(Treponema pallidum)

About Syphilis

​Syphilis is caused by a bacterium called Treponema pallidum, it is usually spread by sexual contact. Syphilis develops in stages and symptoms vary with each stage.

Transmission Symptoms When to test How often to test Why you should test

How is syphilis transmitted?

Syphilis is caused by a bacterium called Treponema pallidum that gets into your body through tiny breaks. These breaks can be on the skin or on the delicate surfaces (mucous membranes) just inside the body, and sometimes they can be caused by the friction of sex. The bacterium that causes syphilis doesn’t survive well outside the body, and because of this, it needs close contact between people to go from one person to another. But where you’re having close contact with another person, the syphilis bacterium is really good at getting into your body. In fact, anything from kissing and fingering to oral, anal, and vaginal sex can let the syphilis bacterium in. And once the bacterium gets in, it has tricky ways of hiding from the immune system, allowing it to live in your body for a long time.

​What are the symptoms of syphilis?

​Syphilis will show up differently in your body the longer you live with it, and you’ll generally experience it in three stages. But not everyone goes through all three stages and sometimes symptoms can be mild and missed. Additionally, symptoms can resolve without medicine, but this doesn’t mean it’s gone – you still have the syphilis bacterium in your body. The average time it takes to show symptoms is 3 weeks. The stages are as follows:

  • The first stage of syphilis usually involves a painless sore or ulcer, generally on the genitals, although it can appear in other places like inside the mouth. You’ll usually notice this sore or ulcer within 2 to 10 weeks after the syphilis bacterium gets into your body. Even if these sores or ulcers go away without medicine, you still need medicine to get rid of the syphilis bacterium – which will stop it progressing to the later stages.
  • The second stage of syphilis usually occurs a few months after the first stage. This second stage can involve fatigue, fever, and sore muscles, and it is often characterised by a rash. This rash can show up all over the body, including the soles of the feet and palms of the hand. And just like the first stage, this second stage can go away on its own. But if it does, you still need medicine to stop syphilis from progressing to the third stage.
  • The third stage of syphilis can occur 3 to 30 years later, after a period of the syphilis bacterium hiding in your body without symptoms. Over this time, the bacterium will get deeper into your body, into the brain, nerves, and blood vessels, and make you very unwell. But this stage is avoidable by testing regularly and taking medicine in the earlier stages if you have syphilis.

How soon after sex should I test for syphilis?

​The window period for syphilis is 3 months. This is the time between coming into contact with syphilis and when a test is able to detect it. 

If a sexual partner has let you know that you may have come into contact with syphilis, or if you have symptoms that sound similar to syphilis, don’t freak out. But it is a good idea to see a doctor, as they might decide to give you medicine straight away. If you live in Brisbane, our RAPID clinic can test for syphilis.  A great list of doctors to go to can be found here, or you can visit your local sexual health clinic.

​How often should I test for syphilis?

​Usually, testing every 3 to 12 months is appropriate, depending on how much sex you’re having.

A good general rule is to test closer to every 3 months the more active you are.

Why is it so important to test for syphilis?

Taking medicine will get rid of the syphilis bacterium. However, where you don’t take medicine and the bacterium is hiding in your body, syphilis can lead to complications – especially if you’re pregnant. It can lead to stillbirths or cause significant harm to unborn babies.

So, it is important to get tested and treated.

Hepatitis C

Hepatitis C is a bloodborne virus that causes inflammation of the liver. This virus is present in the blood of a person living with hepatitis C and can be spread through blood-to-blood contact. The current treatment can cure hepatitis C in more than 90% of people.


Gonorrhoea is a common bacterial STI, and doesn’t always have symptoms. It can affect anyone, regardless of gender, who has any kind of unprotected sex (without condoms) with someone who has the infection. It can be treated with antibiotics.


Chlamydia is a very common bacterial STI, and often people do not realise they have it. It can affect women and men of all ages, but most frequently occurs in young people who regularly change sexual partners. It can usually be easily treated.

HPV & Related Cancers

HPV is the most common sexually transmitted infection, but research indicates that types 16 and 18 cause 70% of cervical cancers and over 80% of anal cancers worldwide.

Our trained team is here to help you should you have any questions or need support. You can contact QPP toll free from a Queensland land-line on 1800 636 241 or (07) 3013 5555 nationally, email us at or use our contact us form.

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