Economically so far Ebola will have minimum effect on the World Economy, but for the economies involved, absolutely shattered and destroyed and politically could end the same as well as is already happening, commerce has virtually ceased, cross border trade between the three nations has ground to a halt, farmers either are dead or can't move their goods so a hunger crisis is looming.
Really terrible stuff.
But again their economies were so small to begin with, it's crass to say but besides aid costs after we can curtail this crisis, it's a blip on the world economic radar.
The real economic consequences will be if it reaches Asia or India in any significant way, if you affect travel, commerce and tourism out of those places, that's when we'll start to see a significant global economic problem.
Oh and the swiftest global medical response in human history... because money.
You're right about one thing, let this hit countries hard with big GDP's like the US, Asia and India and you'll see a massive response with resources, funds and medical teams.
Einstein, "science without religion is lame, religion without science is blind."