Saturday, March 14, 2020

Covid-19: Comparing US to Rest of the World

12 comments:

Layzej said...
This comment has been removed by the author.
David in Cal said...

If I understand this chart correctly, it seems to say that the US is doing a lot better than the Rest of the World, in terms of per capita cases and per capita deaths. I suppose this makes sense, given how bad the problem was in China. Am I missing something?

Cheers

Entropic man said...

David in Cal

The vast majority of both cases and deaths occurred in China's Hubei province over the past two months. They are coming out of their epidemic with few new cases and deaths.

The US is in the early stages of their epidemic, with a very slow rate of testing. The number of cases and number of deaths due to the coronavirus are therefore both being underestimated.They will get a LOT more numerous over coming weeks.

Your "doing a lot better than the rest of the world" is an illusion.

David in Cal said...

Entropic - you make a good point. The number of cases will get a lot more numerous, as the virus spreads and due to more testing. Of course, that's true of most other countries as well. Time will tell whether the US continues to look better than the rest of the world. In particular, time will tell whether the US continues to look better than Europe.

As you say, the US is in the early stages of the epidemic. In other words, it has spread more slowly here than, say, in Europe. Why has it spread more slowly? Do you buy Trump's claim that his early cutoff of people from China is the reason the US is doing so much better than Europe? If not, to what do you attribute this difference?

Below is pasted part of a chart, as best I could. The difference in Total Cases/Million Population between the US and Europe is enormous. E.g.,

Spain 135, Italy 348, Germany 54, France 68, Switzerland 158, US 7.5.

The full chart is at https://www.worldometers.info/coronavirus/#countries


Country,
Other Total
Cases New
Cases Total
Deaths New
Deaths Total
Recovered Active
Cases Serious,
Critical Tot Cases/
1M pop
China 80,824 +11 3,189 +13 65,573 12,062 3,610 56.2
Italy 21,157 +3,497 1,441 +175 1,966 17,750 1,518 349.9
Iran 12,729 +1,365 611 +97 4,339 7,779 151.5
S. Korea 8,086 +107 72 +5 714 7,300 59 157.7
Spain 6,315 +1,083 193 +60 517 5,605 293 135.1
Germany 4,525 +850 8 46 4,471 9 54.0
France 4,469 +808 91 +12 12 4,366 154 68.5
USA 2,499 +252 55 +6 49 2,395 10 7.5
Switzerland 1,375 +236 13 +2 4 1,358 158.9
UK 1,140 +342 21 +10 18 1,101 20 16.8

Cheers

Entropic man said...

The US and The UK, along with a number of other European countries, are increasing cases by about 25% each day.

This is the exponential growth phase. It will be a while before we can tell who is doing best.

The good standard so far is China, which managed to keep the number of cases in Hubei province below 2% of the population.

To match that, the US would need to top off at 6 million cases and the UK at 1.4 million.

With cases doubling every 5 days, we'll have a better idea of relative success in 2 months. Ask me again in mid-May.

Ned said...

This is a good summary of the situation so far in the USA:

The Trump administration’s botched coronavirus response, explained

This graphic is especially impressive as a data visualization:

A snapshot of early Covid-19 testing per capita

Entropic man said...

There's a complication.

The UK is following a herd immunity strategy. They are not trying to minimise infections, just to slow the rate enough to allow the health services to cope. The aim is to get about 80% of the population immune before next Winter. That way it will not recur.

Not sure yet, but the US will probably try for minimum cases in the short term, which may mean a second big jump in cases when they relax.

Layzej said...

Why has it spread more slowly? Do you buy Trump's claim that his early cutoff of people from China is the reason the US is doing so much better than Europe?

It seems like it should have, but Canada and Mexico did not shut down borders and are slightly better off than US. It's a mystery to me.

David in Cal said...

Layzej - The US probably has many more foreign visitors than Canada or Mexico.

Layzej said...

I wouldn't think that's true per capita. There is not a more international city than Toronto, and Vancouver has a huge Chinese population.

The stats I'm able to find show 80 million visitors to USA in a year, and 21 million visitors to Canada in 11 months.

That's over twice as many visitors per capita to Canada, but our per capita infection rate is slightly less than USA.

Ned said...

Any comparison across countries in raw number of cases has to account for difference in the rate of testing.

For example, Belgium has 8 times as many known cases per million as the USA, but has tested 13 times as many people per million. The UK has 2 times as many known cases per million, but has tested 15 times as many people per million.

If you test a higher percentage of the population, you will find more cases. If (like the USA) you make it very difficult for people to be tested, you will find very few cases.

In addition, comparing any one country to "the rest of the world" is misleading, because the world's statistics are heavily dominated by China, where the disease emerged first and peaked first.

The number of known cases does seem to be increasing faster in the cluster of Spain/Italy/Switzerland/France than in most other countries. Here's a chart showing the number of doublings of cases that occurred in each country over the past month:

https://i.imgur.com/phfjx33.png

Italy has had the most rapid spread during the past month, and China the least (the growth rate peaked earlier in China and has declined).
The USA is in the middle of the pack, along with the UK, Finland, and Germany.
Canada, Japan, and Australia have had slower rates of spread.

I'm not sure there is a nice neat story here, but it does seem like there's an arc of higher than expected rates of spread extending from northern Italy through Switzerland and France into Spain.

Doing this analysis has made me feel a bit more optimistic (or less pessimistic) about the situation in the USA. On the other hand, this comparison of testing vs cases is more disconcerting:

https://i.imgur.com/NHAkTmX.png

The US (along with Switzerland, France, Netherlands, and Italy) has an above-expected number of cases per test. That confirms that we are under-testing, and there are probably a substantial number of undetected cases out there waiting to be found.

Ned said...

Also, Trump's talking-points about his "travel restrictions" are mostly bogus:

The Facts on Trump’s Travel Restrictions

Condensed version:

(1) The "cutoff of people from China" was more of a "partial reduction" than a "cutoff"

(2) It wasn't a bold move going against the advice of experts

(3) It didn't face much opposition from others in the US

(4) Its effect was probably marginal

The reduction in travel from China may have delayed the spread of the virus in the US, but because the Trump administration didn't do anything significant during the extra time that was bought, it may not have reduced the spread of the virus at all. If the US had adopted aggressive countermeasures in late Jan/early Feb, that delay might have saved lots of lives. But we didn't so it didn't.