Is it standard to report antibody concentration in μg/ml? How likely is it to deliver the reported IC50 to the lung? Also do antibody typically not have cytotoxic concentration because of their specificity?
> The antibody known as 47D11 targets the spike protein that gives the new coronavirus a crown-like shape and lets it enter human cells. In the Utrecht experiments, it didn’t just defeat the virus responsible for Covid-19 but also a cousin equipped with similar spike proteins, which causes Severe Acute Respiratory Syndrome, or SARS.
> Monoclonal antibodies are lab-created proteins that resemble naturally occurring versions the body raises to fight off bacteria and viruses. Highly potent, they target exactly one site on a virus. In this case, the scientists used genetically modified mice to produce different antibodies to the spike proteins of coronaviruses. After a subsequent screening process, 47D11 emerged as showing neutralizing activity. Researchers then reformatted that antibody to create a fully human version, according to the paper.
I don't have any biology background - are you saying this targeting might not work?
They are saying that targeting can be not exclusive for example an antibody that targets the spikes might also bind with the receptors they connect too.
The antibody recognizes a particular 3D shape on the virus, called an epitope. There is a chance that a similar shape exists in humans, and using this antibody would cause your immune system to attack itself.
https://en.wikipedia.org/wiki/Molecular_mimicry
The antibody fits the spike protein like a lock and key. They key might fit other locks in humans with varying degrees of fit, on other cells in the body.
There are two such lock-and-keys on the antibody, the other key fits the immune system cells, that start a cascade that amplifies the immune response.
Even if it is a weak fit for an unintended target, the response can be an issue.
I once saw a good talk that mentioned that -any- drug has a chance to be adversial. Drugs that work on most people might make another sick. This is indeed why there is so much testing and careful indexing side effects.
Yes, a vaccine MAY be possible, but the news reports I'm hearing are wildly optimistic at best. It will also take an enormous amount of energy/willpower to quarantine until then.
It might be more economically efficient (and convenient) for the strong and healthy to purposefully self-infect, and build up anti-bodies naturally. Herd immunity will eventually be built and corona will no longer be a problem.
Doesn’t matter - a good portion of the US will never accept contract tracing, a prolonged shut down, mandatory antibody testing, or forced vaccination. It is illegal for states to prevent persons from neighboring, more constrictive states from traveling in and out. Given the Supreme Court make up it is unlikely any of the above would be upheld as constitutional. Therefore the US is heading toward a herd immunity strategy regardless of what technocrats think the end game will be.
I laugh when I hear people talking about a vaccine. We can’t get people to vaccinate for diseases like measles that spread faster, are deadlier, and kill kids.
MMR (measles is one of the M) vaccination rates are plenty high enough to get us to herd immunity for SAR-CoV-2 (we need something like 70% of the population being immune).
Even in states with the worst coverage. It's closer to 90% in most of the country:
I think you make excellent points in the first paragraph.
As for the second:
>I laugh when I hear people talking about a vaccine. We can’t get people to vaccinate for diseases like measles that spread faster, are deadlier, and kill kids.
The relationship between immunity rate and effectiveness is not linear. It's be nice if we could vaccinate the anti-vax folks, but we don't actually need them to get massive gains from vaccinating part of the population. Rates as low as 70% would be incredibly helpful.
I've also wondered about the end game and so far concluded that most societies (including the US) would go the vaccine route (which confers herd immunity) as opposed to natural immunity (what I think you mean by "herd immunity"), but I would love to hear what you think.
The reason why I doubt the end game is herd immunity via natural infection is:
* millions would die
* health systems would get crushed
* the virus is unlikely to disappear entirely, so would simmer around the world, triggering epidemics every few years or so.
We may not have a choice, in that we're not guaranteed to have a useful vaccine in massive doses anytime soon.
But rebutting your individual points:
> millions would die
Unlikely. Improved estimates (thanks to serological data) for infection fatality rate range from 0.3% to 0.5%. If we can protect the most vulnerable populations, we can have a lower death rate than this-- e.g. in the under-30 crowd, the risk of hospitalization is 1 in 500 and the risk of death a tiny fraction of this (1 in 5000 or less).
Further, any variance of susceptibility or contact density means you don't need to reach 60% for herd immunity. Some estimates say that the real threshold may likely be 25% or less: e.g. https://www.medrxiv.org/content/10.1101/2020.04.27.20081893v... Further, lighter weight social distancing measures can further reduce Rt and attain herd immunity at a lower percentage.
If you assume we need 40%, and 0.25% IFR from protecting the most vulnerable-- you come up with 328k deaths. This is bad, but less bad than many alternatives. Note that the shorter lived the controls protecting the elderly and other vulnerable people, the more effectively we can protect them, too.
> health systems would get crushed
We'd not want to do what New York did, but let's look at it as an example. New York's health care system (barely) sustained the load. Now they're very possibly most of the way to herd immunity in NYC. Yes, we'd like to flatten the curve a bit from this and be better prepared.
> the virus is unlikely to disappear entirely, so would simmer around the world, triggering epidemics every few years or so.
The long term immunity question is interesting. Of course, vaccines could help improve this picture even if one ends up with disease-spread based herd immunity.
My personal belief is that A) total antibody-based immunity will last a few years, based on our experience with SARS-CoV-1; B) partial antibody-based immunity will likely last longer than that; C) memory B cell / T cell based immunity is likely lifelong and makes any subsequent course of disease less severe.
That is, I think it's likely that the current human coronaviruses that cause the common cold might very well cause a high death rate and be very transmissable if exposed to an immunologically naive population.
Of course, your third point holds even more true when it comes to interim suppression and containment efforts while we isolate and wait for a vaccine. It's an even more intractable issue to try and maintain suppression when the vast majority of the population is still susceptible.
> Unlikely. Improved estimates (thanks to serological data) for infection fatality rate range from 0.3% to 0.5%.
This seems optimistic. I did the math last week, and 0.2% of New York City had died either from the coronavirus, or from something that was probably the coronavirus. About 21% percent of New York City was testing positive for antibodies. (Both deaths and antibodies are lagging indicators of infection, although a noticeable fraction of the deaths lag by quite a bit.)
That would give us an IFR around 1%. If we needed to have two-thirds of Americans catch the virus to reach herd immunity, that would be about 2 million dead. With any luck, some people are already immune. And as you point out, variation in susceptibility may stop things earlier than that.
The are some nasty side-effects in some percentage of survivors: Impaired breathing and damage from blood clots seem to be two of the most frequently mentioned, and Wuhan is apparently seeing a spike in dialysis patients.
The CDC is predicting 3,000 deaths/day in the US by June 1st. This seems plausible: We'd only need a few other metro areas to have a NYC-style spike.
So far, several countries do seem to be able to control the virus. But at this point, I increasingly fear that the US will not be able to do the same. We don't seem to be able to ramp up testing, and we haven't gotten the infection rate down to the point where contact tracing would work. And significant portions of the US seem to be giving up on control and going for a herd immunity strategy.
> About 21% percent of New York City was testing positive for antibodies.
From samples returned 10 days ago, so add a bit more lag.
It's not beyond the realm of possibility that New York City has reached the herd immunity threshold. The biggest estimates of variance in contact networks and susceptibility (from fitting to case count data) predict a herd immunity threshold of ~15%. (Cited above).
> We don't seem to be able to ramp up testing
Testing, shmesting. It only provides a minimal adjustment to Rt; sensitivity isn't great, and you can't test everyone every day.
> we haven't gotten the infection rate down to the point where contact tracing would work
Nor will we. The most aggressive lockdowns produce case count decays of 40% or so per week-- possibly less. The suggested threshold for where contact tracing can work well is 1 infection per million population. The SF Bay Area probably has about 3500x that. -ln(3500)/ln(0.6) =~ 16 weeks.
IHME was predicting the virus would magically go away in California with continued shelter in place in the next 3 weeks. They just backed away from this crazy prediction that the data has never fit. However, policymakers depended upon it in making the tradeoff: aggressive policies aimed at control could be justified if they'd really get us to a sustainable containment regime in a couple months.
> And significant portions of the US seem to be giving up on control and going for a herd immunity strategy.
In the end, the only long term paths are to radically change our way of life forever, or herd immunity. There's only really one vaccine effort that could deliver tens of millions of doses to North America by mid-2021, and that's the Johnson & Johnson program. Odds of that program's success are 50-50 at best.
> I did the math last week, and 0.2% of New York City had died either from the coronavirus, or from something that was probably the coronavirus
"Something PROBABLY was the coronavirus?". So you're from the camp of "someone was shot 9 times, so he died from corona virus". I question the way you calculate the numbers.
Ascribing all excess deaths to coronavirus is a mistake. People are avoiding ERs and doctors; the incidence of typical CVA, MI, etc, in hospitals is way down. Not because we're having fewer CVAs and MIs, but because people are dying at home instead of being treated.
(Prolonging the epidemic increases the number of people who will die this way, too).
> Ascribing all excess deaths to coronavirus is a mistake.
I worded my statement intentionally.
> It's also most likely still an undercount
Some of the excess deaths will be other things. It will take more careful analysis to come up with reasonable breakdowns, and what percentage is likely covid-19 deaths.
> “I think people need to be aware that the data they’re seeing on deaths is very incomplete,” said Dan Weinberger, a Yale professor of epidemiology who led the analysis for The Post.
> Those excess deaths — the number beyond what would normally be expected for that time of year — are not necessarily attributable directly to covid-19, the disease caused by the coronavirus. They could include people with unrelated maladies who avoided hospitals for fear of being exposed or who couldn’t get the care they needed from overwhelmed health systems, as well as some number of deaths that are part of the ordinary variation in the death rate. The number is affected by increases or decreases in other categories of deaths, such as traffic fatalities and homicides.
> But excess deaths are a starting point for scientists to assess the overall impact of the pandemic.
> People who did not have a positive COVID-19 laboratory test, but their death certificate lists as the cause of death "COVID-19" or an equivalent.
Since tests are scarce, they're not necessarily being used to confirm people who died at home or who died during triage. But COVID-19 is pretty distinctive, and in any case, the COVID-19 deaths are only a portion of the excess mortality.
The study that showed 21% positive antibody results came from self-selected testing of people physically shopping at grocery and big-box stores. Unfortunately, that ultimately doesn't effectively represent the overall population of NYC at all. This was posted by the Head of Decision Intelligence at Google about the study a day after the "21%" headline was published: https://towardsdatascience.com/were-21-of-new-york-city-resi...
> Unfortunately, that ultimately doesn't effectively represent the overall population of NYC at all.
Yes, as the Google article points out, the study is probably an undercount. IIRC, the samples were taken from mid-day grocery shoppers. If so, this would push the real NYC IFR higher, possibly into the 2% range. And as the Diamond Princess has shown, the real IFR continues to climb for weeks, as the final ICU patients succumb.
This would make the ultimate costs of herd immunity higher.
> Further, any variance of susceptibility or contact density means you don't need to reach 60% for herd immunity. Some estimates say that the real threshold may likely be 25% or less: e.g. https://www.medrxiv.org/content/10.1101/2020.04.27.20081893v.... Further, lighter weight social distancing measures can further reduce Rt and attain herd immunity at a lower percentage.
> It is true that if you could somehow pick and choose who became immune — the way you can in principle with vaccination — you might be able to do pretty well, vaccinating the high-contact individuals only and reaching herd immunity at low levels of vaccination.
> But natural infections don't spread like this. High-contact individuals are connected to low contact individuals. An epidemic spreads organically through the population, infecting who it happens to, not who you want it to.
> IF high contact individuals were only connected to other high contact individuals with high probability, you still might make some headway with nature disease progression. This sort of thing can matter for STD transmission.
> Respiratory viruses tend to be different. You have household transmission, cohort-based (school/work) transmission, and incidental transmission (subway/supermarket).
These render the transmission network quite well-connected.
Additionally, if we're talking natural infection to get to herd immunity, you have the issue of overshoot, so unless you're very precise on measures to tamp down on transmission before you get to herd immunity levels, you easily overshoot the herd immunity threshold by quite a bit.
> > But natural infections don't spread like this. High-contact individuals are connected to low contact individuals. An epidemic spreads organically through the population, infecting who it happens to, not who you want it to.
Surely high contact people are infected -more-, though, no?
In many ways, R0 is a "somewhat worst case number", in that it's something you observe in a population where the virus propagates well. There are likely to be other populations that it doesn't spread quite so well in-- either because of innate susceptibility or behavior differences.
> Additionally, if we're talking natural infection to get to herd immunity, you have the issue of overshoot, so unless you're very precise on measures to tamp down on transmission before you get to herd immunity levels, you easily overshoot the herd immunity threshold by quite a bit.
Exponential processes with a lot of delay and noise are a difficult controls problem, but it wouldn't be hard for jurisdictions that are doing well to target Rt=~ 0.95 .. 1.1 with interventions instead of trying to maintain Rt =~ 0.8. Of course, you need to be prepared to react quickly if things look like they are getting out of hand. And, thankfully, as the susceptible population drops the control problem gets a lot easier, because there's a ceiling of how high Rt can get...
Your personal belief about medium-to-long-term immunity is contradicted by research on same with SARS; see “Lack of Peripheral Memory B Cell Responses in Recovered Patients with Severe Acute Respiratory Syndrome: A Six-Year Follow-Up Study"
[pdf] https://www.jimmunol.org/content/jimmunol/186/12/7264.full.p...
From the abstract of your source: "Memory T cell responses to a pool of SARS-CoV S peptides were identified in 14 of 23 (60.9%) recovered SARS patients, whereas
there was no such specific response in either close contacts or healthy controls."
Correct - there was a long-term memory T cell response. However, see sentance immediately preceeding the one you quoted - basically SARS-CoV IgG antibodies ("IgG Ab" below) were totally absent 6 years after infection. So, antibodies against SARS are not produced long-term, unlike many other types of viral infections, and unlike the desired mechanism of most vaccines.
"Six years postinfection, specific IgG Ab to SARS-CoV became undetectable in 21 of the 23 former patients. No SARS-CoV Ag-specific memory B cell response was detected in either 23 former SARS patients or 22 close contacts of SARS patients."
K. Thanks for "refuting" a comment where I said "total antibody-based immunity will last a few years, based on our experience with SARS-CoV-1" with evidence that antibodies are gone several years later. :P
No no, thank YOU for "refuting" my "refutation"! I do stand corrected, I did not internalize your "total antibody-based immunity will last a few years" sentance, and was focused on the following "memory B cell / T cell based immunity is likely lifelong".
Furthermore it seems as if mutations to the spike gene unique to hCov-2019 somehow is involved in suppression of immune systems’ ability to properly regulate its inflammation response; specifically, it seems to mess with the correct functioning of “M2” macrophages that act in a wound-healing mode to regulate the activity of proinflammatory “M1” macrophages. This leads to a runaway inflammation response.
The antibodies described here need to be tested en vivo (monkeys perhaps) to make sure they don’t actually lead to worse pathology (which for hCov-2019 seems to be immune mediated rather than directly caused by virus)
See my Twitter feed for references, I’ve been tweeting an immuno lit review (@100ideas).
Here's the reference: Liu 2020 "Anti-spike IgG causes severe acute lung injury by skewing macrophage responses during acute SARS-CoV infection." https://doi.org/10.1172/jci.insight.123158
I do think a vaccine will be made available and likely sooner than anyone is predicting, but it will not be mandatory and if states or employers try to make it mandatory they will held up in lawsuits for years.
I could see a future where, like the flu vaccine, everyone is encouraged to get a SARS COV2 vaccine and there will be reasonable compliance.
Hospital systems were only really crushed in there places, Lombardi, NYC, and Spain. Only in Lombardi Italy did hospitals actually run out of beds (go over capacity). Even in London today the hospitals are under capacity. I am not saying this is a good yard stick to go by, I am pointing out that outside of three locations most hospitals are sitting virtually empty. Therefore it is unlikely health systems would be crushed.
As far as millions would die, again I would say look to the mortality rates outside of the three outlier areas (Lombardi, Spain, and NYC) and the mortality is far below 1%. I can see a future where COVID kills as many people as the flu. I don't see a future with a crushing mortality rate.
Viruses rarely disappear entirely, but the mortality rate is not high enough to be so afraid of it. It spreads fast, but not as fast as measles, whooping cough, or TB, which spread faster, kill more people, and also kill children. We try to eradicate those diseases for a reason. Covid is nowhere near their level. If we set the bar this low, we will be stopping the world economy every decade to fight viruses that bubble up and kill comparatively few people.
The infection fatality rate of someone in there 20's or even a teenager is basically a rounding error. The strong and healthy dying are the exception, not the rule.
Did we ever get any good information on the rates of permanent lung damage or hospitalization for young people? I feel like over-focusing on fatality could cause us to overlook the more pragmatic risks.
Everyone is going to catch this. A vaccine will not exist for another year. The world can’t be shut down for another year. When everyone eventually catches this, some will have permanent lung damage. That sucks. Pretending this isn’t going to happen is foolish.
If we get the case count low enough we can open up and do contact tracing until the vaccine arrives or it's eliminated... if we open up before it's that low, everyone gets it.
Not always. COVID-19 was described as “mild” at the outset. Turns out their operational definition of “mild” was something like “doesn’t require a trip to the ICU even though it may require hospitalization.” Not everything you read will use the word “mild” in its conventional sense.
Mean age on Diamond Princess was 62, and the paper doesn't break lung damage up by subpopulations like "younger people" so it's hard to generalize. But I'm not blase.
Plenty of comments implying that we're "all going to get it", which may be pretty much true in some areas in the US and Europe. I'm still holding out hope that being in Australia we may get a handle on it (although we just saw a huge cluster in a meatpacking plant). It's interesting to think that we might be heading for a world where some countries have had 60% prevalence and others have had 0.6% prevalence - what does that do for travel, trade, migration, tourism - all that stuff?
It's impossible to tell just from imaging a month or two down the road how "permanent" damage is. Yes, it's concerning. But we also don't know that it can't heal in time. Just because it looks like things we "know" on a CT doesn't mean we know how it acts long term.
Before you downvote me, think about all the reports of people with VERY low oxygen saturation that "shouldn't be" alert, talking, and feeling ok. That goes against everything we "know" as well, but it's very real for this disease.
I'm not going to go get permanent lung damage and spend weeks in the ICU just so we can reopen the economy. The IFR is one thing but the long-term effects of this illness are severe. Frankly the idea that we younger people should "go take one for the team" is as unconscionable now as it was when the older generation started the Vietnam war draft.
How long until the ICU has drained the queue of supplies and tools that we forced the economy to stop producing? I don't think the government has enough visibility into that supply chain to reopen it in a way that works without the rest of the economy.
A "few weeks on the ICU"? Oh come on, that's melodramatic for the great bulk of the cases if you are healthy. You aren't going to spend "weeks" on a ICU, believe me.
self-infect and self-quarantine, so you won't accidentally spread it to the immune repressed or grandma or whatever. Not only is this not "unconsciounable", I think the opposite. I have great respect for people who put themselves out of their way to protect other, less fortunate people.
In case anyone is thinking similarly, remember that vulnerable people (old people)'s social networks are mostly other vulnerable people. Even if herd immunity was "achieved" in the younger cohort, the old would be at basically the same level of risk because if one old person gets infected, it'll spread through the unprotected social network quite easily. You need it to be well mixed to be effective.
That all being said, if theories of initial viral loads making a difference are true, it's not that crazy to imagine individuals choosing to self infect with a very small initial viral load so they can just stop needing to tip toe around life with the concern that they infect others, while continuing to isolate on their own. If I lived alone I'd be tempted.
You need to balance not jut your chance of death, which is low if you’re very young, but your chances of getting very very sick. Spending a few weeks in the ICU is a good way to bankrupt yourself on the path towards returning to regular work, let alone how hard a ventilator is on even survivors.
Plus, we have no idea what happens to the infected a few years or a decade from now. If given the choice, not getting sick at all is the best possible outcome.
> Spending a few weeks in the ICU is a good way to bankrupt yourself on the path towards returning to regular work, let alone how hard a ventilator is on even survivors.
Ok, I'm willing to consider devil's argument, but this is just plain ridiculuous. The great bulk of infected people classsify this as "mild". If you're young, strong, and healthy, your chances of dying from this are basically zero in any common sense way. And far more people are going to "get bankrupt on the way to work" as you say using the current method. We're not trying to find a perfect solution, we are trying to find the better one.
> If you're young, strong, and healthy, your chances of dying from this are basically zero in any common sense way
There are zero longitudinal studies about the long-term effects of infection. For all we know, young healthy people could appear to beat the virus, only for it to hide out and plague you with severe health problems down the road. We could have an massive epidemic of a neurodegenerative disease caused by Covid-19 twenty years from now.
I have no desire to roll the dice on that even if the odds look good for me at the moment.
The "conspiracy" theory is the news often exaggerates or gives misinformation on a particular subject to fulfill a particular agenda or make more money on ads.
> In 80% of known cases, COVID-19 causes mild to moderate illness, according to a report of a joint World Health Organization-China mission of 25 infectious disease experts held in China late last month.
> At a press conference on March 9, Maria Van Kerkhove, technical lead of the WHO Health Emergencies Program, said: "[A] mild infection starts normally with a fever, although it may take a couple of days to get a fever. You will have some respiratory symptoms; you have some aches and pains. You'll have a dry cough. This is what the majority of individuals will have."
> It is "nothing that will make you feel like you need to run to a hospital," says Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security.
> A mild case of COVID-19 in and of itself is not dangerous.
I don't know why you would think the risk of death is dependent on age but the risk of severe illness is not. Age affects both. You're highly unlikely to get put in an ICU if you're young. It would be pretty improbable for a disease like this to have long term consequences unless you start going hypoxic and have organ damage. not impossible, but probably a low concern.
Yeah, let herd immunity kick in so it's harder for the virus to spread and then STRICTLY quarantine the old. As in much stricter than what they have now. I realize that's not great for grandma, but at some point, society has to make a reasonable tradeoff. If you're young, strong and healthy, your probability of dying from it is basically a rounding error.
We have no reason whatsoever to think infection doesn't confer immunity. All other human-infecting coronaviruses do. And with no confirmed cases of reinfection yet, there is no evidence showing that this virus breaks the norm.
Herd immunity is easier said than done. A portion of the people who become infected require medical intervention, and many parts of the US medical system are inadequate to meet this need. It will take years to get to herd immunity levels through any kind of controlled infection alone, and many will die.
Anywhere on those maps that show red indicates people dying due to hospital resource exhaustion, either from COVID-19 or unrelated health issues. To a lesser degree this is happening in yellow areas as well.
And ProPublica is only considering beds! Medical personnel, supplies and equipment are finite resources as well. Personnel cannot handle 18 months of 200% bed utilization, and they don't have the PPE they need as it is.
There is no easy fix to this situation; we are facing the kind of problem that is best met with thorough preparation, but unfortunately we don't have that.
The government can print money, and implement programs to distribute food and other necessities. They can't print tests or masks or vaccines -- once the resources are put in place, it simply takes time. Realistically, it will be a long time before even one of those three things is in a good place. Probably not this year.
A more achievable goal than herd immunity is to find a workable way to reduce the number of viral carriers and limit transmission while we wait for the tests, masks and vaccines that we need to get society back on track. That requires leadership and coordination, but it especially requires us to accept the seriousness of the situation and behave responsibly.
The big question about natural herd immunity is really how far the disease has already spread and what that means for true IFR.
If New York has "survived" this wave tolerably and 20% of people are immune, they may well be a quarter of the way to herd immunity. Which is still a lot of suffering to go, but it's also not going to take 18 months of 200% hospital bed utilization either.
1) The healthcare system barely handled the load, and that was with heroic efforts to reposition ventilators and build up temporary capacity. We barely handled it because most of the country was not nearly as hard hit, so we could still shift resources around. If everywhere was hit this hard at the same time, that would be a different story. It would need to be spread out more than you imply if we wanted to have all of the country trying to stay just below capacity.
2) New York City has lost .2% of their entire population to get to that ~20% number. Extrapolated out, that's once again back to the 1-2 million deaths range for the country to hit herd immunity.
My guess is that it will be the same thing like swine flu 10 years ago. The media will print out a sensationalized number, and the real numbers will end up being 10x fewer when calculated honestly.
The 2009 H1N1 Pandemic killed in the ballpark of 10k people in the US. I don't recall ever seeing mainstream news outlets reporting in the ballpark of 100k recorded deaths.
It's been 7 weeks since the Imperial College model that predicted up to 2.2 million deaths in the US, that used an infection fatality rate of 0.9% as an assumption. The best science still has us in the 0.5% to 1% range for IFR, still putting us in the 1-2 million range if let ourselves get to herd immunity levels without a vaccine.
I think we'll avoid getting to 1-2 million, but it'll be because we take actions along the way to push some/most infections to post-vaccine or post-effective treatments.
> Try to reach it without a vaccine, and millions will die.
We are going to have nowhere near 1-2 million deaths from this. and the IFR range is around 0.2%, not 0.5 - 1%.
And of course we will get herd immunity soon, with the way exponentials work. We are re-opening the economy! We will reach herd immunity far quicker than we will get a vaccine.
>It might be more economically efficient (and convenient) for the strong and healthy to purposefully self-infect
If someone told me I should deliberately catch a cold I'd say no. What about Ebola? I'd say no! A germ that I don't know? I'd say no!
If a police patrol arrived somewhere and someone ran away, that person would be suspicious. If I'm asked to get any germ I'd suspect that it's very dangerous, even if it was just a cold.
So telling people to infect themselves deliberately won't work.
Yeah, but strong young healthy won't die from it, but grandma will. Best to self-infect and quarantine so you don't accidentily infect grandma. It's the civil thing to do.
The probability of dying is much lower when you're young and without obvious preconditions, but there are twenty year old patients dying that seemed perfectly healthy.
Yes but it's still a significant risk, would you not say? The coronavirus outbreak itself could be described as an outlier event, should we discount it?
No, it's not a "significant risk". It's basically the flu to the young. The IFR for that age range in good health is basically in the ballpark of the flu, which is a rounding error.
> No, it's not a "significant risk". It's basically the flu to the young.
Normally being wrong on the internet is just ignorable, this isn't. At its best, this is 10x more deadly that the flu (more so for young people because almost no one dies of flu while young). You can dismiss that if you like, most people are right to not.
I’d do it. Everyone is going to catch this. I think I already had it (doesn’t everyone?) but in the event I didn’t, if I could volunteer to get infected I would do it.
I’m assuming because you are sure having it once will give you some immunity? It’s really unclear if that is true and I respectfully disagree with those who same it is more likely than not.
Stop spreading misinformation, there were studies in South Korea that say you won't reinfect after you get it. That's why the strong and healthy can help by self-infecting.
Not exactly.
Some hundreds of patients were thought to have gotten rid of the virus during hospital stay and treatment and sent home after confirming through RT-PCR tests. But they were found to be covid+ve afterwards. Studies indicated that the +ve tests were 'likely' from the genetic material that lingered from the first infection and not from re-infection.
https://www.livescience.com/coronavirus-reinfections-were-fa...
However, they do not declare that you cannot get re-infected two months down the line or two years down the line. We don't have that information about immunity yet.
"The great bulk of evidence' in this situation would mean the data on the duration of presence of Neutralizing antibodies in the blood stream of people who got rid of the virus.
But this data is not there yet,as I said before.
Scientists are currently working to figure out how long the antibodies stay in the body and if they are potent enough to fight re-infections.
There is 'no great bulk of evidence' yet. Unless I'm wrong, and I hope I am.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
"For any country contemplating these issues, another crucial question is how solid is the assumption that antibodies to SARS-CoV-2 spike protein equate to functional protection?Furthermore, if presence of these antibodies is protective, how can it be decided what proportion of the population requires these antibodies to mitigate subsequent waves of cases of COVID-19?"
"Furthermore, studies in COVID-19 show that 10–20% of symptomatically infected people have little or no detectable antibody."
We need more data, which I understand scientists all over the world are working relentlessly to deliver, to believe that 'you won't reinfect once you get it'
Most antibodies to viruses don't last forever, the question is not if you can get COVID19 twice (you almost surely can) but how long in-between are you protected.
And the evidence is unclear, and in some cases worrying:
As @tpnCC and @seppin said, there is significant clinical & scientific uncertainty about covid19 antibody response and duration, partly because there hasn't been enough time to collect the relevant data (for covid19) and partly because of prior resarch indicating reduced human antibody response to SARS.
Lower in this thread I commented about a 2011 resarch paper that demonstrated anti-SARS antibody levels fell by half 2 years postinfection and were undetectable 6 years postinfection in 21 of 23 SARS patients tested.
If those SARS numbers are in the same vein as what is true for COVID19, the only answer is a vaccine. Otherwise our current state of affairs is the new normal for the foreseeable future.
In that case COVID19 will play out like the 1918 flu, it will hit in waves that only mass quarantine will help mitigate, until enough immunity is reached. Likely 18 months - 2 years.
It's estimated that ~14% of common cold cases are caused by coronaviruses (HCoV-OC43, HCoV-229E, HCoV-NL63)... so although it seems particularly difficult, if we do manage to discover how to develop effective vaccines against Covid19, perhaps the silver lining is that vaccines against the related viruses responsible for a significant fraction of the common cold will be in reach.
There is a big problem with optimistically assuming immune systems will respond like SARS even, because we know in general terms the more severe the symptoms the longer the immunity lasts, but wait ... huge huge numbers of people with Covid-19 are asymptotic, that is not the cases with it’s SARS and MERS relatives! wake up people, herd immunity is delusional and dangerous. more likely is very short immunity, just like the other 4 Corona family virus which cause many of our common colds, high asymptotic rates, and reinfect us very very frequently and NOT due to mutations!
Just to spell it out: herd immunity depends on sustained immunity postinfection. It seems possible, perhaps probable, that covid19 "immunity" may have an unusually short duration or attenuated response, resulting in an effective herd population that is a fraction of the theoretical herd population. I.e. if 60% of Americans have been infected and recovered after 12 months, but antibody levels drop 25% after 12 months, the true number of immune americans comprising the herd will be less than 60%.
If so, we may need to consider pursuing a relatively slow and steady relaxation of lockdown to tune the rate of new infections such that herd immunity is kept as stable as possible - i.e. flatten curve into truly flat-but-nonzero line
We don't "know" that infection confers any sort of lasting immunity, but there's zero reason to believe it doesn't give you immunity at least for a few years.
This is all rooted in the media narrative trying to scare people to stay at home "you could catch it over and over again". It's not science, and it's counter productive.
Well, it's not science, but it may be productive. A lot of people will hear "it's not so bad" and "healthy people should get it and get over it", and go out and make others sick (including people that could die or be hospitalized).
It's not science, it's crowd control. People don't exercise good judgement reliably, so that might be counterproductive.
If people could deliberately infect yourself with a weak version of Covid19 , they would. Problem is strains are still somewhat poorly understood so its hard to understand who carries a tough strain vs weak one.
The issue with this approach is, it will not be possible to control the quantity or 'Infectious dose', which in the case of Covid19, may or may not affect how severely a person gets ill after infection.
My most recent treatment of ocrelizumab was ~$64k, which I have to get twice a year. It's not much more expensive than a lot of the other disease-modifying therapies for my condition.
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[ 6.2 ms ] story [ 136 ms ] thread> Monoclonal antibodies are lab-created proteins that resemble naturally occurring versions the body raises to fight off bacteria and viruses. Highly potent, they target exactly one site on a virus. In this case, the scientists used genetically modified mice to produce different antibodies to the spike proteins of coronaviruses. After a subsequent screening process, 47D11 emerged as showing neutralizing activity. Researchers then reformatted that antibody to create a fully human version, according to the paper.
I don't have any biology background - are you saying this targeting might not work?
Then there is the question of https://en.m.wikipedia.org/wiki/Antibody-dependent_enhanceme...
There are two such lock-and-keys on the antibody, the other key fits the immune system cells, that start a cascade that amplifies the immune response.
Even if it is a weak fit for an unintended target, the response can be an issue.
The biggest problem though, is cost. If you don’t have insurance, you may have to add a second mortgage to your house.
It might be more economically efficient (and convenient) for the strong and healthy to purposefully self-infect, and build up anti-bodies naturally. Herd immunity will eventually be built and corona will no longer be a problem.
I laugh when I hear people talking about a vaccine. We can’t get people to vaccinate for diseases like measles that spread faster, are deadlier, and kill kids.
Even in states with the worst coverage. It's closer to 90% in most of the country:
https://www.cdc.gov/vaccines/imz-managers/coverage/childvaxv...
So what are you laughing at?
There's not much question about getting there eventually. The path we take is the question.
You are apparently laughing that 10% of people will refuse a working vaccine and expose themselves to future risk? Fun.
As for the second:
>I laugh when I hear people talking about a vaccine. We can’t get people to vaccinate for diseases like measles that spread faster, are deadlier, and kill kids.
The relationship between immunity rate and effectiveness is not linear. It's be nice if we could vaccinate the anti-vax folks, but we don't actually need them to get massive gains from vaccinating part of the population. Rates as low as 70% would be incredibly helpful.
The reason why I doubt the end game is herd immunity via natural infection is:
* millions would die
* health systems would get crushed
* the virus is unlikely to disappear entirely, so would simmer around the world, triggering epidemics every few years or so.
What do you think?
But rebutting your individual points:
> millions would die
Unlikely. Improved estimates (thanks to serological data) for infection fatality rate range from 0.3% to 0.5%. If we can protect the most vulnerable populations, we can have a lower death rate than this-- e.g. in the under-30 crowd, the risk of hospitalization is 1 in 500 and the risk of death a tiny fraction of this (1 in 5000 or less).
Further, any variance of susceptibility or contact density means you don't need to reach 60% for herd immunity. Some estimates say that the real threshold may likely be 25% or less: e.g. https://www.medrxiv.org/content/10.1101/2020.04.27.20081893v... Further, lighter weight social distancing measures can further reduce Rt and attain herd immunity at a lower percentage.
If you assume we need 40%, and 0.25% IFR from protecting the most vulnerable-- you come up with 328k deaths. This is bad, but less bad than many alternatives. Note that the shorter lived the controls protecting the elderly and other vulnerable people, the more effectively we can protect them, too.
> health systems would get crushed
We'd not want to do what New York did, but let's look at it as an example. New York's health care system (barely) sustained the load. Now they're very possibly most of the way to herd immunity in NYC. Yes, we'd like to flatten the curve a bit from this and be better prepared.
> the virus is unlikely to disappear entirely, so would simmer around the world, triggering epidemics every few years or so.
The long term immunity question is interesting. Of course, vaccines could help improve this picture even if one ends up with disease-spread based herd immunity.
My personal belief is that A) total antibody-based immunity will last a few years, based on our experience with SARS-CoV-1; B) partial antibody-based immunity will likely last longer than that; C) memory B cell / T cell based immunity is likely lifelong and makes any subsequent course of disease less severe.
That is, I think it's likely that the current human coronaviruses that cause the common cold might very well cause a high death rate and be very transmissable if exposed to an immunologically naive population.
Of course, your third point holds even more true when it comes to interim suppression and containment efforts while we isolate and wait for a vaccine. It's an even more intractable issue to try and maintain suppression when the vast majority of the population is still susceptible.
This seems optimistic. I did the math last week, and 0.2% of New York City had died either from the coronavirus, or from something that was probably the coronavirus. About 21% percent of New York City was testing positive for antibodies. (Both deaths and antibodies are lagging indicators of infection, although a noticeable fraction of the deaths lag by quite a bit.)
That would give us an IFR around 1%. If we needed to have two-thirds of Americans catch the virus to reach herd immunity, that would be about 2 million dead. With any luck, some people are already immune. And as you point out, variation in susceptibility may stop things earlier than that.
The are some nasty side-effects in some percentage of survivors: Impaired breathing and damage from blood clots seem to be two of the most frequently mentioned, and Wuhan is apparently seeing a spike in dialysis patients.
The CDC is predicting 3,000 deaths/day in the US by June 1st. This seems plausible: We'd only need a few other metro areas to have a NYC-style spike.
So far, several countries do seem to be able to control the virus. But at this point, I increasingly fear that the US will not be able to do the same. We don't seem to be able to ramp up testing, and we haven't gotten the infection rate down to the point where contact tracing would work. And significant portions of the US seem to be giving up on control and going for a herd immunity strategy.
From samples returned 10 days ago, so add a bit more lag.
It's not beyond the realm of possibility that New York City has reached the herd immunity threshold. The biggest estimates of variance in contact networks and susceptibility (from fitting to case count data) predict a herd immunity threshold of ~15%. (Cited above).
> We don't seem to be able to ramp up testing
Testing, shmesting. It only provides a minimal adjustment to Rt; sensitivity isn't great, and you can't test everyone every day.
> we haven't gotten the infection rate down to the point where contact tracing would work
Nor will we. The most aggressive lockdowns produce case count decays of 40% or so per week-- possibly less. The suggested threshold for where contact tracing can work well is 1 infection per million population. The SF Bay Area probably has about 3500x that. -ln(3500)/ln(0.6) =~ 16 weeks.
IHME was predicting the virus would magically go away in California with continued shelter in place in the next 3 weeks. They just backed away from this crazy prediction that the data has never fit. However, policymakers depended upon it in making the tradeoff: aggressive policies aimed at control could be justified if they'd really get us to a sustainable containment regime in a couple months.
> And significant portions of the US seem to be giving up on control and going for a herd immunity strategy.
In the end, the only long term paths are to radically change our way of life forever, or herd immunity. There's only really one vaccine effort that could deliver tens of millions of doses to North America by mid-2021, and that's the Johnson & Johnson program. Odds of that program's success are 50-50 at best.
"Something PROBABLY was the coronavirus?". So you're from the camp of "someone was shot 9 times, so he died from corona virus". I question the way you calculate the numbers.
It's also most likely still an undercount. Confirmed plus probable cases are thousands short of total excess deaths for that period for New York City.
(Prolonging the epidemic increases the number of people who will die this way, too).
I worded my statement intentionally.
> It's also most likely still an undercount
Some of the excess deaths will be other things. It will take more careful analysis to come up with reasonable breakdowns, and what percentage is likely covid-19 deaths.
Basically, as this article mentions - https://www.washingtonpost.com/investigations/2020/05/02/exc...
> “I think people need to be aware that the data they’re seeing on deaths is very incomplete,” said Dan Weinberger, a Yale professor of epidemiology who led the analysis for The Post.
> Those excess deaths — the number beyond what would normally be expected for that time of year — are not necessarily attributable directly to covid-19, the disease caused by the coronavirus. They could include people with unrelated maladies who avoided hospitals for fear of being exposed or who couldn’t get the care they needed from overwhelmed health systems, as well as some number of deaths that are part of the ordinary variation in the death rate. The number is affected by increases or decreases in other categories of deaths, such as traffic fatalities and homicides.
> But excess deaths are a starting point for scientists to assess the overall impact of the pandemic.
Specifically, I counted COVID-19 "confirmed deaths" plus "probable deaths" from https://www1.nyc.gov/site/doh/covid/covid-19-data.page. The probable deaths are defined as:
> People who did not have a positive COVID-19 laboratory test, but their death certificate lists as the cause of death "COVID-19" or an equivalent.
Since tests are scarce, they're not necessarily being used to confirm people who died at home or who died during triage. But COVID-19 is pretty distinctive, and in any case, the COVID-19 deaths are only a portion of the excess mortality.
Yes, as the Google article points out, the study is probably an undercount. IIRC, the samples were taken from mid-day grocery shoppers. If so, this would push the real NYC IFR higher, possibly into the 2% range. And as the Diamond Princess has shown, the real IFR continues to climb for weeks, as the final ICU patients succumb.
This would make the ultimate costs of herd immunity higher.
Not surprisingly, that paper has had some discussion: https://twitter.com/CT_Bergstrom/status/1257452758376091648
> It is true that if you could somehow pick and choose who became immune — the way you can in principle with vaccination — you might be able to do pretty well, vaccinating the high-contact individuals only and reaching herd immunity at low levels of vaccination.
> But natural infections don't spread like this. High-contact individuals are connected to low contact individuals. An epidemic spreads organically through the population, infecting who it happens to, not who you want it to.
> IF high contact individuals were only connected to other high contact individuals with high probability, you still might make some headway with nature disease progression. This sort of thing can matter for STD transmission.
> Respiratory viruses tend to be different. You have household transmission, cohort-based (school/work) transmission, and incidental transmission (subway/supermarket). These render the transmission network quite well-connected.
Additionally, if we're talking natural infection to get to herd immunity, you have the issue of overshoot, so unless you're very precise on measures to tamp down on transmission before you get to herd immunity levels, you easily overshoot the herd immunity threshold by quite a bit.
Surely high contact people are infected -more-, though, no?
In many ways, R0 is a "somewhat worst case number", in that it's something you observe in a population where the virus propagates well. There are likely to be other populations that it doesn't spread quite so well in-- either because of innate susceptibility or behavior differences.
> Additionally, if we're talking natural infection to get to herd immunity, you have the issue of overshoot, so unless you're very precise on measures to tamp down on transmission before you get to herd immunity levels, you easily overshoot the herd immunity threshold by quite a bit.
Exponential processes with a lot of delay and noise are a difficult controls problem, but it wouldn't be hard for jurisdictions that are doing well to target Rt=~ 0.95 .. 1.1 with interventions instead of trying to maintain Rt =~ 0.8. Of course, you need to be prepared to react quickly if things look like they are getting out of hand. And, thankfully, as the susceptible population drops the control problem gets a lot easier, because there's a ceiling of how high Rt can get...
"Six years postinfection, specific IgG Ab to SARS-CoV became undetectable in 21 of the 23 former patients. No SARS-CoV Ag-specific memory B cell response was detected in either 23 former SARS patients or 22 close contacts of SARS patients."
here is HTML version of article https://www.jimmunol.org/content/186/12/7264.long (DOI 10.4049/jimmunol.0903490)
The antibodies described here need to be tested en vivo (monkeys perhaps) to make sure they don’t actually lead to worse pathology (which for hCov-2019 seems to be immune mediated rather than directly caused by virus)
See my Twitter feed for references, I’ve been tweeting an immuno lit review (@100ideas).
here are my highlights of the article and other articles I cited https://twitter.com/100ideas/status/1255671725112659969
I could see a future where, like the flu vaccine, everyone is encouraged to get a SARS COV2 vaccine and there will be reasonable compliance.
Hospital systems were only really crushed in there places, Lombardi, NYC, and Spain. Only in Lombardi Italy did hospitals actually run out of beds (go over capacity). Even in London today the hospitals are under capacity. I am not saying this is a good yard stick to go by, I am pointing out that outside of three locations most hospitals are sitting virtually empty. Therefore it is unlikely health systems would be crushed.
As far as millions would die, again I would say look to the mortality rates outside of the three outlier areas (Lombardi, Spain, and NYC) and the mortality is far below 1%. I can see a future where COVID kills as many people as the flu. I don't see a future with a crushing mortality rate.
Viruses rarely disappear entirely, but the mortality rate is not high enough to be so afraid of it. It spreads fast, but not as fast as measles, whooping cough, or TB, which spread faster, kill more people, and also kill children. We try to eradicate those diseases for a reason. Covid is nowhere near their level. If we set the bar this low, we will be stopping the world economy every decade to fight viruses that bubble up and kill comparatively few people.
The infection fatality rate of someone in there 20's or even a teenager is basically a rounding error. The strong and healthy dying are the exception, not the rule.
https://pubs.rsna.org/doi/10.1148/ryct.2020200110
Plenty of comments implying that we're "all going to get it", which may be pretty much true in some areas in the US and Europe. I'm still holding out hope that being in Australia we may get a handle on it (although we just saw a huge cluster in a meatpacking plant). It's interesting to think that we might be heading for a world where some countries have had 60% prevalence and others have had 0.6% prevalence - what does that do for travel, trade, migration, tourism - all that stuff?
Before you downvote me, think about all the reports of people with VERY low oxygen saturation that "shouldn't be" alert, talking, and feeling ok. That goes against everything we "know" as well, but it's very real for this disease.
No one ever wants to be drafted, but sometimes an enemy larger than our personal preferences emerges.
We all live at this crossroads of time having, essentially, zero input into now. Now demands sacrifice. So it goes.
self-infect and self-quarantine, so you won't accidentally spread it to the immune repressed or grandma or whatever. Not only is this not "unconsciounable", I think the opposite. I have great respect for people who put themselves out of their way to protect other, less fortunate people.
That all being said, if theories of initial viral loads making a difference are true, it's not that crazy to imagine individuals choosing to self infect with a very small initial viral load so they can just stop needing to tip toe around life with the concern that they infect others, while continuing to isolate on their own. If I lived alone I'd be tempted.
Plus, we have no idea what happens to the infected a few years or a decade from now. If given the choice, not getting sick at all is the best possible outcome.
Only in the US :|
Ok, I'm willing to consider devil's argument, but this is just plain ridiculuous. The great bulk of infected people classsify this as "mild". If you're young, strong, and healthy, your chances of dying from this are basically zero in any common sense way. And far more people are going to "get bankrupt on the way to work" as you say using the current method. We're not trying to find a perfect solution, we are trying to find the better one.
There are zero longitudinal studies about the long-term effects of infection. For all we know, young healthy people could appear to beat the virus, only for it to hide out and plague you with severe health problems down the road. We could have an massive epidemic of a neurodegenerative disease caused by Covid-19 twenty years from now.
I have no desire to roll the dice on that even if the odds look good for me at the moment.
[1] https://epmonthly.com/article/neuropsych-complications-flu-v...
This is hardly a conspiracy theory.
[1] https://www.buzzfeednews.com/article/salvadorhernandez/coron...
https://www.npr.org/sections/goatsandsoda/2020/03/13/8146910...
> In 80% of known cases, COVID-19 causes mild to moderate illness, according to a report of a joint World Health Organization-China mission of 25 infectious disease experts held in China late last month.
> At a press conference on March 9, Maria Van Kerkhove, technical lead of the WHO Health Emergencies Program, said: "[A] mild infection starts normally with a fever, although it may take a couple of days to get a fever. You will have some respiratory symptoms; you have some aches and pains. You'll have a dry cough. This is what the majority of individuals will have."
> It is "nothing that will make you feel like you need to run to a hospital," says Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security.
> A mild case of COVID-19 in and of itself is not dangerous.
Take a look at the forecasts of hospital bed utilization if 20, 40, 60% of the population were to be infected over a 6, 12, or 18 month period: https://projects.propublica.org/graphics/covid-hospitals
Anywhere on those maps that show red indicates people dying due to hospital resource exhaustion, either from COVID-19 or unrelated health issues. To a lesser degree this is happening in yellow areas as well.
And ProPublica is only considering beds! Medical personnel, supplies and equipment are finite resources as well. Personnel cannot handle 18 months of 200% bed utilization, and they don't have the PPE they need as it is.
There is no easy fix to this situation; we are facing the kind of problem that is best met with thorough preparation, but unfortunately we don't have that.
The government can print money, and implement programs to distribute food and other necessities. They can't print tests or masks or vaccines -- once the resources are put in place, it simply takes time. Realistically, it will be a long time before even one of those three things is in a good place. Probably not this year.
A more achievable goal than herd immunity is to find a workable way to reduce the number of viral carriers and limit transmission while we wait for the tests, masks and vaccines that we need to get society back on track. That requires leadership and coordination, but it especially requires us to accept the seriousness of the situation and behave responsibly.
If New York has "survived" this wave tolerably and 20% of people are immune, they may well be a quarter of the way to herd immunity. Which is still a lot of suffering to go, but it's also not going to take 18 months of 200% hospital bed utilization either.
2) New York City has lost .2% of their entire population to get to that ~20% number. Extrapolated out, that's once again back to the 1-2 million deaths range for the country to hit herd immunity.
My guess is that it will be the same thing like swine flu 10 years ago. The media will print out a sensationalized number, and the real numbers will end up being 10x fewer when calculated honestly.
It's been 7 weeks since the Imperial College model that predicted up to 2.2 million deaths in the US, that used an infection fatality rate of 0.9% as an assumption. The best science still has us in the 0.5% to 1% range for IFR, still putting us in the 1-2 million range if let ourselves get to herd immunity levels without a vaccine.
I think we'll avoid getting to 1-2 million, but it'll be because we take actions along the way to push some/most infections to post-vaccine or post-effective treatments.
> Try to reach it without a vaccine, and millions will die.
https://www.nytimes.com/2020/05/01/opinion/sunday/coronaviru...
And of course we will get herd immunity soon, with the way exponentials work. We are re-opening the economy! We will reach herd immunity far quicker than we will get a vaccine.
What a well reasoned rebuttal.
If someone told me I should deliberately catch a cold I'd say no. What about Ebola? I'd say no! A germ that I don't know? I'd say no!
If a police patrol arrived somewhere and someone ran away, that person would be suspicious. If I'm asked to get any germ I'd suspect that it's very dangerous, even if it was just a cold.
So telling people to infect themselves deliberately won't work.
The probability of dying is much lower when you're young and without obvious preconditions, but there are twenty year old patients dying that seemed perfectly healthy.
We simply do not know yet whether it is a good idea to infect everyone.
Why is everyone here a medical expert?
Normally being wrong on the internet is just ignorable, this isn't. At its best, this is 10x more deadly that the flu (more so for young people because almost no one dies of flu while young). You can dismiss that if you like, most people are right to not.
https://www.independent.co.uk/news/health/coronavirus-younge...
https://www.bbc.com/news/health-52003804
Scientists are currently working to figure out how long the antibodies stay in the body and if they are potent enough to fight re-infections.
There is 'no great bulk of evidence' yet. Unless I'm wrong, and I hope I am.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6... "For any country contemplating these issues, another crucial question is how solid is the assumption that antibodies to SARS-CoV-2 spike protein equate to functional protection?Furthermore, if presence of these antibodies is protective, how can it be decided what proportion of the population requires these antibodies to mitigate subsequent waves of cases of COVID-19?"
"Furthermore, studies in COVID-19 show that 10–20% of symptomatically infected people have little or no detectable antibody."
We need more data, which I understand scientists all over the world are working relentlessly to deliver, to believe that 'you won't reinfect once you get it'
And the evidence is unclear, and in some cases worrying:
https://www.independent.co.uk/news/world/asia/coronavirus-ja...
Lower in this thread I commented about a 2011 resarch paper that demonstrated anti-SARS antibody levels fell by half 2 years postinfection and were undetectable 6 years postinfection in 21 of 23 SARS patients tested.
see this chart https://www.jimmunol.org/content/186/12/7264.long#sec-7
https://en.wikipedia.org/wiki/Human_coronavirus_OC43
http://www.columbia.edu/~jls106/galanti_shaman_ms_supp.pdf
If so, we may need to consider pursuing a relatively slow and steady relaxation of lockdown to tune the rate of new infections such that herd immunity is kept as stable as possible - i.e. flatten curve into truly flat-but-nonzero line
This is all rooted in the media narrative trying to scare people to stay at home "you could catch it over and over again". It's not science, and it's counter productive.
It's not science, it's crowd control. People don't exercise good judgement reliably, so that might be counterproductive.
http://www.columbia.edu/~jls106/galanti_shaman_ms_supp.pdf
There is documented cases where people in the middle ages would deliberately take small doses of poison to develop inmunity to poison itself.
https://en.m.wikipedia.org/wiki/Hormesis
If people could deliberately infect yourself with a weak version of Covid19 , they would. Problem is strains are still somewhat poorly understood so its hard to understand who carries a tough strain vs weak one.
We had a discussion on sending everyone under 30 to a giant Coachella for a month. I'd be so down.
https://www.newscientist.com/article/2238819-does-a-high-vir...
For example: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570079/
Also, how much of the high cost is research cost, and how much of that is per-unit production cost?