I think we are learning new things about respiratory viruses with this one. For example, I dont think there was ever a respiratory virus that people were being tested so much like this one.

Like DZEC said, the virus seems to be able to replicate in the mucosa in some people but not penetrate deeper. Like the typhoid where the reservoir is in the gallblader/billiary tree. Is that actually a malfunction of the immune system? Should our immune system be able to wipe the virus from the mucosa as well?