If you have actually been tracking the spread of the COVID-19 pandemic all over the world, as we have, you’ve doubtless seen a great deal of data. The raw numbers look shocking, and in a lot of cases they are, however as always it’s most importantly important to ask yourself what the numbers suggest.
For instance, our own Tom Nardi created a counter that displays the overall variety of COVID-19 cases in the United States. It’s a cool project that puts together some web-scraping, a good OLED screen, and a 3D-printed network screen. When this is all over, it can be quickly re-trained to reveal some other statistic of interest, and it’s a fantastic intro to a variety of web APIs. However, it’s taking a look at the wrong number.
Let me discuss. Diseases spread greatly: the more individuals who have it, the more people are spreading out it. And rapid curves all look theexact same when you plot out their instantaneous values– the raw variety of COVID-19 cases. Rather, what differentiates one exponential from another is the growth specification, and this
relates to the number of brand-new cases daily, or more properly, to the everyday change in brand-new cases. If left unchecked, and especially in the early phases of spread, the number of brand-new cases grows every day. However as control efforts, primarily social distancing, take effect, the rate at which the variety of brand-new cases can slow, or perhaps go unfavorable. That’s the plan, anyhow. As is effectively discussed by this video from 3 Blue, 1 Brown, if this were a naturally spreading epidemic, the point at which the new cases just begins to decrease marks the middle in the course of the disease. Here, we’re hoping that particularly stringent quarantining procedures will cut this run even much shorter, however if you’re interested in how the illness is spreading out, the point when daily new infections turns around is what you’re searching for.
Why not put the everyday distinction in new cases on your desktop, then? These numbers are loud, and the difference jumps all around. To be severe, you would probably wish to put a moving average on the brand-new cases figure, and look at that difference. Or simply show the new cases rather and look for it to drop for a couple of days in a row.
Still, this won’t be a perfect procedure. For starters, COVID-19 appears to incubate for roughly a week without symptoms. This suggests that whatever numbers we have, they’re most likely a week behind the actual circumstance. We will not see the effects of social distancing for at least a week, and maybe more. More making complex things is the accessibility of tests, human aspects like weekends when more people get evaluated however less government reporting offices are open, timezones, etc. (What happened on Feb. 13?)
I’m not going to go so far as to say that the COVID-19 stats that we see are useless– really vice versa. But if you’re going to armchair quarterback this pandemic, do it right. Plot out the daily new cases, possibly use a little smoothing, a minimum of in your head, and recognize that whatever you’re seeing now most likely represents what occurred recently.
When you finally see the turning point, you may celebrate a little, since that indicates the middle was a week back. We’ve seen it happen in China around Feb 2, and I’m anticipating it happening here. I hope it occurs anywhere you are, and soon.
We will survive this. Stay safe, all. And keep yourself uninfected to keep others uninfected.