Number of Confirmed Cases Doesn't Matter—Here's What Does
Hysterical headlines scream about the number of new coronavirus infections every hour. This is a mistake. Ignore those headlines. Number of confirmed cases will rise as number of people tested rises. If we tested everyone for the flu, the number of confirmed flu cases would be astronomical.
Doing some casual analysis, it’s pretty obvious what drives the death rate: the number of hospitalizations in a given geographic area.
Last week I pointed out that mean averages are meaningless, even destructive if used to project into the future. One of the reasons means are meaningless is that diseases do not spread in a linear fashion. The skip and hop like tornadoes.
Instead, I’ve tried to find the known variables that seem to relate to numbers of deaths. Then, look for a logical reason why this correlation might be meaningful.
As obvious as it sounds, using only the data that are readily available to the public, the strongest logical correlative to deaths is serious cases, not number of infections.
You might think, “yeah, but the more infections, the more serious cases.” Smart assertion, but the correlation between infections and serious cases is much weaker than between serious cases and deaths. Some countries with many, many cases, like Germany with almost 30,000, have very few serious cases, like Germany with 23. That’s 0.0008. Low.
Then look at Italy. 63,927 cases and 3,204 serious ones. And those are mostly in a small geographic area. That overwhelms the healthcare system, and overwhelmed healthcare systems result in more deaths.
In the United States, we had 42,000 confirmed cases out of 330,000,000 people as of March 23, but we have 1,040 serious cases. Even 1,040 serious cases is meaningless until we know where those cases are. If they’re all in New York City, New York City is going to have problems. Not just with coronavirus, but with everything health related. If the ER is overwhelmed, your broken arm or car crash injuries or heart attack will receive worse care than if the staff is fresh and healthy and underworked. But if 1,040 serious cases are distributed evenly around the country, it isn’t a blip on the healthcare radar.
The question isn’t “how many infections,” it’s “how many need to be hospitalized, and where?”
But there’s another reason why number of infections is meaningless: testing.
Everyday, more people get tested than were tested the day before. Therefore, every day the number of cases will increase more than the day before. It looks like this:
Day Tested Positive RunningTotal 1 100 10 10 2 120 12 22 3 150 15 37 4 200 20 57 5 500 50 107
You get the point.
Is the number of cases going up? Sure, but probably not as fast as the number of confirmed cases. Testing is exposing confirmed cases, and testing is accelerating. Or maybe the number of cases is growing faster than the number of confirmed cases. We don’t know.
But when we don’t know, we probably shouldn’t publish terrifying headlines like: “New York Governor Issues Dire Warning as Coronavirus Rates Rise Faster Than Expected.”
Faster than who expected? The positive rate in New York is pretty steady at 10 percent. Therefore, anyone with a 5th grade math level would exect the case rate to rise or fall with the number of tests. More tests, more cases. Fewer tests, fewer cases.
And there’s more. The media are reporting that 80 percent of cases are not serious. That’s true across the globe. In the United States, though, 96.5 percent of cases are not serious using the formula (deaths + serious)/cases. And only the serious cases put a strain on the healthcare system.
If the media were sincerely concerned about this disease, they wouldn’t publish so many misleading stories and headlines designed to terrify people. But the media aren’t sincere. They’re sensational. The media want two things:
Lots of deaths.
So they try to make people think things are worse than they are, and that’s cruel, especially considering that things could get a lot worse.
When you hear hysterical pronouncements about rises in confirmed cases, remember that 96.5 of those cases are not serious. The 3.5 percent that are serious are very serious and deserve our prayers and sympathy. But lying about the numbers engenders fear and selfishness, not compassion.
Pray for a quick end to this pestilence and an even quicker return of the greatest economy in US history. Pray, also, that our reporters and headline writers stop sensationalizing a bad situation for financial and political gain.
If you’d like to do your own analysis, the complete dataset is available here.
Note: all number are as of 13:00 CDT Monday, March 23, 2020