Hidden STI affects around 500,000 Britons – but fewer than one in five of us have ever heard of it

Fewer than one in five Britons have heard of a sexually transmitted infection that affects around 500,000 people, a survey suggests.

Mycoplasma genitalium, or Mgen, is caused by a bacterium which infects the urinary and genital tracts of both men and women via penetrative sex.

It is estimated that between one and two per cent of Britons aged 16 to 44 are affected.

The bacterial infection can cause pain when urinating, itching and bleeding after sex in women, and can lead to fertility problems if untreated.

But a poll of 500 people in the UK by Lloyds Pharmacy found that just 15 per cent had heard of Mgen, with nine in ten of saying they would not feel confident in identifying the symptoms.

‘Testing for Mgen isn’t routine at STI clinics so they may only test for it if you have symptoms or if you’ve raised it as a concern,’ says Dr Neel Patel, a GP for Lloyds Pharmacy.

Eight in ten men and half of women will have no symptoms from the infection but can request a test if they’re concerned that they have caught it from a partner.