Syphilis fact sheet

What is syphilis?

Syphilis is a sexually transmitted infection caused by a bacteria called Treponema pallidum.

How is it transmitted?

You can catch syphilis through oral, vaginal or anal sex with a person who has syphilis. It is transmitted through skin-to-skin contact with an infected area.

The chance of catching syphilis is greatly reduced by using condoms during sex. Condoms also protect you against other sexually transmissible infections.

Syphilis is highly contagious when a sore or rash is present. More rarely, syphilis is transmitted from mother to baby during pregnancy.

What are the symptoms?

Not all people with syphilis have symptoms so you may not know you have it unless you have a blood test for it. There are three stages of infection known as primary, secondary and latent syphilis.

The symptoms vary according to the stage. People with primary or secondary syphilis are infectious to their sexual partners.

Primary syphilis

A hard, painless sore occurs usually on the genitals or at other sites of sexual contact such as the mouth or anus. Because it is typically painless and may occur in hidden sites (eg cervix or mouth) you may not notice it. The sore or ulcer usually appears three to four weeks after infection.

However, it can occur 10 to 90 days after infection which may make it difficult to know when you caught syphilis. The sore usually heals by itself within about four weeks.

Even though the sore heals, if you have not had treatment, you still have syphilis and can pass it on to others.

Secondary syphilis

Symptoms may occur two to four months after infection and last several weeks. There may be a flat red skin rash on the back, chest, hands and feet. Other symptoms include fever, swelling of the glands in the groin and armpits, a genital rash, hair loss and tiredness.

If untreated, these symptoms may come and go for up to two years. While the rash is present, secondary syphilis is highly infectious.

Latent syphilis

If syphilis is not treated in the primary or secondary phase it becomes latent. At this stage there are no symptoms and it is only picked up on blood tests. If syphilis is diagnosed and treated early in the latent phase there are usually no problems.

About a third of people who have latent syphilis but are not treated over time develop tertiary syphilis. This can show as serious problems with several organs, mainly the brain and heart.

If you have latent syphilis you may need further tests, specialist review and longer treatment. Latent syphilis is not infectious and can be avoided by early treatment.

How do you test for syphilis?

Blood tests and a swab may be taken from the sore. Blood tests are also used to monitor your body’s response to the treatment.

How is it treated?

Penicillin is the usual treatment of syphilis. If you are allergic to penicillin there are alternative treatments. It is important to have repeat blood tests to check that the treatment has worked.

When is it safe to have sex again?

You should not have sex until your rash or sore clears up and at least seven days after treatment.

Do I let my partners know?

Yes, it is very important all (both regular and casual) sex partners are checked because if syphilis is not treated it can cause serious problems later on. All of your sexual partners from the last few months should be checked by a doctor.

How can I let my partners know?

Most people find this is best done directly, either in person or by phone call or text message. If you don’t feel comfortable contacting partners personally, there are two websites to help you send a free and anonymous text message or email:

• Let Them Know is for anyone to use.
• Drama Down Under is specifically for men with male sexual partners.

How do I avoid re-infection?

• It is possible to catch syphilis again even after you have been treated.
• Your best way to avoid catching it again is to tell your partners and make sure current partners are treated.
• Always use condoms with all future partners.
• Have regular sexual health screens.

For free and confidential information and treatment for sexually transmissible infections and information on safer sex call the Sexual Health Service for free anywhere in Tasmania on 1800 765 859.

Sexual health fact sheets translated into other languages can be found at the Melbourne Sexual Health Centre

View all infectious diseases guides and fact sheets