The United States government has apologised for infecting hundreds of people in Guatemala with gonorrhoea and syphilis as part of medical tests almost 60 years ago.
Many of the infected were mentally ill patients and prisoners who did not give their consent.
Secretary of State Hillary Clinton has condemned the research as unethical and reprehensible.
At the time, the US wanted to test vaccines against venereal diseases.
Many of the infected patients were never given adequate treatment.
Evidence of the programme was unearthed by Prof Surab Reverby at the Wellesley College. She says the Guatemalan government gave permission for the tests.
Experiments
No offer of compensation has been made yet but an investigation will be launched into the specifics of the study which took place over four years in the 1940s.
The study by Prof Reverby shows that US government medical researchers infected almost 700 people in Guatemala with two sexually transmitted diseases.
The patients, prisoners and mental heath patients, were unaware they were being experimented upon.
The doctors used prostitutes with syphilis to infect them, as they tried to determine whether penicillin could prevent syphillis, not just cure it.
The patients were then treated for the disease but it’s unclear whether everyone was cured.
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