There's two scenarios: the international medical community fights it, with quarantines (current status), or they decide that the wall has been breached, wherein they switch to a focus on amelioration. You can't have it both widespread, spreading without control, and have quarantines, at the same time. There's no logic to quarantining something you can't stop. Instead, it becomes about minimizing disruption, minimizing spread within communities, and maximizing treatment.
As it stands, we're in the former situation. The latter is also a real possibility. But not both at the same time.