What is an antonym for prophylaxis?

The Word prophylaxis means treatment given or action taken to prevent disease.

The antonym would be a Word that means treatment given or action taken to cause disease - in other Words, deliberately infecting the victim with a disease.

Vaccination is a way of deliberately infecting someone with a disease so that their immune system then gears up to prevent later infection by a stronger form of the same disease, or of a related disease. So I guess in a sense, vaccination is an antonym for prophylaxis.

Another antonym would be terrorism (deliberately sending anthrax through the mail) or biological warfare.