https://www.rt.com/op-ed/500000-covid19-math-mistake-panic/

Which fatality rate, did you say?

First, there’s the Infection Fatality Rate (IFR). This is the total number of people who are infected by a disease and the number of them who die. This figure includes those who have no symptoms at all, or only very mild symptoms – those who stayed at home, coughed a bit and watched Outbreak.

Then there’s the Case Fatality Rate (CFR). This is the number of people suffering serious symptoms, who are probably ill enough to be in hospital. Clearly, people who are seriously ill – the “cases” – are going to have a higher mortality rate than those who are infected, many of whom don’t have symptoms. Put simply – all cases are infections, but not all infections are cases.

Which means that the CFR will always be far higher than the IFR. With influenza, the CFR is around ten times as high as the IFR. Covid seems to have a similar proportion.

Now, clearly, you do not want to get these figures mixed up. By doing so you would either wildly overestimate, or wildly underestimate, the impact of Covid. But mix these figures up, they did.

The error started in America, but didn’t end there. In healthcare, the US is very much the dog that wags the tail. The figures they come up with are used globally.

On February 28, 2020, an editorial was released by the National Institute of Allergy and Infectious Diseases and the Centers for Disease Control and Prevention (CDC). Published in the New England Journal of Medicine, the editorial stated: “… the overall clinical consequences of Covid-19 may ultimately be more akin to those of a severe seasonal influenza.”

They added that influenza has a CFR of approximately 0.1 percent. One person in a thousand who gets it badly, dies.

But that quoted CFR for influenza was ten times too low – they meant to say the IFR, the Infection Fatality Rate, for influenza was 0.1 percent. This was their fatal – quite literally – mistake.

The mistake was compounded. On March 11, the same experts testified to Congress, stating that Covid’s CFR was likely to be about one percent, so one person dying from a hundred who fell seriously ill. Which, as time has passed, has proved to be pretty accurate.

At this meeting, they compared the likely impact of Covid to flu. But they used the wrong CFR for influenza, the one stated in the previous NEJM editorial. 0.1 percent, or one in a thousand. The one that was ten times too low.

Flu toll 1,000 – Covid toll 10,000

So, they matched up the one percent CFR of Covid with the incorrect 0.1 percent CFR of flu. Suddenly, Covid was going to be ten times as deadly.

If influenza killed 50, Covid was going to kill 500. If influenza killed a million, Covid was going to get 10 million. No wonder Congress, then the world, panicked. Because they were told Covid was going to be ten times worse than influenza. They could see three million deaths in the US alone, and 70 million around the world.

I don’t expect you or I to get this sort of thing right. But I bloody well expect the experts to do so. They didn’t. They got their IFR and CFR mixed up and multiplied the likely impact of Covid by a factor of ten.