Seasonal variation in gonorrhoea incidence among men who have sex with men

Background After reviewing urethral gonorrhoea cases among men who have sex with men (MSM) at the South Australia Specialist Sexual Health (SASSH) in Adelaide, Australia, we noticed peaks of gonorrhoea among MSM occurred predominantly in the first quarter of the year (January-March). The aim of this study was to formally test this hypothesis against data from a similar period at three sexual health services, one each in Adelaide, Melbourne and Sydney. Methods: This study was a retrospective analysis of computerised records at the three Australian sexual health services. Potential risk factors for urethral gonorrhoea among MSM were also reviewed at the SASSH. Results: More peaks of gonorrhoea cases were observed in the first quarter of the year in Adelaide and Sydney and in the second and fourth quarter in Melbourne. Factors independently associated with urethral gonorrhoea at the SASSH were being a young MSM, especially those aged 25-29 (odds ratio (OR) 2.66, 95% confidence interval (CI): 2.00-3.54), having more than one sexual partner (OR 1.71, 95% CI: 1.43-2.04), having had sex interstate and overseas (OR 1.52, 95% CI: 1.06-2.17), and presenting in the first quarter (OR 1.30, 95% CI: 1.10-1.55). Conclusion: Our data suggest that gonorrhoea among MSM occurs in a seasonal pattern, particularly late summer into early autumn. This has implications for the provision of health services over the year and for the timing of health promotion activities.