COVID-19 July 04, 2020

Data continues to show that are blowing past what we saw in the first wave.  And, yes, I do believe there was a first wave, contrary to what many are saying.  We are not still in the first wave.  There was a pronounced initial rise, a clear peak, and a gradual but persistent decrease.  That's a wave by most definitions.  It could be said that the first wave brought in the tide that didn't completely recede, but it is a wave nonetheless.  We've now seen a dramatic reversal of trends as the next wave comes in on top of the higher tide.  This is the second wave, and in terms of sheer numbers it is bigger.  Note that the data plotted in green on the new case graph shows the data since June 9 shifted and displayed over the first wave data.  The rate of rise is similar, but we've blown past the peak of the first wave.

Will the second wave be worse than the first?  Hard to say, but it seems likely.  Deaths still have not taken a rapid upward trajectory, but with hospitals and ICUs starting to reach capacity in the hardest hit areas it's hard to see how deaths will not start to increase.  The downward trend has certainly slowed and the 7-day trend has actually shown a slow increase rather than decrease.  See my previous posts over the last few days for additional thoughts about why this is.

Data is plotted below, as usual.  The best fit 7-day line shows just under 50,000 new cases/day.  The exponential fit to the new cases shows a doubling rate of close to 15 days.  This number has, fortunately, more or less stabilized and is no longer rapidly shrinking.  If and when we start to flatten the curve of this wave, we will need to see the doubling rate rise consistently. 

Have a good 4th!  My dog, Layla, thanks you for going easy on the boom booms.

EDIT: I reposted the daily new cases graph b/c I somehow managed to mess up some of the date labels in the original post. Data has not changed.

COVID-19 July 03, 2020

Independence Day or Groundhog Day? You decide!  I won't belabor the numbers from yesterday.  Unless you've been living in a cave, you all know the situation.

Today, I took data for the number of new cases since June 9 (shown in red on the daily new cases graph), shifted the values, and overlayed that data on the historical data from the beginning of the pandemic.  That shifted data is labeled as "June 9 shifted" in the graph and is shown in green. Surprise!!! The rise in cases since June 9 looks almost exactly like the rise at the start of the pandemic!

We really are right back where we started.  Or are we?  At the end of March, lockdowns were already well underway and the result was that the curve did start to flatten by early April.  For example, our office encouraged remote working on March 12 and less than a week later we shut the office down except for essential personnel.  That's not what's going on now.  Where we are now is roughly equivalent to where we were at the end of March, but rather than being in a process of increasing restrictions we are in an environment of loosening restrictions.  At least some of the state Governors got the memo and are requiring masks.  It seems unlikely that the curve is going to flatten anytime soon under these conditions.  I think we are in a far worse place:  Groundhog day on, I don't know, PCP?

I've had a few questions about why deaths are not rising in concert with the new cases.  I've addressed that here and there, but I'll drop my hypotheses in the form of an abbreviated list for clarity:

1)  Demographic shift in infections.  The morbidity probabilities are heavily skewed to the elderly. The initial pandemic hit the elderly populations hard, especially in nursing homes.  The current rise in infections is heavily skewed to the younger population who are less likely to die. (Note: that doesn't mean the young are immune.  Plenty of healthy, young people with no obvious risk factors are finding themselves dead or injured for life).  I expect this to start to change as young people bring their new viral friends home.

2)  Better treatments.  Through trial and error, treatments have improved at least a little.  This can't account for all the difference, but I'm going to guess it has some impact.

3)  Increased testing.  Part of the rise in infection rates is due to increased testing. If we had the same pathetic level of testing now that we had early on, the rate of increase would likely be different.  (Note: this has implications for whether we really are in a Groundhog Day scenario).  The increased testing cannot however explain all of the increase in new cases.  Not by a long shot.

4)  Virus evolution.  There is evidence that the virus has mutated, particularly in the spike protein that binds to the ACE-2 receptor of the human cell.  There is no evidence that this makes it any more or less lethal, but it does, apparently, make it more infectious.  There have been other mutations, but based on my limited understanding (and I want to emphasize LIMITED.  I AM NOT AN EXPERT and will defer to those that are if I say something that is inaccurate.  Experts: let me know!), there is no strong evidence that the virulence has been altered.

5) Other reasons.  There are almost certainly other influences that I've left off.

COVID-19 July 02, 2020

I barely have time to post, but I wanted to distribute today's graphs.  Text the word "UP" to 321321 for more information.

COVID-19 July 01, 2020

And July starts off with a BANG!  Things are back on the rise as they almost always do on a Tuesday.  Numbers should continue to go up the rest of the workweek.  It's really just a matter of how much.  By the end of the week, we'll have over three weeks of data on the recent rise in infections.  That's enough data that the curve fits should start to become more meaningful.  Right now, the exponential fit is still showing infection rates doubling about every 15 days.  The average is now over 41,000 per day.  So, if the exponential rate doesn't change, we'll be at over 80,000 per day by mid-July.  

The death rate still hasn't gone exponential, but it isn't dropping either.  With each day we diverge more and more from what could have and should have been.  Oh well.  Water on the bridge.  

COVID-19 June 30, 2020

We had a nice little down day yesterday, as expected.  The rest of the workweek should be up, up, up, at least if history repeats itself.

Even though the daily numbers went down yesterday, the 7-day average for daily deaths actually ticked up for the first time in a while.  Is this the start of the anticipated upward trend?  The total number of dead and the daily death rate certainly are showing the divergence from the Gompertz model.  Not unexpected at all, but it's interesting to watch as it develops.  The difference between the data and model tells what could have been if we had done things correctly whereas the actual data tells us how badly we f*cked up.

There was some discussion on my Facebook wall about why it's taken so long for the death rate to respond to the increase in cases.  There's a couple of reasonable hypotheses.  First, the current increase in infections primarily has hit the younger demographics that are less susceptible to complications and death.  The initial peak in deaths had a very strong contribution from the elderly, especially in care homes.  The younger people dominating the cases now are still infected and contagious and they will eventually transmit that virus to the general population.  They just need to take it over to grandma's home.  That process introduces an additional lag.

The second possibility is that the virus is mutating to a less lethal form.  Evolutionary pressure tends to favor viruses that don't quickly kill their host, and our actions over the last few months may be adding to that evolutionary pressure.  The most severe and lethal cases often end up in hospitals where transmission is effectively terminated.  That's the end of the line for whatever virus is the hospitalized person.  Those that are not severe enough to require hospitalization are still out in the wild and can continue to spread their particular strain.

I note that neither of the two hypotheses are mutually exclusive.  There could be an increased lag in transmission and viral mutation.  And, of course, there could be entirely different explanations.  All this is likely to get sorted sometime in the future, but it's extremely hard to tease out the cause in real time.

COVID-19 June 29, 2020

Today and possibly tomorrow should be the last of the down days this week.  It will be interesting to see how much the numbers fall, if any.  Yesterday's numbers came in lower than the day before.  This was expected.  The numbers that come in today and which I will report tomorrow should also be lower due to the well established weekly oscillation.  After that, we'll see how high things go.  The exponential fit to the data since June 9 suggests we will be at over 50,000 new cases per day, on average, by the end of the week.  We are currently at a little over 40,000 per day based on the last 7 days.

COVID-19 June 28, 2020

Another banner day!  For the virus.  Yesterday should have been a down day for new infections based on the historical weekly cycle, but instead, numbers held steady.  It seems likely we will see shocking numbers by midweek as the upward branch of the cycle kicks in.  The doubling time for new infections decreased to 14.5 days based on all data since June 9.  The exponential fit to that is very good (84% correlation coefficient) considering the oscillations that are superimposed on the data.  The best fit for the number of daily cases is now just under 38,000 per day. 

Masks on. Buckle up.