[nudephil (OP)]

We got this question from listener Andrea:

Why is the whole world so obsessed with the infection rate of the coronavirus? Surely a high infection rate and a low death rate is a good thing for humans. Seeing more and more people getting infected and less and less dying must surely be a positive thing. Yet massive decisions are being made based on the infection rates still...

Any answers?

[alancalverd]

If nothing changes, everyone will eventually be infected: the infection rate just tells you how long it will take to achieve 100% infection.

 The rate of serious complication requiring hospitalisation remains around 20% and the death rate, around 5%.

If you think these statistics are a Good Thing, please name the member of your immediate family you wish to see hospitalised and permanently disabled, and the member of your extended family (aunts, uncles, nieces, nephews, inlaws....) you want to die prematurely. If not yours, why mine?

[Bored chemist]

If the death (and lasting injury/ ill health) rate was zero then a high infection rate would be good.
But it's not.

Even with the best treatment some folk die. That's an intrinsic characteristic of the virus; we can't change it much.
But we can change the infection rate.
If everybody stayed at home then the infection rate would nosedive after a week or two.

Since the number of dead people is proportional to the product of the mortality rate (which we can't change) and the infection rate (which we can change) it makes perfect sense to talk about the infection rate.