fbpxSyphilis - Sexperterna



Syphilis is an infection caused by a bacterium calledTreponema pallidum.

Syphilis used to be a very common STI, but it became increasingly rare during the 20th century. The infection has, however, increased quite a bit in recent years among men who have sex with men.


Syphilis does not have any symptoms to begin with, so you could have the infection without realising. Visible symptoms arise in the form of small painless sores on or near the genitals, anus, or mouth and/or a rash, fever, nausea, and tiredness. The sores heal in four to eight weeks. The sores could, however, be so small that they can’t be seen. When the sores heal, the bacteria remain in the body, which means there is a risk of passing the infection on to others. You may also experience a skin rash at a later stage.

Seven to 10 weeks after the first sores you may get new symptoms; fever and swollen lymphatic glands are common symptoms. However, there are not always symptoms, or they are so mild that they go unnoticed. These first two phases are called early-stage syphilis, and during this time there is a high risk of passing the infection on to others during sexual contact.

If syphilis goes untreated it gradually enters a phase called late-stage syphilis, and this is when the infection can cause damage to the heart and brain, or practically any internal organ. Treatment prevents further damage, but any damage that’s already been done is permanent.

How is syphilis passed on?

Syphilis is transmitted through skin contact and through anal, vaginal, and oral sex. The infection can also be passed from mother to foetus during pregnancy. Syphilis can also be transmitted via blood. Since the infection is easily transmitted and it is hard to know if you have it, it’s important to get tested regularly and to protect yourself during sexual contact by using a condom. It can take anything from three weeks to three months before syphilis is detectable in a test. A syphilis test is a blood test and is always free of charge.

If you turn out to have syphilis, you will have to take part in contact tracing. In order to find others who may have syphilis, you’ll be asked who you’ve had sex with recently. It may feel a bit strange, but it’s a way of showing consideration for the people you’ve had sex with. It gives them an opportunity to check that they’re healthy.


Syphilis can be cured with antibiotics as it’s caused by a bacterium. The infection heals if treatment is followed.

Was this article useful?


Chlamydia is the most common sexually transmitted infection in Sweden, and it’s caused by the bacterium Chlamydia trachomatis. The infection can spread quite easily through unprotected sex. Mostly, chlamydia occurs among young (15-29 years)...

Read more


Condyloma, also known as genital warts, is an infection caused by the human papilloma virus (HPV). Generally, the incubation period for condyloma is 2-3 months from transmission, but it can be much longer....

Read more


Gonorrhea is an infection caused by bacteria, and it can be found in the penis, vagina, anus and throat. Not everyone who has gonorrhoea has visible or perceptible symptoms, but if there are...

Read more


Hepatitis is caused by a virus that attacks the liver and causes inflammation. There are various viruses that cause different types of hepatitis (Hepatitis A, B, C, D, E and G). The most...

Read more


There are two different kinds of herpes: Oral herpes and genital herpes. Herpes is a viral infection and both variants are very common in Sweden. It’s estimated that between 70 and 80 %...

Read more


HIV is an infection that can be, among other ways, transmitted during sex. It is classified as a chronic infection because there is currently no cure. There are medications that inhibit the replication...

Read more

HIV and sexually transmitted infections

By sexually transmitted infections (STIs) we mean infections that are passed on through various forms of sex. They are also sometimes called venereal diseases (VDs) or sexually transmitted diseases (STDs). There are many...

Read more


Sexperterna.org is a website aimed at the gay and trans community in Stockholm. Our goal is to offer a positive website about sex, safer sex and enjoyment which encourages and gives information about...

Read more