Risk factors and characteristics of patients with gonorrhoea presenting to Auckland Sexual Health Service, New Zealand.

Objective: A case-control study of patients with gonorrhoea presenting to Auckland Sexual Health Service was carried out to determine specific risk factors and to look more closely at the transmission of ciprofloxacin-resistant Neisseria gonorrhoeae in the Auckland region.

Methods: Patients who tested positive for gonorrhoea during a 6-month time period from September 2003 till March 2004 were included in the study. A control group was selected from patients who presented during the same time period but who had negative sexually transmitted infection (STI) screens. A selection of N. gonorrhoeae isolates were sent to ESR for typing by pulsed-field gel electrophoresis (PFGE).

Results: 204 cases of gonorrhoea were identified during the study period; 50% of the diagnosed cases were in people aged less than 26 years. Gonococcal infection was strongly associated with being of either Māori or Pacific ethnicity (p<0.001). A history of consistent condom use was found to lower the risk of acquisition of gonorrhoea (p=0.009). Thirty-three percent of cases had ciprofloxacin-resistant gonococcal infection and the majority of these acquired their infection in New Zealand (88%). Comparison of PFGE genotyping data with results from an audit in 2001 indicated that genetic diversity amongst ciprofloxacin-resistant isolates has increased significantly.

Conclusions: The incidence of gonorrhoea in the Auckland population is steadily rising, with the main risk factors being age under 25 and being of Māori or Pacific ethnicity. Genetic diversity amongst ciprofloxacin-resistant isolates is increasing, thus indicating high levels of endemic infection. Urgent action needs to be taken to control the current gonorrhoea epidemic in Auckland and more research is required to investigate reasons for ethnic differences in disease incidence.