Syphilis cases have soared by 70 per cent in Europe since 2010, data shows.
A report reveals the sexually transmitted infection (STI) reached an all-time high in 2017, with 33,189 confirmed cases in 28 countries across the continent.
This is an increase of more than 13,000 from the 19,797 reported incidences in 2007.
Although an issue throughout Europe, cases of the STI more than doubled between 2010 and 2017 in five countries, including Britain.
Once considered a 'Victorian disease', some countries even saw more new cases of syphilis than HIV, the report found.
Researchers from Sweden blame unprotected sex, 'riskier behaviours among gay men' and a 'reduced fear of HIV' for the surge in syphilis, which can be deadly if untreated.
A report reveals syphilis reached an all-time high in 2017, with 33,189 confirmed cases in 28 countries across Europe. This is an increase of more than 13,000 from the 19,797 cases in 2007
The report was put together by the European Centre for Disease Prevention and Control (ECDC) in Stockholm and led by Dr Andrew Amato-Gauci, head of the HIV, STI and hepatitis programme.
'The increases in syphilis infections that we see across Europe are a result of several factors,' Dr Amato-Gauci said.
'Such as people having sex without condoms and multiple sexual partners, combined with a reduced fear of acquiring HIV,' Reuters reported.
The ECDC analysed data for 2017 from The European Surveillance System, which records the rate of infectious diseases throughout the continent.
This was compared against a previous report of theirs that looked at syphilis rates as far back as 2010.
Syphilis is a bacterial infection that is usually caught by having sex with an infected person.
It spreads through close contact with an infected sore, which usually happens during vaginal, oral or anal sex.
Infected pregnant women can pass the STI to their unborn babies, which can lead to miscarriages or stillbirths.
Syphilis can also be spread by sharing needles with an infected person.
Symptoms are not always obvious and may eventually disappear.
These could include:Small, painless sores or ulcers on the penis, vagina, anus or around the mouth Blotchy red rashes on the palms or soles of the feet Small skin growths on women's vulvas or the anus White patches in the mouth Fatigue, headaches, joint pain, fever and swollen lymph nodes
If untreated, syphilis can spread to the brain or elsewhere in the body and cause disabilities or death.
Treatment is usually an antibiotic injection into the buttocks or a course of tablets.
People can reduce their risk by using condoms during sex, a dental dam (plastic square) in oral sex and avoiding sharing sex toys.
Source: NHS Choices
The report found more than 260,000 cases of syphilis were diagnosed in Europe between 2007 and 2017.
Rates of the STI began to rise in 2011 and peaked at more than 33,000 in 2017.
Europe even had more reported cases of the Victorian STI than HIV for the first time since the early 2000s.
The problem varied between countries, with the UK, Belgium, France, Germany, Malta and the Netherlands seeing cases more than double from 2010-to-2017.
The largest increase was in Iceland, where cases went from just five in 2010 to 52 in 2017.
Iceland even ended up with the highest syphilis rate in Europe, with 15.4 people having the STI per 100,000 members of the population.
This was followed by Malta at 13.5 cases of syphilis per 100,000 people and then the UK at 11.8 per 100,000 Britons.
But in Estonia and Romania, cases more than halved.
Estonia was among the countries with the lowest syphilis