An Austrian man caught drug-resistant super-gonorrhoea after having unprotected sex with a sex worker in Cambodia, say reports.
The unidentified man, in his 50s, was on holiday in April when he slept with the woman.
When he returned home five days later he reportedly experienced a burning pain while urinating and discharge from his penis.
Tests determined he had the STI and he was given a course of antibiotics.
While his symptoms disappeared, he was still testing positive, meaning the treatment had failed.
Doctors have said this strain is "extensively drug-resistant" and have warned it could make gonorrhoea untreatable if it was allowed to spread, according to a report
Dr Sonja Pleininger of the Austrian Agency for Health and Food Safety, the lead author of the report, said such strains "pose a major global public health threat", reports Mail Online.
She said: "If such strains manage to establish a sustained transmission, many gonorrhoea cases might become untreatable."
The authors also said new medications targeting the gonorrhoea bacteria or the creation of a vaccine are crucial to curbing drug-resistant strains.
The man was given a week-long course of amoxicillin-clavulanic acid, a combination antibiotic treatment and later tested negative.
The Cambodian sex worker has not been traced, meaning this could happen again, the experts who detailed the man's case said in the journal Eurosurveillance.
Gonorrhoea is the second most common STI in the UK, with almost 60,000 people catching it each year.
Symptoms can include a thick green or yellow discharge from the vagina or penis, and pain when urinating.
If it is left untreated it can lead to serious complications such as infertility and potentially life-threatening pelvic inflammatory disease in women.
In March, the antibiotic-resistant 'super strain' was found in several regions in the UK.
Three cases of sexually transmitted infection were confirmed by the UK Health Security Agency, in addition to a case announced in December 2021.
STIs reach their peak in London, which is not surprising given the population mass of the area.
It comes as gonorrhoea has been developing resistance to a number of antibiotics, which is known as antimicrobial resistance.
Doctors in the UK used to prescribe ciprofloxacin, and as of 2005 it was no longer recommended because the bacteria had become resistant.
In 2011, cefixime was also dropped for the same reason.
The Austrian man had displayed resistance to azithromycin, which is one of the two main antibiotics used to treat gonorrhoea in Europe.
