Post #1170: Recent COVID case trend is unknown, Delta variant

I wish I knew what the recent U.S. trend in new COVID-19 cases was.  But the fact is that nobody knows.  Today’s data release, with data through 7/5/2021, had data from fewer than 20 states.  I don’t really think that’s enough for constructing a estimate of the current trend.

The fact is that between the states that no longer report on the weekends, the states that only report sporadically, and the July 5th holiday day, there’s really no current information.

In addition, we can probably expect the July 4th holiday to leave an artifact in the data similar to that seen for the Memorial Day holiday.  Some changes in testing behavior and speed of test processing, in addition to the plain fact that the states didn’t report information on new cases.

The upshot is that it may be well into next week before we get another clear fix on what the underlying trend is.


Delta variant incidence

I stumbled across a non-CDC source for information about the current incidence of the Delta variant.   This site is a Federally-funded project based at the Scripps Research Institute.  Based on their estimates, Delta currently accounts for about two-thirds of U.S. cases.

Source:  Outbreak.info  Julia L. Mullen, Ginger Tsueng, Alaa Abdel Latif, Manar Alkuzweny, Marco Cano, Emily Haag, Jerry Zhou, Mark Zeller, Emory Hufbauer, Nate Matteson, Kristian G. Andersen, Chunlei Wu, Andrew I. Su, Karthik Gangavarapu, Laura D. Hughes, and the Center for Viral Systems Biology outbreak.info. Available online: https://outbreak.info/ (2020)

The website has some technical problems, but the graph syncs up well with the older CDC data.  The CDC data showed that Delta accounted for 26% of cases, as of roughly June 14.  With a doubling time of about two weeks, that could easily result in the roughly 65% of cases shown currently, above.

To me, that’s something of a good news/bad news joke.  The bad news is, Delta is now the dominant COVID-19 variant in the U.S.  The good news is that outside of a few areas, such as southwestern Missouri, that’s not having a huge impact yet.  Case rates were starting to turn upward in a lot of places, but only modestly.

In any case, only 35 more percentage points to go, and it’ll be as bad as it can get.

Interestingly, the Delta-driven outbreak in Great Britain is continuing apace, and yet Britain is not postponing plans for removing their remaining COVID-19 restrictions.  Almost all new cases in Britain are the Delta variant.

The current rate of new cases in Great Britain is about 25,000 per day.  That would be equivalent to about 150,000 per day in the U.S., or more than ten times the current rate.

The mere presence of the Delta variant does not guarantee an outbreak.  Almost two weeks ago, Germany passed the point where half of new cases are the Delta variant, and they have seen no uptick so far:

I think the upshot of all of this is that we’ll get there when we get there.  Odds are still in favor of a major uptick in new cases, based on the increased infectiousness of Delta.  We were starting to see a broad upward movement in new case counts last week, but it didn’t appear to be centered on the states that the CDC said had the highest incidence of the Delta variant.

Maybe by the end of the week the picture will be clearer.  The US CDC is due to update its state-level estimates some time this week.  Presumably, most states will have reported current counts of new cases.  I’ll reassess at that time.

Post #1027: A correction on my William and Mary calculation

Same story as before, just a different baseline.  The upshot is that the red line — the expected count of new COVID-19 cases — should be based on 70% of total student enrollment.

And as a result of that correction, W&M’s COVID-19 incidence is not much different from what you would expect, based on the community rate.  But it’s not (yet) better than you would expect.  At the current rate, it’s going to take another week or two to get there.

Details follow. Continue reading Post #1027: A correction on my William and Mary calculation

Post #1024: I just got my first smart phone, and I’m beginning to understand what’s wrong with America.

Sometimes there is value in being an outsider.

I’ve just gotten my first smart phone.  I guess I’m only a decade and a half late to the party.

But as a result of my tardiness, I am now deeply weirded out by things that I assume all Americans now simply take for granted. Continue reading Post #1024: I just got my first smart phone, and I’m beginning to understand what’s wrong with America.

Post #1023: Next N95 mask purchase

Currently, I’m wearing the Kimberly-Clark N95 duckbill, on sale at Amazon for $52 for a bag of 50.  This was my choice for an N95 mask purchase, for several reasons:

  • Solid evidence that these are genuine (read the Amazon comments).
  • Reputable US manufacturer (Kimberly-Clark)
  • Reputable seller (Amazon), available from other reputable vendors.
  • Industrial mask not suitable for hospital use (NIOSH-certified but not FDA-certified)
  • Cheap, at $1/mask.

When you add all that up, what that mostly means is that there’s not a lot of profit in trying to counterfeit these.  Continue reading Post #1023: Next N95 mask purchase

Post #1020: PriUPS

This post is prompted by a recent article on Texans using their hybrid vehicles as electrical generators.  This being Texas, of course the vehicle in question is a pickup truck, in particular, the Ford F150 hybrid pickup.

And so, in 2021, Texan F150 hybrid owners are finding out what Prius owners have known since at least 2005:  A hybrid car makes an excellent backup generator.  In this post, I’ll lay out the simplest approach to using your Prius (or similar full hybrid) as an emergency generator. Continue reading Post #1020: PriUPS

Post #1013: Thirty percent of new Virginia COVID-19 cases are “probable” cases.

Source:  Calculated from Virginia Department of Health data, available at this URL.

Virginia’s COVID-19 case count includes both confirmed and probable cases.  And that’s a good thing, because the technology of testing has changed over the course of the pandemic.
Continue reading Post #1013: Thirty percent of new Virginia COVID-19 cases are “probable” cases.

Post #955: More people saying “get a better mask”.

This might be a case of finding what I’m looking for.   But I seem to be seeing more mentions in minstream media regarding the need to wear N95 masks (respirators).  In particular, I see more people pointing to citizen use of N95s as a rational response to the new, more contagious British variant of COVID-19.

In mid-2020, a policy of reserving N95s for health care workers made sense.  But now that domestic production has increased several-fold, and even a hard-hit state like Minnesota has a half-year supply on hand for hospital use (see below), and we’re facing a faster-spreading COVID variant, it’s more than time to rethink that, and start getting N95s into the hands of the public.

Continue reading Post #955: More people saying “get a better mask”.

Post #929: An odd footnote on the post-Thanksgiving surge that never happened

Source:  Plotted from data from the NY Times Github COVID data repository.  Data reported through 12/26/2020

Edit:  You can now see this clearly, with 20-20 hindsight, in (e.g.) Post #941.  The holidays do, in fact, put a significant dip in the reported infection count.

Holidays introduce several types of artifacts in the data on new COVID-19 cases.

There’s an immediate “reporting” artifact.  Many public health departments are short-staffed on the holiday, and they aren’t able to tabulate all the new COVID-19 test results that arrive on the holiday itself.  That creates a sharp one-day dip-and-rebound in reported rates.  We saw that at Thanksgiving, predicted in Post #901, confirmed just post-Thanksgiving in Post #909).  And, as above, we’ve now seen that same pattern for Christmas day.

There are other artifacts, but they will be more subtle than that, and harder to spot.  Presumably, there’s a slowdown in the actual rate of testing (because who goes out on Thanksgiving to get a COVID-19 test), and that shows up as a dip in the rates a few days later.  Finally, there’s the actual “surge” — if any — the actual increase in infections due to holiday travel and such, that shows up anywhere from 12 days to three weeks after-the-fact.

This post is about an odd discovery that I made when try to smooth out the Christmas reporting artifact, shown above.  The discovery is that there isn’t a simple offsetting dip-and-rebound in the reported rates.  The rebound isn’t as big as the dip.  There’s actually a small, permanent one-off reduction in the number of positive cases found, associated with that holiday day.  True for Christmas.  And, in hindsight, true for Thanksgiving as well.

It’s as if some people who would have tested positive just never bother to get tested.  Presumably, because of the holiday.  And never get tested afterwards, to make up for it.  Presumably because, eh, they probably don’t have a very bad case of COVID-19.  And so, apparently, just deal with their COVID infection.

This is no more than an odd footnote.  My real goal here was to talk about trends.  But, in fact, I just have to let the Christmas data glitches work their way through the system before I can talk about trends again.

A small amount of detail follows. Continue reading Post #929: An odd footnote on the post-Thanksgiving surge that never happened

Post #927: Wheelchair floor-to-chair aid, V3

The brief for this task:  Create a floor-to-chair aid for wheelchair users.  It must be able to be made at home, using only simple hand tools and readily available materials.

The end result is shown directly below.

Above:  Floor-to-chair aid, folded and covered.  For scale, the push-up bars sitting on top are 6″ tall.

Above:  Rear view, folded.  Lower stairs sit atop upper stairs when folded.  The boxes nearest the camera flip away from the camera when put into use.

Above:  Rear view, unfolded.  Lower stairs have been flipped off the top, away from camera, revealing hardboard stair tops.  Push-up bars are on top.

Above:  Front view, folded.  Blue cloth connects the lower and upper sections of the staircase.

Above:  Front view, unfolded.  Lower stairs have been flipped off the top, toward the camera, revealing hardboard stair tops.  The blue cloth keeps the upper and lower stairs connected. Continue reading Post #927: Wheelchair floor-to-chair aid, V3