Every week (since May this year), I look at the existing trend of a) growth in reported Covid deaths and b) growth in the positive cases for India. And then I run few scenarios to forecast when India will cross 1 lakh total reported Covid deaths. Total death toll as of yesterday (08 Aug 2020) stands at 42k+ (actual figure could easily be two times this value, for various reasons documented here).
On an average 858 people reportedly died per day this week (compared to 736 last week).
One could try forecasting the future cumulative deaths by simply using the existing growth rate trend for Covid deaths. There’s just one problem.
There is no existing growth rate trend for Covid deaths.
For example as you can see in the above chart, total weekly deaths this week (6000+) was a little over 15% higher than total weekly deaths the week prior to that (5100+). But the same thing last week was less than 5%!!
If one *must* project future Covid deaths just from the above chart, what growth-rate range would you consider? I would go by a range of anywhere from 5% to 15% week-on-week growth in total weekly deaths. If we do that, then below is how the projection for total cumulative deaths looks like.
So as per this simplistic projection, total death count will cross 1 lakh by anywhere between August-end to Sep-end (again, just to remind you, as of now the total Covid death toll for India stands at around 42k).
Alright, let’s now try a more nuanced (albeit indirect) approach to project cumulative deaths.
Let’s first look at the week-on-week growth rate of total weekly cases (instead of weekly deaths).
3.9 lakh total positive cases were detected this week, which is 9% higher than the total cases detected the week before (3.6 lakh).
Although for this week and the week before that, weekly total cases have grown by less than 20% week-on-week, in general this has hovered between 20 to 30% – as you can see in the chart above.
So based on the pattern so far, I expect the total weekly cases in the coming weeks to grow by anywhere between 20% to 30% (X). That’s my assumption #1.
Now in general, people who die of Covid in a given week, are either tested positive the same week, or the week before. Do we have some idea of what %age (Y) of such cases die? We do actually.
As you see above, death %age (Y) has been falling since its peak of 3.4% in the 07-13 June week.
6,000+ people died this week (02-08 Aug) which is 1.6% of half of total cases from this week + half of total cases from last week.
In other words, Y for this week is 1.6% (it was the same last week too).
Let’s assume that for the coming weeks, death %age (Y) could get as low as 1% and if something random happens, could say go up to a max of 2%. That’s my assumption #2.
Let’s forecast now…
Let me consider 3 scenarios (which are actually same as last week):
- X=20%, Y=1.5% (baseline)
- X=20%, Y=1% (optimistic: expecting even lesser %ge of deaths)
- X=30%, Y-2% (worse: expecting faster growth in cases AND even higher percentage of deaths)
With the above assumptions, below is how the future cumulative death count looks like:
The projection is pretty much the same as the first direct method I used. We will easily cross 50k before Independence day and then…
India will cross 1 lakh total deaths by end of Aug to latest by end of September.
Now, 1 lakh total deaths for India is basically equivalent to 72 deaths per million of the total population (in comparison, the present death toll of 42k+ is equivalent to ~31 deaths per million).
To what extent would the death toll figures keep going up?
If we look at other countries, death toll for many started to flatten out only after anywhere between 400 to 600 per million of their population died!! Scary, I know!
If we assume that for India, the death toll flattens out even at say 200 deaths per million, that would be equivalent to ~3 lakh total deaths!
It’s difficult to imagine why India would see any less deaths than that. The only populous countries across the globe where death toll flattened at much lower levels (like say Japan and China) happened when they somehow didn’t let the total deaths cross even 5k (Japan for example didn’t even let it cross 1k). We clearly couldn’t control things to that extent in India (most countries haven’t). So now let’s just be hopeful that the total death cap estimate that I am guessing is on the conservative end – otherwise, we could lose even upto 5 lakh people (or 362 deaths per million)!
That’s it for this post. I’ll get back with updated projections next Sunday (16 Aug). Stay safe.