"Here I have been sitting reading that most wonderful book -- La Roche on Yellow fever -- written in 1853. Forty-seven years later it has been permitted to me & my assistants to lift the impenetrable veil that has surrounded the causation of this most dreadful pest of humanity and to put it on a rational & scientific basis."

Walter Reed wrote these words to his wife at midnight, December 31st, 1900. In Cuba, at the dawn of the twentieth century, the United States Army Yellow Fever Commission had demonstrated irrefutably that the mosquito was the vector of transmission for yellow fever. Cuban scientist Carlos J. Finlay had first proposed such a connection in 1881, but had not been able to prove his theory conclusively to the world scientific community.

Reed and the other members of the Commission, James Carroll, Aristides Agramonte, and particularly Johns Hopkins scientist Jessie Lazear, had sought Finlay's assistance to clarify and ultimately test the mosquito theory. Indeed in the very early stages of the investigation, Lazear lost his life to a case of yellow fever, very likely experimental in origin.

Deeply dismayed at the loss of his friend and colleague, but intrigued by the very real possibility of a solution within reach, Reed designed an experimental protocol which would withstand strict scientific scrutiny. He obtained permission from the military leadership to establish an experimental facility -- which he named Camp Lazear -- near Columbia Barracks, Quemados, Cuba, on the outskirts of Havana. The Commission also sought volunteers from among the U.S. Army corps stationed at Camp Columbia and from recent Spanish immigrants to Cuba. In conjunction with the use of human subjects, the Commission developed perhaps the first formal informed consent forms surviving from a medical experiment.

As Reed noted to his wife, the experiments proved dramatically successful. Mosquito eradication campaigns began immediately in Cuba with remarkably rapid results. Sanitation efforts took hold in South and Central America, Africa, and the American South, largely under the guidance of Rockefeller Foundation scientist Henry Rose Carter. Yellow fever, once so devastating, had been conquered.

In 1937, Mayo Clinic physician Philip S. Hench began a life-long project to document the story of the yellow fever discovery. His monumental collection of manuscripts, printed materials, photographs, artifacts, and research is the source of this digital archive. For more information on the Yellow Fever story, please see our Web exhibit.