Durai is an interesting character that we never seem to quite know enough about, he is shadowy enough that there could have been some higher orders he was following.
Personally I don't buy into the new world order or families conspiracy since as far as I can tell I don't see the pieces there. that being said I'm sure enough of the pieces are there for us to suss out most of the story and I for one am still having trouble seeing the forest from the trees.

I just don't see the point for someone to unleash a global epidemic like this to implement a "new world order" as what is there left to reign over? Is there a super secret bunker full of monocle wearing Monopoly guys somewhere? What is their endgame, who will drive their fancy cars?