This episode imagines Louis Pasteur returning to confront modern measles outbreaks and vaccine hesitancy. It traces his work dismantling miasma theory, proving microbes cause disease, and transforming vaccination into scientific practice.

Pasteur’s likely reaction is anger and moral clarity: measles resurgence is avoidable, the result of choice, misinformation, and a failure of civic responsibility. The episode argues that scientific knowledge brings ethical duties and that refusing vaccines endangers children and society.