Friday, April 10, 2020

Don’t look for “light at the end of the tunnel” here. I just see tunnel.



I’m going to start featuring each day with what I now consider the most important projections of all of the projections I’m doing: the projections of total deaths by week. As these grow, people will focus almost exclusively on deaths, not cases – as well they should, since the case numbers are probably far from reality, because of the huge deficiency in testing. All of these numbers are generated by growing yesterday’s total deaths number by the 3-day growth rate of that number. Here’s the good news: The three day death rate is down from 54% to 53%, so all of these numbers are down one or two percent from the ones I showed yesterday (and the date that we’ll pass the 9/11 toll in a single day is now next Monday, not Easter Sunday).

But what’s the bad news? There is no current downward trend in new deaths. For example, the 3-day growth rate was 48% four days ago. Of course, the rate is definitely down from April 1, when it was 105%. You might say “That’s great! If the rate falls in close to half every ten days, it will be about 30-35% on April 20! That will be real progress.”

To examine what the numbers would look like if that happened, I lowered the 53% 3-day growth rate in new deaths that I’m using now to project new deaths by 2% each day, so it ends up at 33% on April 10. As you can see immediately below this, that lowers total deaths on May 1 alone by about 5,000 to 57,000. Only 57,000 deaths in one day! Isn’t that cause for celebration? I really don’t think so. I’ve been saying since I started this blog that the most important thing to consider is coronavirus infections and deaths grow exponentially. If you knock down the growth rate but you don’t stop new infections cold, you’ll be back where you were in a month or two. Remember, at the beginning of March, there were only 100 cases and 6 deaths in the US. Look where we are now, just 40 days later.

So unfortunately, the idea of flattening the curve is no longer relevant – we’ve missed the chance to do that. Now there are so many totally unknown cases out there that we only learn about them when they die. If we had a good idea of the total number of cases in the US as well as who was infected, a drastic slowdown in the growth rate could itself be of some benefit – so we might, say, loosen the social distancing when the rate of increase in deaths was down to five percent.

But given that we don’t even know who’s infected now, we can’t even consider loosening up until we do – and also until we have almost ubiquitous testing. Who’s going to want to go back to work or school if they know the guy in the next cubicle or desk might be infectious and not know it? There’s going to have to be weekly testing at least for every worker – if not daily - except those who have had the disease and have the antibodies to prove it.

That means we need a national lockdown that’s as near total as possible, and the end to all travel of say more than five miles (more in rural areas, of course) except for food shopping, hospital visits, etc. And it has to last long enough that we’re fairly sure almost all cases have been identified. Then we can gradually start opening up, assuming there’s lots of testing available then. And if there’s not much more testing than there is now (and people don’t wait 1-2 weeks for results as they do now, meaning they’ll be infecting others that whole time), we’ll have to wait until there is. The fact that we’ve been so far behind on testing from the very beginning is why the US is in such a mess now, and why we’ll without doubt end up with not only the most deaths in the world, but perhaps the most per capita as well.


All numbers below are based on yesterday’s reported figures of total confirmed cases, total deaths and total recoveries, published on Worldometers.info. I’m happy to send my spreadsheet that calculates all of these to anyone who wants to check the calculations, although they follow the assumptions described below.

Date on which the number of new deaths on that day will probably exceed the toll of Sept. 11: April 13
Projected* number of actual deaths during week ending April 11 (Saturday): 14,240
Projected* number of actual deaths during week ending April 18 (Saturday): 36,985
Projected* number of actual deaths during week ending April 25 (Saturday): 104,325
Projected* number of actual deaths during week ending May 2 (Saturday): 277,918
Number of new deaths on May 1 alone: 57,474
* Projected deaths for each day = previous day’s deaths grown by yesterday’s 3-day percentage growth rate in new deaths – equal to 53%. The weekly number is the sum of the projected deaths for the 7-day period.

I. Numbers based on total cases, actual and projected
Total US confirmed cases: 468,895
Increase in cases since previous day: 33,735 (vs. 34,611 increase yesterday)
Percent increase in cases since yesterday: 8% (vs. 9% yesterday)
Percent increase in cases since 3 days previous: 28% (vs. 29% yesterday)

“Set in stone” US deaths* over course of pandemic:  189,154 (based on 4% case mortality rate)
*This number assumes a) Total cases grow by 28% into the future (= yesterday’s 3-day growth rate in cases); b) We impose a massive lockdown, with prohibition of all non-essential travel, today; c) New cases drop to zero in 28 days, because of the lockdown, but they continue to grow at the current projected rate up to the 28th day; d) testing is widely available by the 28-day mark; and e) case mortality rate = 4%. To consider a 6% mortality rate, multiply each projection by 1.5. For 8%, double it. For comparison, Italy’s case mortality rate is currently 11.75%.

Projected as of April 17 (7 days from today):
These numbers answer the question: What would happen if we wait seven days to totally lock down the US, based on the assumptions below (which frankly are themselves wildly optimistic).
Total expected cases*: 912,597 (vs. 859,854 expected yesterday)
Total expected deaths set in stone** over course of pandemic: 362,790 (vs. 369,646 expected yesterday)
* The expected cases number assumes that total cases grow by 28% for the next 7 days (= yesterday’s 3-day growth rate in cases).
** The expected deaths set in stone number assumes that a) Total cases grow by 28% into the future; b) We impose a massive lockdown, with prohibition of all non-essential travel, on April 16; c) New cases drop to zero 28 days later, because of the lockdown, but they continue to grow at the current projected rate up to the 28th day; d) Testing is widely available by the 28-day mark; and e) case mortality rate = 4%. To consider a 6% mortality rate, multiply each projection by 1.5. For 8%, double it. For comparison, Italy’s case mortality rate is currently

Projected as of April 24 (14 days from today):
These numbers answer the question: What would happen if we wait 14 days to totally lock down the US, based on the assumptions below (which frankly are themselves very optimistic)?
Total expected cases*: 1,611,111 (vs. 1,554,524 projected yesterday)
Total deaths set in stone* over course of pandemic: 649,928 (vs.  670,426 projected yesterday)
* The expected cases number assumes that total cases grow 28% for the next 7 days (= yesterday’s 3-day growth rate in cases).
** The expected deaths set in stone number assumes that a) Total cases grow by 28% into the future; b) We impose a massive lockdown, with prohibition of all non-essential travel, on April 23; c) New cases drop to zero 28 days later, because of the lockdown, but they continue to grow at the current projected rate up to the 28th day; d) Testing is widely available by the 28-day mark; and e) case mortality rate = 4%. To consider a 6% mortality rate, multiply each projection by 1.5. For 8%, double it.

Date on which 500,000 deaths will be set in stone: April 21  
Date on which 1 million total pandemic deaths will be set in stone: April 30
Number of deaths set in stone on April 30: 1,064,482  


II. Numbers based on total deaths, reported and projected
Total US deaths as of yesterday: 16,697
Increase in deaths since previous day: 1,900 (vs. 1,940 yesterday)
Percent increase in deaths since previous day: 13% (vs. 15% yesterday)
Yesterday’s 3-day rate of increase in total deaths: 53% (vs. 54% reported yesterday)

Date on which the number of new deaths on that day will probably exceed the toll of Sept. 11: April 13
Projected* number of actual deaths during week ending April 11 (Saturday): 14,140
Projected* number of actual deaths during week ending April 18 (Saturday): 36,985
Projected* number of actual deaths during week ending April 25 (Saturday): 104,325
Projected* number of actual deaths during week ending May 2 (Saturday): 277,918
* Projected deaths for each day = previous day’s deaths grown by yesterday’s 3-day percentage growth rate – equal to 53%. The weekly number is the sum of the projected deaths for the 7-day period.


III. Reported case mortality rate so far in the pandemic in the US:
These numbers are also unaffected by the error I made.
Total Recoveries in US as of yesterday: 25,928
Total Deaths as of yesterday: 16,697
Deaths so far as percentage of closed cases (=deaths + recoveries): 39% (vs. 39% yesterday) Let’s be clear. This means that, of all the coronavirus cases that have been closed so far in the US, 39% of them have resulted in death (compare that to the 4% mortality rate I’ve been using to calculate total pandemic deaths, based on total cases). Of course, this number will come down as time goes on and more cases are closed in which the victim recovered. But it’s only come down by about 4 percentage points since Worldometers started publishing the recovery rate on March 26, and on about half the days, it’s gone up; there is still no sign of a downward trend. I’d say it’s much more likely my 4% mortality rate will turn out to be too low, after the pandemic’s over and all of the bodies have been counted, than it will be too high.




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