Reducing the burden of chlamydia in Australia
Chlamydia remains Australia’s most notified bacterial sexually transmissible infection (STI), prompting the authors of a Perspective published by the Medical Journal of Australia today to call for comprehensive follow-up of cases and contacts to reduce the risk of complications.
“From 2014 to 2018, the overall number and rate of chlamydia notifications rose by 21% and 15% respectively,” wrote the authors, led by Dr Stephanie Munari, a PhD candidate with the Sexual Health Unit at the Melbourne School of Population and Global Health, and Senior Research Officer at the Burnet Institute.
“Most new chlamydia infections are occurring among young people aged 15–29 years, and in 2019, women aged 15–24 years old recorded higher notification rates per 100 000 population compared with similarly aged men.
“In addition to people with female reproductive organs and young people aged 15–29 years, chlamydia is also disproportionately high among Aboriginal and Torres Strait Islander people, people living in remote and very remote areas, those with greater socio-economic disadvantage, and among gay and bisexual men.
“People who are pregnant are also a priority population, where chlamydia infection is associated with miscarriage, stillbirth, preterm birth, low birth weight, and postpartum infections in the mother and/or newborn.”
Current Australian guidelines recommend testing for chlamydia in people aged under 30 years who are sexually active, those who are pregnant, those who are requesting an STI check, and those who have had a partner change or an STI in the past 12 months or a sexual partner with an STI. For those who test positive, retesting is recommended at 3 months after treatment to identify possible reinfection. Tests can be self-collected by the patient, and the treatment of a positive case consists of a 7-day course of doxycycline as first line therapy or a single dose of azithromycin.
Where are the gaps?
Improve chlamydia retesting: “One gap is the low rates of chlamydia retesting after treatment for a prior infection. Reinfection rates are high with about 20% of young women being reinfected after treatment. Reinfections lead to ongoing transmission and increase a woman’s risk of reproductive complications. Modelling suggests that earlier testing and retesting at the recommend 3 months after diagnosis may increase the window of opportunity for treatment and thus reduce the likelihood of reproductive complications.”
Improve diagnosis of pelvic inflammatory disease (PID): “Another gap in chlamydia management is the underdiagnosis of PID in primary care settings. About 20-30% of PID in the community is due to chlamydia infection. If untreated, around 17% of chlamydia infections in women will progress to PID, with the risk of PID increasing by 20% with each repeat chlamydia infection. Clinical diagnosis can be challenging due to the diverse range of clinical presentations and many GPs experience barriers to conducting pelvic examinations that would support a PID diagnosis.”
Move away from asymptomatic screening: “The focus of chlamydia control measures is shifting away from the promotion of asymptomatic screening towards improved case management to reduce the complications of infections. Consideration must also be given to the possible harms from asymptomatic screening, including increasing the potential for antimicrobial resistance due to the inappropriate use, and overuse, of antibiotics, psychological distress associated with false positive diagnoses, and adverse impacts on microbiota. If Australia is to reduce its burden of disease from chlamydia, an increased focus on case and partner management will be required.”
Enhance partner notification and management: “Notifying, testing and treating sexual partners from the previous 6 months can also help to interrupt ongoing transmission and reduce the risk of reinfection and complications. Patient-delivered partner therapy can be an effective way to both treat the partners and reduce reinfection in the index case.”
Embrace new testing approaches: “The increasing use of digital health technology offers an enticing opportunity for reaching a population with high technical literacy skills. Online primary care consultations that use telehealth, the increasing use of home sampling kits for posting back to a laboratory, electronic prescriptions, and trials of online sexual health hubs might help to overcome identified barriers to accessing traditional sexual health service delivery, including concerns about privacy, confidentiality, and perceived stigma.”
Munari and colleagues concluded that “comprehensive follow-up of cases and contacts to reduce the risk of complications is required” to reduce the burden of chlamydia in Australia.
“When chlamydia is detected, retesting at 3 months post treatment for reinfection and performing thorough partner tracing and management can help interrupt transmission and reduce the risk of reinfection and reproductive complications,” they wrote.
“Further studies investigating the timing of testing and treatment of chlamydia infections on the progression to reproductive complications will help guide public health strategies to further reduce the burden of chlamydia in Australia.”