Earlier during the COVID apocalypse, I posted an essay about pandemics and viral evolution. In it, I identified some of the key characteristics of fitness for the survival of any novel virus. That essay is on FB rather than here on this blog. No matter. One of the points that I made was that a viral strain that is very contagious has a fitness advantage over other strains that are less so. I also pointed out that a virus that is rapidly lethal stands at a disadvantage. If you kill your host who has been making copies of you so that you can spread, you have brought your own line of production to a sudden end – your bad.
It is better to slowly sap your host’s resources in your service. The longer your host survives, the more hosts (s)he can recruit to make yet more copies of you – ensuring your immortality until either you have killed every potential host or your progeny have mutated into a form more fit than you.
From the perspective of evolutionary biology, and game theory as well, the most fit virus is the one that can ensure its own long-term survival. A virus that recruits hosts to replicate itself without killing those hosts always has the survival advantage over viruses that are lethal.
Enter Omicron and possibly subsequent variants of SARS-CoV-2. If these variants cause milder disease with a much lower death toll, they have a survival advantage over more lethal strains. This is good for the virus, and it is good for us – the hosts. It gives us time to develop natural immunity. We’ll have to see how this evolutionary competition plays out.
For those who “don’t believe in evolution,” this is not the blog you were looking for. Go find a blog about creationism, Pendejo!