<P> The Tuskegee Study of Untreated Syphilis in the Negro Male, also known as the Tuskegee Syphilis Study or Tuskegee Syphilis Experiment (/ tʌsˈkiːɡiː / tus - KEE - ghee) was an infamous clinical study conducted between 1932 and 1972 by the U.S. Public Health Service . The purpose of this study was to observe the natural progression of untreated syphilis in rural African - American men in Alabama under the guise of receiving free health care from the United States government . The study was conducted to understand the disease's natural history throughout time and to also determine proper treatment dosage for specific people and the best time to receive injections of treatments . </P> <P> The Public Health Service started working on this study in 1932 in collaboration with Tuskegee University, a historically black college in Alabama . Investigators enrolled in the study a total of 622 impoverished, African - American sharecroppers from Macon County, Alabama . Of these men, 431 had previously contracted syphilis before the study began, and 169 did not have the disease . The men were given free medical care, meals, and free burial insurance for participating in the study . The men were told that the study was only going to last six months, but it actually lasted 40 years . After funding for treatment was lost, the study was continued without informing the men that they would never be treated . None of the men infected were ever told that they had the disease, and none were treated with penicillin even after the antibiotic was proven to successfully treat syphilis . According to the Centers for Disease Control, the men were told that they were being treated for "bad blood", a colloquialism that described various conditions such as syphilis, anemia, and fatigue . "Bad blood"--specifically the collection of illnesses the term included--was a leading cause of death within the southern African - American community . </P>

When did the tuskegee syphilis study start and end
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