I recall somewhere that someone said the plague does affect some wildlife. Wolves, I think, so probably all canids. Since it's spread relatively slowly and hasn't popped up in multiple places, it probably doesn't affect any migratory animals, like birds, or hitchhikers such as rats or other vermin.

We know from Torq that an infected person develops a gray pallor. Other symptoms include physical weakness, perhaps a reduced constitution.

We also know that the aboriginal people of southeast Ansium seem to have some degree of immunity, which raises the possibility of a vaccine of some kind if whatever protection they possess can be isolated and reproduced. The epicenter at the moment seems to be somewhere in the vicinity of Lake Medre in the Tawaren Basin.

Torq's description of the Grey Watch also implies that there is some kind of dark presence manifesting in Tawaren, turning previously loyal Groamen against their countrymen. The plague does not produce significant quantities of undead, though the significance of the Grey Watch's change of allegiance has not yet been explored that I am aware of.