The figures, which are for 2024, show that the number of cases of both gonorrhea (106,331) and syphilis (45,557) is the highest in over a decade. For gonorrhea, this represents an increase of 303 percent since 2015, and for syphilis, more than doubling.
“Untreated infections can cause severe complications, such as chronic pain and infertility, and in the case of syphilis, problems with the heart and nervous system,” says Bruno Ciando, head of unit at ECDC, in a press release.
Chlamydia at its peak
Syphilis is uncommon in Sweden. Between 2016 and 2021, the number of cases increased, but then the trend turned downward. In 2025, four cases per 100,000 inhabitants were reported.
For gonorrhea, which is the second most common sexually transmitted infection in Sweden, the number of cases per 100,000 inhabitants increased by an average of 8 percent per year between 2016 and 2025 - but now the increase has slowed down, according to statistics from the Swedish Public Health Agency.
"The last two years have been stable," Katerina Crawford, epidemiologist at the Swedish Public Health Agency, told TT.
Chlamydia is already the most common sexually transmitted infection in Europe, with 213,443 cases in 2024. It also tops the list in Sweden, but the situation is quite stable, says Crawford.
A decrease has been observed in recent years.
Very unusual
For congenital, or inborn, syphilis, which is transmitted from an infected pregnant woman to the fetus in the womb, the number of cases in Europe has almost doubled between 2023 and 2024. ECDC has previously highlighted unequal access to healthcare as a problem.
Congenital syphilis is very rare in Sweden. Pregnant women are offered free testing for the disease as early as possible.
"Some years we have no reported cases at all. Other years we see isolated cases, that is, one or two," Crawford told TT.
Facts: Some common sexually transmitted diseases
Chlamydia
The most common sexually transmitted infection in Sweden. The bacterium is easily transmitted during various types of sex. Burning when urinating, pain in the lower abdomen or scrotum are examples of symptoms, but it is common to have no symptoms at all. Treatment is with antibiotics. Testing and treatment are free. In 2025, 25,081 cases were reported in Sweden.
Gonorrhea
A sexually transmitted bacterium. Burning when urinating or pain in the scrotum are examples of common symptoms, but it is common to have no symptoms at all. Treatment is with antibiotics. Testing and treatment are free. In 2025, 4,268 cases were reported in Sweden.
Syphilis
It is a bacterial disease that is uncommon in Sweden. You don't always have symptoms, but a couple of examples are sores on the genitals that don't hurt and swollen groins. Syphilis is a serious disease and can lead to permanent damage to the nervous system and the body's organs after several years if it is not detected and treated. Treatment is with antibiotics. Testing and treatment are free. In 2025, 432 cases were reported in Sweden.
Sources: Public Health Agency of Sweden, RFSU
