The Vault

19th-Century Maps Tracking Major Diseases Across the United States

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In a group of five maps published in 1874, Dr. Sidney H. Carney, then Associate Medical Director for the New York Life Insurance Company, used data from the company’s files to represent incidences of disease in the eastern United States. The charts show prevalence of malaria, pneumonia, rheumatism, typhoid fever, and phthisis (an archaic term for tuberculosis).

In a blog post on the making of the maps, medical geographer Brian Altonen speculates that Carney may have decided to chart five of the diseases that were then commonly understood as being tied to the physical environment (and, therefore, to geography). The true causes of these afflictions—some of which, like malaria, could indeed be tied to place—wouldn’t be understood for years to come.

In his position with the New York Life Insurance Company, Carney was witness to a huge expansion in the life insurance industry in the post-Civil War period. With the opening of many new firms in the 1870s, competition was fierce.

In a note near the top of the map, directed to “Railroads, Express, Telegraph, and other Companies,” Carney gives some indication as to the maps’ intended audiences. These companies could request the reproduction of “any portions of this sheet as independent and complete Maps, with new titles, borders, etc.”

The maps represented an innovative attempt to set New York Life apart as a company that understood the needs of its corporate customers. Railroads considering expansion might have found it helpful to have information on disease prevalence readily available; in turn, New York Life could hope to strengthen its relationship with those companies.

Click on the images to reach zoomable versions, or visit the maps’ page on the Library of Congress website.


Library of Congress


Library of Congress


Library of Congress

Phthisis (TB).

Library of Congress

Typhoid fever.

Library of Congress