06-17-2021, 02:46 PM
Well, the RNA dependent RNA polymerase that replicates the Covid-19 genome gets it right 9999 times out of 10,000 which means that in an average replication, there are 3 mutations on the average (most probably neutral) and in an average human case there will be something like billions or trillions of new copies of the virus. This presumably means that every single nucleotide in the viral genome gets changed at least once as it goes through any human with severe illness. Some runs of nucleotides get changed. There is also evidence for a kind of strand switching in which one viral genome ends up mixed with another. So there is a lot of mixing and switching and mutating going on. Probably the only thing protecting us from an immediate super virus is that there is only so much that this one little genome can do and, in addition, the virus particles that escape a sick individual to infect someone else are going to be the ones that replicate effectively and find their way into exhaled vapors and cough particles. Mutations that damage these processes will be lethal to the virus. On the other hand, a mutation which works a little more efficiently in a particular population will get the edge when there are thousands of new cases.