1) What do I think about Omicron now that some neutralization data is available? My impression hasn't change. We seem to see a drastic reduction in neutralizing activity, far more than with previous variants. Little activity was left in vaccinated individuals and it is likely....
2)....that very little activity is left in convalescent individuals. However, people who were infected and then vaccinated did have residual neutralizing activity despite a drastic reduction. This certainly also bodes well for vaccinated individuals who received their....
3)...booster dose. While we have no data for them yet, it is likely that they will have residual neutralizing activity. So, my guess - and at this point it is really just a guess - is that vaccine effectiveness against infection in convalescent or 2x vaccinated individuals....
4)....will take a hit and will be strongly reduced. I think protection against infection will remain higher in convalescent vaccinated and 3x vaccinate individuals. I would also speculate, that protection against severe disease may remain reasonably high in all...
5)...individuals with baseline immunity. This is speculation, and this protection may in the end be reduced as well, we will see. The reason why I am saying this is because there are several safety nets. These include residual neutralizing activity (maybe below detection),....
6)...non-neutralizing antibodies (which often target more conserved spots), T-cells and an anamnestic memory B-cell response. The last point is very important, also for potential Omicron specific boosters. It is very likely that the memory B-cell compartment includes B cells....
7)...that target neutralizing epitopes conserved between wild type SARS-CoV-2 and Omicron. The fact that we find residual neutralizing activity in some individuals with high titers can also be seen as evidence for this. Now, when Omicron spike is encountered, either due to a....
8)...breakthrough infection or through an Omicron specific booster vaccine, exactly these cells will likely be activated, they will become antibody secreting cells and increase antibody levels that may neutralize Omicron efficiently within days.
9) All of the above may also depend on the vaccine that was used. Some vaccines will likely provide better protection than others. I am most worried about inactivated vaccines and 'one-shot' vaccines.
10) Now having said all of this, I still think Omicron is highly problematic. If it spreads widely - and the signs are that it will do that - we will likely see another wave. The wave may be less severe in terms of number of deaths because many people will have....
11)...partial immunity. But as we see now with the Delta wave, even in relatively highly vaccinated populations the virus finds those who are vulnerable (because of medical conditions or because they chose to stay unvaccinated) and does a lot of damage. And currently the....
12)...vaccination rate in the US is pretty low. My speculation is that this variant will significantly prolong the pandemic. We have to take it serious. And we need much more data to better understand it.
PS: We are all tired. The health care workers are tired, the researchers are tired, everybody is tired of the pandemic. We all want our lives back. Unfortunately, the virus doesn't care. And we can only get through this together.
PPS: I do not know what all of this means for long COVID.
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