Revising the Numbers

We are already at 4000 confirmed cases of the Wuhan coronavirus, and the death toll stands at 100. That's a doubling of cases in 36 hours, with a mortality rate steady at 10%. Again, it should be noted that the mortality rate must be calculated from the total number of cases that existed, or had existed, some 2 to 3 days ago. 100 dead out of a group of about 1000 cases is 10%.

However, the numbers cannot be trusted. There are good reasons to believe that the government is under-reporting the spread and severity of the disease. If they are clever about this, they may currently subtly overstate the doubling rate, so as to get closer to the real figures over time. Instead of an express revision, making them look bad, they choose to publish more aggressive spread rates for a week or two, so that when it's clear to everyone that the disease has reached epidemic levels, the official numbers match what is seen.

Going from 1000 official cases to 2000 cases took 36 hours. Going from 2000 to 4000 took likewise 36 hours. We can therefore expect 8000 cases to be reported late on Wednesday. By then, we'll probably have some data for the spread rate outside China, giving us a hint as to what the real numbers may be.

The rate of contagion will not be the same everywhere. Only densely populated areas will match the high rates seen in China. In places where people are less crammed together, the decease will spread slower.

By Robert Valette - Own work, CC BY-SA 4.0, Link