Why nobody asks about the other 18 Coronavirus strains is beyond me.
The '-19' is a designation for 2019 the year it was first observed. There are a lot more strains than that. They think they have found two variants of this wuflu, one seemed to be more prevalent in the West Coast USA the other East Coast USA, possibly Boston, with BioGen Employees.
Viruses evolve. When they become less contagious or less harmful they just 'go away' and no one knows why. Seriously. They don't know why.
The '-19' is a designation for 2019 the year it was first observed. There are a lot more strains than that. They think they have found two variants of this wuflu, one seemed to be more prevalent in the West Coast USA the other East Coast USA, possibly Boston, with BioGen Employees.
Viruses evolve. When they become less contagious or less harmful they just 'go away' and no one knows why. Seriously. They don't know why.
The -19 is for the year of discovery (2019) not the number of F coronaviruses