Last report I talked about why the population ceiling for known active cases is so low. I’ve pinned that discussion to the bottom of this report in case you want to look at it again. In any event, it’s been a puzzle as to why more people don’t get COVID. It seems from the data that known active cases in any geographical area hit a hard ceiling of 0.25% to 0.50% of the population, then begin a downward path. I’ve come to the tentative conclusion that this is a result of a substantial percentage of the population with some resistance to the disease. I’m not a disease expert, but I’ve been seeing more academic research pointing in this direction. Here are two relevant articles:
https://www.cell.com/cell/pdf/S0092-8674(20)30610-3.pdf This one suggests that 40-60% of the unexposed population has some level of latent COVID resistance.
https://science.sciencemag.org/content/early/2020/08/04/science.abd3871.full This one suggests 20 to 50%.
Both articles suggest that COVID shares the same T-cell response with the common cold, although both caution that this is speculative at this point. However, this is where my belief stands until we find a better explanation of this diseases’ slow propagation. It was unusual that COVID broke from exponential growth as early as March. Here is a quote from my March 25th report:
“A day or two early to make any conclusions, but it’s clear break from the previous exponential curve. “
That was early on, when we had just over 50,000 cumulative reported cases. We all expected the propagation to follow an exponential path for much longer than that. However, this disease slowed much earlier than anyone forecast. I believe the cross-reactivity with other corona viruses is the only explanation currently on the table. Could this be wrong – sure. I’m completely willing to adopt a new theory when a better one comes along, or this one is proved or disposed of over time. I am happy to see research moving in this direction, so we’ll know in time.
As always, feel free to send me your questions about my assumptions, methodology, or modeling in general.
- Likely date of active case peak (Chalke modeling): July 23
- Likely date of peak deaths (IHME): April 16 (last revision on August 6)
- Total Test Results reported today: 731,700 (very high)
- Total Pending tests reported today: 3,903 (extremely low)
- National reported case Growth Rate today: 1.13% (very low)
Shane Chalke Interviews
Groom Ventures has agreed to host a website that will archive my daily reports, and supplement with other commentary. John Groom worked at one of my companies back in the day, and is an excellent writer. The website is: www.howmuchrisk.com For those of you that post my daily report on Facebook, let me suggest you link to this site, as the direct Facebook posts don’t seem to copy the graphs.
Here is the national picture. We’ve dropped over 84,000 known active cases in just 2 weeks. We’re now down 18% from this last peak. 14 out of the 15 states that I track are down today – haven’t seen that kind of sweep in a long time. Could we have another wave? I don’t know, but I’m betting not. We’re running out of population centers that haven’t hit the population ceiling yet.
Look at the daily new cases. We’re looking at a pattern of decline for over 3 weeks now. Even the usual intra-week spike didn’t happen this week.
All the news now is about the daily death count, so let’s take a look at that. Here are the daily national deaths:
I expect daily deaths to lag active case count by 2-3 weeks, and the latest IHME model agrees. They expect daily deaths to level out in a few days, and begin declining again in 2 ½ weeks.
To help make sense of the daily death count, I’m going to continue to report my new statistic – daily deaths per 1,000 known active cases. Here it is.
It is obvious that this wave of COVID is far less deadly in relation to active case count. This stat will rise a bit because of the lag between case count and deaths, so should move back below 2 deaths per thousand in the next few weeks. I’ll say it again – this is nothing like April.
On to the states.
As I mentioned last week, Arizona is starting to look a lot like NY or MA, with a hard bounce off the population ceiling and a rapid decline from the peak. This state is down an amazing 52% from the peak of less than four weeks ago. This is a remarkable recovery. I wish the news would report some of this. The purely negative coverage does no one any service.
SC is now 20 days past peak. SC Peaked at 0.26% of the population, so I suspect this peak will hold. SC is now down 32% from the peak. Note that South Carolina double counts cases, as they treat each positive test as a new case (per The COVID Tracking Project).
Here is Florida – another strong recovery story. 21 days past peak active cases. Interestingly, I noticed Miami flattening first, but Miami was declining more slowly than the rest of the state. Florida peaked high, at 0.38% of the population, so I think this peak will hold. Florida is now down 41% from the top.
California continues to look better and better. I think it’s safe to say that California peaked 12 days ago (at least for now). California’s peak was only at 0.18% of the population, so I don’t know what to think here. It could be that the lower population density results in a lower peak. Let’s hope so. As always, I need to report that California is one of the states that counts tests rather than people.
Georgia is looking more and more like it peaked. Georgia hit a high of 0.25% of the population, so this could be the ceiling – just below the average for states that have peaked. Note here again, the case numbers are exaggerated. Georgia counts each positive test as a case (according to The COVID Tracking Project).
Texas is down from their high, but looking pretty flat for the past week. IF Texas peaked, it was 14 days ago at 0.23% of the population. I don’t know if this will hold. Texas also reports positive tests as cases, so is doing some level of double counting.
NC is looking pretty good for three weeks now, but if this is the peak, it’s at a very low level (0.14%). NC will stay in Phase 2 for 5 more weeks. I don’t think the numbers justify that, but the governor wants Phase 2 to overlap the start of the school year, so I suspect there was a fair bit of teacher’s union pressure. If it were me, I would have delayed Phase 3 by one week to let the decline solidify. IHME is now projecting peak daily deaths in NC now around August 20th. It’s interesting how NC and VA now move together since mid-June.
Here is the daily death report for NC. We’re seeing a mild upward slope in daily deaths, but I think this will reverse in the next 2 weeks, as known active cases are steadily declining.
Washington could have peaked, but I’m skeptical, as the high water mark you see here is at just 0.087% of the population. It’s been 18 days, though, so this is hopeful.
Nothing to say about NY and NJ – the picture says it all.
The rise in Massachusetts over the past 8 days is a result of the discovery of new historical cases (https://www.wwlp.com/news/state-politics/reported-error-caused-spike-in-massachusetts-covid-19-numbers/). Massachusetts, to their credit, has been carefully working to place the new cases on the appropriate historical dates, but the aggregation sites pick them up as new cases, as I’m showing here. It doesn’t mean growth – just the opposite. This will work its way through the numbers over the next week or so.
…And here is Michigan. Looking beautiful until June 10th, then beginning a steady upward drift. Michigan peaked at a low percentage of population (0.089%), so may continue to grow if my theory is correct. It is just one of several states that peaked early and low, and doesn’t seem to be done with COVID yet. Nonetheless, we see a nice drop over the past 5 days.
PA’s decline is now 7 days old. Encouraging, but I believe PA has more growth to come, as the peak was very low (0.091% of the population).
And finally, here is Colorado. Colorado is one of the states that has had aberrations in their data. I still report it, but I’ve shied away from any conclusions in this state due to the data irregularities. Very small numbers here. Colorado peaked at a very small percentage, so could peak again as well.
So that’s it for today. I’ll report again on Sunday or Monday.
The numbers are still very small as a percentage of the population. Unless you’re in a high density area, your chances of contracting COVID are very small. However, even though the probability is very small, that doesn’t help if you’re the one catching it. Everyone please continue to be as cautious as you feel necessary.
–Shane Chalke, FSA