More unvaccinated people -> more people getting covid -> more chances for mutation into variants
It's really that simple. We want as few active infections as possible globally so that existing vaccinations can work for the variants they were made in mind with. Otherwise we will be at the disadvantage in a perpetual arms race trying to quickly stamp out the global "fires" of new variants.
If you actually want that, then you need some kind of megaproject to build vaccine factories to supply the entire world and to distribute them to the whole world's population. This virus doesn't respect borders.
Yes in fact, that's the core of what a lot of people have been wanting by trying to get an IP waiver from the WTO. You don't even need new factories, as there's tons of factories out there that are itching to make the various vaccines.
It was my understanding that the developing world doesn’t have the required infrastructure nor qualified workers to manufacture the complex covid vaccines. So the whole patent point is moot.
Your understanding is incorrect, hence the ongoing process for the WTO waiver. Even the mRNA vaccines aren't that crazy, it's a culture of e. coli that's been genetically engineered to produce the vaccines; the manufacturing steps themselves are pretty run of the mill bio reactor stuff with slightly more stringent temperature controls on the tail end. The non mRNA vaccines are pretty much equivalent to any other standard vaccine.
In a world where the delta variant can infect fully vaccinated people fairly easily, aren’t the vaccinated the real problem? The unvaccinated aren’t putting any particular pressure on the virus when it comes to evolving around the vaccines, but the vaccinated are.
Unless we could magically get the cases to zero this problem isn’t going away. Mask mandates will slow things, but eventually you’ll need enough people to actually get infected to drop the replication rate.
Evolution is incremental. To become vaccine evading, the virus has to have a host it can replicate it, and a host that is a resistant target.
In fact it needs a big pool of them, since once infected develop immunity they no longer produce trial mutations.
So you need a pool of the unvaccinated, coming into frequently, regular contact with the vaccinated in order for any specific vaccine escape to evolve.
This is because, any incremental improvement needs to become a population dominant strain within the unvaccinated population: that you survived in a vaccinated person for a little bit is irrelevant if at the end of the day every virus with that trait dies without spreading.
Even if you successfully do spread from a vaccinated host, you need to either land in another vaccinated host (who then spreads you around: so isolation measures are effective), and while you're doing this you need to develop a better escape system: not guaranteed, because if overall viral loading or time to immunity is shorter, that's less time to generate variants.
But...a good way to optimize this, is to just spread to a pool of unvaccinated people. With luck you retain the vaccine-escape mutations, become dominant within the unvaccinated pool, and then get lots of opportunities to try and infect vaccinated people and get a little further.
This, incidentally, why viral evolution tends to consist of "the virus jumped between species several times" - because crossing a species barrier requires ongoing persistent contact between a host you can replicate it, and one you're trying to cross over into.
Right, but aren't you assuming that the delta variant can't go from vaccinated to vaccinated effectively? I don't think we really have solid data on this yet but it seems possible, at the very least.
If that is happening, and the R0 from vaccinated to vaccinated is above 1, aren't we creating immense evolutionary pressure to defeat the current vaccines?
If host A and B are both vaccinated, then either the virus has achieved vaccine escape (it is spreading amongst the vaccinated population effectively), or if it hasn't then it still dies out.
If 1 vaccinated person infects another say 3, but then those people fail to infect anyone else - then it doesn't actually matter what selective advantages that viral strain had - 100% of the virus has died out.
But if the same chain terminates in the vaccinated people then infecting an unvaccinated person...then the new mutation escapes and potentially becomes dominant within the reservoir (unvaccinated people) and a failure to spread through the vaccinated population doesn't lead to the destruction of the mutant strain.
Only the vaccinated will preferentially evolve variants that are resistant to the vaccine. The vaccines are leaky, as evidenced by the recent outbreak in the Northeast. A saner strategy with leaky vaccines is to vaccinate the small population that is vulnerable and let the rest of the population of develop a natural herd immunity. Otherwise you are creating a fitness advantage to resistant strains.
This is not how it works, and "natural" herd immunity has never been a real concept in epidemiology - which it is clear you are speculating on without bothering to read about but should also be trivially obvious from the fact that until vaccines none of the vaccine preventable diseases ever went extinct on their own.
> Herd immunity is a form of indirect protection from infectious disease that can occur with some diseases when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity.
Yes, and wikipedia is not the study of epidemiology.
Epidemiology as a field did not publish papers or study the idea of "natural" herd immunity till last year when politicians started throwing the term around and a whole lot of researcher's scrambled to see whether this insanity had any merit.
Of which the answer is what we already knew just spelled out more specifically: no, this doesn't actually happen in the wild without vaccines, because it's literally just spreading the virus. Viruses burn themselves out after infecting basically everyone, provided immunity is long lasting.
It is misleading though, since this definition is merely ‘flattening the curve’ for the rest of human life, and accepting the increased death rate every year. By contrast, a successful vaccination effort also ‘flattens the curve,’ but additionally substantially reduces the rate of deaths. The latter is what we have observed happen with high confidence in the vaccinated population for COVID: deaths of vaccinated individuals is much less common than for unvaccinated (back of napkin math seems to currently be somewhere between 100-1000 to 1 across most age ranges)
I don't think when people talked about herd immunity they meant that the coronavirus would be wiped out, just that it'd get the replication rate down to a manageable level. Just like those diseases that vaccines wiped out, the young would always be at risk of being infected. In this case though, the young (babies excepted) are also fairly protected from it getting serious.
It's really that simple. We want as few active infections as possible globally so that existing vaccinations can work for the variants they were made in mind with. Otherwise we will be at the disadvantage in a perpetual arms race trying to quickly stamp out the global "fires" of new variants.