HISTORY OF THE CONTROL OF YELLOW FEVER 491 



per year. After the yellow fever investigation, Major Gorgas 

 was sent by the United States government to rid Havana of mos- 

 quitoes. Within ninety 

 days there was not a single 

 new case of yellow fever. 



The Isthmus of Panama 

 was considered a plague 

 spot for yellow fever and 

 malaria. About 1880, the 

 French started building a 

 canal across the Isthmus, 

 but had to give it up, be- 

 cause of the prevalence of 

 the diseases which caused 

 the death of thousands 

 of the workers. Twenty 

 years later, the United 

 States bought the Isthmus 

 from the French. Since 

 Gorgas had helped to rid 

 Havana of yellow fever, 

 the government sent him 

 to eradicate yellow fever 

 from Panama. There were 



neither suitable drains nor water supply in the cities, so Gorgas 

 had a system of drainage constructed, the streets paved to elimi- 

 nate water-filled ruts, the water supply of the cities improved, and 

 the windows and doors screened against mosquitoes. Pools were 

 either drained or oiled. Endless care, thought, and time were 

 devoted to this work. In about two years yellow fever was 

 eradicated from the Isthmus and the building of the canal was 

 made possible. This was as great a hygienic feat as the canal 

 was an engineering feat. 



Courtesy Rockefeller Institute 



The structure isolated by Dr. Noguchi which is 

 believed to be the cause of yellow fever. In the photo, 

 the spirochaete is magnified 3000 times. 



