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AstraZeneca Scientist Says Delta Variant Makes Herd Immunity Impossible (businessinsider.com)
84 points by lnyan on Aug 13, 2021 | hide | past | favorite | 176 comments


Wont we achieve herd immunity via natural infecion then? Unless the virus starts to become like flu, which evades the the natural immunty very easily.


if the problem is that the immune response drops too low to prevent infection then there may be no herd immunity from that either, it can just cycle around.


With highly contagious diseases, herd immunity is kind of a meaningless concept. Eventually close to 100% of people get infected.


What is the nature of the delta mutations ie what mechanism/a make it more infectious?


I read this article, it sheds some light on this:

https://www.pbs.org/newshour/health/how-these-mutations-made...


The measured viral load is substantially higher (e.g., 1000x in some studies) vs the original strain, and it is suspected, but not proven (afaik) that this translates to more exhaled virus.

What is known is that the virus ramps up in the infected people more quickly, and stays infectious longer, so for sure, each person is infectious for more days on both sides, increasing infectious opportunities.

In the vaccinated population with breakthru Delta cases, the viral load initially approaches the load of unvaxed people in the first few days after becoming detectable, but then falls off much more rapidly.


The original 1000x study (I don't know if there's been another with a number that high) was actually a measurement of viral load on first detection. This is different from straight up viral load (other papers seem to indicate that delta is more like 4x viral load at peak compared to alpha at peak). The 1000x is due to how aggressively delta variant is about to replicate.

As for what the actual changes in mechanism is... I could try to summarize this (https://www.nature.com/articles/d41586-021-02039-y), but I think I would fail. It's a nature news article (so free access for everyone!). It's on the technical side of pop-sci.


Can people who had the OG Covid(me) get it and get sick again? or are they more or less okay?


There are only handful of verified cases of people getting covid more than once. It's extremely rare from what I can tell.


Both are fairly rare, but the latest data I've seen shows both 1) weaker and faster decaying immune response in previously infected people vs immune response from vaccine, and 2) previously infected people getting infected at abt 2X the rate of fully vaccinated people. (Sorry, no ref links on hand at the moment)


Please post those links later when you get a chance


Here's a few:

Johjns Hopkins: Why COVID-19 Vaccines Offer Better Protection Than Infection https://www.jhsph.edu/covid-19/articles/why-covid-19-vaccine...

NIH: How Immunity Generated from COVID-19 Vaccines Differs from an Infection https://directorsblog.nih.gov/2021/06/22/how-immunity-genera...

Also, preprint on kinetics of regular infections vs breakthrus, showing vaccines rapidly suppressing viral loads - "Virological and serological kinetics of SARS-CoV-2 Delta variant vaccine-1 breakthrough infections: a multi-center cohort study" https://www.medrxiv.org/content/10.1101/2021.07.28.21261295v...

Most illustrative is the chart on ~pg16, line 298.


I wonder how Covid compares to the bubonic plague. It remains endemic in some parts of Asia (so not disappeared), it is zoonotic (rodents, even cute squirrels in some parts of the US), killed off something like 1/3rd of Europe’s population, and... is generally a non-event nowadays.

Not a pretty comparison if valid, of course. But that was what would be a nightmare scenario for Covid: letting the disease rip through a populous continent. And yet it burnt out eventually, over the course of 7 years, according to Wikipedia.

For the most part, anyway. Bubonic plague outbreaks continued for centuries, but never again was there a continent-wide pandemic.


Is this a trap question? I mean you can make 2 cases.

Firstly the noncontroversial part: covid is a virus, bubonic plague is a bacterium. In the covid case, infected people infect others. Stay away from people, especially in restaurants (so, probably, eating near an infected person is a strong vector), and there isn't much chance of infection. In the case of bubonic plague: enter a building where an infected person had a shit 2 months before ... there's a decent chance you get infected. It's a world of difference. Objects are safe, with covid. Streets are safe. Beds are safe. Public toilets are safe. Public toilets would be a death trap with the bubonic plague.

You ignore age? They're comparable in death rate.

You only count people under 40 (life expectancy, without bubonic plague, was only about 30-40 years when bubonic plague got it's big moment). So if you compare that to what covid does to people <40, it's much less than the mildest flu ...

Let's say you relax that by a lot and say, no people live to 70 in the 14th century, about double the real figure ... covid is about an average flu.

So ... like everything, it depends. If you make a case based on years lost, covid is an exceptionally deadly flu, but less than 1% as bad as the bubonic plague.

If you make a better comparison, and compare Covid to Tuberculosis, today, then for the first 4 months it got to about half as bad as TBC, then fell off a cliff. If you take an average over a year, TBC wins on all fronts: people infected, people killed, years of life destroyed, ... well, except on dollars spent.

BUT covid kills many rich old people in the west. Tuberculosis kills young poor adults, mostly in the third world. Tuberculosis produces orphans. Not that I don't think rich people in the west they have right to a few more years, they very much do. But you want to help humanity, it's the wrong target.

So Covid only really wins from even contemporary diseases in the "dollars resisting the deaths" department.


Isn’t that partially because some people had better resistance to it and the survivors passed it on? https://www.studyfinds.org/bubonic-plague-human-immunity/


Maybe. This could happen with Covid too.

Not a pretty scenario! But better than deadly-remains-forever.


We had a chance to keep a new disease under control, but it's increasingly looking like humanity blew that chance. There was definitely political interference in the US, and other places, people prioritizing the success of their favorite politicians over fighting a common enemy, but I'm not sure if we would have succeeded in fighting this back even if the US and other nations with political interference had not had the traitorous attitudes.

Makes me realize how lucky we were with the first SARS and with MERS.


It’s not a US issue. The delta variant did not originate from the US. If we want to fix this we have to help other countries.


That's why my comment explicitly said "and other places." I agree that this needed to be a global effort to succeed, and in the past the US would have helped the cause rather than hindered the fight against the diseases. I am still absolutely shocked at the poor testing response of the CDC, both in 1) the huge lag before allowing testing by anyone, leading to the Univeristy of Washington discovering it against the wishes of regulators, and 2) completely botching the initial test manufacturing due to newbie mistakes. It was a failure mode that nobody even anticipated in planning, because it's so ridiculous that the CDCs capabilities fell so low.


I agree with your criticism but also firmly believe that once COVID started spreading beyond a few handfuls of individuals, its fate as a human endemic disease was locked in. No difference in policy by any or all countries would have changed that eventuality, other than at most modify the timeline slightly.


Agreed, all that a good cdc response does is t+n the endemic.


No, a good CDC response reduces the number of deaths along the way to endemic


Are you referring to people who died but wouldn’t have had the hospitals not been filled?


No... early social distancing would have dramatically reduced R0. It's exponential growth. Fewer infections => fewer mutations.

Proper masks (electrostatic or nano layer) are widely available, and they all but stop the original COVID. They cost a buck. The nano ones can be reused several times. Providing those prior to vaccines would have been cheap and effective.

Masks + vaccines + modest social distancing would have stopped it then. They would have been to rush to get vaccines to everyone, and to prioritize by exposures (e.g. service workers before WFH employees).

Plus, look at China. If we all did what China did, we'd be done.


You can only do what China does with an authoritarian government. And I'll take a virus over that any day of the week.


> and they all but stop the original COVID

Would love a citation on that. I think masks definitely help reduce transmission but they are hardly a magic bullet.

Anyway we can reduce R0 to zero in the short term and it wouldn't matter to my thesis. COVID circulates in animals so as soon as we would take our foot off of the brakes it would again start spreading in an unbounded fashion. And the world can't undergo a complete global lockdown while we wait years for vaccine availability. It's just impossible from any point of view: political, economic, social, etc.


The best source I've seen are the tracing studies in China. Police state meant China could follow exact paths -- from camera footage -- of who caught COVID from whom. If both sides wore surgical masks (imperfect fit, but electrostatic layer), there was almost never any spread.

Singapore hospitals were good case studies too. Hundreds of COVID19 exposures early in the pandemic, with virtually no spread.

You can do web searches for both.

Million dollar question is how this impacts delta. Delta has higher viral loads, and it's perfectly possible filtering 95% of delta will still result in more virus than the original, unmasked. Things also get more complex with both sides filtering; naive math would place filtration at 99.75% effective, but I don't believe naive math in this case beyond saying "a lot more effective."


I wish I could find the study, but back in December there was a study indicating that frontline medical workers working directly with COVID patients every day and wearing N95 masks were more likely to have been infected by social contact outside of work then at work. I remember the day because it's when I went and bought KN95 masks.


The simple fact is that unmasked, the mean amount of time you can spend face to face with an infected person (with pre-Delta COVID) before you get infected yourself is maybe an hour or two.

Many, many doctors and nurses were caring for COVID patients every day for 9 months before they were able to be vaccinated. Many spent hundreds-thousands of hours in contact with COVID patients and didn't get sick.

This is extremely strong evidence that N95s work.


I am upset with the CDC too but even if we were perfect from Jan 2020 through Aug 2020 (or whatever) we'd still be getting hit with delta now.

The US just ordered 200M booster shots. Making these is pretty much cutting into the capacity of other countries to get their first shots. I am for this - they are American companies and the US should happily pay for them for its citizens. But when there 7.5B other people in the world its not really up to us when the next variant hits.


The primary fuel for evolution of new variants is the spread of infection. Every time the virus copies itself is a chance for a new mutation, another roll of the roulette wheel for the creation of a stronger sARS-CoV-2.

So by letting infections spread as far as they did, we gave the raw evolutionary fuel to create new, more contagious, variants.

If we had cut the number of global infections in half, we might be living in a timeline where a delta-like variant never evolved.

We developed vaccines in record time, but if we had a way to distribute them more quickly, maybe it would have been prevented.

It's a global fight, and every government that let it get out of control worsened our chances at containment.


I mean the delta variant took a plane trip here. The US could’ve stopped that.


That would have only delayed arrival of the delta variant by a few weeks at most. The US has always had de facto open borders with no real effective security.


Delta and other variants are not unlikely events though: the expectation is that they would emerge independently anywhere that the virus is freely replicating.

Delta is so named because using "origin of identification" kept convincing people the virus came from there, rather then was first isolated in a lab - and that relatively straight forward mutations couldn't emerge in multiple places with widespread infection simultaneously.


The US was (and to a lesser extent still is) exporting harmful Covid-19 mis-information.

Your point about helping other countries to help all countries stands.


I think my country (France) and dr Raoult has its share of responsibility. Let’s not even talk about China’s responsibility in this mess.


Both US and EU countries kept vaccine production patents for profit effectively allowing the world to go unvaccinated and the mutations to go rampart. India a vaccine production behemoth but also others asked, begged but to deaf ears. Helping other countries looks like a US and EU issue.


Food for thought

> BioNTech alone could lift German economy by 0.5% this year

https://www.reuters.com/article/us-germany-economy-biontech-...


is the origin really known?


yes. genomic surveillance makes it possible to measure the presence of various strains in various areas and their ongoing mutations.


Yes. India.


India [0], and with > 1B people there, that's a whole lot of opportunities to mutate, and a whole lot of jabs to manufacture, distribute, and perform. In the case of mRNA vaccines, they need to be kept quite cold until basically day of use. India is poor and hot, it's non-trivial to say the least.

As others have said, this isn't primarily a US problem; 30.7% of the world population has received at least one dose of a COVID-19 vaccine, and 16% is fully vaccinated [1]. Even if 100% of the US population were vaccinated, it'd barely move those figures.

[0] https://www.thequint.com/coronavirus/covid-variants-found-in...

[1] https://ourworldindata.org/covid-vaccinations


Even if in the US we had achieved 100% immunization for the covered ages, there are parts of the world which are way behind and it would have happened there if not India, Brazil or the UK.

So it's a false proposition to say if we in the US had achieved 100% immunization it would have stopped any mutations. It would not have.


Yeah, but that's not a proposition that I've ever heard anyone state. I certainly didn't say that in my comment, the comment you are responding too.

It's a global effort, and we played the game with one of the strongest players suffering a concussion and a hangover.


My point is, unless we had achieved artificial "herd immunity" world wide, mutations would have occurred. Since it's quite clear we could not have achieved artificial "herd immunity" mutations were going to happen regardless of what we did in the countries who had the resources for full immunization of eligible population.

There was no realistic chance of keeping this under control once it spread beyond Wuhan.


> There was no realistic chance of keeping this under control once it spread beyond Wuhan.

This is probably our main point of disagreement then. Given that many governments did quickly get it under control, I would contend that with proper testing and quarantine during travel, it could have been extremely different.

There was a lack of global coordination, and with that coordination I think this could have turned out very differently. And I fear that we are not learning the lessons to prevent another incident precisely like this one.

That said, I'm not fatalistic, and think there still may be a chance for wiping out this disease, but I think it's only going to get harder with time.


Even with a high rate of vaccination it will unfortunately be impossible to eradicate SARS-CoV-2. Unlike smallpox or polio there are animal reservoirs. And while the vaccines are very effective at preventing deaths they don't really stop the spread. Any notion of wiping it out is simply wishful thinking not grounded in scientific reality.

The most likely scenario is that almost all of us will eventually be infected no matter what we do.


I mean, is there really any point in saying what would've or not have happened anymore other than some notion of nationalism?

I was at Newberry Lava River cave, Oregon last week. There was a mandatory orientation before entering the cave which went along these lines: "this cave is a bat sanctuary. As you may or may not know, Covid is a zoonotic disease that is transmissible between humans and bats. If our bats here get infected, Covid will become endemic to North America and will never go away. I've had Covid, and I was bedridden for 6 weeks and have scars on my lungs. I would not wish this disease on my worst enemy. PLEASE do not go in if you're sick and wear masks if you do." People were walking in without masks even after hearing that. Not a peep from the multiple park rangers, because freedom, I guess.

As a species, we're pretty much just asking to be wiped out by the next pandemic.


Yes, there is a point because, as the top level comment demonstrates, faulty root cause analysis is being used to advocate for ineffective or counterproductive policy.

Also, I have to admit that message you heard is strange. I don’t believe there is evidence that humans can transfer Covid to bats, plus, if the sanctuary believes that, why are they letting anyone through at all? I would expect the consequential threat wouldn’t register as many people already believe the disease is not going away. I’m not saying wearing masks is unimportant but the cave warnings are a good example of how melodramatic speculation can be counterproductive when coming from officials. We won’t make progress by asking for perfect behavior to stave off doom.


> if the sanctuary believes that, why are they letting anyone through at all?

Good question, especially considering that they did go on to say that if covid was found in this bat population, the cave would be closed off for human entry permanently. I didn't probe further but I suspect that policy might be based on what you said about evidence of human -> bat transmission.

Still, I do feel that closing it off seems like the prudent thing to do. It seems kinda myopic to have a policy to only close after the fact while knowing full well that Covid is zoonotic and mutations can in theory occur in a bat population on North American soil. At that point, last year's exercise of pointing fingers at Wuhan effectively becomes a historic unfunny joke because it's not like the US tests their wild bats every day and what can possibly go wrong w/ reactive policies... </shrug>

My overall point though is that even if we have perfect root cause analysis, people will still choose to ignore anything from informed recommendations to even appeals to emotion. As they say, it only takes one bad apple.


It's a little late for that. SARS-CoV-2 is already endemic worldwide in humans and several other animal species.


It was even more challenging than that as many other mammals contracted covid-19 as well. So even if you immunized 100% of all humans on Earth, there would still be variants emerging periodically.


I think this is where people are reminded that Delta started in India, not the USA.


just a consequence of globalization, even 20 years ago the world was much less connected and things didn't spread as fast. Doesn't help that the entire planet wasted at least a month trying to contain it when rumors of something emerged in at least December 2019. Corona was being downplayed until basically the 1st week of March 2020

seems like Covid is going to be endemic like the regular flu where each year they have to try and guess which strain to make vaccines for


Just like many times in history as technology advances, such as how we couldn't stop mice/rats from spreading into other countries with ships - well before the crossing of the Atlantic/Pacific oceans reconnecting the Americas to the rest of the world.

Now there could be some small population in bats in a rural area in Asia which had some virus with a random mutation and it will no longer be isolated to those areas.

We've ultimately benefited greatly from breaking down these transportation and economic barriers and there's no going back without a serious regression in a ton of other areas (unless you want to live in a 'hermit' kingdom like NK). So it's a new reality we have to learn to adapt too.


Globalization only accelerates the spread a little. Evidence indicates that the previous major coronavirus pandemic occurred with HCoV-OC43. Apparently it started in 1889 and spread worldwide within a couple years. Even prior to widespread globalization people did travel and it only takes one carrier to spread the disease.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7252012/


> We had a chance to keep a new disease under control, but it's increasingly looking like humanity blew that chance.

Vaccinating 8.5 billions of people in a very amount of time is clearly not a reasonable goal to begin with. Even without war, extreme poverty, lack of access and political chicaneries about the who and what.

Humanity's best minds have been trying for years to create a vaccine for coronaviruses that last without success. Now we've tried to do this in less than a year and we don't know the long term effects, therapeutic or otherwise; and if someone does please provide your time traveling machine to the nearest university at once.

So yeah, the virus will become endemic, variants will appear constantly. What we do now is not a decision the people in white coat or black robes can or should answer.


Like pfizer delaying the vaccine after the election ?


Delta’s rapid evolution and plausible defeat of the vaccine which was rolled out incredibly fast, on the back of unprecedented economic lockdowns implies to me we didn’t stand a chance absent a global totalitarian regime just imprisoning everyone in their homes for a year by force.


We probably would have been able to contain the wider spread of this virus had politicians shut down all non necessary air travel immediately after WHO/China officially declared a potential pandemic incoming in January 2020.

They are all culpable.

All but Jacinda Ardern, very smart government that one.

The need for speed:

“Three days after WHO declared the coronavirus outbreak a public health emergency of international concern on 30 January 2020, New Zealand began introducing disease prevention measures and continued strengthening them in the weeks that followed.”

https://www.who.int/westernpacific/news/feature-stories/deta...


No that wouldn't have allowed for containing the spread. All it takes is one carrier getting through from "necessary" air travel or illegal immigration or whatever and then the exponential spread starts in a new area. Thus uncontrolled spread was inevitable in most countries. The only exceptions are a few isolated places like New Zealand which can actually control all arrivals.


Fewer cases means tracking them is still feasible. Exponential growth can only happen after officials are overwhelmed with cases. Shutting down air travel probably would have relieved pressure enough to follow up on cases - doubling rate tells us beginning of February would still have bought us the necessary time. Beginning of March to mid of March it was game over already I agree.


Case tracking hasn't really been effective even in areas with limited spread. It's a failed strategy. Exponential growth starts immediately as soon as there's one contagious carrier, although it takes a couple weeks for absolute numbers to grow really large.


What about South Korea? Mask mandates? In addition to lockdowns. I mean it’s multiple things that politicians and officials had to get right of course. Unfortunately >90% really failed us on that practically everywhere.


South Korea has a growing number of cases.

https://www.worldometers.info/coronavirus/country/south-kore...

Mask mandates can be marginally useful in slowing down the spread on a temporary, limited basis. But they're obviously unsustainable. The virus is here to stay and asymptomatic people aren't going to wear masks forever. Much of the spread takes place inside private homes where no one wears masks.


I thought we were still talking about the beginning of the pandemic? South Korea did fend off the virus through contact tracing, mask mandates and lockdowns early on. Unfortunately most other countries did too little too late which was my original point.

The result being that by now we have a full blown ever-pandemic at hand - which includes South Korea by definition.


Why do you say "air travel" and not "international travel"? Before COVID got here, domestic air travel was perfectly safe, and a boat from China is just as capable of carrying COVID as a plane from China is.


I agree especially in dense places like Europe (thinking of Italy outbreak) early border shutdown for non essential travelling would have helped in addition down the line. I’m not sure boat travel is comparable to air travel in both mass and interconnection around the globe. It would probably have also been warranted but main driver here was globalization / air travel.


... or using N95-equivalent masks and mild social distancing ...

What's scary is gamma through omega.


That’s assuming the characteristics of the virus were known upfront but they weren’t. The conflicting, even suppressed, information early on didn’t help.


which comes back to "politicians made it worse" - the CDC knew damn well that masks worked, that's why they wanted to reserve them for medical practitioners, and put out knowingly-false statements that the science indicated that masks didn't work.

https://www.usatoday.com/story/news/healthcare/2020/03/02/se...

https://www.businessinsider.com/fauci-mask-advice-was-becaus...

it's not any one thing but - if Trump had told people to be patriotic and wear their masks for america, and the CDC had just told people that yes masks work but we need the medical one for the doctors so make your own (which is what they ended up doing anyway), and Trump hadn't seized PPE supplies from doctors so that JKush could auction them off for a personal profit, etc etc - the outcome would have been significantly different.

but for Trump all that really mattered was "his numbers". He didn't even want to bring in a cruise ship full of dying people because that would make "his numbers" go up, even though it was already all over the west coast by that point. He knew damn well it was deadly, and that it was spreading everywhere, he told it a Pulitzer-winning journalist in as many words.

Like, shame on Fauci for playing into Trump's game, let that be a lesson on what happens if you let a politician compromise your medical ethics, but... Trump had a huge part in kneecapping the response. Literally everything he did was exactly identical to the actions you'd take if you were trying to increase the spread. Lie about the spread, lie about the severity of the symptoms ("just the flu"), lie about masks and make up fake treatments like Chloroquine and Ivermectin, literally stealing supplies out of the hands of first responders...

it's not hard to see that the response could have been a lot more effective without someone actively malicious at the helm. But it was hitting blue areas harder, and "those areas didn't vote for him" so he actively did everything he could to encourage the spread.

it's the "stealing the PPE out of the hands of first responders to let your son-in-law auction it" that gets me, personally. Like what kind of person let alone president would even think of that.


I remember listening to the virologists at TWiV in February 2020 talking about reports coming out of China (superspreading events, etc) and all of them pretty much were betting on the virus being airborne and aerosol transmissible back then already. All of them are US based scientists, lack of knowledge wasn’t the issue here indeed. It was really a total lack of preparation by officials so they had to keep those masks ready for at least some of the medical professionals.


I'd still like to see some solid evidence on exactly when the virus started spreading outside of China. Some estimates say it was in the US as early December 2019. I say that to mean timelines are very important if we're going to look back and do post-hoc analysis.

While I certainly don't mind the blame-all-the-US-politicians game, there are several points of failure. The CCP is most to blame because of the lack of disseminated information (that we now know they had) and attempts to suppress people communicating about it. The media largely ignored it for many of the same reasons that politicians did. Then the internet mobs, conspiracy theorists, and social media sites acting on behalf of political organizations didn't help either. It's death by 1000 paper cuts.


Yes I very much agree, it would be important to know more about the origins. Still the fact is that March was the time it really went “viral” with all the excess mortality and widespread health impacts. So we lost all of February - January even if you account early warnings from WHO. Cases probably doubled into critical exponential increments only in late February / early March meaning there was enough time for fast action (see New Zealand, beginning of February).

https://www.who.int/emergencies/disease-outbreak-news/item/2...

Definitely tons of mistakes were made from the get go but FWIW CCP regime went all in with their dictatorial measures after they couldn’t hide it anymore (January/February).

Though I mostly care about my personal perspective / “realm of action” being European / Canadian so EU and NA I hold up to way higher standards basically.

Pretty much all of the governments in these regions waved away the risks even though they had all the high-caliber scientists and some press warnings early on in addition to WHO’s warnings.

It goes without saying that the “leader of the free world” wasn’t paying attention didn’t help either.


There is evidence of the virus in Italy as early as September 2019.

https://journals.sagepub.com/doi/10.1177/0300891620974755


It would still spread in wildlife though, so it would have to be a forever prison.


SARS1 and MERS also lived in animals, but we were able to defeat those.

SARS2 is definitely a much more difficult foe, and counterfactuals are always hard to establish, but I think we came pretty close to fighting it back. And we might still!

I honestly have some hope for eventual elimination of the common cold (actually many different diseases, not one) to a large degree. Vaccine technology is advancing at a ridiculous pace these days. There is so much we don't know about immunology, but we are also learning so fast and biotech is accelerating too.


It's really not about politics, the vaccine simply didn't roll out fast enough to the entire population of the planet. What happened in the US is actually not that relevant as the US is only about 5% of the population of the planet, i.e. it's only 5% responsible for mutations, as the rate of mutations is proportional to the size of the susceptible population.

This is actually a "shortcoming" of tech. In quotes because the tech of the mRNA vaccines is actually stunning, but it just wasn't fast enough to test and manufacture (development was pretty much instant, the vaccines were ready in January 2020).


“ We had a chance to keep a new disease under control, but it's increasingly looking like humanity blew that chance.”

???

The article says vaccinated people spread the virus; if everyone wore N95s, wildlife could still be spreading COVID so it would come back once masks were off… (unless we discover a delta vaccine that we roll out to the world over the next N years while everyone isolates and that prevents vaccinated people from spreading)


Any chance to keep the disease under control was lost the moment a carrier got on an international flight on Wuhan. After that uncontrolled worldwide spread was inevitable. Those who think containment was possible are engaging in magical thinking and fail to understand the mathematics of exponential spread.


One only needs to look to other diseases (SARS, ebola) to show that your logic is not sound.


It might be a bit counterintuitive, but higher fatality rate (SARS, ebola) actually limits the virus' transmissivity, making them harder to spread.


Half of the U.S. refusing to get a vaccine was not inevitable.


That has nothing to do with the development of the Delta variant or it’s effect on the rest of the world.


And that would have suppressed variants emanating in India, Brazil, UK and South Africa how?


I disagree that there was single possible outcome to all of this, and that there's nothing we can do to slow the spread of the Delta variant, or give people a better chance at surviving this. I didn't spell all that out.

To be clear, if I could have shipped all of the (idiotically) unused vaccine doses in the U.S. to India, Kenya, etc., then I would, but I can't. Would that stop the Delta variant? Apparently no, but it would save lives.


As of last week the US had already exported 110M vaccine doses.

https://www.wsj.com/articles/u-s-says-it-has-shared-110-mill...

Unfortunately most of those unused vaccines require careful low temperature refrigeration. The necessary cold chains don't exist in most parts of India or Kenya.


So what's your takeaway, then? Should we have hoarded vaccine that people are refusing to take? Maybe someone could have made a quick call to Mumbai to see who had the right kind of freezers, I don't know.

The fact that the U.S. has hospitals full of unvaccinated covid patients, when you can walk into any Walgreens and get a vaccine in 15 minutes makes me insane.


Your complaints are disconnected from reality. Vaccines aren't being hoarded. It takes time to set up export and delivery cold chains with all of the necessary quality and safety checks. Giving people spoiled vaccines would be worse than no vaccines.


You could also make the argument that letting the initial variant of the virus run its course may have been wiser than society wide mandates that prolonged it. Given the low infection fatality rate, if everyone under 50 in the US caught it, we would have around 30,000 deaths (or same order of magnitude if my estimate is off) because the IFR for those under 50 is so incredibly low. Then the rest of society would be well protected as well and we would have a high natural immunity against new variants that developed. If enacted worldwide, perhaps the reduced transmission may have avoided the delta surge altogether. Note that the CDC’s projections show that a higher natural immunity would mean reducing cases for delta even with limited masking.

Also the first SARS was far less transmissible. Generally speaking as viruses mutate, they tradeoff R0 and severity. It is unlikely the first SARS would have evolved a variant that was more transmissible and equally fatal.

EDIT: Note that even though increased transmissions can mean more mutations leading to dangerous variants anyways, if the alpha variant were spreading broadly before something like delta was broadly spreading, then the delta variant would contend with a higher natural immunity in the global population, which would make it difficult for delta to take hold in the same way. The CDC’s own presentations show that even a limited increased natural immunity of 35% would mean that delta cases would reduce without new masking mandates or restrictions.


> Given the low infection fatality rate, if everyone under 50 in the US caught it, we would have around 30,000 deaths.

https://www.statista.com/statistics/1191568/reported-deaths-...

If everyone under 50 caught it, we'd have had way more than 30,000 deaths at this point because we've already had at least 30,000 deaths.

You also assume that Covid doesn't have serious long term complications arising from infections that are still being discovered. So you're basically suggesting that we yolo it during a pandemic and ignore the consequences of such.

Contrary to your myopic understanding of the topic... total exposure during a pandemic is actually not the way to manage it. 'the rest of society would be well protected' but instead we likely would have had a total collapse if everyone were to be infected at the same time by allowing the 'virus to 'run its course'.


Lets say that only 1% die. 20% needed high-end medical intervention to not die.

Once the infection rate hits a threshhold, the entire 20% die.


Your numbers are way off. The CDC estimates that since the start of the pandemic the hospitalization rate has been 5% and the fatality rate has been 0.6%. Of the hospitalized patients only a fraction needed high-end medical intervention such as mechanical ventilation.

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...

The hospitalization and fatality rates are far lower now for vaccinated people.


0.6% die, and some rather rubbery number end up with symptoms lasting from 6 weeks, or 6 months, or something. The rubbery number is sometimes quoted as 1/3 of people who enter hospital, which if 5% enter hospital would mean about 2% of the population die or are so incapacitated they can't work for some number of months. By comparison, just about everybody hospitalised for flu is fully recovered in 2 weeks. https://www.medicalnewstoday.com/articles/long-covid

2% is getting up there. Even if 75% avoid that fate by getting vaccinated, incapacitating 2% of the remainder will be enough to send us into a deep recession.


Source on your 20% number? That sounds really, really high.


For every person in the hospital due to covid is another person not able to receive care.

Hospital beds aren't unlimited.

ICU beds full? Someone has a heart attack? Well, sucks to be them.

That's the part of covid everyone is ignoring: it creates an additional burden on the health care system, hospitals that normally are booked solid for surgeries can no longer handle those cases due to the emergency influx from a pandemic spreading like wildfire.


Hospitals hit capacity and run out of beds and ventilators. This is a hard threshold. Once you pass it, mortality goes through the roof.


Running out of ventilators would have minimal impact on the mortality rate. Mechanical ventilation is currently only used as a last resort for <5% of hospitalized patients, and even with ventilators many of those patients don't survive.

https://www.cdc.gov/nchs/covid19/nhcs/intubation-ventilator-...

Beds can be added on a temporary basis. Availability of trained healthcare providers is the more relevant limit.


My point is even if hospitals were closed completely, it still seems unlikely that 20% of people who catch COVID would die from it.


No, that argument does not hold. The rate of mutation is proportional to the number of infected people. Every person infected over the course of the virus' spread is a single roll of the dice to see if a new variant arises. If X% of the population gets infected over the course of the virus, then you get the same number of mutations/variants regardless of the timeframe. Letting a disease spread rapidly just means that those variants all arise over a shorter period of time.

The way to decrease the number of variants that emerge over the course of a disease is by decreasing the total number of people infected over the full course of the disease. That requires widespread vaccination.


> if everyone under 50 in the US caught it, we would have around 30,000 deaths.

Personally, I value the lives of people over 50 just as much as those under 50. A lot of important people to me and to everyone is over 50.

Any non-sociopathic loss function would deem the half million people in the US that we've lost completely unacceptable.

And with even greater spread, there's greater likelihood of the rise of a variant that kills those under 50 just as much.

The only people proposing we should have let it run wild and also actually understand the consequences are absolute monsters that should be shunned and never given any authority or decision making power.


Since the vaccines don’t seem to stop transmission their only use is to protect the ones who take it. So there is no need anymore for vaccine passports and forcing people to take it.

Unless I’m missing something?


The do vastly lower the rate of transmission. That could translate into lower peak hospital utilization (even not accounting for their ability to prevent illness) which is good for everyone.

I do agree that this thing is going to spread in an unbounded manner regardless of what we do now though.


The vaccines don't stop transmission, but they still radically reduce it. Pfizer is 94% effective [1] in reducing transmissions of the original strain. Even with the delta variant it is still 64% effective:

[1] https://www.businessinsider.com.au/israel-may-reimpose-coron...


Total guess: Slows down transmission. Those that are asymptomatic should have a lower viral load, which results in fewer cases.


They don’t stop transmission but reduce its likelihood significantly. It seems someone who is vaccinated and very ill can be very infectious but generally vaccinated people are unlikely to infect others (reduced observed R0).


You may be misremembering the initial releases from last November. The goal of the first round of studies was to establish whether the vaccines were effective in protecting people who received the vaccine. The studies were not designed to determine whether it still spread, and so the statements were very precisely worded as "has not been verified to prevent transmission", or things to that effect.

Unfortunately, the English language doesn't make any distinction between "has not been observed" because it hadn't been studied yet, and "has not been observed" because it doesn't exist. Later studies have determined that vaccination greatly decreased the transmission, but by then the idea that they only protect the individual had taken root.


Vaccines definitely reduce transmission, just to a slightly smaller extent for the Delta variant. The CDC's messaging on this issue has been atrociously bad.


I can't open the article, it seems redirected to insider.com/asia


It seems they are confusing herd immunity with complete eradication? Most likely the virus will become endemic. We've already achieved a level of herd immunity.


But isn't vaccine supposed to make the virus less severe? I've seen many of my relative or friend of a friend who caught the virus weeks after getting the vaccine. Most of them have less severe effect, some of them still have critical condition..

At this point if even vaccine is not effective, then we're not sure how to kick this virus ass anymore

I'm still pro to get vaccine btw, I'm getting it once I am eligible :/


Many of the vaccines are effective against the delta, but they do not serve as a firewall to stop the spread of infection within a community.

As a simple example, imagine you have a community of 100 people. 1 person is infected, 98 are vaccinated, and 1 is uninfected and not vaccinated.

Ideally the 98 people who are vaccinated don’t contract the virus, and do not serve as vectors of spread for that one unvaccinated person. In essence, you make it so the one infected person has to come in contact with the unvaccinated person.

With delta, the 98 vaccinated people are astronomically less likely to die or become severely ill from covid; however, they still can contract and pass along the virus… Which can eventually make its way to the one unvaccinated person at the end of the chain.

So, vaccines are great. Vaccines work. These vaccines are awesome for how fast they were produced. But they aren’t able to serve as barriers of protection for the unvaccinated in a way other vaccines for other diseases.


Yes, the vaccines are still very effective against severe disease. It is transmissibility that's changed dramatically.


That is exactly what the article says (25x less likely to have a severe case/die).

The point is the transmissability (as also recently published by the CDC). You yourself get a milder case if you're vaccinated and catch Delta. But you can now still transmit it to children that can't be vaccinated (and who potentially are in a risk group), friends that have a contra-indication to vaccination but are in a risk group etc.


Shouldn’t there be a “with existing vaccines” be attached to that?

Delta was particularly infectious due to some mutations, but are those mutations antithetical in some way to antibody production? Why can’t b-cells just update their response and block that pathway with a new vaccine?

My understanding is this was always expected to be whack a mole with the virus anyway. All other endemic coronavirus reinfect people.


> but are those mutations antithetical in some way to antibody production?

The problem Delta presents to antibody-based protection is that there is a several day lag in the body's response to detecting the virus until it produces mass antibodies.

If the (small) number of circulating antibodies are overcome by a large viral load, and if the virus becomes transmissible in a shorter time period, it can "get inside the curve" of antibody response and result in a transmissible infection before the host mounts a full response. Delta is apparently a couple of days 'faster' than the previous Alpha strain in getting to the transmissible stage.


I see. So the issue isn’t so much a neutralizing antibody mismatch, but rather an antibody production lag in b cells.

That makes covid a long run big problem. We’ll have to be repeatedly challenged with the antigen to keep antibody levels high. Kind of a minor inconvenience for some, but a large % of the population will not comply.

Edit:

It would seem that it is basically speculation at this point. Memory b-cell response effectiveness will depend on the binding affinity of its antibodies. A high binding affinity antibody producing memory cell will much more rapidly mount an effective response than one that must undergo further affinity maturation.


The role of cellular immunity isn’t as clear. What would probably make a big difference, though, would be mucosal immunity given by a nasal vaccine. Get those antibodies located at the point of infection and they can get to work earlier.


I can’t read the article because of the pay wall. But the claims I’ve seen elsewhere basically say even with a perfect vaccine, you’d need something like 90% coverage to try and snuff out delta with vaccines alone because it is so incredibly contagious. So to a certain extent you can’t just fix the problem with a new vaccine.


To my understanding, that's correct. The R0 of the initial strain was somewhere around 2-3. For every infected individual, 2-3 additional individuals were infected. For the delta variant, R0 is around 8-9. In order to get herd immunity, `R0 * vaccination_rate * vaccine_effectiveness` must be less than 1. Even if a new vaccine can reach the same 95% rate as the original vaccine had on the original strain, the increase of R0 raises the necessary vaccination rate from ~65% to ~85%.

That's not to say that it's impossible. Chicken pox has a similar R0, but universal vaccination has greatly decreased the spread of the disease. At this point, it mainly occurs in small pockets of non-vaccination, and cannot spread significantly into the wider population. But that requires education and popular support, and is where we'll need to focus our efforts next.

[0] https://www.cnn.com/2021/07/29/politics/cdc-masks-covid-19-i...


We have 45% of Americans refusing to get a vaccine now, imagine the push back if we are attempting to get people to take a new one every 6 months. I don't have a better answer I just know that absolute chaos is down that road.


I don’t think it’s that bad. Remember that children < 12 still can’t get it, which is a good chunk of people.

Also, some people are not antivax, they are afraid of new mRNA technology. When the technology has had more time to bake, they will feel more comfortable.

Finally, Novavax will be coming online soon. That should help with some of the mRNA skeptics.


> Also, some people are not antivax, they are afraid of new mRNA technology.

then they can get the Janssen (aka Johnson & Johnson) vaccine which is not based on mRNA but an Adenovirus vector.


It’s viral vector which isn’t a traditional vaccine.

Viral vector has only been used before for Ebola. All US vaccines execute custom RNA code that was spliced from the real virus. Viral vector just gets that code in the cell by a different method.


Theoretically, though its far-and-away the most media maligned vaccine, and many clinics have ceased carrying it (I specifically have close contact with a few pharmacists who run rural CVS pharmacies; they sent their entire stock of J&J back, and regional has stopped sending more. its all mRNA).


Isn't heard immunity impossible anyway with current vaccines regardless of the strain, since vaccinated people can still carry and transmit the virus? Herd immunity only works if you have sterilizing vaccines.


Sterilizing or no herd immunity works if you can push R0 below 1. Below 1 fewer and fewer people get infection and the cycle stops.


Yeah but (current) vaccines are not stopping the transmission anyway, so they don't decrease R at all. That's been abundantly demonstrated already. (which is what Israel is finding out now after vaccinating almost everyone).


The vaccine does slow the rate of infection even Delta, but 59.9% is the current percentage of fully vaccinated in Israel and that's good but it's far from everyone. Very far given the infectiousness of Delta.


Vaccinated people are much less likely to carry the virus.


Not at all. They are much less likely to get severe symptoms, which is not at all the same thing. There are several studies already in several countries showing that with Delta the viral load between infected vaccinated people and unvaccinated people is identical.


Actually, herd immunity works if it reduces the R0 to less than 1.

Obviously, the extinction happens a lot faster wit a vaccine as you describe that reduces R0 to zero, but an exponential decline will still result in extinction (barring other reservoirs).


What's the R0 in a vaccinated population?


Are there scientific papers out there that are worth reading on the road ahead with what we know about the delta variant? I remember Neil Ferguson’s paper early 2020 that was a goldmine of information and predicted that we would have to do lockdowns on and off for a year and a half til the vaccine. It was pretty spot on.


It depends on what other measures they take. A big part of the problem is everyone said "We're vaccinated, so we're done." That put enormous evolutionary pressure for the virus to learn to hop the vaccine.


What about the intranasal vaccine?


That's what I want to know. A mucosal vaccine would be a very effective counter to the ramped up viral load and shorter incubation period that delta has brought.


As far as I can tell the conclusions we're going to have to draw are:

1) We need to keep using all strategies - including masking, social distancing, and targeted lockdowns - to reduce large scale spread of the virus. If we don't, we're going to be playing "new variant whack-a-mole" until the end of time.

2) Vaccination is critical to make the above task easier but it's not enough it itself. There seems to be a lot of evidence that it reduces chance of passing it on and the severity of the cases, but it's clearly not enough by itself (see Israel, although the remaining unvaccinated population is a big factor anywhere in passing COVID on).

We're also going to have to start kicking the asses of the pointlessly vaccine-skeptical through harsh restrictions and denial of things. In Australia, once we have universal access to the vaccine, I would be quite keen to see vaccine refusers not treated for free if they do get COVID - I'd support a "HECS"-like scheme for people who get avoidable diseases like this, including the government getting to sell your house when you die to recoup costs.

3) There's a pile of stuff we don't know about the long-term effects of COVID-19 and some ominous indications that it's Really Not Good. I don't want to get into a case-by-case with a bunch of self-appointed Internet Experts about this but there's a lot of medical opinion out there that long COVID is real and serious (particularly on the neurological side). We don't know how bad it really is because no-one has had COVID for more than 2 years.

Having participated in the care of multiple relatives over the years with dementia, one thing that chills me is the prospect that COVID will lead to even a slight uptick in the chance of getting Lewy body dementia or Parkinson's. That's a fucking public health tsunami.

We also don't know much about the effects of lockdown, etc. but the picture seems to be complex and indecisive. All the anti-lockdown people going on about suicides and depression apparently think the only source of suicide and depression in a massive pandemic where people are losing folks dear to them and are terrified of getting a debilitating disease is because they are locked down. As usual, it's the typical overreach of the Internet Expert.

Normal is a very long way off. The implications of COVID being 'endemic' certainly aren't what most people casually tossing the word around think they are, and magical thinking about 'living with the virus' isn't going to make long COVID go away.


And I suppose you yourself are not at all a self appoiunted internet expert with your broad and highly charged range of opinions without a single clear cut reference backing any of them up?

Worth noting as well is that you're trying to assert a negative without evidence-based substance as part of your particularly alarmist discourse. In effect: We don't know that COVID doesn't cause X list of aweful long term things I just mentioned, though no evidence so far indicates that it does, we should just assume it does however in order to push for a bunch of harsh and punitive measures against those with any skeptical take.


Actually, a good deal of evidence suggests it might. There have been 3 or 4 recent well-publicized studies suggesting neurological effects of COVID coming at various angles (imaging from Biobank, tests of various mental tasks on people who have or haven't had COVID, etc). The science is far from settled - sample sizes are small, effects are unclear, etc. This is fairly understandable as it's hard to tease apart correlation and causation, etc. unless you have before and after data (the Biobank study did, but the sample size is quite small).

https://www.medrxiv.org/content/10.1101/2021.06.11.21258690v...

https://www.thelancet.com/journals/eclinm/article/PIIS2589-5...

(a couple items I've seen recently)

The Parkinson's connection is explained here, although the tone, quite rightly, is very much "wait and see":

https://www.medicalnewstoday.com/articles/is-there-a-link-be...

UK science twitter is full of alarmed neurologists and epidemiologists yelling about this sort of thing. I don't work in the area, so maybe they're a bunch of clueless self appoiunted (sic) internet experts too. The idea that COVID does nasty stuff to the brain and might cause a small uptick in Parkinson's and Lewy body dementia also came from similar sources...

Here's the thing. There seem to be endless folks who, armed with a few slogans about "things being endemic" and a mock-realist take on things ("look at me, I'm the smart one who knows we have to live with this") are way more sure of themselves than actual doctors and scientists who study COVID patients and worry about long-term effects. I remember the Internet being full of self-appointed "just a flu" experts when COVID just got started.

I'd say that the prevailing tone among people who actually study this stuff is... caution. I agree. I'm not sure. You're the person who is apparently so full of certainty that we can just steam past all these worried experts (again).



It's too late to prevent large-scale spread of the virus. That already happened and it's now endemic worldwide. We don't have a time machine.

You obviously can't expect most people to continue tolerating masking, social distancing, and lockdowns indefinitely with no clear, achievable exit criteria. That would be absurd and people in free societies won't comply regardless of the potential consequences. You can complain that they're being irresponsible and putting others at risk but that won't change the reality.

At some point we'll have to accept the risk and move forward with normal life. Fortunately the vaccines are very effective at preventing deaths.


That's a straw-man. "Indefinitely with no clear, achievable exit criteria" isn't what I said.

A lot of countries have done masking as a default during flu season, without the massive chorus of whining from dipshits about it. Social distancing and lockdowns are obviously a bigger deal but this stuff could be targeted and less extreme than we've had to, pre-vaccine. The vaccine clearly reduces the severity of the spread even if it doesn't eliminate the possibility.

The word "endemic" is doing a lot of work in these kind of posts. It's quite compatible with absolutely ghastly public health outcomes, and frankly we don't know how bad it's going to get. You can spout cliches about "free societies" and "accepting the risk" and "moving forward with normal life" until you're blue in the face (maybe literally?) but maybe the normal life we're talking about down that path involves a order-of-magnitude increase in Parkinson's and Lewy body dementia.

I hope y'all enjoy changing diapers.


> 1) We need to keep using all strategies - including masking, social distancing, and targeted lockdowns - to reduce large scale spread of the virus. If we don't, we're going to be playing "new variant whack-a-mole" until the end of time.

How long do you think we need to keep using all strategies for? We've been doing that for almost a year and a half now, with no end in sight, despite having a vaccine available to everyone so quickly.


"We've been doing that for almost a year and a half" - have we? A lot of jurisdictions have done lockdown light, if anything. A few fitful weeks of half-measures, then declare that "lockdowns don't work" seems like the most common measure.

Right now we're suffering from the fact that the measures in Australia had stupid holes in them - we could be delta-free if the geniuses behind our quarantine policy hadn't had unmasked, unvaccinated limo drivers driving around air crew from other countries.


Here's my question. Current CFR for vaccinated individuals is under 0.05%. At that point does it matter if Covid's endemic?

I think the problem is we're all anchored to Covid from early 2020, which was definitely a huge danger. So we hear that there's still community spread, and fly into a panic shutting everything down. But at 0.05% CFR, it's barely more dangerous than seasonal flu. If Covid in February 2020 had 0.05% would we even have done anything about it?


Seasonal flu typically passes and has no lasting or permanent effects, in most cases.

What % of people get Covid and are noticeably operating at less than 100% thereafter? What % are operating at less than 70% thereafter?

Low CFR merely means you didn't die. It doesn't mean Covid didn't break you.


Long influenza absolutely does exist. At least to the same standard of self reported evidence that is being used to report long Covid.

[1]https://time.com/5915616/long-flu-1918-pandemic/


I've known multiple people that permanently lost their sense of taste after a bad flu.


Massachusetts is reporting 1% CFR for vaccinated individuals.

106/9,969, as of August 7th.

https://www.mass.gov/doc/daily-covid-19-vaccine-report-augus...


Take a look at this article, it explains why calculating CFR this way is not accurate:

https://www.capradio.org/articles/2021/05/10/no-the-death-ra...

    > Erin Mordecai, an assistant professor of biology at 
    Stanford University, agreed with Riley about the 
    miscalculation, and cautioned against the comparison. 

    > She said it’s impossible to accurately calculate a death 
    rate for each group — vaccinated versus vaccinated — 
    because demographics skew the data. 

    > “Those breakthrough cases may not be an average subset 
    of the population, they may be a more at risk group that's 
    more likely to have severe disease anyway,” Mordecai said. 
    “To better understand what's going on with the relative 
    risk, you would need to know the demographics of the 
    underlying health conditions of the people who experienced 
    those breakthrough cases and deaths.”


My comment is accurate. We are talking about CFR. Whether that is a key metric is a different discussion. I provided the numbers and the source.

P.S. That article did not age well.


You have misinterpreted the data. The CDC reports 0.6% fatality rate overall since the start of the pandemic. The fatality rate for vaccinated individuals is way lower, for all variants.

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...

Case fatality rates are completely meaningless and useless. The vast majority of infections never get officially tested or counted as cases.


I'm well calibrated on what CFR is, and I don't disagree that there are better measures. However, the parent made a comment about CFR, and so I updated them with more recent numbers, about CFR, which are 20x higher, so at the very least hints that perhaps their numbers are off.


You’re right. I screwed up by using CFR. Should have said IFR. Mea culpa.


Np! Lots of messiness in the data out there. I hope our data infra gets 8x-64x better in the years ahead. Maybe if we can get there this could be the last pandemic.


COVID IFR was always low. The CDC planning scenarios (https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scena...) consistently showed low IFR for those under 50 even mid 2020 in their earlier updates. However this was obfuscated by alarmist journalism and divisive politics, as well as people confusing CFR and IFR. COVID wasn’t that dangerous ever, unless you were immunocompromised or elderly, or unless your measure of danger is based on a high risk aversion.

There is the possibility of rare lingering side effects. However studies show that the worst side effects, like ARDS, primarily affect those who are obese or vitamin D deficient. You could make an argument that it’s the individual’s’ responsibility to manage their own risks and vulnerability for that. Alternatively you could say that those comorbidities are common enough that they require society wide management.


This doesn’t make sense. People who are infected by delta variant will become immune to delta variant. So if they are infected and it runs it’s course through the human population, people will get herd immunity from it. Or if we create a vaccine for delta variant similar thing should happen.

But we also already know that we don’t achieve sterilizing immunity from coronavirus even with previous infection or vaccine. So it was never the case that we couldn’t stop transmitting the disease.


> People who are infected by delta variant will become immune to delta variant

"people who were exposed to H1N1 flu last year will become immune to it, so once it runs its course people will get herd immunity from it and the virus will die out".

that's not how it works. What the scientist is saying here is that it's mutating fast enough that by the time we start to approach "herd immunity" (via vaccination or just exposure) it's mutated and the herd immunity is no longer effective against the new variant. So yeah you're immune to the strain from last year, but it doesn't do anything against this year's strain.

and on top of that Delta is literally so infectious that it'll just about spread right through the existing vaccines. The vaccines were 98% effective against the initial strain, now Pfizer/Moderna are 88% effective, which means you have 6x as much spread (at an epi/population level), on top of a strain that is, itself, 2.5x as transmissible. So now we have to hit a much higher level of vaccination (near-100%) to get the reproduction number under 1.0.

And then you've got the other vaccines - some early studies indicated Astra-Zeneca is only about 60% effective (!) which means even with 100% vaccination that vaccine could not stop the spread. Best-case scenario you have to get those people a booster shot of something else - and the clock is still ticking, it is still mutating and in another year the effectiveness of all the existing vaccines will be even lower.

And on top of that, those are only the "severe illness" numbers, the "mild/moderate" illness numbers are higher, vaccinated people still spread an appreciable amount, and it's spreading through kids very aggressively now (funny how HN told me just last week that kids were immune and we could reopen schools...)

In short if you want vaccines to actually work and reach herd immunity - you have to slow it down enough with containment measures to slow down the rate of mutation. Because if you just let people get exposed, every exposed person is another chance for the virus to mutate, and it's mutating fast enough that by the time we get everyone vaccinated, the virus will have mutated enough the vaccines are no longer very effective.

(And reality check - we've barely got a start on vaccinating the global population, which is what you really have to do to control it. Vaccines are flowing like water in the US and Europe, and to a lesser extent in other developed nations, but in a lot of the world you just can't get a fucking vaccine even if you want one. A few months ago the number was something like 140 countries hadn't even gotten a single dose of vaccine yet.)

Realistically that is no longer possible at this point. People are done with quarantine and social distancing and 40% of the country won't get vaccinated even when they're free and readily available. And now it's mutated to become several times as transmissible - that's game over. It's over, it's going to become endemic, it's a foregone conclusion at this point.


Actually it's exactly how it works. H1N1 was novel but now it's not. When it first hit, its deadliness was high but not anymore, even as it mutates, which is at a faster rate than SARS-CoV-2.

I suggest you read up on "sterilizing immunity". People with immunity against COVID still can transmit the virus. This was already known so it's nothing new. There are some viruses that we have sterilizing immunity against, like smallpox. There are other diseases like tuberculosis, COVID, etc where immune people still shed the virus.

And you can't stop the rate of mutation because animals can get and transmit SARS-CoV-2. So it doesn't matter if all humans were immune, animals could still get infected and cause mutations that re-enter the human population.


Although mutations arising in an animal population would be evolving to spread better in those animals. More mutation in other animals is probably not as harmful as more mutation in human hosts.


I don't believe it's actually the case that once you are infected by the delta strain your body has lasting immunity to that same strain.

It looks like that also is affected by age and other constraints: https://www.nature.com/articles/d41586-020-00502-w


To not have lasting immunity to the same strain is anti-science. We already know that people who were previously infected by covid are immune to many different variants. To think otherwise would be illogical. Even SARS patients from 2003 have immunity to SARS 18 years later.


The vaccine is a single antigen. A live virus has many antigens. It makes sense your body would have more attacks if naturally infected.


All of the anti-vaxxers were right this time around. What a complete clusterfuck.


No, they're not. It would be a lot worse without the vaccines.

Just compare how things are going on countries where vaccination is not happening vs countries that have a high population already vaccinated and you will see how ridiculous your comment is. Antivax and comments like this only makes things worse.


Not listening to a*holes blindly accepting only one side of the narrative, at least open your eyes to the opposite, or you will never realize when you're right or wrong. It is just science man, it is call antithesis.


What part of more people dying because not having had the vaccine than people die from side effects of having had it? I suppose that's not science to you because it's not in a tweet.


Has anyone looked at the Johns Hopkins COVID map and considered Sweden? Last year they were the country all the lockdown experts vilified (and libertarians envied). Today, Aug 12 2021, among most all western nations they show essentially no delta-bump. How do all you experts blaming anti-vaxers and AstraZeneca scientists looking at Israel explain this data point? What has given Sweden this apparent immunity from delta? It's annoying when inconvenient reality gets in the way of our theoretical science.


Sweden goes into a month-long vacation every July, most business will have 15% or less personnel, people are outside a lot more (and probably out of the cities) if they are in the country.

All of these also helped last year's summer, just look at the graphs, we had a very very normal summertime here, people were going to bars, some clubs, all the parks were crowded and we still got relatively very few infections. Now look at the fall-winter of 2020/2021, massive increase of infections when we aren't on vacations mode anymore and have to stay inside.

Sweden is starting to see an increase of delta-variant cases and by living here and seeing how much people just stopped caring we will definitely see a new wave of infections if delta and/or lambda spread and are really capable of evading the current vaccines.

Please, don't use us as an example if you don't have tacit knowledge of how this society and country works, there are seasonal effects in play that, it seems, you are completely unaware of...


I thought Swedish society was rather similar to that of Finland, Norway and Denmark. Yet they each show rather significant delta-bumps whereas Sweden does not. Good science would ask what distinguished Sweden's COVID response from that of the others and did that have any effect on the difference we're now seeing.


They had a ton of COVID cases (1M, in a population of 10M!) and have vaccinated heavily. They're also doing a lot of the social distancing things that they initially avoided.

Vaccination does reduce the chance of spreading the virus. Having 10% of the country get the natural variant and 45% fully immune, plus still doing the social distancing stuff, and requiring negative COVID tests for those entering the country, seems like a pretty good way of keeping delta under control.


As in every other country the case count is way lower than the actual number of infections. Most infected people never get tested or officially counted. They estimate that about 33% of Swedes had been infected by May 2021 and presumably the number is higher now.

https://www.news-medical.net/news/20210714/e2809cHerd-immuni...

As a comparison point the CDC estimates that about 36% of Americans have been infected.

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...


Yeah, that would be even more consistent with the idea that there's a combination of natural resistance (if not immunity) from the first form of the virus (I think you can get again) as well as resistance for vaccination. It's not going to be 33% + 45% because there'd be overlap in the categories, but that's probably a pretty high rate of resistance.

Couple that with the fact that the Swedes aren't acting completely stupid and are doing a pretty good job of voluntary distancing (not to mention border control) and it seems like the numbers are pretty easily explained. Quite the cost to get there...


Son of a gun, Finland and Norway are not enjoying any of that advantage that Sweden is enjoying. They show rather dramatic delta-bumps. How enlightened of only Sweden.


So, all you have to do is experience a 15x worse outcome in terms of deaths and illness early, in order to have a delta-bump that's half the size (per capita) now. I guess that passes for "enlightenment", at least among the people who are disposed to find that anything Sweden has done is wonderful.




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