On the Origin of Syphilis and Contemporary Views of Disease Dynamics

Introduction:

Despite syphilis being a disease of antiquity, diagnosis and treatment remains problematic globally due to a complex biologic pathogen/host relationship and the spread of the disease embedded in human behavior. First documented as an independent disease in 1495, the origin of syphilis has been ambiguous for over 500 years. In the past century, there have been several approaches to investigate the origins of syphilis, but without definitive outcome. A viable syphilis control option became available in the 20th century with the discovery of penicillin, leading to cost effective and safer treatment compared to prior use of mercury- and arsenic-containing compounds. However, despite the availability of antibiotics that can successfully treat syphilis, the disease waxes and wanes at various times and among certain social groups or settings, due in part to risky sexual behavior, a complex clinical presentation (multiple clinical stages including a latent stage where there are no clinical signs), diagnostic challenges and spontaneous healing or unnoticed lesions resulting in failure to seek clinical care or sexual partners not being referred for treatment. Disease ecology of syphilis is highly dependent on human behavior and epidemiology remains the hallmark for surveillance of disease severity, transmission and intervention programs. Here we address contemporary aspects of the origin, control and treatment measures, and modern views of disease ecology of syphilis.

Historically, controversy surrounds the origin of syphilis (Treponema pallidum subsp. pallidum ) which is based on two theories, the Columbian and the pre-Columbian. The Columbian theory suggests that explorers in the late 1400s carried the disease back to Europe from the “New World” and triggered the first documented outbreak of syphilis in Naples during the invasion by King Charles VIII’s army in 1495. This view dominated thoughts on the subject until the 20th century when scientists began to recognize the similarities in clinical presentation between syphilis and other diseases such as leprosy, and proposed that syphilis existed in pre-Columbian Europe but was not recognized as a separate disease until 1495 (pre- Columbian hypothesis).