Even a flattened curve may be a disaster

Joscha Bach writes:

You have all seen a version of this curve of COVID-19 case loads by now:

What all these diagrams have in common:

1 They have no numbers on the axes. They don’t give you an idea how many cases it takes to overwhelm the medical system, and over how many days the epidemic will play out.

2 They suggest that currently, the medical system can deal with a large fraction (like maybe 2/3, 1/2 or 1/3) of the cases, but if we implement some mitigation measures, we can get the infections per day down to a level we can deal with.

3 They mean to tell you that we can get away without severe lockdowns as we are currently observing them in China and Italy. Instead, we let the infection burn through the entire population, until we have herd immunity (at 40% to 70%), and just space out the infections over a longer timespan.

The lack of numbers is the big issue. He does some estimates for the US. Basically they are:

  1. 924,000 hospital beds in the US
  2. 100,000 ICU beds of which 30,000 might be available
  3. 170,000 ventilators available
  4. 20% of COVID-19 cases require hospitalisation
  5. 6% of COVID-19 cases require a ventilator
  6. Range for infection rate is 40% to 70%, assume halfway 55%
  7. That means 180 million infected in US
  8. Those who need ventilators stay in hospital for four weeks

This then produces this graph:

That line at the bottom is the number of respirators available. At the peak three million people will need 170,000 respirators.

So even if you flatten the peak of the curve by two thirds you’ll still have 830,000 people in the US needing respirators who can’t get them.

To not have the number of patients needing a respirator exceed those available, you need to spread the curve over 10 years, instead of one.

Now this is ballpark estimates. It is now from a health authority. But what it does show is that we should not think flattening the curve by itself won’t still lead to huge numbers not being able to access necessary hospital care.

The model is quite sensitive to the length of the stay in the ICU. If we get that down, fewer people will need these resources simultaneously, and the peaks of the curves will come down. We may be able to fight the inflammation during pneumonia, and reduce the number of critical cases. The available medical resources will increase over time to deal with the need. Regulations will be dropped, new treatments will be explored, and some of them will work. At some point in the near future, we may have to blow into a tube before we enter an airplane or an important public building, and a little screen tells us within seconds if our airways hold COVID-19, H1N1 or the common flu. But the point of my argument is not that we are doomed, or that 6% of our population has to die, but that we must understand that containment is unavoidable, and should not be postponed, because later containment is going to be less effective and more expensive, and leads to additional deaths.

Now containment is not self-quarantine, it is far more than that:

There will be some countries that do not have the necessary infrastructure to implement severe containment measures, which include widespread testing, quarantines, movement restrictions, travel restrictions, work restrictions, supply chain reorganization, school closures, childcare for people working in critical professions, production and distribution of protective equipment and medical supplies. This means that some countries will stomp out the virus and others will not. In a few months from now, the world will turn into red zones and green zones, and almost all travel from red zones into green zones will come to a halt, until an effective treatment for COVID-19 is found.

Flattening the curve is not an option for the United States, for the UK or Germany. Don’t tell your friends to flatten the curve. Let’s start containment and stop the curve.

I’m hoping this isn’t necessary but hope is not a good basis for decision making. The numbers are compelling.

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