I'm looking for ideas for a highly contagious airborne biological weapon (virus, bacteria, other) that would kill its host in a matter of days to a week or so, but that, once all infected hosts are dead, would become inert after a while (perhaps a couple months) so that the air and the corpses no longer can spread the thing.
Details not required really, just is such a thing feasible/believable? Would it be called a virus or some other term?