Mycoplasma genitalium
The study found that women carrying MG were more likely to report bleeding after having sex Media for Medical/UIG via Getty Images

Researchers have said that hundreds of thousands of people in Britain could be infected with a little known sexually transmitted infection. The disease, Mycoplasma genitalium, is said to be transmitted through unsafe sex.

According to a study published in the International Journal of Epidemiology, the disease also known as MG has few symptoms, but can cause urethritis, cervicitis, pelvic inflammation and female infertility. It was first identified in the 1980s, however, there was a debate on whether or not the disease was a sexually transmitted infection (STI).

Nigel Field, a consultant clinical epidemiologist at Public Health England (PHE), who worked on the study, said the findings provide strong evidence MG is an STI, with people who reported more than four sexual partners having a higher rate of carrying the infection.

''MG is a bacterium that was present in around 1% of the general population aged 16 to 44 years, who had reported at least one sexual partner,'' he said.

The study found that women carrying MG were more likely to report bleeding after having sex. However, over 90% of men and more than half of the women in the study did not report any symptoms. "It may be that MG does not cause illness in all individuals in whom the infection is detected. Laboratory testing for MG is not yet widely available in the UK,'' he added.

''PHE has recently established national surveillance to monitor diagnoses of MG from any clinics undertaking testing and will continue to gather public health data on MG to inform policy on infection control. As for all STIs, prevention measures promoting increased condom use and a reduction in sexual risk behaviours are likely to play an important role in efforts to control MG."

Meanwhile, Dr Pam Sonnenberg, an STI expert at University College London and the lead author of the paper, said: "These findings suggest that only testing those who are currently symptomatic would miss the majority of infections. However, further research is needed to understand the clinical implications of infection and possible longer-term complications.'

"This information, together with information on resistance patterns to guide antibiotic choice, will inform recommendations on how to test for and manage MG infection."