The US Presidential Commission for the Study of Bioethical Issues had said some 5,500 Guatemalans were involved in all the research that took place between 1946 and 1948, with a view to applying the results on US troops stationed around the world.
Of these, some 1,300 prisoners, psychiatric patients and sex workers were deliberately infected with syphilis, gonorrhoea or another sexually transmitted disease, chancroid.
Concentrations of bacteria were injected into the eyes, the central nervous system and male genitals. Mr Mejia says this was behaviour very similar to that of the scientists in Nazi Germany.
www.bbc.co.uk/news/world-latin-america-14751441