Omicron Details, Omicron and New York City

Omicron is a new variant of COVID-19.

Omicron was first identified in Botswana and South Africa. It may have originated elsewhere.

Omicron is more different from previous variants than other previous variants had been.

When Omicron was first sequenced, it was already more different than previous variants, which may indicate that it was developing for a while, which may make its ultimate origin not Botswana or South Africa.

There are several competing theories about how this could have happened:

• It could have developed and mutated as a long-term infection in an immuno-suppressed person – that would have given it time to become very different, while not being detected.
• It could have passed from person to animal, and back to person.
• It could have happened when a person was infected with two variants, and those variants recombined, swapping parts, creating a brand new variant.
• It could have been around for a long time, and we were just not looking for it.

I think the top of the list is more likely than the bottom.

Omicron is definitely more transmissible, by a lot, than other variants of COVID-19.

Omicron can infect vaccinated and even boosted people.

Is Omicron less severe than other variants? That’s an important question. And the answer? Maybe. We are seeing infections that are in general less severe – but is that intrinsically omicron, or is that because so many omicron cases are reinfections, cases in people who already have partial immunity? In South Africa omicron found a population where vaccination rates are only 25%, but where many people had already been infected – so it is not clear if the cases were less severe because that’s how omicron is, or if the already-infected and the vaccinated just have milder cases. I’m hoping omicron is just less severe, but we should be watching closely.

How fast does Omicron spread? It was fast in South Africa. In Britain it started out doubling every 2½ days or so, but sped up. I’ll show you the numbers from New York City – it’s hard to figure out while we are looking at super-steep increases with daily variation, but every three days seems about right.

Notice the pretty clear change in shape right around December 13 – 14. Four weeks later (potential start of the end of the surge) would be January 10. Two weeks later (potential end of surge) would be January 24.

The second graph is cases per 10,000 population – so new case rates instead of raw numbers. Notice how Staten Island is double the other boroughs while Delta was dominant. (Trumpies not vaccinating). But also notice how, when omicron arrives, Manhattan takes off. Why? Are more people there sick? How does that happen? Or are more people there being tested? How does THAT happen?

So what could happen?

Biggish (few hundred thousand cases) surge.
Huge (over a million cases) surge.

Some people are out sick or quarantining (non-health care) but with no real impact.
Enough people are out sick or quarantining (non-health care) that services are impacted – fire, sanitation slow downs, longer lines at supermarkets, schools combine classes due to teacher absence.
So many people are out sick or quarantining (non-health care) that there are some stores, supermarkets, schools, etc that are unable to operate.

Some people are out sick or quarantining (health care) but with no real impact.
Enough people are out sick or quarantining (health care) that services are impacted – some elective procedure are delayed. Lines get longer in doctors’ offices and hospitals.
So many people are out sick or quarantining (health care) that there are breakdowns in service.

A proportion of those sick require hospitalization, but the rate is so low that even with the biggish or huge surge, there is no problem with hospital beds.
A proportion of those sick require hospitalization, and beds start getting tight.
A proportion of those sick require hospitalization, and the rate is low, but the biggish or huge surge is so large that hospitals begin to get overwhelmed. Elective stuff is canceled. Staffing issues cause cancelation of things that should not be canceled.

Omicron is as mild as de Blasio hopes it is.
Omicron turns out to be not quite as mild as we hoped. Go back and recalculate the answers to all the previous questions.

The surge will last 4 weeks. (omicron reached New York City around December 7)
The surge will last 6 weeks.
The surge will last 8 weeks.

Options?

Hope that the less serious complications hit us. Brace for them. But let life continue as it has been going. Reduce quarantining requirements, so as to not let omicron disrupt us. This is the de Blasio plan.

Limited measures. Step up pressure on masks. Temporarily limit gatherings. Close schools where there is spread. Add vaccine mandates, and enforce the ones we have. Encourage vaccination of the unvaccinated, including children.

Aggressive mask, vaccine, distancing requirements. School closures while the wave passes over us.

And?

And we will see. I think the wave will be huge, not just big. I think that some services will be partially overwhelmed, and that only limited disruptions to health care will occur. I’d like a better handle on how bad the infections are before making more policy – but vaccine mandates for students, yes. And closing schools for a short while really would depend on the shape of the curve – it could be the right move – but I think we are short information just yet. If extending closure through January 10 would appreciably limit the spread, then I think we would want to go for it.