Coronavirus and Influenza are different types of virus.
The nCov virus is new and even though we are trying, we do not yet know what it's capable of and it's too early to come up with solid statistics about the spread and mortality. There's also concerns that Chinese authorities are not sharing the real numbers.
At present we are told that 40,655 are infected with 910 deaths and 3669 recovered.
Apparently 6,495 cases (18%) are serious/critical. This number is worrying were there to be mass spread in the UK, given the current state of our NHS.
If you consider that 3,669 have recovered and 910 have died, thats 20% of cases that have resulted in death.
This doesn't take into account the people who are currently infected in a mild condition (82%), as we don't know what will happen to them. Do they go on to recover, or do they then go on to become critical and pass away. Some people die upto a month after becoming ill. On the other hand it's possible that many more thousands have been infected and not tested, and then survived, which would also completely change the stats. Basically we just don't know at the moment. Given that we now have infections in the West, we should be able to get reliable data about how dangerous, or not dangerous it is.
There is also a discrepancy about the rate of spread, and how it is spread, with some estimating 1 person infecting 2-3, but now we are seeing what's happened with the British super spreader.
I'm relatively young, so have not lived through many disease outbreaks, but as others have said the reaction from the government does make you wonder, and I have not seen a reaction like this before.