Omicron largely evades immunity from past infection or two vaccine doses

Re:Omicron largely evades immunity from past infection or tw... by abduhl on Friday December 17, 2021 @01:47PM (#29596491)

What you’re saying sounds correct, but is there any evidence that shows omicron is resulting in less serious illness/death because of the vaccines? The reports seem to indicate that the overall risk profile of omicron is lower including for unvaccinated people. Are we just parroting the same fact as for the alpha/delta variants without any substantial evidence here when we say vaccination helps avoid serious illness for omicron? Why would a variant which has apparently evolved to evade the vaccine continue to react to prior vaccination? We see the opposite with flu vaccines sometimes when vaccinations prime against the wrong strain.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by snewman on Friday December 17, 2021 @01:59PM (#29596730)

Hard information regarding serious illness / death from Omicron is scanty; it's still early. I've read indications that the vaccines (and/or previous infection with another variant, such as Delta) do seem to provide substantial protection against serious illness/death, but I don't have a link handy. IIRC at least some of the data we're working with is based on lab experiments of how various immune system components react to Omicron, which of course is less definitive than clinical outcomes, but is worth something.

> Why would a variant which has apparently evolved to evade the vaccine continue to react to prior vaccination?

This is over-simplified. In particular, "react to prior vaccination" is conflating a bunch of different things, involving antibodies, B cells, T cells, etc. My understanding is that (1) such data as we have seems to generally point toward protection-from-infection being badly eroded but protection-from-illness/death being only moderately eroded, (2) if you're boosted, protection is less badly eroded, (3) all of this seems to fit with our general understanding of how the immune system works. I don't have the domain knowledge to unpack that further.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by abduhl on Friday December 17, 2021 @02:10PM (#29596898)

Your argument boils down to “well the body learns what it looks like and so discriminates against similar looking viruses with more exposure allowing more targeted responses.” Under this theory, shouldn’t a natural immunity (as obtained from prior infection with alpha/delta) result in better immune response because it has learned “more” way to discriminate than the spike protein? Boosters seem inappropriate if the theory is to provide a wide database against which the immune system can check for similarities and associated response because they are targeted at the spike protein.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by astrange on Friday December 17, 2021 @03:00PM (#29597614)

It might, but you don't want to get natural immunity because that would mean getting sick first.

Getting booster shots doesn't simply give you more antibodies, it gives you better ones; each round finds new ways to match the spike protein.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by didjathinkmess on Friday December 17, 2021 @05:22PM (#29599088)

Natural immunity followed by a single dose is the strongest immunity available supposedly. Many of us likely have cross reactive immunity from a previous Coronavirus infection from before the pandemic.

Regarding "better antibodies", that doesn't make any sense to me. More in number perhaps, but better? It's the exact same formula being given as boosters.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by astrange on Friday December 17, 2021 @07:46PM (#29600232)

Omicron does escape natural immunity + no booster though.

https://www.tandfonline.com/doi/full/10.1080/22221751.2021.2...

Similarly, immunity to omicron might not be good at the other variants (which are worse for you), which is why reusing the existing boosters instead of making new ones isn't that bad an idea.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by logic_beats_pro on Saturday December 18, 2021 @03:12PM (#29608091)

I think your first sentence is a bit premature considering the study. Its forgivable to post this because it's so early but seriously, this was done in test tubes.

"One major caveat of the current study is that we used an in vitro assay system and the pseudotyped viruses but not the real viruses were used in the assay."

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by Volundr on Friday December 17, 2021 @06:46PM (#29599730)

We train neural nets on the same training sets for multiple iterations and expect it to come up with new/better connections. When learning a new skill we may meditate on previously solved problems and discover better solutions. Why would the immune system not have the capability to continue experimenting and learning from the same stimulus?

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by hackerfromthefu on Friday December 17, 2021 @03:48PM (#29598148)

Can you provide a reference for this, as I thought the boosters were just the original vaccines, hence exactly the same antibodies.

Yesterday I read that the customised omicron specific boosters being developed by pfizer and moderna are not going ahead as the existing boosters are deemed good enough, though I can't find the link for that now.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by astrange on Friday December 17, 2021 @04:02PM (#29598316)

They are the original vaccines. I suppose it works by giving your body another chance to study them.

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by tfehring on Friday December 17, 2021 @04:46PM (#29598736)

Two doses of Pfizer's vaccine reduce hospitalization risk from Omicron by ~70% based on data from South Africa, with similar reductions across all age cohorts from 18 to 79. https://www.linkedin.com/pulse/discovery-health-releases-cri...

[ Parent | on HN ]

Re:Omicron largely evades immunity from past infection or tw... by ugjka on Friday December 17, 2021 @01:52PM (#29596580)

give it a month or two and we'll see who's right or wrong

[ Parent | on HN ]