Syphilis guide

What is Syphilis?

Syphilis is sometimes referred to as "the great imitator" because many of its early signs and symptoms mimic those of other diseases. According to the Centers for Disease Control and Prevention (CDC), the number of syphilis cases has been steadily rising since 2000, predominately among women and men who have sex with men (MSM)... in fact, about 62% of reported new syphilis cases are among MSM.*

Syphilis is caused by a bacteria, Treponema pallidum, that can be passed from person to person through direct contact with a syphilis sore during unprotected vaginal, anal and oral sex. Sores can occur on the penis, vagina, anus or rectum, or on the lips and inside the mouth. It's also possible for a mother to pass syphilis to her baby during pregnancy or delivery, potentially causing miscarriage or stillbirth, or seizures and developmental delays in the baby.

The good news is that syphilis, in its early stages, is easily treated and curable with antibiotics...most commonly, penicillin. Left untreated, however, syphilis can lead to serious health problems down the road – including brain, cardiovascular and organ damage – and increase your risk of getting other STDs, like HIV.

Syphilis is most infectious during the primary and secondary stages of infection...and the earlier syphilis is diagnosed, the more successfully it can be treated and cured.


Last reviewed by Lisa Oldson, MD, January 2011.

Lisa Oldson, MD

STD expert

"The first thing I tell a patient about STDs is that if you're worried about one STD, you should probably worry about all STDs. In other words, if you had unprotected sex and you're worried about a possible HIV exposure, it's important to understand that hepatitis can be spread in the same fashion...ditto for chlamydia, gonorrhea, herpes and syphilis."

Get tested today. We offer Fast, private & affordable STD testing.
Need assistance?