Malta has the second-highest rate of syphilis in Europe, health experts said on Friday.
Reported cases of the sexually transmitted disease more than doubled in seven years, a report from the European Centre for Disease Prevention and Control (ECDC) showed.
Iceland was the only other country with a higher rate.
The rise has been attributed to unprotected sex, an increase in the number of sexual partners, and the impact of a pill taken before sex to reduce the risk of HIV infection.
There were 62 cases reported in Malta in 2017, which is 13.5 cases per 100,000 people.
That rose from 40 confirmed cases in 2016.
The highest rate was observed in Iceland (15.4 cases per 100,000 population), followed by Malta (13.5), the United Kingdom (11.8) and Spain (10.3). Low rates (below three cases per 100,000 population) were observed in Croatia, Cyprus, Estonia, Italy, Portugal and Slovenia.
Reported cases of the sexually transmitted disease were up by 70% since 2010, with the rise driven by more unprotected sex and riskier sexual behaviour among gay men.
Malta also had among the highest rate of men with syphilis, according to the report. The highest rates were observed in Germany, Iceland, Ireland and Malta.
Iceland (58%), Lithuania (39%) and Malta (42%) reported the largest proportion of cases of latent syphilis, when the virus is still alive in the body, but without any signs or symptoms of the infection.
Syphilis cases soared in Europe over the last decade and became, for the first time since the early 2000s, more common in some countries than new cases of HIV, according to the report.
The report puts the increase in the number of cases down to men not using condoms, an increase in the number of sexual partners, and the impact of a pill taken before sex to reduce the risk of HIV infection.
Experts believe this pill led to riskier sexual behaviour as people were no longer concerned about contracting the virus.
The rise in the use of drugs to heighten sexual pleasure and lose inhibitions and the use of apps to find sexual partners could also be behind a rise in the disease, the report said.
Left untreated, syphilis can have severe complications in men and women, including causing stillbirths and newborn deaths and increasing the risk of HIV.
Syphilis was one of the leading causes of baby loss globally in 2016.
The report comes amid a rise in STIs around the world. The World Health Organisation recently warned that a million new cases of STIs are contracted every day.