One case detected in San Francisco in a Nov 22 traveller from South Africa. Contact tracing may have contained it, all close contacts have tested negative. I still favour travel bans until it's confirmed that we have enough community spread in the US that a few incoming cases won't matter.
It's starting to look to me like Omicron really is unusually contagious, possibly more than Delta. This graph of cases in South Africa, with a corresponding rise in % positive, tells us it's spreading very rapidly and this is NOT just an artefact from more testing. If that curve continues at a similar pace for the next few days, I'd call it strong evidence.
Still not much hard info on severity or vaccine effectiveness or impact on current and upcoming treatments. We'll know a lot more around mid December.
For people reacting with "what's the fuss about Omicron, we've had tons of variants before"...
Check this graph. The vertical axis is the number of spike mutations. Omicron has been evolving entirely undetected for a year and a half, and it has roughly 3x as many spike mutations as the other variants.
A signal like that elicits a reaction like this:
(One of my all-time favorite movie moments.)