Establishing a locally trained and geographically varied workforce has allowed CDC to have ready and deployable human resources for emergencies or emerging needs anywhere in the world. PHAs are part of a deployable team that can be credited with the eradication of smallpox, the identification of new strains of disease, and the halting of epidemics. PHAs have been called to respond to outbreaks of disease such as hantavirus, Lassa fever, monkeypox, encephalitis, tuberculosis, measles, AIDS, smallpox, polio, Legionnella, Guillain–Barré syndrome, SARS, syphilis, PPNG, babesiosis, and cholera. PHAs were assigned to work in health campaigns such as Guinea worm, malaria, syphilis, diarrheal diseases, yellow fever, yaws, swine flu, and measles. PHAs have been sent to respond to major events such as floods, hurricanes, volcanic eruptions, earthquakes, and the anthrax scare in the U.S. They even were assigned to be poll watchers in select Southern states during the 1972 and 1976 presidential elections.