How would a character with a highly contagious virus be handled in game? Would there be something to stop or wildly slow the progression of the disease, or would the effects of the virus play out as they would naturally per their canon's rules? It's essentially a zombie-esque virus which, once it's active in the system, acts pretty quickly and thus far has no known cure in the world the character comes from.

If you need more info, I can happily provide it, I just figured I'd ask generally first, before getting into the dirty details!