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Fracastoro
Disease spreads by little "seeds"
Anton van Leeuwenhoek
Father of microscope (200x magnification); viewed and drew the 3 basic shapes of bacteria
Jan Baptista von Helmont
Recipe for mice (spontaneous generation)
Louis Pasteur
Final evidence of biogenesis using swan-necked flasks; also known for technique of pasteurization
Edward Jenner
Cowpox and small pox correlation; small pox vaccine/immunity
Semmelweis
Hand washing with chlorine water
Snow
Founder of epidemiology
Robert Koch
Koch's postulates
Joseph Lister
Aseptic (sterile) procedure
Gram
Gram staining technique
Fleming
Penicillin
Salk
IPV
Sabin
OPV
Francesco Redi
disproved spontaneous generation (meat/maggots)