Dr. Jesse W. Lazear, Yellow Fever Chart (1900)

The Spanish-American War was fought in 1898 over Spanish Imperialism in Cuba and the Caribbean. The war ended with the Treaty of Paris, which guaranteed Cuba’s independence; forced Spain to cede both Puerto Rico and Guam to the United States; as well as sell the Philippines to the United States for $20 million. During the war, disease rather than combat was the leading cause of death; primarily typhoid and yellow fever. As a result, the United States formed research organizations to study infectious diseases, including the Yellow Fever Commission. Jesse W. Lazear, a physician and member of the Commission, intentionally contracted yellow fever to test a theory by Carlos Finlay that mosquitos spread the disease. This graph charts Lazear's body temperature from when he contracted the disease on September 19th, until he died on September 25, 1900. The chart helps to exemplify the impact of the industrial period on the spread and study of infectious diseases, as well as urban and rural health and sanitation.