Ah… I guess they should have called this Kansen 2.5 - I recognize these “new” people as support characters in Kansen 3.
On the global infection thing: I’ve thought it make more sense if the disease stayed in the geographical region (Japan, Korea, China) for quite awhile. Reason being, it’s transmitted through sexual contact and has a fast incubation. Someone gets screwed and in merely a few minutes they experience a change in their cognitive thinking (sex, sex, sex). In a couple of more minutes the infected person loses their moral reasoning and inhibitions. Before the first hour the vast majority then lose their sanity with an overwhelming urge to propagate the plague, spurred by their insatiable sexual desire. While some people can retain higher mental functions and complex thinking, that’s more the exception than the rule ¬ñ 99% of the infected can do nothing more than fuck and seek out more people to fuck. Even in the event higher thinking is kept, it’s tainted by sexual urges. Thus so far only humans and dogs appear to be carriers – and the virus isn’t airborne.
I honestly cannot see a plane making an international flight or voyage across the globe, if someone aboard is infected. That person will not be able to hold themselves together, and if the entire plane/ship gets infected, it would either crash/sink or be destroyed for unusual behavior (losing radio communication will get you shot down these days). Also the events of Kansen were aired in Japan only hours after the first infection. Other nations would have seen it happening¬Ö thus a massive quarantine of Japan and people leaving Japan: especially flights and ships. Post 9/11 they’ll just keep them on the plane, and if anyone runs out, they’ll get shot. Airports have a LOT of government armed personnel these days.
Of course it’s all fictional… so anything could happen.