Quote:
Originally Posted by kinetic
We were discussing this at work the other day. As we were all 'tradies'
I guess we were unqualified to ponder such huge concepts as viral
research  , but in a nutshell our conversation and logic was this:
Humans have been on the earth for many millions of years.
Over this time frame virii (sp?) and bacteria have also had a chance
to evolve/ mutate.
In that time frame wouldn't a virus mutate a strain to wipe us out
as a species? 100 % mortality?
Why, in just a small comparative window of decades does another
strain of some virus appear that, if not for just that slight missing
factor, be that killer virus?
Steve |
Viruses usually don't kill a host unless they cause an overwhelming immune response (or overwhelm the immune system) or do too much damage to the cells they're invading and/or the byproducts of that invasion become dangerous. Viruses (and bacteria as well) reproduce in huge numbers and very quickly, so any mutations in their genes or viral DNA can occur very frequently and be passed on rapidly. Consequently, they can evolve rather more quickly than most living organisms. A virus could evolve that was 100% fatal, but it would be defeating its own purpose of survival and reproduction if it did. Something like that would be more than likely man made. A weapon. A one off agent used to kill a portion of a population, or to kill it completely.
In nature, there have been nasty viruses and bacteria that have caused huge numbers of casualties, e.g. the Black Plague, Spanish Flu, but there's always been some who have been immune to the attacks. That immunity then gets passed onto further generations. But sometimes, that doesn't work as well as it should.