Despite brainstorming for a couple of hours, all of them could only come up with two scenarios to answer Alucard's question. One, the undead were slowly evolving and hence were gaining some sort of resistance or immunity to salt, which would explain how the undead crossed the ocean.
And second, the undead had infiltrated the other continents. None of them wanted this to be true, but no one could ignore the possibility either.
This conclusion was a bit unsettling due to obvious reasons. There were undead creatures walking in their midst and no one knew about it. Something like that wouldn't have affected the werewolves much, but for the vampires, the undead's presence was nothing short of a pandemic.
Not to mention it was a direct violation of the treaty between the species which stated no species is allowed to step foot into the land belonging to other species until and unless they are invited to do so.