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In 1855, a modest Cuban physician named Carlos Juan Finlay graduated from Jefferson Medical College. He was among JMC’s first dozen Hispanic graduates, initially signing the registrar’s log as “Charles”. He left Philadelphia at the age of 22 to begin private practice. Preceptor and close friend S. Weir Mitchell, among others, urged Finlay to work among the burgeoning Spanishspeaking population in New York City, but he returned to Cuba and set up practice in Matanzas, a town near Havana. He took a binocular microscope with him, similar to one used byMitchell, which would serve him well for many years.

During his years of medical practice, Finlay developed a keen interest in urban communicable disease. He rejected the common assumption that “miasma”, or fumes producing contagious disease, were the source of infection, and conducted meticulous studies to confirm his theories. While he is best known for his research showing that mosquitoes transmit yellow fever, he also correctly deduced that cholera was water-borne, and that the cotton used to tie the umbilical cord on newborns carried infantile tetanus. His views on cholera and yellow fever earned him the title of “crank” and he was largely ignored. During the 1867-68 cholera epidemic in Havana, he tried to publish his findings in the local paper and was rebuffed by censors. He quietly boiled the water in his home to prevent cholera in his family.

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History of Science, Technology, and Medicine | Medicine and Health Sciences

Latin Heritage Month.  Carlos Juan Finlay: Outrageous, Courageous and Correct