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Syphilis is a sexually transmitted infection (STI) caused by the bacteria Treponema pallidum. The infection progresses in stages.

How is syphilis spread?

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Syphilis is passed to a partner during sexual contact (vaginal, oral, or anal).

What are the symptoms?

Symptoms will vary depending on the stage of the infection:

Primary Syphilis (1st Stage) 

  • Symptoms usually develop 3 days to 3 months after contact. 
  • A painless open sore develops around the genitals, rectum and/or mouth.
  • The sore will heal on its own, but the infection remains. 

Secondary Syphilis (2nd Stage) 

  • Symptoms usually develop 2 to 24 weeks after exposure.
  • A rash can develop anywhere on the body, including on the palms of the hands and soles of the feet.
  • Flu-like symptoms develop, including headache, slight fever, fatigue, loss of appetite, weight loss, and sore throat. 

Latent Syphilis (3rd Stage)

  • Latent syphilis occurs after secondary syphilis.
  • Typically, there are no symptoms.

How can I be tested for syphilis?

  • A blood test is done.

How is syphilis treated?

  • A doctor will give you antibiotics.
  • Avoid all sex (oral, anal, and/or vaginal) for 7 days after taking the medication.
  • Do not have sex with your current partner until they are tested and treated.

What about partners?

  • Individuals who test positive for syphilis are asked to tell all sexual partners so they can be tested and/or treated. A public health nurse is able to help contact sexual partners as needed.

Is follow up needed?

  • Yes. After treatment, blood tests are needed to show that the infection has been treated properly.

Things to think about:

  • Longstanding, untreated syphilis can damage the heart, the nervous system and other major organs.
  • Individuals infected with syphilis are at greater risk of getting and spreading other STIs, including HIV.
  • Taking medication will treat syphilis but any damage that has been done to the body before treatment cannot be reversed. 

How can I reduce my chances of getting and spreading syphilis?

  • Avoid sex.
  • Use condoms/dental dams every time you have sex, even if you are using another form of birth control.
  • Do not share sex toys.

Get tested:

  • After any type of unprotected sex
  • After your last partner and before a new partner

To help protect against STIs, get vaccinated for hepatitis A, B, and HPV.


Contact Us

For more information, please contact The Clinic at 519-663-5317.

Date of creation: September 1, 2011
Last modified on: June 17, 2022


1Canadian Federation for Sexual Health Retrieved from
2The Society of Obstetricians and Gynaecologists of Canada Retrieved from