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The only thing adding to the "incomplete" escape was previous infection. So points for natural immunity. The previously vaccinated group were very recently doub

The only thing adding to the "incomplete" escape was previous infection. So points for natural immunity. The previously vaccinated group were very recently doubly dosed. The author claims somehow that a booster will help, equating that to previous infection. In fact previous vaccination doesn't seem to do anything given the response was well below detection. Curious why they didn't also test serum from: - unvaccinated and uninfected - single does vaccinated - previously infected but not vaccinated All my confusion evaporated after reading this: "This study was supported by the Bill and Melinda Gates award INV-018944 (AS), National Institutes of Health award R01 AI138546 (AS), and South African Medical Research Council awards (AS, TdO, PLM). PLM is also supported by the South African Research Chairs Initiative of the Department of Science and Innovation and the NRF (Grant No 9834). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript."

reureu 5y ago
The basic epi coming out of South Africa suggests that prior infection alone is wholly insufficient to prevent against infection with omicron (hospitalization and case rates have skyrocketed despite an estimated 90% of the population with immunity from, mostly, prior infection). So “natural immunity” by itself likely won’t help here, and regardless wasn’t tested in this study. My understanding is it’ll take about two weeks for studies to come out with more comprehensive data.
- swader999 5y ago
  Well here's one study that doesn't tell a great story for recently double vaxxed.
  - reureu 5y ago
    I'm so confused by your comment -- it doesn't tell a great story for anyone, regardless of vaccination status. We're all in this together, and a potential escape variant harms both vaccinated (by loss of protection) and unvaccinated (by increased transmission risk since vaccinated aren't protected).
- unmole 5y ago
  > The basic epi coming out of South Africa suggests that prior infection alone is wholly insufficient to prevent against infection with omicron The only study I know of reported a possible reinfection rate of 1.27% for Omicron. While it's higher than Delta, it really doesn't support what you're implying. https://www.medrxiv.org/content/10.1101/2021.11.11.21266068v2 https://www.medrxiv.org/content/10.1101/2021.11.11.21266068v...
  - donavanm 5y ago
    I don’t think that reading is correct. The headline 35k reinfections of 2,796k individuals is for all infections to date. The very recent reinfection data for the last few weeks, which is where omicron is circulating, is much worse: > Based on these analyses, we conclude there was no population-level evidence of immune escape associated with emergence of the Beta or Delta variants. In contrast, the number of daily new reinfections has recently spiked and exceeds the 95% projection interval from the null model, accompanied by a dramatic increase in the hazard ratio for reinfection versus primary infection. The timing of these changes strongly suggests that they are driven by the emergence of the Omicron variant.
    - unmole 5y ago
      > I don’t think that reading is correct. You are right. > The very recent reinfection data for the last few weeks, which is where omicron is circulating, is much worse: I can't seem find the numbers that support this assertion in the paper. How many reinfections occurred during the period when Omicron is believed to have been circulating?
  - reureu 5y ago
    The other commenter already pointed out that the 1.27% isn't really a meaningful data point around reinfection risk (beyond the time issue, it's also a proportion of positives, which doesn't get at what we're really interested in: incidence among those with prior infection). But, more broadly, I wasn't referring to a particular study, but rather the general public health surveillance that's happening in South Africa. There's an incredible rise in both cases and hospitalizations in South Africa, in the face of a relatively low vaccination rate (~30%, although this is 10x higher than most of the rest of Africa) with a relatively high estimated prior infection rate (vaccination + prior infection totaling ~90%). One hypothesis that would explain that is that prior infection offers minimal protection from omicron. That's the hunch that epidemiologists and others start exploring from with studies that will provide stronger evidence in favor or against. There's no answers right now, just data points that need to be taken in the context of uncertainty :-/
Reubend 5y ago
Right, I think the title is very misleading considering the result is that the Pfizer vaccine is 41 times less effective against Omicron compared to the original strain. Or am I misunderstanding the data?
- nojokes 5y ago
  It does not necessary mean this. This only compares neutralizing antibody titers but in real life there are other factors like common viral load. For example antibody titers against original variant and Delta are very similar but still there are many breakthrough cases with Delta because it comes with much higher viral load.
nojokes 5y ago
Maybe they did not test it because it takes a lot time to run actual tests. If you maybe read a little of the study, you could see how fairly complicated it is. They also had to use level 3 biolab that might not be very easily available all the time for them.
- swader999 5y ago
  It took a few days and they used existing methods and techniques. Hopefully we'll get data on the other demographics.

reureu 5y ago

The basic epi coming out of South Africa suggests that prior infection alone is wholly insufficient to prevent against infection with omicron (hospitalization and case rates have skyrocketed despite an estimated 90% of the population with immunity from, mostly, prior infection). So “natural immunity” by itself likely won’t help here, and regardless wasn’t tested in this study. My understanding is it’ll take about two weeks for studies to come out with more comprehensive data.

swader999 5y ago
Well here's one study that doesn't tell a great story for recently double vaxxed.
- reureu 5y ago
  I'm so confused by your comment -- it doesn't tell a great story for anyone, regardless of vaccination status. We're all in this together, and a potential escape variant harms both vaccinated (by loss of protection) and unvaccinated (by increased transmission risk since vaccinated aren't protected).
unmole 5y ago
> The basic epi coming out of South Africa suggests that prior infection alone is wholly insufficient to prevent against infection with omicron The only study I know of reported a possible reinfection rate of 1.27% for Omicron. While it's higher than Delta, it really doesn't support what you're implying. https://www.medrxiv.org/content/10.1101/2021.11.11.21266068v2 https://www.medrxiv.org/content/10.1101/2021.11.11.21266068v...
- donavanm 5y ago
  I don’t think that reading is correct. The headline 35k reinfections of 2,796k individuals is for all infections to date. The very recent reinfection data for the last few weeks, which is where omicron is circulating, is much worse: > Based on these analyses, we conclude there was no population-level evidence of immune escape associated with emergence of the Beta or Delta variants. In contrast, the number of daily new reinfections has recently spiked and exceeds the 95% projection interval from the null model, accompanied by a dramatic increase in the hazard ratio for reinfection versus primary infection. The timing of these changes strongly suggests that they are driven by the emergence of the Omicron variant.
  - unmole 5y ago
    > I don’t think that reading is correct. You are right. > The very recent reinfection data for the last few weeks, which is where omicron is circulating, is much worse: I can't seem find the numbers that support this assertion in the paper. How many reinfections occurred during the period when Omicron is believed to have been circulating?
- reureu 5y ago
  The other commenter already pointed out that the 1.27% isn't really a meaningful data point around reinfection risk (beyond the time issue, it's also a proportion of positives, which doesn't get at what we're really interested in: incidence among those with prior infection). But, more broadly, I wasn't referring to a particular study, but rather the general public health surveillance that's happening in South Africa. There's an incredible rise in both cases and hospitalizations in South Africa, in the face of a relatively low vaccination rate (~30%, although this is 10x higher than most of the rest of Africa) with a relatively high estimated prior infection rate (vaccination + prior infection totaling ~90%). One hypothesis that would explain that is that prior infection offers minimal protection from omicron. That's the hunch that epidemiologists and others start exploring from with studies that will provide stronger evidence in favor or against. There's no answers right now, just data points that need to be taken in the context of uncertainty :-/

Reubend 5y ago

Right, I think the title is very misleading considering the result is that the Pfizer vaccine is 41 times less effective against Omicron compared to the original strain. Or am I misunderstanding the data?

nojokes 5y ago
It does not necessary mean this. This only compares neutralizing antibody titers but in real life there are other factors like common viral load. For example antibody titers against original variant and Delta are very similar but still there are many breakthrough cases with Delta because it comes with much higher viral load.

nojokes 5y ago

Maybe they did not test it because it takes a lot time to run actual tests. If you maybe read a little of the study, you could see how fairly complicated it is. They also had to use level 3 biolab that might not be very easily available all the time for them.

swader999 5y ago
It took a few days and they used existing methods and techniques. Hopefully we'll get data on the other demographics.