Shock figures reveal that the number of cases of syphilis in Gainsborough and the rest of Lincolnshire has more than doubled inside a year.
Now, health chiefs have launched a campaign that highlights the increased chances of contracting a sexually transmitted infection (STI) unless a condom is used during sex.
Jharna Kumbang, of Public Health England (PHE), said: “It’s always best to use a condom with new partners, and remember that a condom is just as important for oral sex.
“If changing partners frequently, then regular testing for STIs is also important.
“Treatment of syphilis is highly effective and if you are concerned you have picked up an infection through unprotected sex, get in touch with your local sexual health clinic for further advice and treatment as soon as possible.”
The latest figures on STIs show that cases of syphilis across England increased by 20 per cent between 2016 and 2017, but in Lincolnshire, the number rose by a far greater amount.
Tony McGinty, consultant in public health at Lincolnshire County Cou8ncil, said: “Historically, most syphilis cases were seen among males, particularly in men who have sex with men. But since 2016, there has been an increase in the number and proportion of heterosexual males and females.
“This is happening sporadically across Limcolnshire, and we want to try and prevent the problem getting bigger.
“We want to reach out to both men and women in long-term heterosexual relationships who have recently started having sexual contact with other partners.
“Our sexual health clinics offer testing, advice and sympathetic support for men and women in this sensitive position.”
The symptoms of syphilis are not always obvious, but can include small, painless sores or ulcers on the penis or vagina, red rashes on the hands or feet, skin growths around the anus, white patches in the mouth, tiredness and fever.
If left untreated, syphilis can spread to the brain and other parts of the body and cause long-term health problems.