Report sheds light on STI rates
The recently published Report on Testing Data for Notifiable Sexually Transmissible Infections and Blood-borne Viruses in Western Australia showed that from 2009 to 2011, chlamydia and gonorrhoea test positivity rates increased more than the testing rates for these diseases. This indicates that increased chlamydia and gonorrhoea notification rates are due not just to increased testing but also to increased disease transmission and/or better targeted testing of groups with higher disease prevalence.
In Western Australia, chlamydia notification rates trebled between 2002 and 2011. Rates were highest among people aged 15 to 24 years, particularly those from remote regions (Goldfields, Kimberley and Pilbara). Since 2005, the Western Australian Department of Health has conducted annual mass media campaigns to raise young people's awareness of chlamydia, and promote chlamydia testing and condom use. In addition, sexual health teams were established in Western Australia's remote regions to increase testing and improve clinical and public health management of sexually transmitted infections (STIs).
De-identified laboratory testing data for chlamydia, other STIs and blood-borne viruses (BBVs) were obtained from 5 of the 7 WA pathology providers to assess the impact of disease control programs and assist in the interpretation of disease notification rates.
Between 2009 and 2011, the WA chlamydia testing rate increased by 6% (53 to 56/1000 population) while the test positivity rate increased by 22% (5.4 to 6.6%) and the notification rate by 26%. The testing rate in 15 to 24 year old females was 3 times that of the males; both increased only marginally over time: males by 8% (71 to 77/1,000) and females by 4% (223 to 231/1,000). However, notification rates in males and females increased by 23% and 31% respectively, and chlamydia test positivity also increased from 13% to 15% in males, and from 8% to 10% in females. Similar trends were observed for gonorrhoea.
Syphilis testing rates in WA increased marginally by 2% (34.8 to 35.5/1000 population) in WA between 2009 and 2011. Although the test positivity rate remained low, it increased significantly (1.0 to 1.4%) over this period. However, the notification rate increased 36%. Increases in testing rates and notification rates in males (but not in females) reflects the ongoing increase in transmission among men who have sex with men (MSM).
Despite the Royal Australian College of General Practitioners' recommendation that annual chlamydia testing be offered to all 15 to 24 year olds, testing rates in this group were lower than expected, even in remote regions serviced by dedicated STI teams. Improved strategies are needed to encourage chlamydia testing among young people.