Omicron will make up at least 1% of cases in the US by Dec 31. Which means it could make up substantially more than that. However, in mid-December when you’re traveling and going to solstice, it probably won’t be that high—and even if it’s 5 or 10% at that point, that’s not going to have a major effect on the state of COVID.
Not sure when this post was written, but I think this is an extreme underestimate at this point. For instance, my own current median guess for Omicron overtaking Delta in the Bay Area specifically is early this coming week. This is based on eyeballing doubling rate estimates in Zvi’s posts, and guessing how our initial conditions could plausibly compare to London or Denmark. (This wasn’t a careful calculation, but the exact initial conditions don’t actually matter that much because the doubling rate is so fast, so a factor-of-two in initial conditions only changes the takeover date by 2-3 days.)
I expect that using the Polymarket predictions as a proxy here will severely underestimate Omicron’s timeline for two reasons. First, those predictions are for the whole US; we’d expect it to hit first and fastest in major urban centers with a lot of international travel (as we saw in e.g. the UK). Second, those predictions are about what the CDC data says on Jan 4, which means there’s a ton of lag built in—both from the usual lag on data, and from the holidays slowing things down.
Even given all that, Polymarket currently gives an 83% chance that Omicron will be >50% in the US as a whole on Jan 1, based on the CDC’s data of Jan 4.
Not sure when this post was written, but I think this is an extreme underestimate at this point. For instance, my own current median guess for Omicron overtaking Delta in the Bay Area specifically is early this coming week. This is based on eyeballing doubling rate estimates in Zvi’s posts, and guessing how our initial conditions could plausibly compare to London or Denmark. (This wasn’t a careful calculation, but the exact initial conditions don’t actually matter that much because the doubling rate is so fast, so a factor-of-two in initial conditions only changes the takeover date by 2-3 days.)
I expect that using the Polymarket predictions as a proxy here will severely underestimate Omicron’s timeline for two reasons. First, those predictions are for the whole US; we’d expect it to hit first and fastest in major urban centers with a lot of international travel (as we saw in e.g. the UK). Second, those predictions are about what the CDC data says on Jan 4, which means there’s a ton of lag built in—both from the usual lag on data, and from the holidays slowing things down.
Even given all that, Polymarket currently gives an 83% chance that Omicron will be >50% in the US as a whole on Jan 1, based on the CDC’s data of Jan 4.
Good point re the urban centers, was pretty dumb of me to forget to adjust for that. I’ve added two ETAs to the post to account for this.
And now omicron is at 74% of US cases!