Did Ronald Coase die in vain?
The problem is that in the generality you want to apply it the Coase theorem is false.
But we do have working tort law in this area. It is a tort to imprison someone, and it is a tort to deliberately or negligently infect someone with HIV. So the Coase theorem does apply.
A post from Gregory Cochran's and Henry Harpending's excellent blog West Hunter.
The commenter Ron Pavellas adds:
The Wasserman Test.