HEALTH officials in the North-East are worried about a big increase in cases of gonorrhoea, a sexually transmitted disease which is becoming resistant to treatment.

The region saw a 41 per cent surge in cases of gonorrhoea last year, almost twice as big as the 21 per cent increase seen nationally.

New figures from Public Health England revealed that a total of 21,507 new cases of sexually transmitted infections (STIs) were diagnosed in the North-East last year compared with 20,602 in 2011.

The STI which increased the most was gonorrhoea, with cases rising from 749 in 2011 to 1,055 in 2012.

Doctors are concerned because of the development of strains of the disease which are resistant to antibiotic treatment.

In the North-East, chlamydia remains the most commonly diagnosed STI with 12,056 new cases diagnosed last year.

Those aged under 25 experienced the highest STI rates and young adults are being advised to get tested for chlamydia annually or on change of sexual partner.

New diagnoses of syphilis also increased by 22 per cent in the region over the period although cases of herpes stabilised and warts decreased.

Dr Kirsty Foster, sexual health lead for PHE in the North-East said: "These latest figures show that, in common with the rest of the UK, poor sexual health continues to be a serious problem in the North-East.

"Annual cases of gonorrhoea have almost doubled in the North-East since 2009. This continued rise is a particular cause for concern, as we know drug resistance is emerging and we can no longer rely on treatment alone.

"These are all preventable infections and it's crucial that we continue to communicate messages about safe sex, including condom wearing, and the importance of getting checked out if you've had unprotected sex with a new partner."