steampunk heart

“New daily cases” and the second wave

All the media have banners and counters and big red numbers of the front page. They proclaim the “new daily cases”.

For example, today, it was reported that Spain has 22,000 new cases, Italy has 37,000, the UK 24,000 and the US 116,000. They are ubiquitously called “new daily cases”.

It wasn’t until I was working on my rebuttal of Moon of Alabama that I realised so many people take this statement literally. They shouldn’t, it is incorrect in almost every respect. To be clear here – “new daily cases” are probably not new, they certainly didn’t all happen in one day and they definitely aren’t “cases”.

Let’s start with the word “new” – They are almost certainly not “new cases”. Today isn’t the day they got infected, today is the day their test results came back. The may have been infected a week ago, or a month, or 6 months.(Or, indeed, never).

Just because Person A got tested on Monday, and Person B on a Tuesday does not mean B is a newer case than A.

We don’t have any idea if more people are getting infected, we only know we are testing more.

Charting them as “new” means you can make the scary red line go up, but that is mathematically incorrect, and intellectually dishonest.

Secondly, the vast majority of “cases” reported are not actually “cases”.

Classically speaking, a “case” of a disease is someone who displays symptoms. There is a huge difference between being infected, and being a “case”. That’s why infection fatality rate (IFR) and case fatality rate (CFR) are two different numbers.

However for COVID19 they have abandoned this distinction, referring to every single positive test as a “case”, despite the fact the vast majority never exhibit any symptoms.


The “new daily cases” are none of the above. The “second wave” is likely the result of increased testing. The more people you test, the more “infections” you will find, (especially when your test has a known risk of false positives).

If you increase the number of tests you run, you will increase the number of infections you find. That is not a disease spreading.

In the spring the UK was testing 10,000s of people per day. As of last week, they claim to be testing half a million. From estimated false positive rates alone, that’s between 4000 and 20,000 “new cases” per day.

An analogy:

If you move a piece of furniture in your living room and find a spider underneath it on Saturday, and then the next day you move twenty items of furniture, and find 10 spiders it would be absolutely crazy to say there was 900% daily increase in spiders or that spiders are “increasing exponentially”.

Those spiders were probably there yesterday. You just weren’t looking for them.

…and if you hadn’t gone out of your way to find them, would you ever have known they were even there?