Skip to content

Syphilis is a generally hazardous communicable disease caused by a spirochaete bacterium called Treponema pallidum. Most of the syphilis infections detected in Finland have been caught in Estonia. In recent years, the number of the infections has increased, particularly as a result of sex between men.

Syphilis is divided into primary, secondary, latent and tertiary stages. At the primary stage, the syphilis test may be negative. During pregnancy, syphilis is transmitted to the foetus via the placenta. Transmission occurs particularly during the third trimester: the foetus is then almost certain to become infected and may die as a result.


At the primary stage, a painless primary sore appears within 3 to 4 weeks after infection but heals within a few weeks. Local lymph nodes also become swollen.

During the secondary stage, within 6 to 8 weeks after infection, general symptoms such as fever, rash and enlarged lymph nodes appear.

If left untreated, the disease progresses to the latent stage within a year after infection. There are no symptoms during the latent stage.

The tertiary stage causes some patients complications several years after they have become infected; these include skin changes, cardiovascular changes and changes involving the central nervous system.


If you suspect an infection, a screening test based on Treponema pallidum antibodies (S-TrpaAb) can be performed in student healthcare. If this test is not available, a cardiolipin test (S-KardAb) and Treponema pallidum (S-TPHA) test will be carried out.

To confirm the syphilis diagnosis, a clinical examination is also required. A sample can be taken at a venereal diseases outpatient clinic, which can look for and detect spirochaetes in lesion fluid by means of dark-field microscopy. The diagnosis can be confirmed immediately.


The primary treatment for syphilis is procaine penicillin. Those with penicillin hypersensitivity can be treated with ceftriaxone.

Information sources: The Finnish Medical Society Duodecim: Terveysportti, Lääkärin tietokanta database

FSHS General Practitioner / 29th March 2022

Service options