If it hit Israel, the Israelis would be much more capable of dealing with it than the Palestinians, and it just might wipe out the Palestinian population. Islamic terrorists just might score an own-goal with something like this. Of course, they can always blame it on the Mossad.
While this true, it really would not be big of a problem here in the US, Europe, or Israel at all. I would estimate the the dz would do very minimal damage to any industrialized country, even those without access to vaccine who quarantine properly. You're only infective once the fever starts, and most people at this point are in such bad shape, so quickly, they'll be at a medical facility, not at the mall spreading the virus.