This paper describes the significant changes in the relationship between Aedes aegypti mosquitoes and the human population in the Americas from the 1800s to present. First, the history of the arrival of the mosquito, the consequent epidemics of yellow fever and dengue, and the eventual implication of the mosquito as vector is described. Second, the Pan American Health Organization's Aedes aegypti Eradication Program is discussed and the potential threat to the Americas of development of the dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) is emphasized. Third, the limited efforts of the United States to control its A. aegypti population, which has serious implications for the success of the control of the species in the rest of the Americas, are commented upon. It is shown, in conclusion, that politics and economics, in addition to the state of biomedical knowledge, have a significant impact on the relationship between the mosquito and human populations in the Western hemisphere.