Syphilis is a chronic sexually transmitted disease caused by the bacterium Treponema pallidum. In Switzerland, the number of new cases of syphilis has risen sharply in recent years. A large proportion of those infected are men, the majority of whom have sex with men.

The (mucus) skin lesions in syphilis are highly contagious, especially in stage I. You can become infected during unprotected sexual, oral or anal intercourse. If the lesion is in the mouth during the primary stage, kissing may also be contagious.

What are the signs and consequences of syphilis?

Syphilis disease progresses in different phases:

Primary stage/Stage I of syphilis: primary ulcer

After 10 to 21 days – sometimes up to three months – a painless hard ulcer appears at the skin/mucous membrane site where the infection occurred, sometimes multiple ulcers. Often this is not even noticed. There are a lot of pathogens in the ulcer. The regional lymph nodes are swollen. At the same time, there are already countless pathogens in the blood. The ulcer remains for a few weeks and then disappears by itself.

Secondary stage/stage II of syphilis: skin rash

After about 4 to 10 weeks, the bacteria have spread throughout the body. Lymph nodes swell, and you get a rash – reddish-brownish spots. These can be sparse, but also very numerous and extensive. It is typical for syphilis that the spots can also appear on the palms of the hands and soles of the feet. Flu-like signs of illness are possible. The skin symptoms heal spontaneously after several weeks. During this time, your scalp may also change and localized hair loss may occur. Syphilis is also called the chameleon of medicine, it can often be confused with symptoms of other diseases.

Later syphilis stages:

Syphilis can cause damage to different parts of the body at different stages. After the secondary stage, damage to various parts of the body is possible, after varying lengths of time without symptoms. A particular characteristic is the attack on the nervous system.

How is syphilis treated?

If syphilis is treated during the first or second stage, one to three penicillin injections at weekly intervals are sufficient, depending on the duration of infection. In later stages and/or when the nervous system is affected, prolonged high-dose penicillin treatment is required.