|
|
|
|
|
by mint2
1655 days ago
|
|
The reason it’s eradicated is entirely due to vaccinations and the unique fact it had no animal reservoirs. Prior to that, it was both very deadly and very contagious. Those facts were not hurting it. Those attributes did not make it evolutionarily weak unless you count motivating people to make vaccines. What is your point? |
|
In other words, the high-level theory is that more severe viruses either kill their hosts, or make them so sick that they stop interacting with other potential hosts. A form of social distancing, if you will.
In both cases, the virus is triggering some form of behavior change in its host that reduces its reproduction, providing evolutionary pressure towards milder viruses.
One could argue that the development and wide distribution of a vaccine is just one form of host behavior change, and should be factored in.