Burnet Institute researchers have joined their peers in our nation’s capital for the Australasian HIV/AIDS Conference and Sexual Health Conference.

The Institute was well represented at both conferences with a number of staff presenting their research.

Caroline Van Gemert Anna Bowring, and Alyce Vella were among those who presented at the Sexual Health Conference. Here is an overview of the research they spoke about.

More strategies needed to increase testing for Chlamydia among young people, particularly men

Nearly half a million chlamydia test results were collected as part of a study which is part of the Australian Collaboration for Chlamydia Enhanced Sentinel Surveillance (ACCESS), established in 2008, which aims to collate information from a range of networks to provide population level Chlamydia testing and positivity rates.

Out of the tests collated, just 27 percent were men and nearly 70 percent were between the ages of 16 to 29. The tests showed men in that age bracket were more likely to return a positive chlamydia test (11.5 percent) compared to women (7.6 percent.)

Chlamydia positivity declined steadily as age increased for both women and men:
positivity rates among women aged 16-19, 20-24 and 25-29 years were 11.7 percent, 7.9 percent and 4.4percent, respectively, and positivity rates among men aged 16-19, 20-24 and 25-29 years were 14.4 percent, 12.9 percent and 8.8 percent, respectively.

Burnet Institute epidemiologist Caroline Van Gemert said these results highlight the need for strategies to increase testing among young people, particularly men.

“Chlamydia testing data are important to interpret increasing trends in notifications, however there has been no national collation of testing data beyond Medicare data in Australia,” Ms Van Gemert said.

“Without this information, we are unable to determine if an increase in cases represents an actual increase in disease or if it is a result of increased testing in the community.”

The ACCESS Laboratory Network successfully implemented the first national laboratory-based sentinel surveillance system for Chlamydia, representing 50-70% of total testing by integrating public and private laboratory data.

Male sex workers are no more at risk of sexually transmitted infections (STIs) than other men who have sex with men

The most at-risk population for HIV and other STIs are men who have sex with men and those identifying as sex workers are believed to be at greater risk.

The research compared STI testing outcomes and sexual risk practices among the two groups, through data collected from the Victorian Primary Care Network for Sentinel Surveillance (VPCNSS) from April 2006-June 2010.

Honours student Alyce Vella who led the study also found MSW are more likely to be tested for STIs compared to MSM, although both groups showed similar rates of STI diagnoses.

“Despite reporting higher rates of sexual activity, a combination of more regular STI testing and more frequent condom use among male sex workers is likely to have contributed to the similar rates of STI diagnoses,” Ms Vella said.

“More than half of MSW reported consistent condom use with any partner compared to just over 40 per cent of other men who have sex with men.

“This data can be used to inform health promotion targeting men who have sex with men and support the important role of regular STI testing in that population.”

75 percent of young people who had a positive chlamydia test didn’t have a repeat test

Burnet Institute research has found just a quarter of young people who had a positive chlamydia test at general practices returned for a repeat test, of those, 19 percent were positive.

Researchers from Burnet’s Centre for Population Health investigated repeat testing rates at general practices and family planning clinics participating in the Australian Collaboration for Chlamydia Enhanced Sentinel Surveillance (ACCESS) system. Research was conducted in collaboration with the Kirby Institute, University of New South Wales, Family Planning Organisations, and General Practice representatives.

They looked at the rate of chlamydia testing, the proportion of positive tests, and repeat testing rates following a positive chlamydia test in all 16-29 year old patients attending 25 General Practices and four Family Planning Clinics during 2008-2009.

They found that, at General Practices:
- In 2008, 2,338 (7.4 percent) patients tested for Chlamydia and of these, 175(9.1 percent) tested positive; and
- In 2009, 2,556 (7.3 percent) patients tested for Chlamydia and of these 161 (8.0 percent) tested positive.
- Of 285 patients with a positive chlamydia test in Jan 2008- Aug 2009, 25 percent had a repeat test within 1.5-4 months; 11 (19%) repeat tests were positive.

At Family Planning Clinics:
- In 2008, 2,306 (37.6 percent) patients tested for chlamydia and 194 (8.5 percent) tested positive;
- In 2009, 2,176 (33.6 percent) patients tested for chlamydia and 195 (9.0 percent) tested positive.
- Of 310 patients with a positive chlamydia test in Jan 2008- Aug 2009, 12 percent had a repeat test within 1-4 months; 5 (13 percent) repeat tests were positive.

Associate Professor Margaret Hellard, Head of the Centre for Population Health said the proportion of young people undergoing yearly testing for chlamydia infection is low and in addition, positivity at the repeat test is high.

“Based on previous research, the majority of repeat positive tests are due to reinfection by an untreated sexual partner, but may also indicate treatment failure,” Associate Professor Hellard said.

“These findings emphasise the importance of a repeat test at three months and for clear, consistent repeat testing guidelines across all primary healthcare sectors. Strategies are needed to increase repeat testing and prevent reinfection.”

Chlamydia infection is widespread in young people, and commonly causes no symptoms. Health guidelines recommend annually testing all young people when attending a health clinic, in order to detect and treat infection, reduce the likelihood of reproductive complications and prevent the further spread of disease.

Even after treatment, reinfection is common and increases the risk of reproductive complications, including infertility. Repeat testing at 3 months after positive diagnosis is recommended, although some guidelines advise that up to 6 or 12 months is also acceptable