Monday, March 9, 2020

Guest Post: @pdxsag on the WuFlu

[The latest by @pdxsag on the WuFlu / coronavirus pandemic. See his earlier posts, "Have We Cracked the Coronavirus Conundrum?", "Theories", and "More".]

A concept from science and engineering is that a difference in degree greater than an order of magnitude, makes for a difference in kind. The most obvious example of this phenomenon is with travel speeds. Walking, driving, and flying are each an order of magnitude faster than the preceding, which makes for a difference in kind.

With regard to public health, WuFlu's communicability versus the seasonal flu makes for a difference in kind. Treating Covid19 like seasonal flu is skirting a public health disaster owing to the graphic below. If the infected population in need of treatment at any point in time ever exceeds the local healthcare system's capacity, people will die. The area under the curve is not important. What is critical is the height of the curve. A highly communicable, fast spreading virus obviously drives up the height of the curve, all other things equal.

In Wuhan, Iran, and Italy, Covid19 spread so fast that it overwhelmed the local health infrastructure in just a matter of days. In the aggregate it, indeed, appeared to be a “devil virus,” as Chairman Xi called it.

However, on the individual level, where we were looking at the severity, many innocuous case reports left us mystified. The quintessential example was the American evacuee from the Diamond Princess that fell ill on the flight back from Japan. He admitted on NPR interview he wasn’t sure if he was just jet-lagged.

It was a conundrum. No one knew what to think. Various theories, myself included, were floated in attempt to square the circle.

However, what if we ignore the infection rate and consider only the severity? What can be learned?

Locally, at the Life Care assisted care facility near Seattle, Washington, we have a reasonably good view at its severity (see). Though, as usual, you have to read between the lines, as well as backwards, forwards, and sometimes sideways.

Nine Life Care residents have died in the last two weeks. That’s as severe as it gets, and sounds very disturbing. On the other hand, they all were over 70. In the realm of geriatrics, 70 is not old. My church is full of 70 year olds that are still living at home and leading vigorous lives. Ironically enough, they were the majority in attendance this morning. To be in assisted living in one’s 70’s is the absolute bottom decile of health.

Instead, let’s consider those who haven’t died. The article clearly states all the residents have been exposed. If all the residents have been exposed, then certainly all of the staff have been exposed as well. We aren’t told how many residents live there or how many staff work there, but we are told 21 residents tested positive and another 12 people in the rest of King County are known to be positive. It seems reasonable to infer the other 12 are the staff and/or their close relatives. That’s 33 people that have been exposed to the virus for the last 2 weeks and are not showing severe, life-threatening symptoms.

We also know 34 police and firemen were exposed due to responding to calls at the facility. They are under quarantine at present, but only half are showing symptoms, and zero have required hospitalization. The severity of the symptoms isn’t stated, but we do know anything up to an including jet-lag qualifies as flu-like symptoms. That’s now 67 people that have been exposed in the last two weeks and are not showing severe, life-threatening symptoms. The bottom line is that this outbreak appears to be not severe. Zero people healthy enough for full-time employment have required hospitalization.

The problem we have is at the early stage of an outbreak, only those sick enough to show up at a hospital are tested. We suddenly see 50 sick people and jump to the conclusion there’s an incipient pandemic. However, it’s possible hundreds of people are already infected and the symptoms are so mild they recover at home or perhaps don’t even know they are infected. We don’t know if we are seeing the first 50 of 50 people with the infection, or the first 50 of 5000 people with the infection.

To really know the severity we have to test the entirety of the population. Interestingly enough we’ve had exhaustive testing in two places where WuFlu is endemic: the notorious Diamond Princess Cruise ship and South Korea.

The Diamond Princess had 3700 people aboard. There were 1000 crew, which is to say 1000 people healthy enough for full-time employment, and 1700 guests, which is to say 1700 people healthy enough to choose to go on an expensive vacation.

In the end, nearly all were tested. In the close confines of a cruise ship 20% became infected. The severity among those 700 infected was 7 deaths, or 1%. All were over 70 years old, 2 were in their 80’s.

Now let’s consider South Korea. They are testing nearly every person. There are 7,000 tested and confirmed cases. 50 people have died. It’s also reported that about 50% are classified as asymptomatic carriers. The health experts will call those 3,500 people super-spreaders. I call them 3,500 people healthy enough to not know they even caught the virus. I’m starting to think if my health is in the upper 50% of the population, I have zero worries over Covid19.

Finally, let’s look at Italy, since it’s the latest supercluster and coincided with commencement of the stock market sell-off. Italy has a significant elderly population. Italy is the oldest in western Europe. That is certainly going to cause the mortality rate to be overstated relative to what other westerns should expect. On Thursday, March 5, at a press conference with Vice-President Pence, median age of death in Italy was 82! On Saturday March 8, Italy quarantined the Lombardy region of 11 million people. This was done in response to 1500 new cases and 133 new deaths. More indicatively, 131, 98.5%, were over 60 years old and all had underlying health conditions. This is hardly something that warrants healthy people shelter-in-place and slowly burn through their stack of 2-ply.

Allow me to submit WuFlu is a stress test of public health after a lifetime on this map. It is a sit-rise test writ large.

The vast majority of people over 50 skate by on flu shots, herd immunity on account of their younger, healthier friends, family, and co-workers, and the fact seasonal flu is not grossly contagious. Most of them aren’t exposed to seasonal flu because it's not that prevalent in the environment.

What would happen if the seasonal flu were 10 times more contagious such that everyone in China or Japan or South Korea or northern Italy or the United States was exposed to seasonal flu within the same 3 week time period?

Given the poor state of general health, hospitals would be swamped and anyone over 50 with cardio-vascular disease or diabetes would be at serious risk of death. If you are not healthy enough to be certain you can catch and recover from seasonal flu at home, you are at high risk. While I think Covid19 is far less severe than seasonal flu, as a safely conservative approximation, if you would be reliant on the healthcare system to recover from seasonal flu, you must take extreme precautions. If the infection rate in your area tips into exceeding your locale’s hospital capacity you could well die.

Frankly, for the average American over 50, it doesn't look good. There are 110 million of them. Nearly half, about 45%, are obese, and 9% are severely obese (see). Their best and maybe only hope is that the low population density of the United States prevents WuFlu from becoming a true epidemic.

For healthcare workers it’s a different calculus. I suspect healthcare workers in Italy and China were severely overtaxing themselves in the midsts of crisis trying to hold back a failing dam and falling ill (see). At LifeCare, none of the employees have succumbed or apparently even been hospitalized. They were just as heavily exposed to the virus as the residents. From photos of the staff (see), they appear to be typical Americans, which is to say between obese and severely obese. For the millions of seriously unhealthy people, it is evident the healthcare systems cannot support surge demand created by a highly communicable flu.

I assume most CreditBubble readers are already high-agency types that have taken their health into their own hands with regard to a low carb diet, at least a modicum of strength training, and dietary supplements. The lowest hanging fruit for supplements would seem to be the Vitamin D Hammer (one-time dose of 50,000 IU) as well as zinc and NAC. Taking CoQ10 would be another idea, especially for someone taking a statin.

Good luck.


CP said...

Just to clarify, I do not think that this is a "bullish" post.

The good news seems to be that the virus does not have a 3-5% CFR, rather something less. The bad news is that it is worse than the flu and it is going to be hard on old, fat, and sick people.

Guess which country has a lot of old, fat, and sick people?

See LoTB's thinking below:

Most people, even most smart people, lack any ability to think independently for themselves. If they see no one else worrying about the virus, that means they don’t worry about the virus, and anyone who appears to be worrying is written off as paranoid, or they are making it up because they are out to get Trump.

Most people lack the ability to think in a non-linear manner. If they see 100 people infected with the virus this week, then they project 100 next week, 100 the week after that, and so on and so on, and conclude that the virus is no big deal. Sucks for 10 people each week who need hospitalization, but a minor health problem compared to even the flu. They don’t understand how epidemics spread in a nonlinear manner, that the number of infected doubles every so many days. If there is a doubling every 5 days, then it only takes 50 days to go from 5000 infected (no big deal) to 5 million infected (a pretty darn big deal) and then only 20 more days to go to 80 million infected. In the absence of action to contain the virus or increase social distancing, epidemiologists say that 40% will become infected before we develop herd immunity.

The number of cases, hospitalizations, deaths will continue to grow exponentially until quarantines are put in place. So far, government officials (at all levels, not just Trump) care more about asset prices than about the pandemic. They only care about the now, maybe partly because they can't visualize or comprehend two weeks ahead. See @toad_spotted tweet:

I'm dense, but I finally understand that all the discussion of "inspiring panic" has essentially zero to do with what people do in their ordinary days. If parents keep their kids home or stay home from work a day, it's hardly going to inspire chaos It's about stock market panics. Because stock panics can happen in an instant, the attention of politicians is almost entirely on managing day-to-day expectations and the impression of good news versus bad,rather than affecting the actual course of the epidemic by thinking through even one to two weeks from now.

The market is not discounting this yet, except maybe in cruise line stocks. Imagine how well cars - Teslas - are going to be selling for a quarter with rolling quarantines and crashing overvalued tech stocks. Can Tesla survive a quarter with de minimis sales? Because part of the business model is to be a stock promotion, Musk runs the company with a very fragile balance sheet.

Allan Folz said...

Interesting, though unconfirmed Press Release memo leaked on twitter.

Since 2/19:

120 residents
54 (50%) xfer's to hospital
26 (20%) deaths vs 5% typical
13 died at hospital positive for cv19
11 died on-site unknwn cv19 status
63 residents at present, 6 w/ symptoms

180 employees
70 (40%) with cv19 symptoms -- severity of symptoms wasn't shared

Allan Folz said...

Final Tally

from New England Journal of Medicine

The median age of covid patients was
83 years (range, 51 to 100) among facility residents,
62.5 years (range, 52 to 88) among visitors, and
43.5 years (range, 21 to 79) among facility personnel;

[Wow! 79 yo staffer? didn't kill her though...]

112 patients (67.1%) were women (Table 1).

The hospitalization rate was
54.5% for residents,
50.0% for visitors, and
6.0% for staff.

The case fatality rate (CFR) was
33.7% for residents,
6.2% for visitors, and
0.0% for staff.

94.1% of 101 facility residents had chronic underlying health conditions

hypertension (67.3%)
cardiac disease (60.4%)
renal disease (40.6%)
diabetes mellitus (31.7%)
pulmonary disease (31.7%)
obesity (30.7%) being most common.