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Biography of Jesse Lazear

Jesse W. Lazear was born in Baltimore County, Maryland, and graduated from the Johns Hopkins University with an A.B. in 1889. He received his M.D. from Columbia University in 1892. After study in Europe, he returned to the Johns Hopkins Hospital as the assistant resident physician from 1895 to 1896. Lazear served as a member of the Johns Hopkins medical faculty as assistant in clinical microscopy from 1897 to 1900, and made valuable contributions as a teacher and investigator. In February 1900, he became an acting assistant surgeon in the United States Army assigned to Havana, Cuba, to investigate the causes of malarial and yellow fevers. To test the theory that mosquitoes were instrumental in the transmission of yellow fever, Lazear subjected himself to the bite of a mosquito. Two weeks later, he died of the disease on September 25, 1900, in Quemados, Cuba. A group of his Johns Hopkins colleagues, including William Osler, William Thayer, and Stewart Paton, initiated a subscription for a memorial tablet. On October 5, 1904, an inscribed bronze tablet was presented by United States Medical Corps Assistant Surgeon James Carroll, an associate of Lazear on the U.S. Army board in Cuba. The memorial tablet is located in the main corridor of Johns Hopkins Hospital. Jesse W. Lazear was awarded the Congressional Medal of Honor posthumously in 1929.

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Biography of Juan A. del Regato

Juan Angel del Regato (1909-1999), the donor of the Jesse Lazear Collection, held a life-long interest in the research of the U. S. Army Yellow Fever Commission. He was born in Camaguey, Cuba in 1909, nine years after the commission had demonstrated through experimentation with human subjects that the mosquito was the vector of transmission of Yellow Fever. Camaguey was also the birthplace of Carlos Finlay (1833-1915) who had first proposed in 1881 the theory of the mosquito as the vector of the disease. Del Regato’s father promoted Finlay as a role model to his son and encouraged him from an early age to become a physician.

In 1926 when del Regato began his medical studies at the University of Havana, one of his professors was Aristides Agramonte (1868-1931), who had been a member of the U.S. Army Yellow Fever Commission. Agramonte, another native of Camaguey, knew Jesse Lazear well both as a member of the Yellow Fever commission and as a classmate at Columbia University’s College of Physicians where they both received their medical degrees in 1892.

After the University of Havana was closed because of political disturbances, del Regato went on to Paris to complete his medical degree. From 1934 -1937 del Regato had a postgraduate appointment at the Radium Institute where he specialized in the new field of radiation therapy. In 1938 he immigrated to the United States where he had a long and distinguished career in radiation therapy. While publishing regularly in his area of medical specialization, he also contributed significantly to the literature on the histories of radiation therapy and Yellow Fever research. In addition, del Regato became actively involved in various efforts to recognize and memorialize Jesse Lazear’s contributions to Yellow Fever research.

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Scope and Content

The Juan A. del Regato Collection of Jesse W. Lazear Materials contains items compiled by del Regato towards his interest in writing a biography of Jesse Lazear. While a monograph was never realized the collection did provide source material for several articles he authored on the subject of Lazear and the Yellow Fever Commission. The biographical documents he gathered relating to Lazear are primarily photocopied items collected over the course of several years of research. Some documents were provided by members of the Lazear family, some by government agencies, and some by private repositories. Much of the core collection of documents, are from the Philip S. Hench Walter Reed Yellow Fever Collection at the University of Virginia, bearing that library’s stamp. The collection includes copies of Lazear’s academic records and degrees, army records, photographs, some research data on mosquito inoculation (1882-1900), as well as journal articles, tributes, memorials and other dedications to Lazear written after his death (1900-1970).

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Additional Links

U.S. Army Yellow Fever Commission Exhibit at University of Virginia

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