The markets can’t predict the epidemiologic outcome of the coronavirus, they can only respond to economic decisions made by people.
The markets don’t CARE about the epidemiology of any disease.
They CARE about whether they will make money this quarter.
When whole supply chains are down because nobody is working (for whatever reason) the market reacts to this.
If china was in the middle of a civil war and the supply chains crashed it would be exactly the same thing.
No product, no sale. No sale, no profit.
It’s as simple as that.