Syphilis is caused by infection with the bacteria Treponema pallidum. Infection with the bacteria progresses in stages, with the final and most dangerous stage sometimes occurring 10-20 years after the initial infection. Although syphilis can cause serious medical problems and may even be fatal if it is allowed to progress to the final stage, it is easily cured with antibiotics if it is diagnosed within the first few years after infection.

Syphilis can also cause serious problems for a pregnant woman and her baby. The bacteria can infect the growing fetus, increasing the risk of stillbirth or death shortly after birth.

Infection with syphilis also increases the risk of transmitting and contracting HIV because syphilis sores bleed easily and also provide a vulnerable area for infection with the HIV virus.


Syphilis is passed by contact with a syphilis sore during vaginal, anal, or oral sex. Sores are typically found on the outside of the genitals or around the anus, although they may also be inside the body, including in the vagina or the rectum, where they cannot be seen. Sores may also occur on the lips or mouth.


The only sure way to avoid contracting syphilis is to abstain from sexual contact or to be in a mutually monogamous relationship with a partner who has been tested and shown to be free of the infection.

If you do engage in sex and are not sure of your partner's STD status, condoms can reduce the risk of transmitting syphilis only if the area affected is covered by the condom. Syphilis sores may occur in areas that are not covered by a condom, and they may not be large or obvious.


Primary syphilis is the first stage of the disease. Symptoms typically occur between 10-90 days after exposure to the infection. In this stage a skin lesion appears at the point where the infection entered the body, usually the genitals, anus, or (less commonly) the mouth. The lesion is called a chancre and is typically firm, round, small, and painless. Typically, there is only one chancre present, although multiple chancres may appear. The lesion or lesions last 3 to 6 weeks and disappear without treatment.

Secondary syphilis occurs approximately one to six months after the primary infection. Typical symptoms include:

• Reddish-pink, non-itchy rash on the trunk and extremities affecting the palms of the hands and soles of the feet
• Fever
• Sore throat
• Tiredness
• Weight loss
• Headache
• Muscle aches

Latent syphilis begins after the symptoms of primary and secondary syphilis go away. In this stage, there are no outward symptoms, although the infection is still present in the body. The latent stage may last for years. In about 15% of people who are never treated for syphilis, the disease will progress to a final stage, the late stage, which can appear 10-20 years after initial infection. In the late stage, the disease can cause serious damage to the internal organs, blindness, paralysis, dementia, and even death.


Syphilis can be diagnosed by a health care provider through lab tests on a sample from the chancre (if one is present) or through a blood test.


Syphilis can be easily cured with antibiotics in its early stages. Infections within one year require only one dose of antibiotics, while infections within a few years require additional doses.

People who have been treated for syphilis are not immune to the disease and can be re-infected if their parters are not also treated, or if they have sex with a new partner who is infected.

For More Information: 

The CDC STD fact sheets are a good source of current, accurate information about syphilis, as well as the American Social Health Association.

This information is provided for educational purposes only and is not intended to substitute for medical advice. If you have any symptoms that you suspect may indicate an STD or other infection, please consult a doctor or medical professional. A good resource for STD treatment and family planning services is
See more: