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What is syphilis?

Syphilis is a Sexually Transmitted Infection (STI) caused by bacteria.

How can a person get Syphilis?

Syphilis is spread from person to person through direct skin to skin contact with a syphilis sore.  Syphilis sores may be present on the vagina, penis, anus, mouth, lips or in the rectum. Syphilis can spread during vaginal, anal, or oral sex. Syphilis can be passed even if the syphilis sore is not seen or felt, so people can pass syphilis even if they don't know they are infected. Syphilis can also be passed from a pregnant mother to the fetus.

You have a higher risk of infection if you:

  • Have sex without using a latex or polyurethane condom
  • Have multiple sex partners
  • Have another STI or HIV
  • Have sex while high on drugs or under the influence of alcohol (less likely that condoms will be used correctly) 

Who can get syphilis?

Anyone who is sexually active can get syphilis. Having unprotected sex (sex without a condom) increases the chance of getting syphilis. While men and women are at risk for the infection, more than half of the reported cases in the U.S. are in men who have sex with men (MSM).

What are the symptoms of syphilis?

Symptoms of syphilis are different depending on the stage of the disease. The disease has four stages: primary, secondary, latent and tertiary.

Primary Stage Symptoms

  • One or more painless sores (chancre) on the genitals or in the mouth, anus or rectum.
  • The sore lasts 3 to 6 weeks and it goes away on its own. However, if you do not get treatment, the disease moves to the next stage.

Secondary Stage Symptoms

  • Rash on your hands and feet or on other parts of your body. Rashes are often red or brown and usually do not itch.
  • Other symptoms also include fever, sore throat, muscle aches, headaches, hair loss and feeling tired. Symptoms may go away own their own. However, if you do not get treatment, the disease moves to the next stage.

Latent Stage Symptoms

  • No symptom but the disease is detectable by a blood test. This stage can last for many years.

Tertiary Stage Symptoms

  • Symptoms can include difficulty moving your arms, and legs, paralysis, numbness, blindness and heart disease.

How long can an infected person spread syphilis?

People who are not treated are most likely to pass on the infection within the first year of infection. The longer an infected person is left untreated, the higher the risk of serious long term problems.  

How can I find out if I have syphilis?

The only way to know for sure if you have syphilis is to get tested. A healthcare provider usually tests for syphilis from a blood sample. Because untreated syphilis can cause problems for a fetus, all pregnant women should be tested for syphilis. People whose sexual activities place them at risk for syphilis should be tested regularly so they can be treated quickly if infected.

Where can I get tested?

Most health care providers offer testing for syphilis and other STIs. To find a health care center near you, call the Mayor's Health Line at 617-534-5050 or visit

Can syphilis be treated?

Yes, syphilis is usually treated with antibiotic shots. Even after you've been successfully treated, you can be re-infected if you are exposed again. It is important to always use condoms every time you have sex to reduce your risk of getting syphilis and other STIs.

Should my partner get treated?

Yes. If you have sexual contact with a partner who was not treated you can get re-infected.

What happens if syphilis is not treated?

If left untreated, syphilis can cause serious health problems. Long term infection without treatment can damage internal organs. In addition, persons with syphilis are more likely to acquire HIV if exposed. 

Can syphilis affect a pregnant woman and her fetus?

Yes. Syphilis can cause serious problems for a pregnant woman and her fetus. 

How can you protect yourself from getting syphilis?

The only 100% effective way to prevent syphilis is to not have sex. If you do have sex, you can limit your risk by taking the following steps:

  • Always use a latex or polyurethane condom or barrier (dental dam) when having anal, vaginal and/or oral sex
    • Condoms made from "natural" materials may protect against pregnancy but NOT STIs
  • Reduce your number of partners if you choose to have sex
  • Talk with  your partner about their STI status and getting tested
  • Talk with your health care provider about safer sex practices and getting tested
  • Understand that  having sex while under the influence of drugs and/or alcohol can increase the likelihood of unprotected sex
Boston Public Health Commission
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