You say we do not know, and they're not telling, yet you apparently know enough to say I don't know what I'm talking about?
I could say the same about you, but I am far too polite.
If this is true:
1. 'normal' Covid confers immunity to the S.African variant, and
2. the AZ vaccine does not, and
3. the AZ vaccine confers immunity to 'normal' Covid, as it may,
then isn't the AZ vaccine artificially selecting for the S. African variant?
It certainly doesnt mean *less* lethality which is what you claimed repeatedly. It could be positive, negative or neutral.
I should not have to teach you this: Of course the prevailing pressure is lower lethality, since dead hosts are in the equivalent of a permanent lockdown, they certainly can't go about infecting others. A mutation could drive toward -ve, +ve or do nothing to lethality, but only the first confers any advantage over the status quo,hence only the first, to lower lethality, is a driving factor in selection.
It certainly doesnt mean *less* lethality which is what you claimed repeatedly. It could be positive, negative or neutral.
Of course the prevailing pressure is lower lethality, since dead hosts are in the equivalent of a permanent lockdown, they certainly can't go about infecting others.
Fon you're missing the point of Splatt's (correct) reasoning here. The driving pressure on evolution is reproductive success within the given environment. Any mutation which confers an advantage here will tend to be preferentially selected. So if the ability of a virus to transmit is environmentally compromised (say by lockdown) then a mutation which is more lethal yet confers greater transmissibility could be a more successful reproductive strategy than simply lowering lethality. In fact simply lowering lethality, where transmissibility has been environmentally compromised, may offer little to no selective advantage - especially in the case of a virus, like covid, which does not have a particularly high mortality rate for its hosts.
By your logic every disease in history would spend all its time getting more and more transmissible as time goes on and quite clearly that doesnt happen.
Of course every disease in history does spend its time attempting to get more and more transmissible. It does not happen because there is a limited number of changes to improve transmissibility. You could say it trends towards max transmissibility, which may be an absolute or local limit. And in parallel, similar selection forces apply to reduce lethality, where conflicts arise, the total practical value of both properties is the driving factor, you can call it natural annealing, which is what nature is.
You have used the exact same argument yourself,over and over again, by saying lockdowns, which constrain scope for transmission, drive the virus to increased transmissibility, I refuted that argument by saying the virus can not mutate to ride on the deutschlandrundfunk carrier wave! You are inadvertently destroying your own arguments against lockdown here !!
In principle lethality and transmissibility are orthogonal properties, but since the structure and functionality of the virus are so basic, they are intertwined, individual mutations might easily effect both properties, for better or for worse, or one for the better the other for the worse wrt the prospects of the virus, not in human terms. But, leaving aside the practicalities, in theory, lethality and transmissibility are orthogonal properties,but in the real world they interact via the structure of the virus.
