Know syphilis in all its manifestations and relations. —Sir William Osler (1897)
The above quotation, one of the most frequently cited in medicine, refers to lessons that the pathobiology of Treponema pallidum infection provides in helping us to understand other areas of medicine. The tremendous range of clinical manifestations of syphilis are reemphasized by Rosen et al1 in this issue of the Archives. The quotation could also refer to the complex relationships between syphilis and human society and to the lessons that these relationships can provide about understanding how other diseases occur. In the last several years, syphilis has shown that it has additional lessons for us.
During the decade from 1970 to 1979, despite relatively stable overall incidence rates, important changes occurred in the epidemiology of syphilis. Syphilis became more concentrated in large cities, and a progressively larger proportion of syphilis occurred in homosexual and bisexual men