As people have noted, "Africa" is not a single, uniform place, and contrary to your perception, none of these places have had an outbreak of Ebola, and Ebola is

As people have noted, "Africa" is not a single, uniform place, and contrary to your perception, none of these places have had an outbreak of Ebola, and Ebola is a rare enough disease that there really isn't institutional knowledge. Western doctors handling outbreaks screw up with some degree of frequency - the simple volume of cases they're dealing with, combined with some low but non-zero chance of error means that infections like this are inevitable. Rather than elaborate speculation about the virus mutating to an entirely new transmission path (with new cellular receptors, a built in way of dealing with mucosal immunity, a capsid capable of being suspended and transmitted in droplets, etc.) a much more reasonable explanation is this: Humans screw up. Doctors are humans. Ergo, Doctors screw up.