The UK Health Security Agency (UKHSA) is warning about a small but significant rise in cases of antibiotic-resistant gonorrhoea.
Most cases of the sexually transmitted infection (STI) can be treated quickly, but there's growing concern over strains that can't be dealt with so easily.
Between June 2022 and May 2024, scientists working at the UKHSA identified 15 cases in England that were resistant to the antibiotic ceftriaxone, the first option drug used to treat the condition in the UK.
That compares to just nine cases that had ever been found before 2022.
If left untreated, gonorrhoea can cause major health issues, including problems with your pelvis and infertility.
So far all cases found were picked by heterosexual people. Most were in their 20s and got the infection abroad.
But some of the UKHSA's top epidemiologists say even though the numbers are small, they still need a major response.
Dr Hamish Mohammed is one of them and told BBC Newsbeat: "One case is a case too many."
"Antibiotic-resistant gonorrhoea is a worldwide public health concern," he says.
He says it's vital to limit any transmission in the UK so gonorrhoea remains a treatable infection.
But he adds that the UK has a unique and effective way of getting a "comprehensive data to look at trends in STIs".
From the swab to the lab
The UKHSA is working to process samples from across the country, monitoring different strains and anything individual clinics can't fully diagnose.
It also means cases can be quickly identified so sexual partners can be traced and tested to stop further spread.
They have more data to look through than ever before. In 2023, there were more than 85,000 gonorrhoea cases reported in England, the highest number since records began.
That's the job of people like 24-year-old Zilan Ersoy, one of the biomedical scientists working at a high-security UKHSA lab in north London.
She says describing what she does can sometimes make others feel squeamish, but says "it's important that we have these open conversations with our friends so they're aware and know to get tested".
The lab usually gets samples in the form of swabs which then get processed or grown in petri dishes.
"It can be a bit smelly, but it's very cool to see how the bacteria grows."
She says she always wanted to work in this area as microbiology always fascinated her.
Zilan says it's vital that people know how to protect themselves too.
"I think it's very important we have these conversations about sexual health."
Her advice is to make sure you're using condoms, particularly when having sex with new partners, and to get tested regularly.
Gonorrhoea: quick facts
- Gonorrhoea is easily passed from person to person through unprotected sex
- Around 1 in 10 infected men and almost half of infected women do not experience any symptoms
- The infection can be passed from a pregnant woman to her baby, and without treatment, can cause permanent blindness for a newborn baby
- It is NOT spread by non-sexual contact like hugging
- It is NOT transmitted through surfaces and materials like toilet seats, towels, cups or plates
- If you've had successful treatment for gonorrhoea before, you can still catch it again
Source: NHS
There's more information and advice on this NHS webpage.
Syphilis cases on the up again
Zilan's advice above for good sexual health applies not just to protecting against gonorrhoea, but all sexually transmitted infections.
The UKHSA has also released the latest data on rates of syphilis which shows cases are still on the rise.
The disease can cause serious and potentially life-threatening damage to the brain, heart and nerves if not treated. This new data shows an increase of 9.4% year-on-year (from 8,693 cases detected in 2022, to 9,513 detected in 2023).
While the highest rates are still among gay and bisexual men, the biggest proportional increase is in heterosexual people.
The UKHSA says it wants more doctors to consider the disease and be aware of its symptoms.
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