Treponema pallidum (T. pallidum) remains an important sexually transmitted infection (STI) and is a major public health concern worldwide. Because this bacterium is exceptionally difficult to culture, serologic testing is often used to aid in the diagnosis of this STI.

Advancements in modern molecular assays are also now at our disposal to enable clinicians to request for nucleic acid technologies (PCRs) to directly detect the organism in clinical lesions such as genital ulcers and cervical secretions.