You are right that regular flu kills far more people each year. From what I can tell, there is no exact number because different groups use different criteria for their counts. But the average seems to be 12,000 to 56,000 die each year from the flu, just in the US.

Back to China, part of the craziness is due to the nature of the cities there. First, Wuhan is only the sixth largest city in China but it is bigger than every single US city. That’s a lot of people crammed together and that makes it easier for something like this to spread.

The other part, from my experience, is that some antiquated culture aspects combined with some extreme poverty in China make for a prime virus spreading ground. And that is why it won’t have the same impact globally.

But if we ever do see a deadly superbug that spreads globally then we are toast with how easy it is for people to travel quickly.