I'm holding out hope that once ebola blows over and comes to nothing they'll realize these people are full of it but I'm not holding my breath, cognitive dissonance is deep.
Unfortunately whatever happens is likely going to be shoehorned into the narrative. Like with the "chemtrails" thing. If the California drought continues, then chemtrails caused it. If it rains a lot this winter, then chemtrails made it rain.
The underlying belief is that everything is controlled. The details of what happens are just whatever the "elite" made happen, and so will confirm the belief.
The challenge here is making someone see that their belief is not obvious. It needs to be evidence based. They think they have all the evidence they need, but they really have no real evidence. It's quite a challenge to communicate this without the angry cries of "wake up sheeple!"