Viewing a single comment thread. View all comments

phred14 t1_jdirlwl wrote

Reply to comment by PHealthy in What happened to the old COVID variants, like Delta? Could they come back? by number1dork

I was under the impression that Omicron and later were better at evading immunity and that nothing worked in a lasting fashion against them - everything wanes fairly quickly.

154

PHealthy t1_jdiztvk wrote

Omicron isn't a single serotype (immune recognition), it's actually a ton:

https://covid.cdc.gov/covid-data-tracker/#variant-proportions

So this isn't waning immunity, it's serotype emergence that escapes immunity.

ELI5: we get a great pitcher versus the first batter but they keep changing batters as we strike them out until eventually our pitcher is terrible. Then we bring in a new pitcher to match against the best batter we've seen so far and it starts all over again.

363

phred14 t1_jdj1pe4 wrote

Thank you for that perspective, it makes me feel much better about things. Not enough better to quit being careful, but still better than I had been.

38

chimpfunkz t1_jdj2jfy wrote

The other half of it is, Even though the batters started hitting instead of striking out, they're mostly hitting singles or doubles instead of home runs. So it's easier to prevent runs from being scored (in this analogy, runs are deaths)

61

mikmckn t1_jdje2qd wrote

And as time progresses, the batters learn to go for base hits instead of home runs because it maximizes their time on base instead of killing the host.

35

northatlanticdivide t1_jdjwo1o wrote

I’ve followed mutations on nextstrain for a while and those of you who are more visual learners like me may find it interesting. It was particularly fascinating watching the rise of delta and it’s being overtaken by omicron. You can also track flu, Ebola, measles, etc.

31

kurai_tori t1_jdjboh1 wrote

This is why the latest booster is based on the mRNA of two variants. Both to increase your immunity to an increased number of variants (there is some cross protection from related variants, depends on how similar the spike protein/antigen is to the original that the antibodies previously produced (e.g. via vaccination).) as well as to increase your "standing army" of antibodies (specific antibodies levels drop after a while, leaving memory cells that will "activate" when reexposed to the Covid antigen (variant-specfic spike protein). Problem is the memory cell response might be too slow, hence the need for boosters of the same variant.

Flu shots are a good example of this and we will likely be moving to a similar approach with COVID.

29

fakeittil_youmakeit t1_jdjbodw wrote

Question for you - I couldn't get the most recent booster due to some health issues at the time. I'm doing much better now and could probably be in a good enough place to do it in the next couple of months or so, at that point, is it even worth it or will the serotypes have changed so much it's not effective anymore? If that's the case are there going to be annual boosters and should I just wait for the next one in October or something? TIA!

9

Tephnos t1_jdk617u wrote

You should still get the bivalent booster now if you can. In the US, it is based off of BA.5, which isn't too far removed from the current circulating XBB 1.5 and BQ1.1 strains.

It is likely that later this year we'll get an updated booster again, possibly targeting XBB if it still sticks around.

27

KruppeTheWise t1_jdk9j3q wrote

Is the fact we vaccinated during the pandemic likely to have put evolutionary pressure on selecting serotypes that can defeat vaccine protection?

1

Psyc3 t1_jdj1meq wrote

You have to take into account what evading immunity can mean. It means it can infect people and they can spread it, it however doesn't mean they have a serious disease or need hospitalisation.

The issue with COVID-19 was lack of any immunity at all, while early variants infected the lungs, later, more infectious variants started to infect the upper airway more seriously, but the reality is while this allows more effective spread, the upper airway is largely irrelevant, it isn't what absorbs your Oxygen supply, it is just causes a really bad cough instead.

Then you have to take into account this issue isn't a disease existing, it is everyone getting it at the same time, and then a significant percentage needing hospitalisation at the same time. Imagine everyone broken their arm at the same time, A+E would collapse, orthopaedics would collapse, any requirement for surgery would be overwhelmed (it is needed in 2 weeks), there would be no ability to get people effective rehabilitation, and people would start dying from complications of broken arms.

That is essentially what happened in COVID, with "a broken arm" being an unknown disease with an unknown treatment pathway, which once again is a massive problem. It is fine if you can treat 95% of your patients with X known treatment, it is another thing when you are trying to work out what treatment is needed, then when you do, don't have the equipment to implement it, or the specialists to manage it.

66

NutDraw t1_jdjtgv0 wrote

>Imagine everyone broken their arm at the same time, A+E would collapse, orthopaedics would collapse, any requirement for surgery would be overwhelmed (it is needed in 2 weeks), there would be no ability to get people effective rehabilitation, and people would start dying from complications of broken arms.

Excellent example. The biggest risk with something like COVID are the huge waves of cases that overwhelm response systems. Sure, the vast majority of hospitalized people will survive with some supplemental oxygen, but if you only have enough tanks and masks for half of them the death rate skyrockets.

25

kurai_tori t1_jdjcc0h wrote

This is why I've been sure to get the lastest booster and am still relatively careful. I don't want to be a cog in the damn viruses' mechanisms. I want my immune system to be able to say "this isn't free real estate".

Cause if you get infected, even if it's asymptomatic, you are a carrier/vector at that point. And you give the virus a chance to thrive, and mutate, and possible mutate to a worse form (viruses can be fatal as long as that still allows them to thrive, and direction of mutation is not always to safer, less fatal forms. Really it's whatever features allow them to outcompete their competitors).

19

mikmckn t1_jdjh59d wrote

If more people took that approach it might have helped early on but eventually it was going to come down to a couple different end games.

  1. We eradicate COVID-19 (sars-cov_2). The fact that there are many different coronaviruses out there would indicate this isn't likely to work. The willingness of this thing to mutate would also seem to be a big speedbump in this road. It's not smallpox.

  2. We beat it back so it's uncommon in this country, like polio or mumps. We'd measure outbreaks in the hundreds and it makes the occasional news report instead of being among the leading causes of death. This MIGHT have been possible with an earlier response that was more restrictive and heavier vaccine use. However, other nations did this and still didn't manage to beat it back before it moved into the 3rd option. China is still trying for zero COVID-19.

  3. Endemic. COVID-19 is here for the long haul. It's in the population. Mothers are going to pass their immunity onto new children. Survivors built antibodies. Vaccinated people built antibodies. Less deadly variants managed to sneak under the radar. We'll be stuck with this long term and probably forever. Coronaviruses are adaptable little jerks. Some just cause cold symptoms. Others cause SARS. Like it or not, we are here.

27

fang_xianfu t1_jdj48aq wrote

"Omicron and later" has huge variation. The variants people are getting now are as different to Omicron as the initial variant was from Omicron. They get named based on how concerning they are - they're Variants of Concern - not how different they are. So when they say "nothing works in a lasting fashion against them" it's because there are many of them.

23

WaitForItTheMongols t1_jdiz0hx wrote

It's important what "immunity" you're referring to.

At this point with the number of variants, it's more helpful to think of COVID as a family of illnesses, rather than an illness. Immunity to other variants won't work against Omicron very well. But if you have immunity to Omicron, it works against Omicron.

15

Nicolay77 t1_jdjaxs7 wrote

I was under the impression Omicron was so contagious and so not-deadly that getting it actually was like getting vaccinated against most variants of Covid.

−3