Chlamydia prevention indicators for Australia: review of the evidence from New South Wales

Background: Annual notifications of chlamydia (Chlamydia trachomatis) diagnoses have increased steadily in Australia in the last decade. To guide public health programs, we developed 10 national chlamydia prevention indicators and report on each indicator for New South Wales (NSW). Methods: Using systematic methods, we reviewed the literature to report on the 10 health and behaviour indicators for 15- to 29-year-old heterosexuals in NSW from 2000. We included data with two or more time points. Results: Chlamydia notification rates (Indicator 1) in 15- to 29-year-olds have increased by 299%, from 237 per 100 000 population in 2001 to 946 per 100 000 population in 2010; and the percent of 15-to 34-year-olds with an annual Medicare-rebated chlamydia test (Indicator 2) increased by 326%, from 1.9% in 2001 to 8.1% in 2010. Since 2004, sentinel surveillance showed a 28% increase in chlamydia prevalence (Indicator 3) in 15- to 29-year-old females tested at their first sexual health service visit (from 8.5% in 2004 to 10.9% in 2010) but no significant increase in males. No NSW-specific chlamydia incidence (Indicator 4) was available. Pelvic inflammatory disease hospitalisation separations rate decreased from 0.58 per 1000 in 2001 to 0.44 per 1000 in 2010 in 15- to 29-year-old females (Indicator 5). Secondary school surveys in 2002 and 2008 showed chlamydia knowledge increased in males. The sexual risk-taking behaviour of young people remained unchanged (Indicators 6-10). Conclusions: Although notifications have risen steeply, the modest increase in chlamydia prevalence maybe a more realistic reflection of transmission rates. Strategies are needed to increase testing and to modify sexual risk behaviour. Crucial gaps in epidemiological data were identified.