"make it more easily transmissible _or_more_pathogenic_"
You probably should be more concerned about the flu or the common cold becoming lethal than about Ebola becoming airborne. Reason? There are way more throws of the mutation dice for the common cold and flu than for Ebola because these are way more common.
Something like the Spanish Flu returning scares the living shit out of me (while I also know it's remote), that fucker does mutate, it is airborne and it has happened and that was in a world with slow transport.
That said I'm still more likely to die from Heart Disease or Cancer, statistics ftw.
You probably should be more concerned about the flu or the common cold becoming lethal than about Ebola becoming airborne. Reason? There are way more throws of the mutation dice for the common cold and flu than for Ebola because these are way more common.