Physician to the World by John M. Gibson is a study of the career of William Crawford Gorgas, focusing primarily on the 22 years from the Spanish-American War until his death at the age of 65. The book details the medical community's gradual acceptance of the mosquito theory as the cause for yellow fever epidemics and follows Gorgas as his initial skepticism gave way to belief while he participated in Walter Reed's massive cleanup of Havana. From this success Gorgas moved to the Panama Canal Zone and a bureaucratic quagmire as he attempted to apply sanitary principles there to control yellow fever and malaria. As canal construction proceeded, assorted red-tape and critics repeatedly thwarted Gorgas's efforts. His particular nemesis was the imperious engineer George Goethals, who ruled the construction project with an iron hand. Gorgas's dogged persistence to make Panama healthy for both Americans and natives eventually succeeded, enabling the project to be completed with minimum loss of life. During World War I Gorgas became U.S. Surgeon General, and finally his reputation equaled his accomplishments. He traveled widely in Europe, South Africa, and South America on behalf of public health improvements and was about to begin another such journey when he died of complications from a stroke in London in 1920.