The first big study out of South Africa on the Omicron variant’s relative severity is out, and the initial news appears to be very good.
Omicron infections were associated with an 80% reduction in hospitalization risk relative to concurrent Delta infections, and a 70% reduction in risk of severe disease compared to previous Delta wave infections.
Now all this no doubt comes with all sorts of caveats regarding how different populations vary a lot in regard to various risk factors, and their associated vulnerability to this variant. Nor is it clear at this point how much the striking reduction in observed severity is a product of acquired pre-existing immunity in the subject population, either via vaccines or previous infection, as opposed to an inherently less severe variant. A further caution is that if you get one-fifth as many severe cases per infection but five times as many infections because of the variant’s extreme transmissibility, that’s kind of a wash statistically, at least in the short run.
So lots of caution is warranted . . . But as a mostly terrible year comes to a close, I’m happy to take whatever apparent good news I can get.