Posted on 03/18/2022 2:07:16 PM PDT by Jan_Sobieski
It is understood that viruses evolve over time to become less lethal because more lethal viruses don't get as many chances to spread, so the evolutionary pressure is for viruses to mutate until they become less dangerous.
For viruses with low case fatality rates, and even if one takes the US' current resolved cases fatality rate of nearly 2% as the metric*, 2%, occurring mostly in the elderly, is low. It is insufficient to create much in the way of evolutionary pressure. So, while the trend over decades or more is usually downward, it can be erratic, with spikes upward that exceed the lethality of the original variant. All it takes is a mutation or set of mutations that gains both lethality and transmissibility. That is in fact what happened with Delta. If the increase in contagiousness exceeds the increase in lethality, the virus has "improved" itself and the new variant will dominate cases, until herd immunity to it occurs, or a newer yet variant with an advantage pops up.
*Since many people with asymptomatic or very mild cases never got tested, that nearly 2% RCFR (Resolved Case Fatality Rate) figure is almost certainly high. CDC case estimates would indicate it's 1% or less.
Lethality WITHIN a variant does tend to decrease with time, but that's due to better immunities, treatments, and a reduced pool of the vulnerable if the virus kills faster than that pool is replenished.
What I find interesting is that even here on FR, more and more reports of repeat cases of COVID are evident. This doesn't surprise ME -- I've since early on maintained that at best we'd likely have a situation where with time, "immunity", either from vaccines, or cases, would not likely be any better than what we see with flu, and probably would be poorer.
Being equally idiotic is nothing to brag about.
When I first heard of the virus, I knew it could not be stopped and it would eventually move through every aspect of the population of the world.
My mother is old and I was going to protect her from it.
We live in the country and my mother lives in a house a short distance away on the same property. I have little contact with the general public and she only has contact with members of the family.
We reduced our contact with the public as much as possible and we managed to avoid the virus for a year. When it came, I forbid everyone from going into her house or having any contact with her until we all recovered.
We stayed away for longer than 14 days while us younger folk dealt with the virus.
Now we are all immunized and she hasn't caught it at all, and very likely will never catch it.
*THAT* is what should have been done with the old folk. They should have been kept isolated from people who had not already had the virus until they were surrounded by immunized people.
+1.
You pry had the Alpha strain, the original one. Delta started after the vaccine was released.
Probably. I had it before the vaccine came out in December, and after you already had it, why bother getting the vaccine?
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