wealthy nations generally get away with doing things poorly.


Ken: "Perfectly predictable" is according to your assumptions though. Someone with different assumptions may disagree. I was pointed to some projections for the U.S. (not January but yesterday's update) and its estimate for peak hospital beds needed has a confidence interval from 2K to 200K. Plus, the Chinese studies were not available till recently. What would you have said if the situation in China were not under control today? I do agree with your last point. Loss aversion is real. The richer a country, the more there is to lose by shutting things down. The other thing one can infer is how much business interests run the respective governments.

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