Hot take on Omicron - Clue: It's too early to tell.

Some have asked me for some Omicron hot takes. Mine is a boring one. We really don't have much information yet on the variant.

We know it has a lot of mutations on the spike protein. Most likely it was the result of a long-term infection in an immunocompromised individual. Some of the mutations have been seen before in other variants of concern and are known to increase transmissibility. Some mutations are new and we don't know what effect they have. Most importantly we don't know what the overall picture is for this variant. Not every mutation is bad. It isn't necessarily an additive process of badness. Delta Plus for example seems to have less immune escape than Delta.

We don't know if it is more severe. We don't know if it evades the vaccines or prior infection immunity more than Delta.

I'd be most cautious on the early data on the transmissibility advantage over Delta. There's been some scary sounding numbers circulating. We had a lot more epidemiological data for Alpha and Delta than we have for this variant so far. And even then those early estimates generally were larger than the final estimates. Given the super spreading nature of this virus in general these estimates can be very noisy if the number of cases is relatively small as in this case.

We've had some troubling anecdotal cases so far, but we really need to see more data. Immunological data should be available in the next two weeks.

In the worst case scenario where significant vaccine evasion is present the vaccine makers are already at work on an updated variant specific vaccine. This should be available in 2-4 months. They also are testing the effect of standard boosters on this variant and in Moderna's case the effect of a full dose booster as well and not just a half dose.

These vaccines generate a polyclonal immune response, so it is unlikely total evasion will occur. This is especially relevant for severe disease after vaccination. The immune response after infection is also polyclonal, but has much less diversity in regards to the spike protein. So it is more vulnerable to significant mutation of the spike protein.

I don't think if you are vaccinated you should panic for now. I think you should get your booster if eligible as soon as possible. If you are unvaccinated you should get vaccinated. If you were previously infected you should get vaccinated.

The good news is we are doing a good amount of genomic surveillance in the US these days and as of ~1-2 weeks ago Delta was still ~100% of cases. That's an estimate based on state sampling, so there is some noise to it. I assume Omicron is already stateside despite no confirmed cases yet as we already have seen other countries outside Africa have cases with no direct connection to travel. But this isn't like a year ago. We weren't caught off guard by a lot of hidden Omicron cases like we were with Alpha and Delta. So we have a good amount of time to figure out how significant this variant is before it becomes dominant.

We truly just need more information, which should be coming in the weeks ahead.

This should underscore though the importance of global vaccination. Viruses need to infect to mutate. Our best protection against infection, spread, and thus mutations and new variants is vaccination.