As well as it being very contagious, as well as people apparently not developing immunity and catching it a second time, often with heart failure. Oh, there’s that whole cytokine storm thing, which most flus don’t have (and the killer Spanish flu did). Then that it apparently can survive hot weather, such as in Singapore and the Middle East.
No, we really don’t know enough yet about it and what’s going on.
I think this has to yet be determined for COVID-19.