Syphilis is an STI that we mainly see in men who have sex with men. Nine out of ten people in whom we find syphilis are in this group.  At ZIZ we find syphilis in around one in fifty people who test for it. It is a bacterium that you can carry for a long time. Syphilis can be treated effectively with antibiotics, which you receive as an injection into your buttock muscle. We also advise telling your sexual partner(s) that you have tested positive. 

Syphilis is an STI caused by the bacterium Treponema pallidum. 

If you test through ZIZ, the result is also listed under this name in the results portal. 
 

The bacterium is usually passed on through sex. You can get it in your penis, vagina, anus and/or mouth. 

Syphilis can also be passed from mother to child. In the Netherlands, a syphilis test is therefore a standard part of antenatal screening. 

Nine out of ten people in whom we find syphilis are men who have sex with men. Your chance of having syphilis is therefore higher if you are in this group. 
 

At ZIZ we find syphilis in around one in fifty people who test for it.

The chance of syphilis being passed on during sex depends on several factors. If someone has active syphilis, this can be as high as a 30% chance of transmission per sexual contact.  

Without treatment, syphilis can stay in your body for a very long time. It can cause symptoms, but these do not necessarily appear straight away. Symptoms can also develop only after 10–30 years.  

Yes, having had a syphilis infection does not protect you against a new infection.

The symptoms of syphilis can differ depending on the stage of the illness.

In general:

Primary syphilis: a firm, painless swelling at the site of infection (genitals, anus or mouth). After a few days it breaks down in the centre and forms a kind of crater or ulcer.

Secondary syphilis: around 3–6 weeks after the swelling appears, untreated patients often show the signs of secondary syphilis. These consist of small spots over the whole body, including the palms of the hands and soles of the feet. On the scalp it can cause bald patches. However, many other symptoms can also occur, such as fever, feeling generally unwell, muscle pain and problems such as reduced vision or hearing.

Latent syphilis: after these first stages of syphilis comes a period in which there are hardly any symptoms, but the bacterium is still present in the body.
 

Tertiary syphilis: 2–30 years after infection, untreated patients can develop thicker swellings in the skin. You can also develop problems in various parts of the body, such as your heart, liver, brain or eyes. We rarely see this in the Netherlands.

It should be added that syphilis can also cause a wide variety of other non-specific symptoms. In medicine, syphilis is therefore sometimes called 'the great imitator'. 

You test for syphilis with a blood test. If you have never had syphilis before, we look for antibodies. If you have had syphilis in the past, we do a different blood test that looks at disease activity (RPR test). 

After four weeks, the test detects 80% of all syphilis infections. 
After six weeks, the test detects more than 95% of all syphilis infections.
After twelve weeks (3 months), the test detects 100% of all syphilis infections.  

To rule out syphilis with 100% certainty, we therefore advise testing after three months (or repeating the test at that point, depending on the risk). 

If you have symptoms that fit primary syphilis (a hard, painless swelling or ulcer on your genitals), you can also choose to use the photo consultation. Our dermatologist will then assess whether your symptoms could fit syphilis. 
 

We treat syphilis with two penicillin injections into your buttock muscles. This is usually a one-off treatment. If the infection may have been present for more than a year, you need to be treated three times, with a week between each treatment. Treatment for syphilis is also always free at ZIZ.

In general, the following advice applies:

- With primary syphilis, it is worth telling partners from the past 3 months. 

- With secondary syphilis, it is worth telling partners from the past 6 months.

- With syphilis of unknown duration, it is worth telling partners from the past 12 months.
 

Yes, after treatment you need to be tested again to check that disease activity has fallen. This is usually after three or six months. During your treatment we will discuss what applies to you.