Terms searched: Infectious diseases, chicken pox, fatal diseases, SARS, immunization, transmission of diseases
I have three characters (all male and over 70), and for the purpose of the story two of them should be infected with a fatal disease by the third. What I'm looking for is an infectious disease that would be carried by the third character, but the third character should be immune to the disease himself. (At the time the story is set, medical help has been completely unavailable for at least several decades) I considered chicken pox, but it doesn't fit the story, and I would prefer to stay away from all similar diseases (smallpox, ...). SARS fits symptom-wise, but I could find no info on the possibility of acquiring immunity without vaccines.
(For personal reasons, I would like to stay away from tuberculosis if at all possible)