One of the most important concepts to grasp in order to gain an understanding of mutating
airborne disease is the concept of a Virus-Year.
We do a similar comparison with cat-years or dog-years, and the simplified way that it works is this:
if we live 100 years, and they live 20 years, we divide 100 by 20 to get approximately 5 cat-years
or dog-years equivalent to one year of our lives.
Just as cat-years or dog-years give a relative number that makes it easier for us to understand their age,
a Virus-Year gives a relative number to provide better understanding of the life cycle of a virus.
For instance, one Coronavirus virion in one cell takes 6 hours to fully produce a new generation of virus variants.
The virion's life ends with the completion of it reproducing, but the important comparison for understanding their
evolution versus ours is the production of that new generation.
Humans take approximately 20 years to produce a generation, so you can say that 6 hours is 20 Virus-Years,
or a Virus-Year every 18 minutes.
It then follows that 30 hours in one host can represent 5 generations of virus, or a Virus-Century -
the amount of evolution that it would take humans 100 years to accomplish.
Once you understand this concept, you can begin to understand why we have ever had a normal cold-or-flu season:
no matter how deadly a source Coronavirus, Rhinovirus, or Influenza virus may be,
with a large number of interacting hosts, we can easily create chains of evolution of that virus that
within days can span hundreds of thousands of Virus-Years of evolution - a virus that would no longer
be able to resemble that source virus that it evolved from.
That interaction has been our secret weapon in fighting cold-and-flu for millions of years, and
it is not only relied on by us, but also by the viruses themselves - viruses need to not be overly deadly,
or they would have gone long extinct after killing all of their possible hosts -
viruses want to be less deadly so we will still be there for them,
and they want to work with us to be less deadly.
Using our differing lifespans as a tool, we make cold-and-flu less deadly every year, including this past year with Covid-19.
