The Greatest Benefit to Mankind: A Medical History of Humanity (The Norton History of Science)

by Roy Porter

Many of the worst human diseases were created by proximity to animals. Cattle provided the pathogen pool with tuberculosis and viral poxes like smallpox. Pigs and ducks gave humans their influenzas,

But the body was to be subordinated to the soul, and healing, like every other temporal activity, had to be under ecclesiastical regulation.