Well, I don’t have an insight into China’s efforts, even though they are reporting very few new cases. On the other hand, we do have some statistics from South Korea.
- They have a population of 51,709,098.
- They have tested over 200,000 people
- And I gather are testing more that 10,000 a day
- This is considerably more than what the U.S. has done.
- They have more than 8,000 cases (8,086 as of noon 3/14/20).
- They have 72 deaths (as of noon on 3 /14/20)
So……
- They have tested over 0.39% of their population (they have tested less than 1% of their population)
- Of the tested population around 4% have coronavirus
- Of the population with the virus, 0.89% have died (less than 1%).
Now working backwards to the U.S. situation:
- We now have 47 deaths (as of noon).
- Does this mean that we have over 5,000 cases in the U.S.?
- Does this mean that we should be testing more than 1,250,00 people?
- I gather we are finally on the path to doing that…but not sure how long it will take.
As far as we know, North Korea has no cases. This is hard to believe as the border between North Korea and China is fairly porous and there are a significant number of North Koreans living and working in China. But, officially, there are no reported cases in North Korea.
“Does this mean that we have over 5,000 cases in the U.S.?”
No. That means you had around 5000 cases three weeks ago!
You have very likely seen the UK government expert two days ago on TV: They estimate 5000-10000 cases in the UK, with 500 detected.
How to generate such numbers?
1) average time between infection and dead 3 weeks
2) mortality 0.5% – 1%.
3) A patient is infectious between day two and day ten, afterwards he is in ICU or has enough antibodies, which kill the virus.
4) In the 7/8 days an infected person infects on average three others.
With 1% mortality 1 dead person today means 100 infected persons three weeks ago (0.5% mortality means 200 persons). Each of the 100 infected persons produces 3^3 = 27 new infected person within three weeks.
Therefore, 50 dead patients within a few days mean you had as worst case 5000 infected people three weeks ago, now ~150000.
If we assume that the WA cases are bad luck (one institution with many elder persons) and only work with 20 dead patients from 8 hotspots, then we get at least 2000 infected people three weeks ago and ~50000 infected people today, of which 2500 (=2%) are actually diagnosed.
A useful point.