The strain is “highly resistant” to the antibiotic azithromycin, meaning medics are relying on a second drug, ceftriaxone, to treat it.
Public Health ngland (PHE) urged people to use condoms with new or casual partners to cut the risk of catching the disease.
If untreated, gonorrhoea can result in severe complications and lead to infertility or septicaemia in rare cases.
Dr Gwenda Hughes, head of PHE’s Sexually Transmitted Infections (STI) section, said: “Fortunately, the current outbreak strain can still be treated with ceftriaxone... If strains of gonorrhoea emerge that are resistant to both azithromycin and ceftriaxone treatment options would be limited as there is currently no new antibiotic available to treat the infection.”
PHE said yesterday there were 34 confirmed cases since November 2014.
Since September 2015, 11 cases have been confirmed in the West Midlands and in the South of England, five of them in London.
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.