Diseases, viruses do evolve, like any living organism. There's no argument there. What that means is, there could be various strains over time. For those that don't know, it's called, "Gaiea's Hypothesis'. White man pushes for discovery, they introduce 'new' strains of diseases and viruses to the indigenous people. It's in history. It's common sense too.
But all this, 'man created' virus or disease is absurd to me. Although, I cannot disagree that there is a potential for conspiracies, because GOV'T has tested many things on humans. Go look up WW2. Amphetamies were distributed to soldiers in WW2. etc. The connection is there. I must agree tho, that biological warefare is 'serious' and 'scary'.