Ammm....I think that its sad to see how the world and species (microorganisms) like bacterias that mutate....I am not sure but I think that it is because the world and nature are suffering big damage changes so it affects until microorganisms, if someone create the world it would be perfect until humans accelerate or stop natural processes, but most of the shown pandemics are of long time ago so I don´t have an answer to that...aaammm!...the pandemic that impressed me the most was the last one because it killed like one billion people and it was because the war, I think that if someone do something bad that affect to the people it will have BAD impact.
We dont need of these sickness and multi-deads!.
aaammmm!