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Coronavirus: The Hammer and the Dance

What the Next 18 Months Can Look Like, if Leaders Buy Us Time

Tomas Pueyo
Mar 19 · 29 min read
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1. What’s the situation?

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2. What Are Our Options?

Measures in Spain and France

Measures in the US and UK

Option 1: Do Nothing

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This fantastic epidemic calculator can help you understand what will happen under different scenarios. I’ve pasted below the graph the key factors that determine the behavior of the virus. Note that infected, in pink, peak in the tens of millions at a certain date. Most variables have been kept from the default. The only material changes are R from 2.2 to 2.4 (corresponds better to currently available information. See at the bottom of the epidemic calculator), fatality rate (4% due to healthcare system collapse. See details below or in the previous article), length of hospital stay (down from 20 to 10 days) and hospitalization rate (down from 20% to 14% based on severe and critical cases. Note the WHO calls out a 20% rate) based on our most recently available gathering of research. Note that these numbers don’t change results much. The only change that matters is the fatality rate.

How Should We Think about the Fatality Rate?

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If 5% of your cases require intensive care and you can’t provide it, most of those people die. As simple as that.

Collateral Damage

What happens if you have a heart attack but the ambulance takes 50 minutes to come instead of 8 (too many coronavirus cases) and once you arrive, there’s no ICU and no doctor available? You die.

If the coronavirus is left to spread, the US healthcare system will collapse, and the deaths will be in the millions, maybe more than 10 million.

Unbridled coronavirus means healthcare systems collapse, and that means mass death.

Option 2: Mitigation Strategy

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Herd Immunity and Virus Mutation

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The best way for this virus to mutate is to have millions of opportunities to do so, which is exactly what a mitigation strategy would provide.

Option 3: Suppression Strategy

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All the model parameters are the same, except that there is an intervention around now to reduce the transmission rate to R=0.62, and because the healthcare system isn’t collapsed, the fatality rate goes down to 0.6%. I defined “around now” as having ~32,000 cases when implementing the measures (3x the official number as of today, 3/19). Note that this is not too sensitive to the R chosen. An R of 0.98 for example shows 15,000 deaths. Five times more than with an R of 0.62, but still tens of thousands of deaths and not millions. It’s also not too sensitive to the fatality rate: if it’s 0.7% instead of 0.6%, the death toll goes from 15,000 to 17,000. It’s the combination of a higher R, a higher fatality rate, and a delay in taking measures that explodes the number of fatalities. That’s why we need to take measures to reduce R today. For clarification, the famous R0 is R at the beginning (R at time 0). It’s the transmission rate when nobody is immune yet and there are no measures against it taken. R is the overall transmission rate.

Under a suppression strategy, after the first wave is done, the death toll is in the thousands, and not in the millions.

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3. The Value of Time

What if you were about to face your worst enemy, of which you knew very little, and you had two options: Either you run towards it, or you escape to buy yourself a bit of time to prepare. Which one would you choose?

Lower the Number of Cases

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Source: Tomas Pueyo analysis over chart and data from the Journal of the American Medical Association

Understand the True Problem: Testing and Tracing

Right now, the UK and the US have no idea about their true cases. We don’t know how many there are. We just know the official number is not right, and the true one is in the tens of thousands of cases. This has happened because we’re not testing, and we’re not tracing.

Build Up Capacity

Lower Public Contagiousness

Understand the Virus

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Find Treatments

Understand the Cost-Benefits

4. The Hammer and the Dance

The Hammer

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The Dance

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The Dance in Successful Countries

The Dance of R

The ROI of Social Distancing

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This is for illustrative purposes only. All data is made up. However, as far as we were able to tell, this data doesn’t exist today. It needs to. For example, the list from the CDC is a great start, but it misses things like education measures, triggers, quantifications of costs and benefits, measure details, economic / social countermeasures…

Conclusion: Buy Us Time

Share the Word


Thanks to Tito Hubert, Genevieve Gee, Pierre Djian, Jorge Peñalva, and Matt Bell

Tomas Pueyo

Written by

2 MSc in Engineering. Stanford MBA. Ex-Consultant. Creator of applications with >20M users. Currently leading a billion-dollar business @ Course Hero

Tomas Pueyo

Written by

2 MSc in Engineering. Stanford MBA. Ex-Consultant. Creator of applications with >20M users. Currently leading a billion-dollar business @ Course Hero

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