Thread by @shrikanth_krish

One of the key arguments of the alarmists in the Covid-19 debate has been around the stress that can be posed to ICU infrastructure in the coming months

Here's a thread to assess how warranted is this fear.

Let's start with this table -

Now let's start with the Corona virus situation as it exists in these two countries

Note that the ICU numbers below are my guesses. They may be off.

Now the "death" count reported in the above tables are incontrovertible.

But what can be questioned is the denominator - the # active cases

As testing is not comprehensive and wide, it is possible the active cases are being understated.

Now let's consider the "end game" for both countries

Here's one scenario for the peaks in both countries -

1% of population gets infected in US
0.2% of population gets infected in India

Lower in India given our population is significantly rural + hotter weather etc

This would translate to -

Peak infection count of -

3MM in US
2MM in India

Now if your "current" denominator of 27K for US and 330 for India are indeed accurate

It would mean infections will increase by 111x w.r.t today in US and 6000x in India

What does that mean in terms of cumulative ICU demand -
111K in US (1000 X 111)
90K in India (15 X 6000)

But this is a stock quantity. (cumulative figure)

People recover all the time from Covid. So at any given point, the ICU demand might be 30% of this -

111K X 0.3 = 33K
90K X 0.3 = 27K

We estimated the "slack" capacity in the two countries to be 11K and 2.8K earlier in the thread

So clearly the healthcare system would be overwhelmed!

But this is assuming your current "denominator" is correct.

Which it is most definitely not.

Now let's suppose you had more widespread (or atleast random) testing, and you have a more reliable assessment of infection rate -

Let's suppose the actual infected # in US today is 270K not 27K

And the actual infected # in India is 3300 and not 330

In which case, the multiple of Peak / Today is not 111 and 6000

But instead 11 and 600!

Which means cumulative Corona ICU demand of 11K and 9K

At any given point the ICU demand will be 0.3X11K and 0.3X 9k

That would be 3.3K and 2.7K

Now 3.3K is clearly way below the "slack" of 11K in US ICU capacity.

Very much manageable

2.7K is equal to India's hypothetical slack of 2.7K (which means we will be stretched a bit)

So Clearly this latter scenario is also concerning. But nowhere close to being apocalyptic unlike the first scenario

The purpose of this thread is to illustrate how important it is to get the denominator right as of today!

Depending on what the current infection rate is, you get a much better sense of how stretched you will be when the infection peaks in the next month or so.

This thread motivated by a discussion with @ritwik_priya

Post-script :

Now where does social distancing fit in this whole scheme of things -

Among all the assumptions in this thread, the one figure impacted by social distancing is 0.3 - the factor applied to cumulative ICU demand to get ICU demand at a given point in time

The more effective the social distancing measures, the lower that factor!

You basically flatten the curve, which means the active ICU demand at a point in time is a smaller proportion of cumulative Corona ICU demand