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Boris Johnson: UK Mutation may be more lethal, as well
#1
https://www.sfgate.com/news/article/Bori...890721.php

At a Friday news briefing at 10 Downing Street, Johnson and his advisers gave the first indication that the strain might also be more deadly.

England's chief scientific adviser, Patrick Vallance, offered an example. He said that among 1,000 men in England age 60 years or older, the original virus would kill 10. The new variant, he said, would kill 13 or 14. That would represent a 30 percent rise in mortality, though it is important to note that absolute risk of death remains low.
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#2
(01-22-2021, 04:39 PM)Snorlax94 Wrote: https://www.sfgate.com/news/article/Bori...890721.php

At a Friday news briefing at 10 Downing Street, Johnson and his advisers gave the first indication that the strain might also be more deadly.

England's chief scientific adviser, Patrick Vallance, offered an example. He said that among 1,000 men in England age 60 years or older, the original virus would kill 10. The new variant, he said, would kill 13 or 14. That would represent a 30 percent rise in mortality, though it is important to note that absolute risk of death remains low.
13 vs. 10 is a big deal. This multiplies the number of deaths by a lot when considering the increased infectiousness.

What remains unsaid is the rate of hospitalization/ICU care required. That can also be significant.

It appears that Denmark is sequencing every known case of COVID. Krause, director of  Denmark’s State Serum Institute voiced concern that even the hefty lockdowns that they manage in Denmark won't control the virus.  (Link below).  In the US we sequence 0.3% of the cases. I do not have the competence to state whether that is sufficient to track such a phenomenon, but I am not confident that we know what is going on here. The article made it seem like Krause was worried that expotential growth of the virus despite lockdown would overwhelm the country before enough vaccines are available. I think this is very bad news.

https://www.washingtonpost.com/world/europe/uk-variant-covid-denmark/2021/01/22/ddfaf420-5453-11eb-acc5-92d2819a1ccb_story.html
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#3
A fixed percentage increase in CFR (case fatality rate) or IFR (infection fatality rate) is important, but more important is R, at least under our current situation.

If one thinks that we will have a vaccine that can get to herd immunity by a particular date (Dh), then the number that will die is proportional to the number infected by that date. IFR*I(Dh).

The number infected is bound by the total population. If everyone will eventually get the disease, then, with either 0 or infinite medical resources, it doesn't matter how fast they get it. But, we are still under the impression that we can keep the total infected to be less than the total population. Further, we only have limited medical resources and IFR goes up when the number of currently infected is higher than our medical capacity.

IFR should be considered a function of current infections. IFR(0) is the fatality rate with full medical care. IFR(1billion) will be essentially IFR with no medical care. If CI(t) is current infections at time t, I(t) is total infections at time t (so I(Dh) = Integral over t of I(t) for now <= t <= Dh),
deaths = Integral over time t of IFR(CI(t)) for now <= t <= Dh.

R is a measure of how many new infections are caused by the current set of infections. If you take the current number of infections now, the number of infections one generation later is I(now + 1 generation) = R * I(now). For COVID-19, 1 generation is about 1 week (some say 5 or 6 days). If the number of infections are increasing, R is > 1. If they are decreasing, R<1. (R also depends on the number of susceptible individuals.)

An increase of say 10% in R will increase the number newly infected by 33% in 3 weeks, by 61% in 5 weeks, by 985% in 6 months. This impacts both I(Dh) and IFR(CI(t)) for t < Dh.

But, society (individually and by government) is reacting to the infection levels and mortality. The rate of spread ® is roughly controlled by shutting things down and by interventions such as mask wearing. So, if society perceives the disease as deadly, it responds by tolerating tighter controls, reducing R. Perception is a squishy concept. Things like public advice, news reports, and acceptance impact perception and the resultant behaviors. Perception is also impacted by the (sometimes false) belief that certain behaviors are more important than causing a few more people to be sick.

Society tried hard shutdowns early in the history of the disease: In China in January and in the US and elsewhere in March. COVID-19 has the unusual aspect of being infectious before symptoms which allowed it to escape those shutdowns.


Last night, in a televised basketball game, I watched a coach talk (without a mask) to her unmasked players from within 1 foot of their faces. She exposed them to any virus she might be shedding, and herself to any virus they might be shedding. She could have and, by state rules, was required to be wearing her mask. If she and/or her players get sick, she'll probably consider that to be bad luck, rather than stupidity and a lack of hygiene. I'd love to challenge her on that action today while it is uncertain whether people will get sick through her actions. In my opinion, I'd likely hear a reaction similar to someone who drove drunk last night, "Well, I didn't kill anyone," to which I'd add "Yet".
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#4
M_T that's a lot of words. I am not sure what your point is, except that the reproduction rate is a driver. However, the mortality rate is a multiplier (not good if it goes up).

Yes, the reproduction rate is critical. Yet, the mortality rate matters too. Let's say that 4,000 people die in the US per day today. If the rate per thousand goes from 10 to 15 (just to make math simple, but I concede its't 13-14), then it's 6,000 per day. That's a big deal.

My point was that not only is it more infectious, but it's also more deadly. So we have this infection rate that an official in Denmark thinks is so bad that lockdowns don't stop it and the increased mortality makes for an even worse disaster.

I admit that we are reeling from new information that is not vetted and likely to be revised, but the multiplicative effect of higher R and mortality is frightening.

Right now, I'd take the vaccine with a way lower bar for safety.

I'd also like to comment on your anecdote. So many people we considered "careful" end up saying things that show me they just don't get it. The latest anecdote is that my father in law went to TJ's to buy a case of two buck chuck before he got his first shot. "I can't stand not participating in the commercial environment." he said. I wanted to reply impolitely: "Really? You don't care about dying or killing others?" Our family currently does not trust anyone to be in a bubble with. With the potential of vaccine availability increasing rapidly due to production schedule and additional EUAs, we should all be hunkering down more than ever because there are bad signs (increased mortality and infection rate) and good signs (more doses). Being paranoid right now is the best time to do so.
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#5
Both of your posts are correct. I think in California we have seen the worst of it, variant or no. 30+% have had it, and the ones who have are more concentrated in high contact jobs. As long as society doesn't relax too much, too quickly, as our vaccination percentage increases, slowly at first but steadily getting quicker, we'll be able to get back to pretty normal by the summer.

It's hard to tease out worse mortality from a more virulent variant versus from an overloaded health system. The covid patient in October and the covid patient in December were receiving different levels of care, in the UK and CA. And particularly if the effect is only a few percentage points more lethal. I'm a bit skeptical, I'll wait for better data before worrying too much.
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#6
Help me understand what's wrong going to Trader Joe's. I've been going to TJ's, Whole Foods and Safeway throughout the pandemic. Target on occasion, too. Masked every time, though no longer wipe anything down when I come home, as fomite transmission turned out to be pretty much a myth. "Dying or killing others?" Seriously?
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#7
Is lethal defined as death/infected or death/population?

The former can hold steady even while the latter increases (as is the case if B.1.1.7 is more contagious, while keeping the same death/infected rate).

Of course, in the end, more people are dying, so either definition is no good.
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#8
(01-23-2021, 04:48 PM)cardcrimson Wrote: Help me understand what's wrong going to Trader Joe's. I've been going to TJ's, Whole Foods and Safeway throughout the pandemic. Target on occasion, too. Masked every time, though no longer wipe anything down when I come home, as fomite transmission turned out to be pretty much a myth. "Dying or killing others?" Seriously?

I think it's the chance that you will breathe in someone else's contagions.  And if the new variants are more contagious, it may take less concentration to get you.

But with all these questions, "wrong" is relative.
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#9
(01-23-2021, 04:48 PM)cardcrimson Wrote: Help me understand what's wrong going to Trader Joe's. I've been going to TJ's, Whole Foods and Safeway throughout the pandemic. Target on occasion, too. Masked every time, though no longer wipe anything down when I come home, as fomite transmission turned out to be pretty much a myth. "Dying or killing others?" Seriously?
Trader Joe's is awesome in every respect.

My in-law is 89 years old, has heart issues, is a cancer survivor, and is on a complicated pharmaceutical regimen. He also doesn't wear the mask over his nose, and his wife not at all. His wife also ticks off several comorbidities. We arrange to have anything he wants delivered. Yes, small gatherings of family is the #1 cause, but I wish this high risk individual could manage just four more weeks of not shopping especially because someone else does it for him. However, this is his choice and I must respect that.
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