but it has very different global incentives. "Hey, all I need to do is contract typhus and then I can collect money for not working!"
This is a good discussion, but let's not get silly.
Typhoid Mary was a very unusual case in that she was a carrier but didn't have any symptoms. I really don't think there would have been a problem with people intentionally contracting typhus in order to get benefits and forgetting about the dying part.
A post from Gregory Cochran's and Henry Harpending's excellent blog West Hunter.
The commenter Ron Pavellas adds:
The Wasserman Test.