The Integrity of the Body: A Discussion of Modern Immunological Ideas

Implicit in this observation are the two basic doctrines of infectious disease, that each is due to a specific microorganism and that postinfectious immunity is also specific. It is no accident that experimental work on immunology, and for that matter on virology, dates from Jenner's famous experiment with 'matter' from the finger of the dairymaid, Sarah Phelps.