KEY POINTS:
The number of people suffering from gonorrhoea has risen sharply, particularly among the young, a medical study has shown.
Antibiotic-resistant cases are increasing in Auckland as the sexually transmitted disease charts a steady increase in New Zealand.
A study conducted by two doctors at the Auckland Sexual Health Service found that a third of 204 gonorrhoea cases at its clinics were resistant to treatment with the antibiotic ciprofloxacin.
The study, which is published in the latest Medical Journal, also notes that New Zealand has relatively high rates of the disease compared with other developed countries, with surveillance data from the Auckland, Waikato and Bay of Plenty regions showing a steady annual increase over the last five years.
In Auckland, the rate was 45 cases per 100,000 people in the first quarter of 2006, compared to around 27 cases per 100,000 over the same period in 2001.
In the Bay of Plenty, incidence rates over the same period have risen from 14 to 38 per 100,000.
A similar rise has been recorded in Waikato.
Roughly one person in every 1000 aged 20 to 24 in Auckland had the disease in the first quarter of 2006, with 53 per cent of infections occurring in people aged 15 to 24.
The study group's incidence rate of ciprofloxacin-resistant gonorrhoea (33 per cent) was higher than overall lab results for Auckland (19 per cent), which the authors attributed to the Auckland sexual health clinics serving a "high-risk population".
The rate of antibiotic-resistant gonorrhoea was hovering around 3 per cent in the 1990s until an outbreak in South Auckland in 2001 raised the prevalence to over 10 per cent.
For the study, physicians Sunita Azariah and Nicky Perkins looked at patients diagnosed with the disease at their clinics between September 2003 and March 2004.
Of those, 50 per cent of cases were in patients under 25. Patients of Maori and Pacific ethnicity made up nearly half of all cases. Eighty per cent were exclusively heterosexual. More than half (58 per cent) never used condoms.
Dr Helen Roberts, the Family Planning Association's research manager for the northern region, said the increase in ciprofloxacin resistance was quite worrying, as the alternative, ceftriaxone, was quite difficult to access in primary care.
"We can only hope that we don't start to get ceftriaxone-resistance because then we really have a problem."
It was also worth noting that 50 per cent of the cases were in people over 26, she said.
The message was simple, Dr Roberts added - use condoms or have regular checks when changing partners.
Gonorrhoea
Sexually transmitted disease (STD) caused by the neisseria gonorrhoeae bacteria.
In men, symptoms include a burning sensation when urinating, or a white, yellow or green discharge. Painful or swollen testicles are also an occasional symptom.
In women, symptoms are often mild or even unnoticeable, but can include a painful or burning sensation when urinating, or increased vaginal discharge.
Left untreated, the disease can cause infertility in both sexes. It can also be life-threatening if it spreads to the blood or joints.