Hacker News Reader

Comment by thdrdt | Hacker News Reader

There are already 2 known virus mutations: G614 and D514. In Italy new research suggests even a 3rd mutation might go around. And Denmark also had a mutation.

Do those vaccines work on all mutations or are they like the common flu vaccines that must be adapted every year?

View on HN

Yes for now, but “We need to keep our eyes open for additional changes.” https://www.nature.com/articles/d41586-020-02544-6

This site tracks all the strains: https://nextstrain.org/sars-cov-2/

Derek Lowe just published a blog that addressed this (and other) questions: https://blogs.sciencemag.org/pipeline/archives/2020/11/18/va...

To quote his summary:

> Bottom line: the coronavirus can’t undergo the wholesale changes that we see with the influenza viruses. And the mutations we’re seeing so far appear to still be under the umbrella of the antibody protection we’ll be raising with vaccination, which argues that it’s difficult to escape it.

All mutations share the same spike protein, which the vaccine targets, and as far as we know the virus cannot reproduce without that exact same spike protein. Having the virus mutate in a totally different but still successful spike protein should be very very unlikely.

AFAIK the spike protein is used by the virus to gain entry into cells, it's not strictly related to reproduction. In theory the virus could mutate to gain entry into the cells via a different mechanism.

That is very strange claim. D614G is a mutation in the spike protein, and also there is a document ed case of very rapid mutation of the spike in an immuncompromised patient.

Do we know how widespread those mutations are

Danish authorities believe the mutation "cluster-5" is extinct now.

I talked with a Spanish scientist that has developed a vaccine for covid and other vaccines for other illnesses before that.

He said something like that most of the work in testing is for the "carrier" or something like that(in Spanish). Once your vaccine works with that you could modify the vaccine very fast with little consequences.

Hew also told me that you can share "carriers" for different illnesses and he had tried to convince politicians for decades trying to create "generic carriers" in order to be prepared for something like this.

Does this new generation of mRNA vaccines even have carriers in the conventional sense?

But when you can change payloads of a pre-validated generic carrier at will you are roughly on the same level of biotechnological advancedness as the mRNA companies anyways, both are lightyears ahead of ancient techniques like breeding weaker viruses in animals or neutering them somehow before injection. A lot of vaccine skepticism seems to be based on the performance of those old ways, it would probably be quite wise to avoid a vaccine that was come up by old trial&error methods in less than a decade.

Yes, at this time, all virus variants have the same spike structure where the vaccines and commonly produced antibody responses to vaccine/infection target.

Oddly enough, the G614 mutation is moderately more vulnerable to neutralization.

Once enough people are no longer susceptible/vaccinated, there may be considerably more selective pressure for the virus to mutate in ways that antibodies to past variants don't work. Whether we'll get variants that are virulent and bypass immunity is TBD. The spike protein is functional; changes to it that bypass immunity likely reduce function.

Is it correct that once enough people get vaccinated, even if we don't eradicate the virus, it will have to mutate into something milder in order to still effectively spread?

It is not a given that it will be milder, just estimated to be more likely once everything is taken into account.

As an example of why, the comment you are responding to mentioned the spike being functional (it is used by the virus for cell entry) and it is also targeted by our antibodies. So, for the virus to evade antibodies, it would have to change the spike enough so that antibodies don't detect it anymore. But, by changing it would likely lose some of its current efficacy.

There's some nuance to this. The current most common strain is theoretically the most genetically fit strain. Wide use of vaccines targeting conserved regions of the spike protein almost certainly would result in less genetically fit virus progeny becoming more common by simple selection. But, there's no predicting the virulence of the the less genetically fit strains that will pop up. ie) very deadly viruses aren't necessarily very genetically fit. The short of it is, the resultant strains will probably be less transmissible (the "R" number will decrease), but it's hard to predict their virulence/serverity.

I think consensus is we don't know for sure, but there's reason to be hopeful. SARS-CoV-2 probably won't evolve as fast as the flu, which undergoes a "sexual-like" evolution process called "re-assortment." On the other hand, CoV-2 has "re-combination," which gives similar results, and it does have zoonotic hosts.

Yup, this is a good answer.

Note there is some correlation between virulence and severity. For something with a longer incubation time, increased viral load tends to mean both increased virulence and transmissibility. This relationship is far from universal, though.

>The current most common strain is theoretically the most genetically fit strain.

Why? Has it had a ton of time to evolve?

I thought that these vaccines were targeting the spike protein which seems to be unique to these viruses. Hopefully that would make them easier to vaccinate against.

IIRC this particular vaccine targets the "spike protein", which is shared between all known COVID mutations.

The variants named here have differences in the spike protein. But the portion targeted by the vaccine candidates is the same.

https://www.medrxiv.org/content/10.1101/2020.07.22.20159905v...

There is obviously no way to know that.

They just finished the first study on the regular virus yesterday!

Reply on news.ycombinator.com