Interesting that it seems to suggest there is an optimal amount of distancing/lockdown/etc. to lower the peak, but avoid a big "rebound". I don't see a lot of discussion about how to find that optimum amount.
It has occurred to me that the planet is essentially conducting a gigantic experiment in virus evolution, by creating a novel viral selection environment never seen before. For example, how does it impact a virus if the strains most likely to send the host to the hospital, actually spread more than the strains most likely to be asymptomatic, because even asymptomatic hosts are in isolation?
Unless there is a vaccine or cure coming soon (there isn't), then the end result must be herd immunity, no matter what the policy. It would seem that we should be considering how to select for the healthiest segment of the population to provide that herd immunity, rather than trying to isolate as much as possible in the vain hope that it will die out prior to that point. If that was every possible, it has long since spread way too far to expect that to be possible.
There might be cases (e.g. MERS) where you can stomp out a virus before it spreads enough to cause herd immunity, but we have long since passed that point. I don't think most people (including policy makers) are thinking about the endgame properly (as this paper does).
As far as I can tell, there is one big unknown that makes planning particularly difficult: What are the long-term health effects from being infected?
If it turns out that some significant percentage of the population is going to have a negative impact over the course of their lives from this, should we continue to hunker down until a vaccine or better treatments are found?
This is not an unknown. We have very good data on outcomes. The media has been diving ever-further into niche stories of bad outcomes in order to drive clicks, but the numbers of cases driving these narratives are vanishingly small.
For the vast majority (>98%) of those who are under 60 and otherwise healthy, this disease is on par with the flu.
Even amongst those who are more vulnerable, the rate of long-term sequelae is low. It’s the people who end up in the ICU who are experiencing the most long-term effects, and those people are a single-digit percentage of a single-digit percentage of those infected.
As rossdavidh correctly pointed out, if we don't get a vaccine soon (which we probably won't), then herd immunity is virtually the only way out anyway. Even if it turns out there are long term health problems, that doesn't really change that calculus. Very few people can completely isolate themselves indefinitely (remember, the virus doesn't just magically not spread in supermarkets), and if everyone did that, most of us would starve and the few who didn't starve would inherit a post-civilization ruin.
It does change the economic break even point a little bit. If intervention A reduces infection count 10% in the time to a vaccine, whether it's worth it depends upon whether it prevents 20,000 deaths, or 20,000 deaths and 40,000 long term illnesses.
The threshold to herd immunity depends upon contact rate. So interventions well short of "lockdown" may not completely prevent the spread of the virus but still reach equilibrium at a lower number of people infected.
You're right, the question of where the break even point is is quite complex. Aside from the numbers you posted, it also depends on the economic side effects of "intervention A": better to be one of the 40,000 with long-term illnesses in a functional society, than to avoid the long-term illnesses but live in a non-functional society because we destroyed the whole economy.
The economy is a human construct, subject to redefinition if needed. It’s not some inevitable product of the natural world.
Sacrificing lives unnecessarily to “save the economy” is perverse in that the economy is supposed to serve us, not the other way around.
I’m not saying we should stay in lockdown forever, but I’d rather our leaders think creatively with a default view of “let’s be cautious with a global pandemic that has so far shown great destructive powers when left unchecked”.
There's this boogeyman floating around that "the economy" consists of a bunch of billionaires drawing lines on charts, drinking champagne and laughing at the proles. If any of that is going on and is costing lives, by all means, put an end to it.
But when I talk about "the economy", I mean the process that puts food on plates and electricity in houses. Someone has to grow the food, someone has to transport it, someone has to store it, distribute it. Sure, we could round up the world's billionaires and force them to do that, but unfortunately there aren't enough of them to do it for everyone, so someone else will have to do it too. And someone will have to service the cars and trains those workers take to get to work, and someone will have to watch their kids, and someone will have to provide toys to the people watching their kids, etc. etc. etc. THAT'S what I mean by "the economy".
You are completely ignoring the knock-on effects of this experiment, like driving an enormous population into destitution and fostering crime and violence.
Fewer than 300,000 people have died with nexus to Covid. Even if that population were to double, we're left with 0.0066% chance of death. It's great to be legitimately concerned, but those are good odds as far as I'm concerned.
WWII, the country came together, dealt with rationing for years. The draft and rationing forced everyone to sacrifice.
This disease has the potential to kill 3 million Americans, 70 million people globally, and that’s only if we spread it out.
Why aren’t we all sacrificing so that the poorest, most vulnerable population can have sufficient funding so that they will have a roof and food and clothing? Why isn’t the federal government sending monthly checks? Where’s my tax increase? Where’s why aren’t I being drafted to work in health care or food delivery?
All our government has asked of us, begrudgingly, is to stay inside for a while, and we can’t even do that without whining.
> This disease has the potential to kill 3 million Americans
This is looking less and less likely. With increasing evidence that the infection fatality rate is 0.6%, and that the herd immunity threshold may be somewhere around 30% infected, it's more like 700k. Still catastrophe, but 1/4th the catastrophe you imply...
> All our government has asked of us, begrudgingly, is to stay inside for a while, and we can’t even do that without whining.
I favored sheltering before everyone else. It was a good way to blunt the incident wave of the epidemic and prevent health care overload.
At this point, Rt with the current intervention isn't low enough to ever get us to a regime of extreme containment in any reasonable/attainable amount of time, and there's too many jurisdictions that are hotbeds of the virus that will just reintroduce it. I am not convinced that the current strategy saves lives in the long term.
It even risks backing us into a corner, where we have no choice but to reopen more than we'd like, and then face a devastating fall season with little population immunity and no seasonal factors on our side. Especially in locations like the SF Bay Area, under the nation's strictest health order but also with a very low per capita case load.
Worse, it's hard to be sure the intervention is even effective. Looking at data series on https://rt.live , there's no obvious inflection or discontinuity relating to sheltering or relaxing of sheltering in the individual states' series. Rt was falling before sheltering, and continued to fall at a comparable rate afterwards...
Uh, reducing transmission does prevent drastic overshoot past the herd immunity threshold, so it does affect the area under the curve a bit-- not just flatten it.
> Many people think COVID-19 kills 1% of patients, and the rest get away with some flulike symptoms. But the story gets more complicated. Many people will be left with chronic kidney and heart problems. Even their neural system is disrupted. There will be hundreds of thousands of people worldwide, possibly more, who will need treatments such as renal dialysis for the rest of their lives. The more we learn about the coronavirus, the more questions arise. We are learning while we are sailing. That’s why I get so annoyed by the many commentators on the sidelines who, without much insight, criticize the scientists and policymakers trying hard to get the epidemic under control. That’s very unfair.
Yeah, I read that anecdote, too. Saying “many people” is meaningless. A tenth of a percent of a million people is a thousand people. That’s “many people”, but the rate is quite low.
Facts: in the US, the hospitalization rate for covid is around 4.6 per 100,000. It’s half that for people under age 50. The rate of serious disease is very, very low...and this includes high-risk groups:
I can't understand the amount of intrigue surrounding this. It's not some kind of mysterious alien pathogen; there are 6 other coronaviruses that infect humans, and hundreds that infect other animals. There have been numerous outbreaks in the past 20 years. They're very well researched. Still, I'm not holding my breath for a vaccine since these other diseases, like SARS and MERS, are several orders of magnitude more letha.
> some significant percentage of the population is going to have a negative impact
Is there any evidence at all that this is some kind of feature of this disease? It's even starting to look like most people who become infected never even develop the associated disease.
This causes a whole lot more people to be hospitalized with severe illness. Severe illness tends to result in morbidity even if you survive.
A fair number of people with SARS-CoV-1 ended up with chronic fatigue ailments, etc, afterwards, too.
We don't know, but there's almost certainly going to be more lasting morbidity from this epidemic than the common cold. If it's a little bit, it doesn't change the calculation much. If 1/4th of those hospitalized develop significant morbidity though, that sucks.
From what I'm reading, the best case for a vaccine is 3 years (both development and production on a large enough scale). By which point, it's a moot point because the vaccine will have gotten to herd immunity levels long before that.
In other words, hunkering down won't really change the fact that the vaccine, if it comes at all, won't come in time.
Currently we need to learn more about this virus to make informed decisions - there is more we still don't know, than we do know for sure. Trying to slowly contain the virus like in South Korea, Taiwan, New Zealand is a strategy worth a shot for most of the western world, unless we learn something dramatic new about it. There is no need for draconian lock downs after exponential spread is stopped, but we do need good track and trace programs, masks etc. There are very high risks associated with Swedish strategy of either killing a lot of people due to bad separation of vulnerable people, destroying health of the big part of the population (see below), or even just failing to reach herd immunity because social distancing, closure of schools, and ban on mass gathering will be good enough to slow down the spread a lot, but bad enough to kill disproportionate amount of people. For example Sweden has many times more deaths than other Nordic Countries, but similar economical outlooks, and the even the idea of reaching herd immunity is uncertain. It may be that other Nordic countries will have soon less or about the same amount of restrictions as Sweden, but many times less deaths.
And regarding the risks, one of the scientists who discovered Ebola [0]:
"Many people think COVID-19 kills 1% of patients, and the rest get away with some flulike symptoms. But the story gets more complicated. Many people will be left with chronic kidney and heart problems. Even their neural system is disrupted. There will be hundreds of thousands of people worldwide, possibly more, who will need treatments such as renal dialysis for the rest of their lives. The more we learn about the coronavirus, the more questions arise. We are learning while we are sailing. That’s why I get so annoyed by the many commentators on the sidelines who, without much insight, criticize the scientists and policymakers trying hard to get the epidemic under control. That’s very unfair."
Also based on Japanese study on around 100 COVID-19 cases from Grand Princess passengers [1] and some 6 divers all with mild cases from Germany [2] around 50 to 80% of people seem to have damage to the lungs visible on CT scans after mild symptomatic or even asymptomatic infection. Two of the divers had significant oxygen deficiency when doing physical exercise after 5-6 weeks of recovery. The guess of the doctor who was inspecting them is that this is permanent damage that may take years to recover if ever.
I am worried about this disease. I am perhaps even more worried that I can't calibrate how worried I am supposed to be.
Case in point 'There will be hundreds of thousands of people worldwide, possibly more.' Taking 'hundreds of thousands' to be 500,000 and 'number of people worldwide' to be 8,000,000,000, we get 0.006% people with long term adverse side effects. This is much less than 1% we assume are going to outright die. Is this ballpark even remotely accurate? Do we have reliable clinical / epidemiological data to ballpark this number? Do models have any credibility left after being adapted on-the-fly by an order of magnitude or more?
As of the Grand Princess / 6 divers scenarios, something doesn't add up. Either 50% of people [in context, 4 billion] are going to end up with serious long term oxygen deficiency or not. If this is indeed the case, I don't understand why the medical community doesn't explain in more stern terms the severe [Black Death lite] long term implications. Given the implied severity, why don't we have a Manhattan project to replicate these studies, in every single developed country out there? Drop everything else you are doing, pick a 10,000 sized city with a sizeable outbreak and CT everyone in that city, repeatedly. Send the Army if you have to.
I'm part of a community whose whole purpose is to accurately predict future and calibrate based on established track record. Based on what you are saying, you may be interested in that. We normally focus on hacker news type of stuff, but recently we focused a lot on this pandemic due to the impact [0]. As an example of our track record - already in 2017 our best predictors were estimating 36% chance of this type of pandemic by 2026, my personal prediction was also 30%. You should look on our dashboard were we collected a lot of our community predictions here: https://pandemic.metaculus.com/COVID-19/ You can also compare our short term record vs. survey of experts here: https://works.bepress.com/mcandrew/8/
Our current best prediction is that 596 million people will get infected (247M-1.4B 50% CI) before the end of the year and that only 16 million (8.0M-36M 50% CI) will be reported to WHO. We expect also 1.74 million deaths (532k-6.0M 50% CI) world wide before the end of 2020. Overall infection fatality rate is likely to be 0.8% (0.5-1.2 50% CI).
And, I agree with you - we should have had massive projects for track and tracing already in February, but politicians almost everywhere dropped a ball on this besides Taiwan, South Korea maybe Germany and some other countries. In many places there are still no good exit plans.
Also, scientific community is slow to do anything. Masks are good example of that - making a masks at home costs nothing, so if widespread use of homemade masks have a chance to save lives and reduce length of lock downs even by days then the risk-cost-benefit analysis is just overwhelming in favor of widespread mask use. But medical community wants controlled trials and tip-top evidence before trying anything even if it's as simple as a mask.
Overall there seems to be a sort of fog of war going on.
From my perspective the models never had any credibility due to the fact that small errors in model parameters lead to exponentially big errors in predictions. Also, soon after China managed to contain the outbreak it became more or less obvious that human behavior is the biggest unknown in all epidemiological models. No model is able to predict how politicians and society will react.
Here is my comment from 3rd of March [2]:
> I think very important part of a model that intends to give real world prediction would be ability to model what happened in China. There needs to be something in the model that allows to slowdown the growth of infection.
Thankfully, big political decisions were never only based on models. They were based on 1. empirical data from SARS outbreaks in China, later on based on China and Italy experiences 2. simple common sense computations like around 20-80% of population can get it if we do nothing (Swine Flu or Spanish Flu) and 0.5-2% of infected can die based on Grand Princess and Chinese data. So the best case scenario assuming no reaction and wide spread like with Swine Flu or Spanish Flu is 0.1% of population dieing and the worst case scenario is 1.6% population dieing. It was obvious that reaction was needed given the severity of the best case scenario with no reaction.
I think what got missed is the fact the people across the world were already starting to react by themselves in early March soon after Lombardy went into lock down. You can see that in Google/Apple Mobility data and in Open Table restaurant reservations. People miss that piece of data even now as lock downs are lifted.
Regarding 50% - this is what shows up on CT scans. The paper does not provide much of interpretation of that scans. But seems like we can indeed expect reduced lung capacity at least soon after recovery in some nontrivial percent of the population. That much we know, the long terms effects are just a guess. I will probably try to make a quest...
Thanks for the thoughtful response. Wrt CT scans, the frustration is that we don't know the kind of selection biases led to the respective numbers. It's a couple of studies over non-random populations. 100 cases out of 3,711 passengers; 6 divers out of ??? divers out of 80M people in Germany. We got a couple numbers, how do we responsibly translate them into population-level risk assessments?
It seems like their simulated model makes certain members of a population less ‘active’ and so at less parametric risk of infection/transmission than in a model where everyone is active. This is useful, and/but doesn’t appear to be Covid-19 specific.
It isn't, and the same phenomenon has been observed in other cases. The 2009 swine flu for example had R0 estimated between 1.4-1.6, yielding a theoretical herd immunity threshold of 29%-33%, but estimates of how many people were actually infected range from 11%-21%.
I thought their point was that highly active people will have been infected in greater numbers after a lockdown, numbers that are even more divergent than without a lockdown, and thus less other people will need to get infected.
> The classical herd immunity level hC is defined as hC=1−1/R0
How do you use this in places where transmission is less than 1? New Zealand now has a transmission rate considerably under 1, but this seems to break the calculation.
Does this mean that a reproduction number under 1 doesn’t need herd immunity? We do, because we can’t stay locked down indefinitely, and presumably our rate will go up when we relax restrictions.
In this kind of modeling, outbreaks are considered to be impossible once transmission is driven below 1. (The herd immunity level is just the level at which the transmission rate is driven below 1 without additional interventions.)
The paper says that herd immunity can be achived easier when the disease itself does the spreading. Because in "classical" herd immunity the vaccination does not target the active population so well. Instead when the active population gets the virus naturally it will produce stronger herd immunity.
Okay I removed that part, but Tegnell has now and then suggested the Swedish model is "herd immunity" and then sometimes suggested it's not.
It does indicate the Swedish model could work, because the paper says it's just 43% with "disease-induced" herd immunity. And according to Swedish authorities 25% of Stockholm population already has antibodies.
As I understand the Swedes, Herd immunity is not the goal they are working towards, but a possible bi-product of their strategy. The strategy as such is to keep the curve low enough, pretty much the same as everywhere else. They've just used less extreme measures to achieve this because they don't think it will matter in the long run.
That is, if you want to give them credit for any strategy at all. And no, the curve is not the same as everywhere [0].
Being a resident Swede, my lasting impression is that the so-called "strategy" has two legs (can be backed by a long list of official statements) 1: hope that the virus does not hit, and if it does, that it is not necessary to do anything and/or it is already too late anyway and that hopefully it will disappear through herd immunity. A hope that has been expressed up to twice weekly for the last 2 months or so, while the number of deaths go up and up. And 2: in a manner typical of governmental agencies everywhere: never ever admit to any mistake or error in judgement. Like admitting that the recommendation for the public not to use face masks was wrong, and was brought on by secondary concerns (over availability in hospitals). Even now (as of yesterday) the official stance is that using face masks might increase risks and efficacy is not backed by "scientific proof".
The paper should probably be seen in this light. The main author of the paper Tom Britton forms together with Giesecke and Tegnell the "herd immunity" triumvirate that is responsible for the Swedish mess that currently renders Sweden a place among the top 10 countries with most fatalities per million. At the face of it this paper just seems to confirm that protective measures actually work. But by shining the light the herd immunity aspect of the equation he makes it sound like they were right all along.
I don't disagree with you per se. I think it's debatable how they differ. If you just search Tegnell and Herd immunity you will find that many news sources has interpreted the Swedish model as herd immunity.
Herd immunity is horrible word, and none wants to use it anymore. But because flattening the curve does leave the virus linging around, it in many practies is same as "flatten the curve" as pointed by epidemologists:
> The "Flatten The Curve" plan was touted by every public health organization, while the United Kingdom's original "herd immunity" plan was universally booed. They were the same plan. The UK just communicated theirs poorly.
All this talk of herd immunity is not terribly helpful because we don’t know what “immunity” means in practical terms.
The duration of immunity for other corinaviruses varies quite a bit, the disease has the potential to cause permanent respiratory damage, with uncertain consequences for the possibility of reinfection, and we’re still seeing novel symptoms arise as in the case of the children with Kawasaki-like inflammation in NYC.
I get the strong desire to return to a normal state of affairs, but paving over reality with scientific notions, deployed pseudoscientifically, does very little to get us there.
We know that the vast majority of people will recover fully, and after they recover they'll be immune for a long time. Media reports have severely overstated the uncertainty here; if coronavirus can indeed trigger Kawasaki syndrome, it's only in the same sense that acetaminophen can cause liver damage.
A combination of animal studies, observation of recovered patients, and some studies directly on the antibodies recovered patients produce. In the US at least, public health authorities have consistently said from the start that there's substantial long-lasting immunity.
This is not in anyway true and I’m not sure why you’re suggesting it is. Dr. Deborah Birx has said expressly that we don’t know the duration of immunity and initial reviews suggest immunity might not last as long as we’d hoped:
This article is discussing the hope that immunity lasts forever, and I agree there's no reason to believe that. The important question is whether it's shorter than a year or two - we're developing other strategies to handle the virus on timescales beyond that.
> This article is discussing the hope that immunity lasts forever
Nowhere is this stated or suggested. Why are you saying that it is? The only point it makes (contrary to all your claims) is we don’t know the duration of immunity and the situation is unpredictable, based on what we know of other coronaviruses. From the article:
>What I have been telling everyone—and no one believes me, but it’s true—is we get coronaviruses every winter even though we’re seroconverted,” says Matthew Frieman, who studies the virus family at the University of Maryland. That is, even though most people have previously developed antibodies to them, they get the viruses again. “We really don’t understand whether it is a change in the virus over time or antibodies that don’t protect from infection,” he says.
> After testing different scenarios, the Harvard group concluded that their projections of how many people end up getting covid-19 in the coming years depended “most crucially” on “the extent of population immunity, whether immunity wanes, and at what rate.” In other words, the critical factor in projecting the path of the outbreak is also a total unknown.
I've seen very different information on how long "for a long time" is. Even just writing "for a long time" makes me wonder, if you have a range, why not give it?
The figure for immunity duration at say 95th percentile seems to be the key figure for herd immunity being viable or not, at least to my layman eyes.
It's hard to put a concrete number on how long immunity lasts, because immunity isn't a binary process. All the experts I've seen discuss the issue have said we can expect recovered people won't catch it again this calendar year.
That's just speculation because no one has had the virus for a year.
Please stop adding certainty where it is unwarranted. Either supply citations to expert authorities, or be quiet. Otherwise you're just spreading misinformation.
Wouldn't this kind of reasoning apply to every new virus, including new flu viruses that pop up routinely? A new virus pops up and appears to be just a routine flu, but technically we can't know about its long term side effects until many years later. So why don't we apply this same reasoning and lock everything down routinely whenever any new flu virus arises?
It seems to me that you're right, we can't know for certain until many years later, but in the meantime the world goes on, we can't all just cryogenically freeze ourselves. The best we can do is make educated guesses based on previously existing coronaviruses.
I don't think they do have a range. I saw a slide a month or so ago that showed how long antibodies last for various viruses, and the range was something like 3 months to life. We simply have no idea how long SARS-CoV-2 antibodies will last.
Respectfully, these are just your suppositions, unless you have some evidence to the contrary. In every case I cited, there is no scientific consensus about what’s actually happening.
I’m not sure why people can’t seem to fathom that we are still very early in our understanding and experience of this disease, no matter how dramatic its consequences thus far. There’s no way to accelerate things through false confidence or other forms of denialism.
As I've discussed elsewhere, there is indeed evidence to the contrary.
There's also no way to decelerate things through false humility. We're in an urgent crisis, so we must make decisions now based on whatever evidence is available; there's no position of safety we can retreat to while waiting to learn more.
So provide a sliver of this evidence. You keep alluding to it, but your story doesn’t correspond to the CDC’s own statements, nor the initial review of coronavirus immunity durations I linked.
What kind of evidence are you looking for? I can point you to public health authorities saying immunity works and lasts for ~a year [1][2], but I suspect you've seen these statements already. If you're looking for a scientific study unambiguously proving it, we of course won't be able to have that until a year has passed.
Disappointing to see comments like this (and many others on this site) downvoted. There is nothing wrong with this comment, it's not offensive or shrill. If someone has an issue with the logic they should reply to it.
You're right, but it's getting downvoted because it has the same basic shape as the "people aren't creating antibodies and can get reinfected" doomer meme which is making the rounds.
Also, FWIW, if getting the actual disease doesn't generate sufficient antibodies to confer immunity, being dosed with a vaccine wouldn't either. Whether vaccine-supported or not, herd immunity is the most likely outcome (unless the disease becomes endemic instead). What remains to be seen is how many people have to get ill to get there.
My question is what R0 looks like in a city with mass transit vs without. The subway in NYC is huge and puts so many people together in close contact every day.
Is it outrageous to think R0 could be 3.5 in NYC but 1.5 somewhere else?
I think that, in the terminology of the paper, a higher proportion of New Yorkers would be considered 'high-active' compared to, say, LA, and perhaps there is a level that you don't even see in less crowded-mobile societies. I would guess it is helpful to keep the biological and social factors separate when modeling what is going on.
This is also true under much weaker assumptions. Here's a simple example calculation. Say 50% of a population has R0=1.5, 50% has R0=2.5; the average R0 is 2. Then the required herd immunity is (2-1/1.5-1/2.5)/2=0.47, below the classical 1-1/2=0.5. That this always true for any number of independent subpopulations is a consequence of the harmonic-arithmetic mean inequality.
72 comments
[ 5.9 ms ] story [ 116 ms ] threadIt has occurred to me that the planet is essentially conducting a gigantic experiment in virus evolution, by creating a novel viral selection environment never seen before. For example, how does it impact a virus if the strains most likely to send the host to the hospital, actually spread more than the strains most likely to be asymptomatic, because even asymptomatic hosts are in isolation?
Unless there is a vaccine or cure coming soon (there isn't), then the end result must be herd immunity, no matter what the policy. It would seem that we should be considering how to select for the healthiest segment of the population to provide that herd immunity, rather than trying to isolate as much as possible in the vain hope that it will die out prior to that point. If that was every possible, it has long since spread way too far to expect that to be possible.
There might be cases (e.g. MERS) where you can stomp out a virus before it spreads enough to cause herd immunity, but we have long since passed that point. I don't think most people (including policy makers) are thinking about the endgame properly (as this paper does).
If it turns out that some significant percentage of the population is going to have a negative impact over the course of their lives from this, should we continue to hunker down until a vaccine or better treatments are found?
For the vast majority (>98%) of those who are under 60 and otherwise healthy, this disease is on par with the flu.
Even amongst those who are more vulnerable, the rate of long-term sequelae is low. It’s the people who end up in the ICU who are experiencing the most long-term effects, and those people are a single-digit percentage of a single-digit percentage of those infected.
I want to believe it, but optimism and certainty given the novelty of this virus seem strange bedfellows.
The threshold to herd immunity depends upon contact rate. So interventions well short of "lockdown" may not completely prevent the spread of the virus but still reach equilibrium at a lower number of people infected.
Sacrificing lives unnecessarily to “save the economy” is perverse in that the economy is supposed to serve us, not the other way around.
I’m not saying we should stay in lockdown forever, but I’d rather our leaders think creatively with a default view of “let’s be cautious with a global pandemic that has so far shown great destructive powers when left unchecked”.
But when I talk about "the economy", I mean the process that puts food on plates and electricity in houses. Someone has to grow the food, someone has to transport it, someone has to store it, distribute it. Sure, we could round up the world's billionaires and force them to do that, but unfortunately there aren't enough of them to do it for everyone, so someone else will have to do it too. And someone will have to service the cars and trains those workers take to get to work, and someone will have to watch their kids, and someone will have to provide toys to the people watching their kids, etc. etc. etc. THAT'S what I mean by "the economy".
Fewer than 300,000 people have died with nexus to Covid. Even if that population were to double, we're left with 0.0066% chance of death. It's great to be legitimately concerned, but those are good odds as far as I'm concerned.
What's an acceptable risk for you?
This disease has the potential to kill 3 million Americans, 70 million people globally, and that’s only if we spread it out.
Why aren’t we all sacrificing so that the poorest, most vulnerable population can have sufficient funding so that they will have a roof and food and clothing? Why isn’t the federal government sending monthly checks? Where’s my tax increase? Where’s why aren’t I being drafted to work in health care or food delivery?
All our government has asked of us, begrudgingly, is to stay inside for a while, and we can’t even do that without whining.
This is looking less and less likely. With increasing evidence that the infection fatality rate is 0.6%, and that the herd immunity threshold may be somewhere around 30% infected, it's more like 700k. Still catastrophe, but 1/4th the catastrophe you imply...
> All our government has asked of us, begrudgingly, is to stay inside for a while, and we can’t even do that without whining.
I favored sheltering before everyone else. It was a good way to blunt the incident wave of the epidemic and prevent health care overload.
At this point, Rt with the current intervention isn't low enough to ever get us to a regime of extreme containment in any reasonable/attainable amount of time, and there's too many jurisdictions that are hotbeds of the virus that will just reintroduce it. I am not convinced that the current strategy saves lives in the long term.
It even risks backing us into a corner, where we have no choice but to reopen more than we'd like, and then face a devastating fall season with little population immunity and no seasonal factors on our side. Especially in locations like the SF Bay Area, under the nation's strictest health order but also with a very low per capita case load.
Worse, it's hard to be sure the intervention is even effective. Looking at data series on https://rt.live , there's no obvious inflection or discontinuity relating to sheltering or relaxing of sheltering in the individual states' series. Rt was falling before sheltering, and continued to fall at a comparable rate afterwards...
Not long-term outcomes. (And even short-term our data is not "very good" because we still have no idea what the actual infection rate is.)
> Many people think COVID-19 kills 1% of patients, and the rest get away with some flulike symptoms. But the story gets more complicated. Many people will be left with chronic kidney and heart problems. Even their neural system is disrupted. There will be hundreds of thousands of people worldwide, possibly more, who will need treatments such as renal dialysis for the rest of their lives. The more we learn about the coronavirus, the more questions arise. We are learning while we are sailing. That’s why I get so annoyed by the many commentators on the sidelines who, without much insight, criticize the scientists and policymakers trying hard to get the epidemic under control. That’s very unfair.
https://www.sciencemag.org/news/2020/05/finally-virus-got-me...
Facts: in the US, the hospitalization rate for covid is around 4.6 per 100,000. It’s half that for people under age 50. The rate of serious disease is very, very low...and this includes high-risk groups:
https://www.cdc.gov/mmwr/volumes/69/wr/mm6915e3.htm
> some significant percentage of the population is going to have a negative impact
Is there any evidence at all that this is some kind of feature of this disease? It's even starting to look like most people who become infected never even develop the associated disease.
A fair number of people with SARS-CoV-1 ended up with chronic fatigue ailments, etc, afterwards, too.
We don't know, but there's almost certainly going to be more lasting morbidity from this epidemic than the common cold. If it's a little bit, it doesn't change the calculation much. If 1/4th of those hospitalized develop significant morbidity though, that sucks.
Sure. And the other ones kill.
> If 1/4th of those hospitalized develop significant morbidity
Am I wrong, or is it that the overwhelming majority of people who are hospitalized already have a comorbidity? Where does 1/4 come from? Why not 100%?
In other words, hunkering down won't really change the fact that the vaccine, if it comes at all, won't come in time.
And regarding the risks, one of the scientists who discovered Ebola [0]:
"Many people think COVID-19 kills 1% of patients, and the rest get away with some flulike symptoms. But the story gets more complicated. Many people will be left with chronic kidney and heart problems. Even their neural system is disrupted. There will be hundreds of thousands of people worldwide, possibly more, who will need treatments such as renal dialysis for the rest of their lives. The more we learn about the coronavirus, the more questions arise. We are learning while we are sailing. That’s why I get so annoyed by the many commentators on the sidelines who, without much insight, criticize the scientists and policymakers trying hard to get the epidemic under control. That’s very unfair."
Also based on Japanese study on around 100 COVID-19 cases from Grand Princess passengers [1] and some 6 divers all with mild cases from Germany [2] around 50 to 80% of people seem to have damage to the lungs visible on CT scans after mild symptomatic or even asymptomatic infection. Two of the divers had significant oxygen deficiency when doing physical exercise after 5-6 weeks of recovery. The guess of the doctor who was inspecting them is that this is permanent damage that may take years to recover if ever.
[0] https://www.sciencemag.org/news/2020/05/finally-virus-got-me...
[1] https://pubs.rsna.org/doi/10.1148/ryct.2020200110
[2] https://translate.google.com/translate?sl=auto&tl=en&u=https...
Case in point 'There will be hundreds of thousands of people worldwide, possibly more.' Taking 'hundreds of thousands' to be 500,000 and 'number of people worldwide' to be 8,000,000,000, we get 0.006% people with long term adverse side effects. This is much less than 1% we assume are going to outright die. Is this ballpark even remotely accurate? Do we have reliable clinical / epidemiological data to ballpark this number? Do models have any credibility left after being adapted on-the-fly by an order of magnitude or more?
As of the Grand Princess / 6 divers scenarios, something doesn't add up. Either 50% of people [in context, 4 billion] are going to end up with serious long term oxygen deficiency or not. If this is indeed the case, I don't understand why the medical community doesn't explain in more stern terms the severe [Black Death lite] long term implications. Given the implied severity, why don't we have a Manhattan project to replicate these studies, in every single developed country out there? Drop everything else you are doing, pick a 10,000 sized city with a sizeable outbreak and CT everyone in that city, repeatedly. Send the Army if you have to.
Our current best prediction is that 596 million people will get infected (247M-1.4B 50% CI) before the end of the year and that only 16 million (8.0M-36M 50% CI) will be reported to WHO. We expect also 1.74 million deaths (532k-6.0M 50% CI) world wide before the end of 2020. Overall infection fatality rate is likely to be 0.8% (0.5-1.2 50% CI).
And, I agree with you - we should have had massive projects for track and tracing already in February, but politicians almost everywhere dropped a ball on this besides Taiwan, South Korea maybe Germany and some other countries. In many places there are still no good exit plans.
Also, scientific community is slow to do anything. Masks are good example of that - making a masks at home costs nothing, so if widespread use of homemade masks have a chance to save lives and reduce length of lock downs even by days then the risk-cost-benefit analysis is just overwhelming in favor of widespread mask use. But medical community wants controlled trials and tip-top evidence before trying anything even if it's as simple as a mask.
Overall there seems to be a sort of fog of war going on.
From my perspective the models never had any credibility due to the fact that small errors in model parameters lead to exponentially big errors in predictions. Also, soon after China managed to contain the outbreak it became more or less obvious that human behavior is the biggest unknown in all epidemiological models. No model is able to predict how politicians and society will react.
Here is my comment from 3rd of March [2]: > I think very important part of a model that intends to give real world prediction would be ability to model what happened in China. There needs to be something in the model that allows to slowdown the growth of infection.
Thankfully, big political decisions were never only based on models. They were based on 1. empirical data from SARS outbreaks in China, later on based on China and Italy experiences 2. simple common sense computations like around 20-80% of population can get it if we do nothing (Swine Flu or Spanish Flu) and 0.5-2% of infected can die based on Grand Princess and Chinese data. So the best case scenario assuming no reaction and wide spread like with Swine Flu or Spanish Flu is 0.1% of population dieing and the worst case scenario is 1.6% population dieing. It was obvious that reaction was needed given the severity of the best case scenario with no reaction.
I think what got missed is the fact the people across the world were already starting to react by themselves in early March soon after Lombardy went into lock down. You can see that in Google/Apple Mobility data and in Open Table restaurant reservations. People miss that piece of data even now as lock downs are lifted.
Regarding 50% - this is what shows up on CT scans. The paper does not provide much of interpretation of that scans. But seems like we can indeed expect reduced lung capacity at least soon after recovery in some nontrivial percent of the population. That much we know, the long terms effects are just a guess. I will probably try to make a quest...
How do you use this in places where transmission is less than 1? New Zealand now has a transmission rate considerably under 1, but this seems to break the calculation.
Does this mean that a reproduction number under 1 doesn’t need herd immunity? We do, because we can’t stay locked down indefinitely, and presumably our rate will go up when we relax restrictions.
Meaning, let the young and stupid go out and play, it will allow for herd immunity at a lower rate than the typical randomly distributed rate.
What is that again?
It does indicate the Swedish model could work, because the paper says it's just 43% with "disease-induced" herd immunity. And according to Swedish authorities 25% of Stockholm population already has antibodies.
Being a resident Swede, my lasting impression is that the so-called "strategy" has two legs (can be backed by a long list of official statements) 1: hope that the virus does not hit, and if it does, that it is not necessary to do anything and/or it is already too late anyway and that hopefully it will disappear through herd immunity. A hope that has been expressed up to twice weekly for the last 2 months or so, while the number of deaths go up and up. And 2: in a manner typical of governmental agencies everywhere: never ever admit to any mistake or error in judgement. Like admitting that the recommendation for the public not to use face masks was wrong, and was brought on by secondary concerns (over availability in hospitals). Even now (as of yesterday) the official stance is that using face masks might increase risks and efficacy is not backed by "scientific proof".
The paper should probably be seen in this light. The main author of the paper Tom Britton forms together with Giesecke and Tegnell the "herd immunity" triumvirate that is responsible for the Swedish mess that currently renders Sweden a place among the top 10 countries with most fatalities per million. At the face of it this paper just seems to confirm that protective measures actually work. But by shining the light the herd immunity aspect of the equation he makes it sound like they were right all along.
[0] https://mackuba.eu/corona/#compare?val=d&align100=1&pop=1&c=...
Herd immunity is horrible word, and none wants to use it anymore. But because flattening the curve does leave the virus linging around, it in many practies is same as "flatten the curve" as pointed by epidemologists:
> The "Flatten The Curve" plan was touted by every public health organization, while the United Kingdom's original "herd immunity" plan was universally booed. They were the same plan. The UK just communicated theirs poorly.
[1] https://ncase.me/covid-19/
The duration of immunity for other corinaviruses varies quite a bit, the disease has the potential to cause permanent respiratory damage, with uncertain consequences for the possibility of reinfection, and we’re still seeing novel symptoms arise as in the case of the children with Kawasaki-like inflammation in NYC.
I get the strong desire to return to a normal state of affairs, but paving over reality with scientific notions, deployed pseudoscientifically, does very little to get us there.
How do we “know” either of those facts? You may well be right, but I don’t see a scientific consensus yet.
https://www.technologyreview.com/2020/04/27/1000569/how-long...
Nowhere is this stated or suggested. Why are you saying that it is? The only point it makes (contrary to all your claims) is we don’t know the duration of immunity and the situation is unpredictable, based on what we know of other coronaviruses. From the article:
>What I have been telling everyone—and no one believes me, but it’s true—is we get coronaviruses every winter even though we’re seroconverted,” says Matthew Frieman, who studies the virus family at the University of Maryland. That is, even though most people have previously developed antibodies to them, they get the viruses again. “We really don’t understand whether it is a change in the virus over time or antibodies that don’t protect from infection,” he says.
> After testing different scenarios, the Harvard group concluded that their projections of how many people end up getting covid-19 in the coming years depended “most crucially” on “the extent of population immunity, whether immunity wanes, and at what rate.” In other words, the critical factor in projecting the path of the outbreak is also a total unknown.
The figure for immunity duration at say 95th percentile seems to be the key figure for herd immunity being viable or not, at least to my layman eyes.
Please stop adding certainty where it is unwarranted. Either supply citations to expert authorities, or be quiet. Otherwise you're just spreading misinformation.
It seems to me that you're right, we can't know for certain until many years later, but in the meantime the world goes on, we can't all just cryogenically freeze ourselves. The best we can do is make educated guesses based on previously existing coronaviruses.
I’m not sure why people can’t seem to fathom that we are still very early in our understanding and experience of this disease, no matter how dramatic its consequences thus far. There’s no way to accelerate things through false confidence or other forms of denialism.
There's also no way to decelerate things through false humility. We're in an urgent crisis, so we must make decisions now based on whatever evidence is available; there's no position of safety we can retreat to while waiting to learn more.
[1] https://www.businessinsider.com/coronavirus-fauci-those-who-...
[2] https://www.bbc.com/news/health-52446965
Has anyone here done the research that we can use as a reasonable prior? My assumption was those diseases all produce long lasting antibodies.
https://www.technologyreview.com/2020/04/27/1000569/how-long...
Also, FWIW, if getting the actual disease doesn't generate sufficient antibodies to confer immunity, being dosed with a vaccine wouldn't either. Whether vaccine-supported or not, herd immunity is the most likely outcome (unless the disease becomes endemic instead). What remains to be seen is how many people have to get ill to get there.
Is it outrageous to think R0 could be 3.5 in NYC but 1.5 somewhere else?
No, not at all. It would be outrageous to think that it doesn't vary by a factor of two IMO.