At the beginning of the 20th century, despite 20 years of intensive bacteriologic research, the cause of
syphilis was unknown; no diagnostic test and no treatment had been found.
Syphilis was one of the leading causes of morbidity and mortality, and those who had the disease were burdened with a social stigma. It was considered a disease of "bad blood." But success was soon to follow. In only 10 years, from 1900 to 1910, the Treponema pallidum was discovered as the cause of
syphilis. Animal models were developed for research. The Wassermann test was "invented" for serologic diagnosis, and Paul Ehrlich proved that
salvarsan, or 606, was effective for the treatment of
syphilis. This success was preceded by 300 failures with related arsenical compounds. The scientific, medical, social, ethical, and economic issues of that day have recurred again with the
AIDS epidemic. This earlier drama, therefore, is reflected in the current decade, but the success of Ehrlich, Wassermann, and others in the fight against
syphilis is an optimistic omen that researchers will be equally successful in the fight against
acquired immune deficiency syndrome (
AIDS).