Winter is coming - What can we do to stem the spread of COVID?


I love this infographic. It's great for showing where the growth in case counts is coming from, but it's a linear scale. That means we really only see the growth where the level is already high, and it hides the growth that's happening in most states.

You look at this and think "It's mostly the green states that are having a problem".

It's more accurate to say "The green states are hitting crisis level first".


This is brilliant. Every state on a log scale, which lets us see the percentage rate of growth or decline...and it is all growth, everywhere. Ignore the occasional 7-day spikes caused by a backlog report (like TX in late Sep near the top right).

This shows that since mid September, most states have been seeing exponential growth.

"Exponential growth" doesn't mean rapid growth. It does mean it's a snowball effect, and although many of the snowballs aren't that big yet, they're all growing and are on their way toward a crisis.

The timing (mid September) suggests a change around September 1, visible after a delay for incubation, testing and reporting. IMO it's very likely this is tied to school and university reopenings, which added a lot of daily contacts for a lot of households, and the fact that we didn't do anything to offset that additional exposure. (I don't think the cold weather effect has had enough time to show on most of these charts.)

The take-home message here is that while states in the midwest are in or about to enter crisis levels, most of the country, including the northeast, has been on this train for 8 weeks now, and they're all heading to the same destination.


This chart is a bit geeky, but contains important information. I've added a bold red line for Rt = 1.0, that's the level at which each state is keeping a continuous, steady rate of infection.

Look back at mid April, when almost all states were bringing their numbers down. Look at May, as reopenings started. By the start of June, many states had gone too far, too soon, and our "second wave" happened.

For most of July and August, most states were doing well most of the time.

In early September, pretty much everybody started creeping up. Remember, being above the line doesn't mean you have a huge outbreak. It means your outbreak is getting bigger and bigger every week, however large or small it was at the start.

By the start of October, almost all states were seeing continuously rising rates of infection, and we still are. (This chart is current, but we can only infer what was happening with infections until about October 25, because of incubation and testing delays.)

The key message here is that while we tend to wait until it's a full-blown crisis before changing behavior, every state SHOULD be doing something now to get under 1.0, because the longer we wait the more severe, disruptive and expensive the reaction will need to be.


This is also pretty geeky, but makes another important point.

It compares how out of control the spread was in each state in mid October, to the rate at the end of the month.

Since this plot starts at 1.0, every one of these states had a growing epidemic at both times. But states above the dotted line were actually having the growth rate increases, i.e. and acceleration in the acceleration of case counts.

And here's the thing. We're not doing much to change the growth.

Cold weather is coming.

Holidays are coming, with travel, and extended indoor exposure to people outside our households.

All these things are going to further increase the rate that the wave is rising.

Every single sign I see is pointing to this winter's outbreak as a full-on disaster. We will not be getting federal leadership, I can only hope that some states take action in the mean time.

For individuals - remember that whether or not you are concerned about getting sick, you can become part of a chain that kills multiple people who are doing their best to avoid this.

If you have symptoms, isolate immediately and get tested.

If you're positive, isolate, have your household quarantine for two weeks, alert anyone you'd been in contact with over the previous week or 10 days, and work with your local contact tracing teams, if any.

If you've had close contact with an infected person, quarantine yourself for two weeks. (Not your whole household, unless they were also exposed.) These simple steps, done well, can make a huge difference. We're not doing well, and that causes chains like we're seeing in the White House.

Beyond test/isolate/quarantine, avoid indoor settings with people outside your household whenever you can. You may have to work in person, but avoid indoor restaurants, bars, churches and gyms. It may not be much of a risk to you personally, but it's a risk of further expanding the epidemic and unintentionally killing people in the chain you extend.

Seriously, seriously consider cancelling in-person holiday events with the extended family if you possible can. I get that many people can't handle that, but give it some consideration, and scale back or modify or eliminate those plans if you can.

Winter is coming. We are not ready. Do what you can to help.

Comments 0