People are already beginning to talk a lot about virus mutation, in essence taking the view that the virus is one step ahead of us in our development of a vaccine. The inference is that with every successive mutation it becomes a more dangerous little chap, and we’re left chasing shadows.
I’m no virologist, let me make that clear. But I don’t think that’s the case. My recollection, from the limited amount of microbiology I have been exposed to, is that with time viruses become less pathogenic. Not always but in general.
Look at it from the virus’s point of view, if it had a point of view. The virus has only one purpose in life – to replicate and therefore spread. Any mutation that improves the chances of doing so is likely to be successful. And vice versa. So in terms of propagation of one’s genome, killing the host is not just rather ill mannered but also counter-productive.
You have to remember that being harmful to the host does not improve your chances, as a virus, of proliferating your genome. Actually a pretty bad idea. If a virus is particularly virulent and kills its host in too short a space of time, it actually reduces its reproductive capacity.
It’s a fine balance. The virus needs the host in order to replicate its genome. It’s best chances of doing that are by reducing its pathogenicity or by increasing its infectiousness during the presymptomatic stages in the host. The latter is perhaps more difficult to achieve so in general viruses become less virulent with time. Presumably mutations which cause less damage to the host allow more opportunities for virus transmission.
There are of course exceptions. The 1918 influenza pandemic was biphasic. The first phase, in the early months of 1918 killed many but the second phase in autumn killed twice as many.
There are no guarantees in virus mutation. Each is in essence a throw of the dice. But to mutate to a less pathogenic form makes the virus more successful in its own terms of replication. From a Darwinian perspective it makes sense for the virus to be less harmful. With time, less pathogenic forms will win out. So my message to the coronavirus is to try and be a little less antisocial. Play nice.
*If a proper virologist has time to skim through these ramblings, I would be very grateful. I don’t want to spread misinformation. Or sound like Donald Trump.