Simultaneous infection with Treponema pallidum and herpes simplex virus

Two cases are presented of simultaneous infection with Treponema pallidum and herpes simplex virus. The occasional concurrence of these diseases suggests that all cases of herpes genitalis, including those with negative darkfield examinations and initial nonreactive serologic tests for syphilis, should be followed in two to four weeks by a repeat serologic test for syphilis.