An outbreak of highly drug-resistant "super-gonorrhoea" is sweeping across Britain and could become untreatable, medics fear. A national alert was triggered by Public Health England last September after the rare strain of the sexually transmitted superbug was detected in 15 people. However, Public Health England (PHE) is understood to have acknowledged that efforts to contain the spread have been of "limited success".

The alert comes after Chancellor George Osborne warned resistance to antibiotics will become "an even greater threat to mankind than cancer" without global action. PHE said an increase in cases of super-gonorrhoea was a "further sign of the very real threat of antibiotic resistance to our ability to treat infections".

The British Association for Sexual Health and HIV issued an alert to clinicians urging them to follow up cases of high level drug resistant gonorrhoea and trace their sexual partners. Its president, Dr Elizabeth Carlin, said: "The spread of high level azithromycin-resistant gonorrhoea is a huge concern and it is essential that every effort is made to contain further spread.