Submitted by Esc_ape_artist t3_11asu19 in askscience
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[deleted] t1_j9twimf wrote
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PartyOperator t1_j9tymcj wrote
There’s likely to be some cross-reactivity between human immunity to circulating influenza viruses (especially H1N1) and avian H5N1, but whether it’s enough to prevent (or reduce the severity of) disease is unclear.
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Ch3mee t1_j9u2uoc wrote
But, this is good, even though the vaccine is different. Because a vaccine is already developed. It wouldn't be a significant change to include vaccination against this into current flu vaccinations. That, and we already have quite a lot of experience with flu vaccines. So, this saves a lot of development and approval time on deployment. That's awesome. Now, the current populations education level regarding vaccination is less awesome.
[deleted] t1_j9u420y wrote
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Corrupted_G_nome t1_j9u46oc wrote
According to the info sheet from the government of Canada some treatments and medicines exist to limit symptoms and mortality. There may be some minor benefits to the related vaccines.
sciolycaptain t1_j9u48fn wrote
Making influenza vaccines is something the world has experience and capacity to do (because we do it every year), however current techniques still have a bit of lag between identifying a novel strain and then development and mass manufacturing.
If we looking at the 2009 H1N1 outbreak, it took about 6 months to have a specific H1N1 vaccine approved and distributed after the first human cases.
With mRNA vaccines, which they are looking into for influenza, the turn around time may be significantly shorter.
Corrupted_G_nome t1_j9u4dqo wrote
My government already has plans and an info sheet in play. Good to know someone is taking this very seriously. Better to make policy before potential outbreaks.
Corrupted_G_nome t1_j9u4g95 wrote
Some but not much according to this.
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ZipTheZipper t1_j9u6bi5 wrote
> Now, the current populations education level regarding vaccination is less awesome.
Covid's case fatality rate has leveled off to roughly 1%. SARS was estimated at 10%, and MERS was 34%. This strain of H5N1 is above 50% right now. If it becomes easily transmissible between humans, either the antivaxxers change their minds fairly quickly or the only people left will be ones who believed in vaccination.
[deleted] t1_j9u6tvn wrote
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DiceMaster t1_j9u7jlq wrote
How long can flu vaccines last in cryo storage? Could it make sense to have tons of h5n1 vaccine stockpiled just in case?
sciolycaptain t1_j9u8fp0 wrote
Influenza vaccines can't be frozen without having decreased efficacy. They have a narrow window of temps they can be stored in a refrigerator, and once room temperature, must be used within 72 hours.
NotAnotherEmpire t1_j9u8ok4 wrote
Tons, no. We don't know what the antigens of a future pandemic strain would be.
The USA does try to keep an updated stockpile of H5N1 vaccine, at least enough for doctors, first responders and the armed forces.
christophersonne t1_j9u8xl5 wrote
There have been very few infections in Humans over the last 25 years (under 1000 confirmed last time I checked), and mostly they happen in places that a flu vaccine isn't widely available or used. So, we really have no idea in a real-world sense.
The problem with H5N1 that could cause serious problems is a mutation/variatnt that would allow for human-to-human transmission , which the current variant doesn't have - so a human-affecting pandemic of H5N1 would be a fundamentally different variant to the strain(s) we know of today.
The mutation needed to H2H transmission may or may not affect the protection afforded by a flu vaccine. Think about how different Covid has been, variant to variant, and with the various vaccines we have.
(tldr: more data required)
ChickpeaPredator t1_j9u9wbq wrote
>If it becomes easily transmissible between humans, either the antivaxxers change their minds fairly quickly or the only people left will be ones who believed in vaccination.
Evolution in action, people: move with the times or remove yourself from the gene pool. It's incredibly sad, and I wish it weren't like this, but if you can't be persuaded with logic to do something for your own safety and the safety of others well... there's a point at which we can't do any more for you, and we have to let nature take its course.
Edit: in case it wasn't obvious, my comment above is in support of vaccination.
DiceMaster t1_j9uahwa wrote
"Cryo" may not have been the exact word I was looking for. How long do they last, sealed and in a fridge?
The_RealKeyserSoze t1_j9uak8y wrote
We don't really stockpile flu vaccines because influenza changes and so older versions would not be very helpful. Instead we stockpile the raw materials and production capabilities for the vaccines. The traditional flu vaccine is made using chicken eggs infected with the virus so many countries have their own emergency supplies of chickens/eggs for this purpose.
Now that we also havecell based flu vaccines that don't require chicken eggs as well as future mRNA based flu vaccines that can be rapidly mass produced there will likely be a variety of of options for stockpiling/emergency preparation.
DiceMaster t1_j9uazju wrote
> The USA does try to keep an updated stockpile of H5N1 vaccine, at least enough for doctors, first responders and the armed forces.
That's sensible. Do we know how effective the h5n1 vaccine is, given that bird flu is so rare in humans to begin with?
Esc_ape_artist OP t1_j9ubn2v wrote
Good point. The potential H2H variant could render the current H5N1 vaccine useless.
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Beat_the_Deadites t1_j9uflqo wrote
Evolution also in action - different strategies for responding to evolutionary pressure.
Group A: moves cautiously and with extensive forethought. Acts slowly but with higher success rate and longevity. Reproduces below replacement level.
Group B: Shotgun approach, devil-may-care attitude. Pops out kids like a mushroom releasing spores. Overwhelms evolutionary pressure by sheer volume. Some offspring migrate over to Group A, keeping the two groups in some sort of balance, if not harmony.
Whiterabbit-- t1_j9uhkgw wrote
why is mrna shorter time to market?
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Ch3mee t1_j9uj9nh wrote
I was responding to a post saying there is already an H5N1 vaccine developed. I don't know if that's true, but its not that unbelievable it could be. My point is that if the H5N1 vaccine is already developed, then that significantly shortens the timeline. The lag just becomes the manufacturing ramp, but that can be retooled fairly quickly, and supplies can start moving almost immediately. The lag will be from the first people to get a dose to supply for the eventual demand. That can be slow, but with some planning and foresight, batches of vaccines can be deployed following patterns of outbreak. Basically, instead of months, vaccines could start hitting problem areas in days if there is already some inventory or weeks as production starts on an approved formulation.
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Ch3mee t1_j9uki9u wrote
I mean, in the simplest scenario, Group B wins. Simply because group A is self selecting themselves out by reproducing below replacement level. I mean, the whole name of the game is ability to reproduce successfully. If Group B is popping out kids like a mushroom releasing spores, then they're brute forcing the reproduction game.
Of course, nothing is that simple. If the devil-may-care attitude ends up with the group not getting a vaccine during a very deadly pandemic, they could be eliminated almost entirely.
Yancy_Farnesworth t1_j9ul5fz wrote
> Because a vaccine is already developed.
People really don't understand how much effort is expended annually to update the vaccine for flu season. The flu virus mutates really easily unlike COVID. It's why we have an annual flu shot. If someone is infected with multiple flu variants, the variants literally start swapping parts creating essentially a new strain. We've been developing new flu vaccines every year for decades. It's not just a few tweaks every year, it's literally a new vaccine every year.
The WHO is responsible for tracking flu strains going around the world and creating the vaccine for that year. This requires a lot of tracking of flu cases world-wide and analyzing the strains going around and creating a vaccine that targets the strains going around. And there are a lot of strains circulating, it's literally impossible to vaccinate against all of them.
BlueOmega169 t1_j9ulafx wrote
The development pipeline is substantially shorter, if you can produce an mRNA vaccine you can theoretically produce any mRNA vaccine. Once you have the genetic sequence of the strain you're interested in, preparing one mRNA transcript is (more or less) the same as preparing any other. The same is not true for protein expression or live attenuated virus preparation. Preparing the vaccine at scale faster means getting to testing sooner, and testing sooner means results sooner.
gwaydms t1_j9ulttt wrote
>2009 H1N1 outbreak
I caught that before the vaccine came out. It made me pretty sick (fever, chills, headache, dry cough). My symptoms were typical for that strain. And it was summer, not exactly prime flu season.
In those early days, brain and/or lung involvement was causing severe and even fatal disease and I didn't have that. I stayed in bed and just rode it out.
Beat_the_Deadites t1_j9un7qy wrote
Sure, my example is way over-simplified, and group B will always have a higher mortality rate, which could be disastrous for them in a pandemic with a high death rate. But the survivors of that pandemic are going to think themselves extra special and try to repopulate the globe again.
Using the tools provided by Group A, of course.
[deleted] t1_j9uon40 wrote
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sciolycaptain t1_j9uoxo9 wrote
The current influenza vaccines are made by incubating the virus in fertilized chicken eggs. That step takes time. and hundreds of millions of eggs.
With mRNA vaccines, you can just throw templates, nucleotides, and enzymes into a container and get more mRNA for the vaccine (extremely oversimplified)
Fenrisvitnir t1_j9uqbsg wrote
Personally I wouldn't have flu rooms in my house, but to each their own.
boooooooooo_cowboys t1_j9uqop3 wrote
I don’t know that there is much solid data to address that question. Typically flu vaccines are tailored to whatever strains are circulating in a given season, so they’re just thrown away at the before the next flu season.
decrementsf t1_j9uqtl0 wrote
No. The flu vaccine begins production a year before flu season. What is used that year is based on prediction a year out of what next seasons flu will be. Ask your friendly finance guy how accurate prediction models are as you throw a dart into the future. Historically the prediction has a poor record with actual experience.
The treatment should match the risk. If you are older or at increased risk for other reasons, well maybe doesn't hurt offers some chance at benefit. You do you.
IslandDoggo t1_j9ur288 wrote
Part of what made covid a problem was it being novel. H5N1 means a lot of awful things for us, potentially. But it is not novel. We know this enemy.
aphilsphan t1_j9urj8k wrote
There will be solid data somewhere, and generally an expiry date on the label. The manufacturer would have done or sponsored shelf life stability tests.
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Ch3mee t1_j9usoac wrote
You lost me at the "unlike Covid" where we have been through like 6 major variants, with a few dozen minor variants, inside 2 years time.
Usually, a flu vaccine isn't one strain. The vaccine is a combination of several strains that researchers believe will be predominate that year. But, even subvariants of strains don't require absolutely new development of vaccine. It depends on the anti-gen of the strain. Amd this mostly deals with flu A. Flu B is a bit different. Vaccines will have B and a few strains of A in a yearly shot.
swiftb3 t1_j9uuhl4 wrote
> The flu vaccine only protects against specific strains of the flu virus that are expected to be around in the upcoming flu season.
Directly, though you do get some level of partial immunity to other similar strains of flu. Whether there's enough overlap with the H5N1 for any partial recognition, I don't know. I'm sure not enough to be significant.
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ThellraAK t1_j9uw5u9 wrote
Isn't most of the delays in it regulatory stuff?
There were people DIYing COVID-19 vaccines as early as July 2020
Yancy_Farnesworth t1_j9uwkrk wrote
> where we have been through like 6 major variants, with a few dozen minor variants, inside 2 years time.
That's the point? It's a relative comparison between the flu virus and the COVID virus, not a claim that COVID doesn't mutate. We would be in deep trouble if COVID had the same potential to mutate that the flu virus does. We're lucky that the flu virus doesn't have the same level of immune evasion/suppression that a lot of coronaviruses have.
xanthraxoid t1_j9uyoii wrote
It's worth noting that these tests aren't completely comprehensive. Recall that the nominal shelf life of various Covid vaccines was extended a couple of times - the initial results were interpreted conservatively, but over time more evidence allowed a more confident prediction of a longer shelf life.
When it comes to a vaccine that's not expected to be useful more than ~6 months into the future (nobody's taking the flu jab in the spring, and next year they'll want the new one) there's not really much point in measuring how it lasts beyond that with any degree of rigour.
Providing the shelf life is expected to be good enough for "this year's flu season" (3 months?) they'll most likely just use that figure and move on to more valuable work.
xanthraxoid t1_j9uyz4e wrote
Emergency Chicken Stockpile is a combination of concepts I didn't expect to encounter today...
Doc_Lewis t1_j9uzj6n wrote
It likely has some effect, but specifically it is not targeted to the H5N1 influenza A virus.
Flu vaccines target the H and N glycoproteins, so it would depend on which epitopes of which H and N was in the flu vaccine this year, and how much homology there is between them and H5 and N1.
My gut says it's probably measurable, but not significant enough to really offer any protection.
ChickpeaPredator t1_j9v0qcy wrote
The group B approach is exclusively used by organisms with low offspring investment. As the amount of investment goes down, the quantity of offspring increases.
We aren't like that - it takes a humongous amount of resources to raise a functional human. So we either slip backwards from our humanity and become simpler organisms with less offspring investment required, or we have to expand infinitely to gather enough resources. The latter is impossible, there's always going to be some limit to expansion, so we would be left with the former; backsliding.
You're right in that option B is a viable evolutionary strategy, but it's not a world in which I want to live. I'd rather be a person amongst peers than a king amongst idiots.
daniel_joffre t1_j9v1jsp wrote
No, and it doesn’t even always offer protection against the regular flu viruses either. They have to guess ahead of the upcoming flu season which strains are going to be prevalent, and if they’re wrong then the flu shot carries zero efficacy (and sometimes its efficacy even has a negative value).
doogle_126 t1_j9v2a8k wrote
Does that include mRNA?
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somewhat_random t1_j9v9x5w wrote
If the annual flue vaccine is based on "best guess" from the strains circulating in the opposite hemisphere the previous year, could they nit just include H5N1 in the vaccine for next autumn or is it already too late for that?
LonelyGnomes t1_j9vank4 wrote
LonelyGnomes t1_j9vb0nr wrote
I feel like that’s exactly how I’ve done PCR every time (plus some buffer and magnesium). It’s kinda magic.
Intern11 t1_j9vb4jp wrote
That vaccine will only protect you from the current variant of the bird flu which only passes from birds to animals. If the virus mutates and transforms into one that can pass from person to person we would need to engineer a whole new vaccine which wouldn’t be worked on until we found the dominant strain of the new pandemic.
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PhoenixReborn t1_j9vbscq wrote
Flu strains mutate rapidly. That's why they're updated and administered every year. We have a vaccine, but it hasn't been designed for the current sequence. The typical turnaround time for the annual flu vaccine is six months.
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nirad t1_j9vfteg wrote
It seems like we should probably be stockpiling that, even if it ends up going to waste. And we should be inoculating people in the developing world who work with birds.
zeocca t1_j9vhrmw wrote
>This vaccine is not part of the routine flu shot schedule and is usually only recommended for people who work with birds or people who are traveling to areas where the virus is known to be present.
Where have you read this? We have a vaccine in development, but no responders nor poultry workers are being vaccinated for this specific strain. Is this in a specific country? Is it attuned to this specific strain? I know of an older one developed by Astrazenaca, but it is only for those 18 or younger. Nothing for the current situation is in use that I am aware of.
velawesomeraptors t1_j9viibb wrote
Hm, speaking as an ornithologist who works directly with wild birds, do you know how difficult it is to obtain a vaccine? My boss keeps bringing up bird flu in staff meetings and I feel like a vaccine would at least make her less worried.
annaheim t1_j9vjs18 wrote
Is H2H transmission mutation similar to all diseases? Like, if it's composes of the same component. Can fungus evolve to have this mutation?
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deathputt4birdie t1_j9vpt07 wrote
FYI, there are eight H5N1 vaccines that have been approved by either the FDA or the EU. None are currently available for civilian use.
punkrockscience t1_j9vq5l5 wrote
Not much - but in a way, that’s a good thing!
The current vaccine is made for human flu variants. Avian H5N1 is currently pretty different from the circulating human variants that the vaccine targets. While this is why the human vaccine offers little protection against avian H5N1, it’s also why the likelihood of you catching avian H5N1 from a bird is relatively low.
The human flu viral variants have evolved to fit human cellular surface proteins, not bird ones, and the antibodies the vaccine generates are to the human viral variants. The avian flu variants have evolved to fit avian cellular surface proteins, which don’t look a lot like human ones.
As long as the avian virus is only fitting well to avian proteins, it will stay difficult for humans to catch it. Weirdly, if the human vaccine were to start offering us more protection - because the avian virus had evolved to start fitting human proteins better - we’d be in more trouble.
punkrockscience t1_j9vqnku wrote
Prediction of what goes into the yearly vaccine is about a year or more out from the flu season it gets administered in. To make the flu vaccine, the flu virus (or viruses, since the seasonal vaccine usually contains multiple strains) has to be cultured in millions of eggs, isolated, purified, combined, and turned into vaccine. It’s a very slow process.
This is one of the reasons that an mRNA vaccine for flu could be such a groundbreaker. The turnaround time is potentially much shorter.
NotAnotherEmpire t1_j9vtck8 wrote
We don't "know know" because the infections are so rare and the virus is so dangerous. This is not a virus where one would do human challenge tests.
We do know what a successful flu vaccine match looks like though, and in animal tests (like the one linked) it shows what we want to see.
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alwaysjustpretend t1_j9vv6ts wrote
Yup. Inoculation > incubation >candling > harvesting > first filtering > centrifuge filtering > sterile filtration > more sterile filtration > filling> packaging >shipping.
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phonetastic t1_j9w761t wrote
Dead on. Since I know a lot of people who don't speak Science come here to learn, let me phrase it for them, too:
It likely has some effect, but specifically it is not targeted to the H5N1 influenza A virus.
The way vaccines work is by teaching your immune cells to target specific proteins on a virus (viruses are made up of many, many proteins, just like you and me). Now, different proteins have different shapes, so it's important for the vaccine to have the right counter-shape. Think of puzzle pieces. Anyway, if there's enough similarity in the proteins between HxNz and HyNw, then yeah, it'll do something, but it won't be perfect. Otherwise it'll do nothing at all.
Because they are all kinda similar, it probably does something, but not enough to really help. Part of the problem is that if you don't kill enough mean little microbes, it just doesn't matter. Going to Australia and shooting fifteen rabbits is not going to reduce the need for a rabbit-proof fence, right? So you gotta do better or you should've just stayed home.
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BenjaminGeiger t1_j9wkanu wrote
Emergency Chicken Stockpile is the name of my They Might Be Giants cover band.
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sciguy52 t1_j9x5j9q wrote
Maybe a little but it will be really small. Current human yearly flu includes H1N1 which is in the vaccine. So H5N1 has an N1 in it which might allow a small amount of cross reactivity. BUT the N1 in our vaccine is not designed to target the N1 in h5N1 which will be different, probably a lot different. Think of it this way, when we have H1N1 viruses dominate a few years in a row you need a new vaccine each year AND the H1N1 variants are not hugely different from one another as the evolutionary change is small from year to year. The N1 in H5N1 is going to be a lot different comparatively. So a tiny bit of immune response is better than none, but if H5N1 turns into a very infectious virus for people with high mortality, I don't think that tiny bit of immunity is going to make much difference. There are a bunch of other bird flu's out there we also keep an eye on like H7N9, H7N7, H5N9 and more and for those we have no immunity, although H5N1 is probably the biggest near term worry due to it widespread infection in birds worldwide right now and some passage into mammals.
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Botryllus t1_j9xd7fx wrote
Could they get a head start on a vaccine by looking at a conserved protein in virus so that they're ready if it jumps?
amestrianphilosopher t1_j9xex6m wrote
Why does it only “do something”? It feels like it should be black and white, like “it has this protein, therefore I’m somewhat protected against it”. Like, how much of the protein has to change in order for it to not be effective?
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Dr_Vesuvius t1_j9xme1z wrote
No, not at all. Human-to-human transmission is not a biological component, like a human leg, but a biological process, like movement. There are many different things that go into human-to-human transmission, but it comes down to getting into the body, reproducing, and getting out again. There are many different ways to achieve those things. The flu is spread very differently to HIV, which is spread very differently to malaria, which is very different to Legionnaire’s Disease.
Edit: although to clarify, Legionnaire’s Disease isn’t usually spread human-to-human, and malaria is debatable. Cholera would be been a better example of a waterborne disease that enters through the digestive tract.
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Chemputer t1_j9xmjgs wrote
Pretty much. It's one thing if you are confident enough in your own work to dose yourself, but you definitely want to know the efficacy and safety profile before you dose millions of people with it, so we do kinda need the regulatory stuff, even in a pandemic we still had essentially the bare necessities of it. I'm convinced that it was slower than it could've been at "bare necessity" speed because they were also proving the safety and efficacy of mRNA vaccines for the first time, so in the future we wouldn't need to go as slow.
Dr_Vesuvius t1_j9xmptp wrote
Disease isn’t black and white. The extreme options are “you don’t feel sick” and “you die”. There are a whole spectrum of options between those two.
A vaccine that is providing a lot of protection will dramatically reduce your symptoms, and might stop you feeling sick at all.
A vaccine that is providing some protection might cause you to be sick for 50 hours instead of 52 hours, and be in slightly less pain during that time.
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liamisabossss t1_j9xnk1v wrote
Think of it like fighting fire with water. If you have a long thin line of leaves and start a fire at one end, and you have simply a small hose or a water gun, you can stop that fire. Now imagine a house catching fire. You have the same hose as before, and water fights fire so it should at least help right? You might be technically reducing the total amount of flames on the house with the little hose, it’s measurable, but if you’re not blasting it with enough water, it’s just going to keep growing. You need enough protection to actually combat the totality of the situation.
fuzzybear3965 t1_j9xp1id wrote
Thanks! Does
> HxNx and HyNy
mean
> HxNz and HyNw
?
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PirateNinjasReddit t1_j9xsy9e wrote
It's unlikely to render it useless. Most likely it would just be less effective. Like how COVID vaccines offer more or less protection from variant to variant, but never do they offer no protection at all.
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Onetwodash t1_j9xz29b wrote
Current vaccine is h1n1+h3n2+B+B
So N1 is included?
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phonetastic t1_j9y0425 wrote
All squares are rectangles, but not all rectangles are squares. And parallelograms are kinda rectangles, but not. Think of a door when you're building a house. A one-degree shift in the angles on the door might still fit the frame. A ten degree shift won't at all. Seems small, but it's functionally massive.
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platoprime t1_j9y53wa wrote
How different does a virus need to be for a vaccine to be useless? Or does a vaccine protect against all viruses a tiny bit?
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Taboc741 t1_j9ykeyh wrote
Viruses on their outside are a collection of well fitting proteins. It turns out the shape of a protein is very important, it lets the protein do its "job". Or as much of a job as a physical shape can have. Think of a hammer, its shape makes it very good and driving nails but not very good at smoothing concrete. These viral protein shapes allow the virus to attach to human cells, open the cell wall and "inject" the malicious genetic code to the cell. Antibodies attach to those protein shapes and can rip apart the virus, make it easy for immune cells to find and destroy, and/or prevent the virus from attaching to human cells.
Each mutation in a virus alters the proteins and their shapes a little. Too much mutation and none of the parts fit and it is no longer self replicating. So asking how different does it need to be is a very difficult question to answer. A little bit and the various shaped antibodies the body produces will still bind to some of the virus's protein shapes, a little more and it might stop attaching to human cells (though it might attach to a different animal cell and thus you've found a variant that is ready to hop species), and too much more and now you've either killed the virus or it's something new entirely.
Tldr: these mutations affect the very being of the virus, too many and it stops being the virus it is.
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