The biggest risk it poses is getting into mega-cities like Lagos.
17-21 million people (depending on whose population estimates you believe) living in very close proximity, poorly equipped health systems and lack of public education on how to contain it.
The disease itself is not really a first world threat - the economic flow-on effects may be.
The current hysteria in the US is laughable.
Ebola is it's own worst enemy - it is so lethal, and transmission via bodily fluids is not as effective as via aerosol.