All my various postings tracking the COVID-19 pandemic through the end of 2022.
Source: US Centers for Disease Control.
I first wrote about convalescent plasma in Post #616, 4/9/2020. The idea being, you take people who have recovered from COVID-19, filter the antibodies to COVID-19 out of the their blood, and give those antibodies to others, where they would help the recipients to recover from a COVID-19 infection. Continue reading Post #754: Convalescent plasma, updated
Above: Blue = Virginia, Orange = Fairfax County.
Below: Blue = NoVA+, Orange = rest-of-state
Well, this most recent uptick in cases is definitely not an artifact of data reporting. For two days running, the “early reopening” areas of Virginia have daily new cases well above recent trend. Daily new cases in the “late reopening” areas (NoVA, Richmond City, Accomack County) appear stable-to-falling there. But that is more than offset by the increase in the rest of the state.
(Weirdly, Vienna VA (22180) had seven new cases reported today. No clue what that’s about.)
And this continues to come from the Hampton Roads area.
In fact, the main reason today’s increase is smaller than yesterday is that the big jump in cases in rural Westmoreland County, VA did not repeat itself (See Post #752). Today they saw just 12 new cases. My guess is that they had an outbreak in (likely) a seafood processing plant, or some such. So far, I have found zero news coverage to explain the nearly 50 cases in two small towns (Kinsale, Hague) yesterday.
To put this into perspective, I can calculate an “annualized new infection rate”, meaning, what fraction of the population would get infected if the rate we just saw continued for a year.
The out-of-control states — Arizona, Florida — showed annualized infection rates (for the entire state) of more than 20%. So we can take 20% to be a true red flag for having a serious problem. By contrast, today, Fairfax County had an annualized new infection rate of about 1%.
Fully aware that these numbers will bounce around quite a bit from day to day, and that the lines with small counts will similarly show lots of random variation, here’s a snapshot of how Virginia looks today.
Based on the last couple of days, Portsmouth and Norfolk are about half-way to the Florida/Arizona level in terms of the current spread of infection. (The sort order of this chart is re-opening status and then descending count of new infections today).
By contrast, in the late-reopening areas, only the City of Manassas comes close to the 10% annualized new infection level. And that’s based on a small number of cases, within that small population.
So it appears that a true hotspot of trouble is developing within Virginia, in the Hampton Roads area. Per-capita new infections in two large cities are around half the level that has prompted such concern in FL and AZ. This is well worth keeping your eyes on, to see whether or not the Governor passes additional restrictions for those areas.
The conventional explanation for recent case growth — young people congregating in bars — doesn’t fully explain this. Yes for Norfolk, no for Portsmouth. In Norfolk, of the new cases over the past two days, 42% are persons age 20 to 29. But in Portsmouth, it’s just 21%, which is in line with the overall percent of cumulative cases to date. Whatever’s driving that growth, it’s not universally due to the behavior of young adults.
Virginia saw quite an uptick in COVID-19 cases today. Worst day in more than a month, as you would have to go back early June to find a day with more than 900 new cases reported.
The questions are, is this real, and what does this portend, if anything? Continue reading Post #752: Today’s uptick in cases
Edit: This did not work at all. Not even a little bit. See Post #790 for details.
In this post, I propose to rate masks on their ability to filter out cigarette smoke. The particles in cigarette smoke are roughly the same size as virus/aerosol particles. (Although their chemistry is quite different.) I am going to use those second-hand smoke particles as my best proxy for human aerosol emissions. The basic idea being that if a particle-filtering mask is good at removing something as small as cigarette smoke particles, it probably does a pretty good job at filtering aerosols in general.
I’m announcing the full scope of the test ahead of time because that’s good science. This way, I can’t just bury the results if they turn out unfavorable. (AKA, toss them in the circular file.) In some sense, it’s as important to know this doesn’t work, as it is to know that it does work, as a way to test masks.
The test is pretty straightforward: Light a cigarette, hold it under your face, and rate how strongly you can smell cigarette smoke while breathing through the mask. Less is better.
A cigarette is ideal for several reasons. One, it provides a consistent burn, meaning, a consistent concentration of smoke particles from one mask to the next. Two, it’s a readily-available and easily-repeatable standard. Three, the smoke has been well-characterized. Four, there is no risk (as with incense) that the material has been doused with molecules meant to volatilize as the base product is burned. If you smell tobacco smoke, you are smelling smoke particles. if you smell incense, it’s not clear what you are smelling.
I’m going to start with these five scenarios, hoping to establish some sort of scale:
The first problem is, I still have to manufacture items 2 and 3. I did a bunch of #3 masks for friends, early in on this pandemic. I need to make some more, document that, and then go on to make #2 masks. These should provide known filtration standards below N95.
Then I’ll rate the following six masks on that scale. These are the masks whose performance I am trying to judge. Starting with the beat-to-heck 3M dust mask that I have been wearing since the start of the pandemic, that I hope is still working well. And then some other alternatives that are readily available to the US public.
The point is to say whether or not you would materially improve your protection from aerosol-sized particles by swapping a plain-vanilla cloth mask for a typical generic, non-certified “KN95” mask offered as an impulse item at our local Ace Hardware. Continue reading Post #750: Science alert: Proposed cigarette smoke test of “KN95” and other masks
We’re now nine days into Phase III re-opening in Virginia. I doubt that most of you would have noticed that Phase III had started, if not for the fact that the Governor announced it. It certainly brought no sweeping new changes to my life.
We’re now at the point where any uptick in cases from Phase III re-opening should begin to appear in the data. (Typically, there’s 4 to 5 days between infection and symptom onset, and then another 4 to 6 for going to the doctor, getting tested, and having the test results reported.) If Phase III results in a wave of new cases, the earliest part of that wave should be appearing now.
So far, there’s nothing to report. The seven-day moving average of daily new cases in Virginia drifted above 600 per day. But that’s been rising for weeks now, due entirely to the “early-reopening” portion of the state. Fairfax County’s cases remain fairly low. And there’s not much else to say.
Here are my usual graphs, updated to today (7/9/2020). The underlying data source is case counts from the Virginia Department of Health.
Above, blue = Virginia, orange = Fairfax County.
Below: Blue = NoVA + Richmond + Accomack County, Orange = rest of state.
The cumulative case count for Vienna is back down to 229. The drop is probably due to cases that were thought to be COVID-19 based on symptoms and proximity to an infected individual, but turned out not to be, upon testing.
Sometimes its heartening to realize that the USA doesn’t have a monopoly on stupid. Sometimes, its disheartening. In this case, the latter.
Recall Post #745, regarding a letter sent to the WHO, signed by the 200+ of the Who’s Who of epidemiology, asking the WHO to reconsider its stance on whether or not airborne (aerosol) transmission of COVID-19 matters.
Just to be clear, a) you’d have to be an idiot to think otherwise, and b) from an economist’s perspective, you’d have to be doubly an idiot not to say it. Why? It’s an “asymmetric risk function”.
Asymmetric risk? If you say it, and you’re wrong, you needlessly cost people a few bucks a head, for the extra wear-and-tear on their face masks. By contrast, if you don’t say it, and you’re wrong, people die in large numbers.
To an economist, this is almost a no-brainer. Masks are cheap. Lives are not. If the evidence suggests airborne (aerosol) transmission, then you should deal with that. As in, recommend that people wear masks, even with social distancing.
But this is precisely what the WHO refuses to do.
Just read this news article, or this one, in response to that letter. Oh, yes, we must have well-designed randomized clinical trials before we would dare to draw any conclusions.
Translation: Give is a couple of years, and we might be willing to offer an opinion on this.
It’s tough to get more out-of-touch with reality than that. There is no better example of Emerson’s foolish consistency. To these folks, there is one and only one type of evidence that matters: randomized trials. They are simply too stupid to be able to weigh the rest of the evidence that does not fit their medical-background clinical-trial paradigm.
So, as much as it pains me to say it, I’m with the President on this one. De-fund the WHO. Maybe in the ensuing crisis, they’ll sweep out the dead wood, and put in some people who can actually think. At which point, they would get our full support.
In my prior posting on this, I cited reporting that said:
“They’ll die defending their view,” said one longstanding W.H.O. consultant, who did not wish to be identified ...
If this is the best they can offer, we’re better off just getting them out of the way. Until the point where we cannot rule out the possibility that key staff in the WHO are not totally clueless.
Source: Depositphotos.com
Update 2: This didn’t work, at all. Not even a little bit. See Post #790 for details. You can’t use the odor of cigarette smoke to test mask filtration.
Update: See postscript at bottom. The ability of genuine N95 masks to filter smoke particles is well known and well documented. In that light, my proposed “sniff test” for KN95 masks looks fairly promising. To the extent that a mask reduces the odor of cigarette smoke, then it is filtering out virus-sized particles.
In Post #740, I noted that my local convenience store had “KN95” masks for sale. I’ve heard a rumor that one of the local hardware stores is also selling such masks. (I plan to check that out soon.) And I exchanged emails with neighbor who is in the process of purchasing some KN95s, from a couple of different sources, for daily wear at work.
In theory, wearing a KN95 gives you the same protection as an N95 respirator. So, in theory, upgrading from a cloth mask or similar to a KN95 is a smart thing to do.
In practice, not so fast. I’ve started looking into the “KN95” mask market, and it is complete chaos. I guess that’s no surprise. That’s more-or-less of a piece with the entire Federal response to COVID-19. Continue reading Post #747: Can Kents clarify KN95 chaos? Updated
Daily new COVID-19 cases in Virginia and Fairfax County, updated to data reported 7/7/2020. Blue = Virginia, Orange = Fairfax County.
An odd thing happened with today’s count of diagnosed COVID-19 cases in Fairfax. It fell. We lost 14 cases from the cumulative diagnosed COVID-19 case count for Fairfax County. Presumably, that occurs when the test results for “probable” COVID-19 cases show that the persons didn’t actually have that disease. They are then removed from the case count.
These corrections have been occurring all along, they are just normally hidden beneath the overall high growth rate. We only see them show up, as a negative number, when the number of new cases is quite small. For example, we’ve seen the case count in Vienna (ZIP 22180) fall a few times. And we see that because, typically, we only add a case or two per day, if that, in Vienna.
So, we can infer that Fairfax County had few new cases reported today. We can’t say exactly how few, owing to the size of this correction.
(Alternatively, those cases might have been mis-classified as to location, and were simply moved to some other jurisdiction. That seems unlikely, as there was no jump in cases in (e.g.) Fairfax City or Falls Church.)
Near as I can tell, the adjustment is unrelated to the large number of cases age 10 to 19 that appeared in the Fairfax data in the past few days (Post #744). When I compare 7/7/2020 to 7/5/2020 data by age (Virginia did not post the 7/6/2020 file by age), most of the adjustment seems to have come from the elderly. But it is also worth noting that there was no continued high growth of cases among the 10-19 age group, suggesting that was some sort of one-off incident.
For Virginia as a whole, the seven-day moving average seems to be slowly rising toward 600 new cases per day, up from a low of about 500 maybe three weeks back.
But the overall Virginia number is composed of stable case counts in the “late reopening” areas, and slowly rising case counts elsewhere. Here’s that comparison, updated to 7/7/2020:
Source: Same as above. Blue is NoVA+Richmond City+Accomack County. Orange is the rest of the state.
As I noted in earlier posts, that largest driver of that case growth is young adults in the Hampton Roads area (Post #744).
Vienna (22180) added four cases last week, for a total of 232 so far in ZIP code 22180.
Source: Same as above.
Source: New York Times 7/5/2020.
The upshot of this post is, social distancing is NOT enough. It’s not enough, due to aerosol (airborne) spread of COVID-19. If you are indoors with people other than family, wear the best mask you can get, KN95 and N95 included.
Recall the difference between droplets (particles 5 microns and larger) and aerosols (particles under 5 microns). Droplets rapidly fall out of the air. Aerosols can float in the air for hours.
“Droplet transmission” of COVID-19 is the reason for the 6′ social distancing rule. It’s what the CDC keeps nattering about, that the main source of transmission of infection is individuals who cough or sneeze and emit a bunch of droplets containing the virus. Even though that cannot possibly explain the spread of COVID-19 for the past four months or so (Post #565),because nobody has been dumb enough to be out in public while visibly ill.
But, stay out of sneeze range (6′), said the CDC, and you’re safe. Social distancing will solve this problem. Because it’s being transmitted by droplets.
“Droplet transmission” is the reason the CDC originally said that you didn’t need to wear a mask in public. The story is that if the droplets only go 6′, and you’re maintaining your social distancing, then masks are unnecessary. You’re out of cough/sneeze range.
But aerosol spread is the reason that outdoors is far safer than indoors. In crowded indoors settings, aerosols build up, raising infection risk. Outdoors, space and air currents disperse aerosols to levels that will (typically) not cause infection. (Droplets, by contrast, don’t care if you are indoors our out — they’ll only go six feet either way.)
Aerosol spread is the reason that singing is so dangerous. (I have numerous posts on that topic, which you may search for if you wish.) Singing generates aerosols at the same rate as coughing. Suffice it to say that the latest twist in that saga is that California has banned singing in church services. This is long after Germany did that, and after most mainstream denominations did that.
I believe I first started talking about aerosol transmission four months ago, in Post #573, March 6, 2020. That’s when it became obvious to me that, despite what the CDC was saying, the preponderance of evidence indicated that aerosol transmission of disease was a real and material threat. That’s about when I shaved my beard and decided to wear a mask whenever I was in public.
And the evidence has only gotten clearer and stronger since that time. It was obvious at that time that aerosol transmission had to be an important factor. It’s far more obvious now. Obvious, even to a mere economist like me, with no medical or formal epidemiological training. The only explanation of the facts was aerosol transmission of COVID-19.
But the World Health Organization (WHO) and the US CDC absolutely cannot bring themselves to say that aerosol spread of COVID-19 is real and material. No matter what the evidence. No matter that many important infectious disease (tuberculosis, measles) are know for aerosol spread. Despite overwhelming evidence of superspreader events that could only have occurred via aerosol transmission of disease.
Thankfully, many US institutions acted (to some degree) as if aerosol spread were real, despite what the CDC says. (Or, really, what it will not say.) And certainly, every state that has favored outdoor over indoor settings is implicitly acknowledging the importance of aerosols. (Because, hey, if it’s all about droplets, they only travel 6′ whether you are indoors or out.) Even the CDC’s altered guidance implicitly assumes aerosol spread matters (See Post #602).
And the result is that the guidance we get is illogical and inconsistent. We are doing a lot of things — such as wearing masks in public while social distancing, such as favoring outdoor settings over indoor, such as banning singing at religious services — that tacitly acknowledge that aerosol transmission in the community setting is a real threat.
But the WHO and CDC won’t just flat-out come out and say it. So there are other things that we all ought to be doing, that we aren’t. These include wearing masks indoors even if you are properly social distancing. These including favoring quick and cheap upgrades of commercial ventilation systems to include more circulation, and to use filters with high MERV ratings or to use high-rated 3M Filtrete filters.
And there’s one more thing we should be doing. I think it’s the reason the CDC ignores aerosol transmission. Above all, aerosol transmission of COVID-19 means that we should be providing at-risk workers with proper aerosol-stopping masks. Chinese-made KN95s would be just fine for that. And those seem to be readily available. And thanks to another hide-bound Federal bureaucracy — the FDA — those are still frowned upon for use in hospital settings. So, you might as well feel free to buy one.
I don’t normally just pull something out of the newspaper, quote it, and be done. But I think this bit of reporting summarizes what I’ve been saying all along, about aerosol transmission of COVID-19, and about the established public health authorities’ absolutely unwillingness to recognize that.
Ready: From this NY Times article, emphasis mine:
But the infection prevention and control committee in particular, experts said, is bound by a rigid and overly medicalized view of scientific evidence, is slow and risk-averse in updating its guidance and allows a few conservative voices to shout down dissent. “They’ll die defending their view,” said one longstanding W.H.O. consultant, who did not wish to be identified because of her continuing work for the organization. Even its staunchest supporters said the committee should diversify its expertise and relax its criteria for proof, especially in a fast-moving outbreak.
That sums it up for me. Hidebound academic outlook, unwillingness to admit error, only talk to a experts with a narrow viewpoint, require impossible-to-meet standards of proof. That’s what has kept us in this weird never-land where we are taking some — but not all — of the precautions that aerosol transmission should require.
It’s now four months since some untrained blogger — me — was able to put two and two together. And the WHO and the CDC still can’t deal with it. When this is all over, I sure hope some heads roll over this. Barring that, maybe the CDC can finally come to grips with aerosol spread, and can start recommending that we do all the things that implies.
Source: Analysis of new COVID-19 case counts through 7/5/2020, from the Virginia Department of Health.
The last few days have seen a possible uptick in COVID-19 cases in Virginia, as well as cases in Fairfax County. The seven-day moving average for Virginia (blue) is no longer flat, but has a slight upward slope. The seven-day moving average for Fairfax is no longer declining.
You can’t fully discount the possibility that this is just random noise. But I decided to drill down into the numbers, to the extent possible with publicly-available data, to see if there was any hint as to why.
Arguably the most interesting finding here is that the recent uptick in Fairfax cases contains a disproportionate number of school age (age 10 to 19) individuals. Not clear why that would be, though it is possible that the end of the school year resulted in more socializing within this age group. Continue reading Post #744: Uptick in Virginia and Fairfax cases.
