A strain of gonorrhoea that appears to be mutating into a drug resistant form has reached New Zealand.

The World Health Organisation has revealed that several countries, including Australia and the United Kingdom, are reporting cases of the sexually transmitted disease's resistance to cephalosporin antibiotics – the current cure.

It has now been detected in New Zealand.

Clinical microbiologist Sally Roberts, from Auckland District Health Board, was the one to pick it up here and watch prevalence increase since July last year.

"We've been seeing mutations, suggesting it is becoming less susceptible to the antibiotics. It's clearly been introduced into New Zealand somehow."

The New Zealand cases, mainly in the gay and bisexual population of Auckland and Wellington, were of the same gonorrhoea strain on which WHO is calling for urgent action.

WHO wants greater vigilance on the correct use of antibiotics and urgent research into alternative treatment since no other drug is currently available.

Dr Roberts had already been working with sexual health doctors and the New Zealand Aids Foundation to raise awareness.

Gonorrhoea had already become resistant to past treatments, like penicillin. If it was to do the same with the current antibiotic – an intra-muscular injection – treatment could become so difficult that patients could need hospitalisation, Dr Roberts said.

"If this becomes the predominant strain in our community, there will be people who have untreatable gonorrhoea."

Gonorrhoea can infect the penis, rectum and throat – often showing no symptoms. People should not feel panicked, but anyone thinking they may have been infected are asked to get tested to avoid spreading the mutating strain.

WHO figures show about 106 million people are diagnosed with the disease each year.

A Health Ministry spokesman said the antibiotic Ceftriaxone was still an effective treatment in New Zealand right now. But gonorrhea trends were being monitored to detect early the development of resistance in gonorrhea.