How is covid 19 novel exactly? I get that it is a new strand but dont new strands of viruses come out all the time?
So first off taxonomy is a crapshoot because nature doesn't fit into clean human definitions, the issue with viral taxonomy is they are less complex and evolve exponentially faster than species further up the complexity ladder.
This is a known species, basically its the same species as SARS (CoV1) and hundreds of other bat-specific strains.
This is a new "strain" where in viral taxonomy strain is used as a stand-in for subspecies (or more accurately but less technically "breed"). What is known is that it is closer to several of bat-specific strains than it is to SARS (CoV1), and then at the species level the group is collectively sister to dozens of bat-specific betacoronavirus species and the "common colds" OC43 and HKU1.
The
virus is novel because (supposedly) its never been recorded/studied until now (assuming the ChiComs are stupid, rather than liars).
The
disease is novel because humans have never had an outbreak of this specific strain.
Now lets say something well-known, for example Ranavirus FV3 suddenly made the jump from froggies to human hosts. It would still be a novel disease despite being a well-studied virus, in part because while we know what it does to frogs and toads, we don't know what it does to human tissue.
Now all this being said, COVID-19 a.k.a. SARS-nCov-2 is actually pretty fucking tame when you realize its the same species as the OG SARS which had like a 10% lethality rate, and sharing a common ancestor with the "common cold" OC43 which is actually known for murking babies.
