Key to chlamydia control is better management, not screening
Stark results from a new study on chlamydia screening have prompted calls for a greater emphasis on management and re-infection prevention.
The Australian study, published in The Lancet, did not find a significant reduction in the overall proportion of the population contracting chlamydia in a randomised group of sexually active peopled aged 16 to 29 years undergoing opportunistic testing compared to controls.
Lead researcher, Professor Jane Hocking, from the Centre for Epidemiology and Biostatistics at the University of Melbourne, told doctorportal that “our recommendations are that GPs should continue to test young men and women for chlamydia in line with clinical guidelines, but we need a greater emphasis on the management of chlamydia once diagnosed to reduce the risk of repeat infection.”
“This includes getting sexual partners tested and treated, and making sure that people treated for chlamydia are re-tested again 3 months later, as guidelines recommend, to detect any repeat infections early to minimise the risk of complications arising from infection.”
Research was needed to determine the effectiveness of a chlamydia screening program
Professor Hocking said that “chlamydia has been the most commonly diagnosed bacterial STI over the last 15 years and if left untreated, about 10% of cases of chlamydia in women will develop into pelvic inflammatory disease (PID) which increases a woman’s risk of future infertility”
She said that due to this, a number of high-income countries including Australia, have recommended screening for young adults.
“However, there isn’t any clear evidence that introducing a chlamydia screening program in general practice would reduce the burden of chlamydia in the population.”
This prompted the Australian government to fund this trial to determine whether chlamydia screening in general practice was effective at quelling chlamydia rates.
Chlamydia is a common infection – so why doesn’t opportunistic screening work?
The study was a cluster-randomised controlled trial. Clusters were rural towns in Australia with a minimum of 500 women and men aged 16–29 years, and no more than six primary care clinics.
Each cluster was randomised to either a clinic-based chlamydia testing intervention or to continue usual care. The intervention included computerised reminders to test patients, an education package, payments for chlamydia testing, and feedback on testing rates
Overall the findings, in conjunction with evidence about the feasibility of sustained uptake of opportunistic testing in primary care, indicated that sizeable reductions in chlamydia prevalence might not be achievable. Professor Hocking said the probable reason for this was due to testing rates not reaching high enough levels, for a long enough time.
“Previous modelling suggests that we need to test over 20% of young people for 10 years to reduce prevalence by 65%. In our trial, testing rates reached over 20% per year, but were only at this level for one year.”
Professor Hocking said that the trial aimed to demonstrate the likely impact of achievable levels of chlamydia testing in general practice.
“General practice is increasingly busy and young people, in particular young men, just don’t visit the GP often enough, or when they do attend, chlamydia testing isn’t discussed because of the time pressures or other clinical needs.”
“So, it is difficult to reach those target testing levels that are likely to make an impact on the burden of chlamydia in the population. Nevertheless, our trial increased chlamydia testing by over 150% in the intervention group.”
Call to focus more on improving chlamydia management
Professor Hocking highlighted that better case management will reduce infection rates and reduce the risk of complications arising from infection.
“The aim of chlamydia control is really to reduce the reproductive health complications associated with chlamydia – and if PID can be prevented, then that would reduce the risk of infertility in women.”
A key factor that results in chlamydia-associated PID is re-infection. In fact, having two or more past chlamydia infections can increase a woman’s risk of PID by up to 4-fold.
“About 15-20% of young adults will acquire a repeat chlamydia infection within 6 months of treatment for a past infection – so if we can reduce repeat infection, this suggests that we will reduce the risk of PID”, Professor Hocking said.