Anthony S. Fauci, MD, Voice of Reason and Director of the NIH National Institute of Allergy and Infectious Diseases since 1984.
John Snow, a founder of modern epidemiology, figured out that cholera was spread through water. His findings led to major changes in urban water and waste systems and improvments in public health.
Thomas Hodgkin was a British pathologist and pioneer in preventive medicine who in 1832 described the disease that would come to be named Hodgkin's lymphoma — 30 years later when it was described anew by Samuel Wilks.
Martinus Willem Beijerinck was a Dutch microbiologist and botanist who was one of the founders of virology and environmental microbiology. No human ailments bear his name, but a crater on the moon does.
Antoine Marfan was a French pediatrician whose observations of a patient with unusally long fingers and limbs led to the identification of a connective tissue disorder that now bears his name (Marfan syndrome).
Friedrich Loeffler was a German bacteriologist who discovered the organism that causes diphtheria and whose work eventually helped lead to the development of a vaccine for it. He had a fantastic mustache.
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