Saturday, March 28, 2020

debating the virus

Exponential growth

Eight days ago I sent some figures to a friend saying that if exponential growth continued, doubling every 4 days, then we would have 3,200 corona virus cases in Australia today (28/3)

Our government website, Coronavirus (COVID-19) current situation and case numbers, says that yesterday, 27/3 at 3pm there were 3,166 confirmed cases, so we are still on an exponential growth path.

From their graph the doubling looks roughly like this:

date   total cases
9/3        100
12/3       200
16/3       400
20/3       800
24/3      1600
28/3      3200

Extrapolating that further if the current exponential growth continues
1/4       6400
5/4      13,000
9/4      26,000
13/4     52,000
17/4    104,000
21/4    208,000
25/4    416,000
29/4    832,000

Nearly a million cases by the end of April. These figures, understanding exponential growth, explains the importance of an immediate lock down or hibernation.
Click on the image for a larger view. The lower reported figures in the last two days could be a positive sign or could be a delay in reporting.

update (new graph 4 days later, March 31st):
Hard to read at that size but click on the image for a larger view. Note that the reported figures for each day creep up after the day has passed. New cases on 26/3 are 280 on the first graph and jump to 360 on the second graph. New cases on 27/3 are 175 on the first graph and jump to 370 on the second graph.

Nevertheless, the curve has flattened a little. If doubling every 4 days had continued we would be up to 6,400 cases tomorrow (1/4) and our current figure of 4,359 (today, 31/3) is well below that.

The debate in Australia and world wide is divided between:
  • Those screaming for an immediate lockdown (#lockdownAustralia, Dr Greg Kelly) and critical of Scott Morrison for his ambivalence and mixed messages.

  • Those saying that the danger of this virus has been exaggerated, that the Infectious Fatality Rate is roughly 2 deaths in a 1000 cases (eg. Global Covid-19 Case Fatality Rates:
    Our current best assumption, as of the 22nd March, is the IFR is approximate 0.20%... and later .... Current data from Iceland suggests the IFR is somewhere between 0.05% and 0.14%
  • Those saying that it is more important to keep the economy going and that a lockdown will have worse consequences than attempting to contain the virus (eg. The Corona Dilemma)

  • Those saying that the capitalist system is inherently anarchic or unstable and that this event will push us into an economic downturn worse than the 1930s Depression (A Greater Depression?, People’s Forum: Economic Lessons for 2020)
My views:
I'll keep this brief since still reading and assessing:
(1) What should we do immediately? I agree with lockdown simply because there are empirical cases of
(a) it can overwhelm health systems as in Italy
(b) Some countries through lockdown have succeed in flattening the curve (China, South Korea, Japan, Hong Kong, Singapore)

(2) There is a lot we don't know about this particular virus, we need to learn a lot more. eg. as far as I'm aware we don't know whether young people with the virus who are asymptomatic pass it on to others. Of course there are a lot of experts working hard on this right now.

(3) What does the health endpoint look like and how long will that take? Can a vaccine be developed in less than 18 months? Apart from a vaccine what other end points are possible?

(4) Economic and political futures. The left has been lost for many years. There seem to be a few thinkers with a clue (eg. Michael Hudson, David Graeber) but no coherent movement to lead us out of this mess.

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