The cost effectiveness of screening for genital Chlamydia trachomatis infection in Australia

Evaluation of Chlamydia trachomatis screening from the perspective of health economics: a systematic review

Background

Most Chlamydia trachomatis (CT) infections are asymptomatic. The infection can persist and lead to severe sequelae. Therefore, screening for CT can primarily prevent serious sequelae.

Aim

To systematically evaluate CT screening from the perspective of health economics, summarize previous findings from different target populations, and make practical recommendations for developing local CT screening strategies.

Methods

PubMed, Web of Science, Embase, Cochran Library, and National Health Service Economic Evaluation Database (Ovid) were searched from January 1, 2000, to March 4, 2023. Studies reporting the cost-effectiveness, cost-benefit, or cost-utility of CT screening were eligible to be included. A narrative synthesis was used to analyze and report the results following the PRISMA guidelines. The Consensus on Health Economic Criteria (CHEC) list was used to assess the methodological quality of included studies.

Results

Our review finally comprised 39 studies addressing four populations: general sexually active people (n = 25), pregnant women (n = 4), women attending STD and abortion clinics (n = 4), and other high-risk individuals (n = 6). The total number of participants was ~7,991,198. The majority of studies assessed the cost-effectiveness or cost-utility of the screening method. The results showed that the following screening strategies may be cost-effective or cost-saving under certain conditions: performing CT screening in young people aged 15-24 in the general population, military recruits, and high school students; incorporating CT screening into routine antenatal care for pregnant women aged 15-30; opportunistic CT screening for women attending STD and abortion clinics; home-obtained sampling for CT screening using urine specimens or vaginal swab; performing CT screening for 14-30-year-old people who enter correctional institutions (i.e., jail, detention) as soon as possible; providing CT screening for female sex workers (FSWs) based on local incidence and prevalence; adding routine CT screening to HIV treatment using rectal samples from men who have sex with men (MSM).

Conclusion

We found that CT screening in general sexually active people aged 15-24, military recruits, high school students, pregnant women aged 15-30, women attending STD and abortion clinics, people entering jail, detention, FSWs, and MSM has health economic value. Due to the different prevalence of CT, diversities of economic conditions, and varying screening costs among different populations and different countries, regions, or settings, no uniform and standard screening strategies are currently available. Therefore, each country should consider its local condition and the results of health economic evaluations of CT screening programs in that country to develop appropriate CT screening strategies.

A Web-Based Sexual Health Intervention to Prevent Sexually Transmitted Infections in Hong Kong: Model-Based Cost-Effectiveness Analysis

BACKGROUND

Sexually transmitted infections (STIs) remain a significant public health concern, particularly among young adults, and Chlamydia trachomatis (CT) infections are the most common STIs in young women. One of the most effective ways to prevent STIs is the consistent use of condoms during sexual intercourse. There has been no economic evaluation of the interactive web-based sexual health program, Smart Girlfriend, within the Chinese population.

OBJECTIVE

This study aimed to evaluate the long-term cost-effectiveness of Smart Girlfriend in preventing STIs in the Chinese population. The evaluation compared the program with a control intervention that used a 1-page information sheet on condom use.

METHODS

A decision-analytic model that included a decision tree followed by a Markov structure of CT infections was developed since CT is the most prevalent STI among young women. The model represents the long-term experience of individuals who received either the intervention or the control. One-way and probabilistic sensitivity analyses were conducted. The main outcomes were the number of CT infections and the incremental cost as per quality-adjusted life year (QALY).

RESULTS

A cohort of 10,000 sexually active nonpregnant young women initially entered the model in a noninfectious state (ie, "well"). In the base-case analysis, the implementation of the Smart Girlfriend program resulted in the prevention of 0.45% of CT infections, 0.3% of pelvic inflammatory disease, and 0.04% of chronic pelvic pain, leading to a gain of 70 discounted QALYs and cost savings over a 4-year time horizon, compared to the control group. With more than 4548 users, the intervention would be cost-effective, and with more than 8315 users, the intervention would be cost saving. A 99% probability of being cost-effective was detected with a willingness to pay US $17,409 per QALY.

CONCLUSIONS

Smart Girlfriend is a cost-effective and possibly cost-saving program over a 4-year time horizon. This result was particularly sensitive to the number of website users; launching the website would be cost-effective if more than 4548 people used it. Further work is warranted to explore if the findings could be expanded to apply to women who have sex with women and in the context of other STIs.

TRIAL REGISTRATION

ClinicalTrial.gov NCT03695679; https://clinicaltrials.gov/study/NCT03695679.

Chlamydia-related knowledge, opinion to opportunistic testing, and practices of providers among different sexually transmitted infections related departments in hospitals in Shenzhen city, China

BACKGROUND

Chlamydia trachomatis (CT) infection could lead to seriously adverse outcomes if left untreated. This study aimed to determine CT-related knowledge, opinion to testing, and practices of providers among different sexually transmitted infections (STI) related departments in hospitals in Shenzhen city, China, and also to explore the differences in these responses.

MATERIALS AND METHODS

From 1st April 2018 to 15th April 2018, a cross-sectional study was conducted in Shenzhen and 64 of 66 hospitals agreed to participate in this study. In the hospital sites, all the providers from the department of obstetrics and gynecology, department of dermatology and venereology, department of urology, and anorectal surgical department were recruited. A structured paper-based questionnaire was used to obtain data on CT-related information.

RESULTS

A total of 355 providers from 64 hospitals participated in the current study. Compared to providers from the department of dermatology and venereology, those from the department of obstetrics and gynecology (OR = 0.31, 95% CI 0.16-0.62), department of urology (OR = 0.32, 95% CI 0.16-0.65), and anorectal surgical department (OR = 0.25, 95% CI 0.09-0.71) were less likely to identify that "Be in a long-term mutually monogamous relationship with a partner who has been tested and has negative STI test results." is an appropriate way for a sexually active person to reduce risk of getting CT. Also, those from the department of obstetrics and gynecology (OR = 0.45, 95% CI 0.23-0.87) were less likely to identify that "Use latex condoms the right way every time you have sex" is another appropriate way. A high proportion of providers agreed that all sexually active patients attending to their department should be screened regularly (77.1%), and they are willing to offer opportunistic CT screening (96.0%). Only 11.4% of respondents correctly identified that the appropriate time frame of the CT retesting is three months.

CONCLUSIONS

Providers among STI-related departments in hospitals showed a very high willingness to offer opportunistic CT screening. However, this study showed important gaps in providers' knowledge and practices in China, targeted training in CT-related knowledge and practice is urgently needed.

Assessing the costs and outcomes of control programmes for sexually transmitted infections: a systematic review of economic evaluations

OBJECTIVE

To identify economic evaluations of interventions to control STIs and HIV targeting young people, and to assess how costs and outcomes are measured in these studies.

DESIGN

Systematic review.

DATA SOURCES

Seven databases were searched (Medline (Ovid), EMBASE (Ovid), Web of Science, PsycINFO, NHS Economic Evaluation Database, NHS Health Technology Assessment and Database of Abstracts of Reviews of Effects) from January 1999 to April 2019. Key search terms were STIs (chlamydia, gonorrhoea, syphilis) and HIV, cost benefit, cost utility, economic evaluation, public health, screening, testing and control.

REVIEW METHODS

Studies were included that measured costs and outcomes to inform an economic evaluation of any programme to control STIs and HIV targeting individuals predominantly below 30 years of age at risk of, or affected by, one or multiple STIs and/or HIV in Organisation for Economic Co-operation and Development countries. Data were extracted and tabulated and included study results and characteristics of economic evaluations. Study quality was assessed using the Philips and BMJ checklists. Results were synthesised narratively.

RESULTS

9530 records were screened and categorised. Of these, 31 were included for data extraction and critical appraisal. The majority of studies assessed the cost-effectiveness or cost-utility of screening interventions for chlamydia from a provider perspective. The main outcome measures were major outcomes averted and quality-adjusted life years. Studies evaluated direct medical costs, for example, programme costs and 11 included indirect costs, such as productivity losses. The study designs were predominantly model-based with significant heterogeneity between the models.

DISCUSSION/CONCLUSION

None of the economic evaluations encompassed aspects of equity or context, which are highly relevant to sexual health decision-makers. The review demonstrated heterogeneity in approaches to evaluate costs and outcomes for STI/HIV control programmes. The low quality of available studies along with the limited focus, that is, almost all studies relate to chlamydia, highlight the need for high-quality economic evaluations to inform the commissioning of sexual health services.

Development a rapid and accurate multiplex real time PCR method for the detection Chlamydia trachomatis and Mycoplasma hominis

BACKGROUND

Sexually transmitted diseases easily spread among sexually active people and often have no symptoms. Rapid and accurate method for detecting these infections are necessary in early stages. The traditional detection methods of them are difficult and time-consuming.

METHODS

In this study, multiplex real time PCR was optimized for rapid identification of Chlamydia trachomatis and Mycoplasma hominis in a single tube and was performed with our designed primers. The sensitivity test was carried out to designed primers with diluted genomic DNA. To defined the specificity, non STD bacteria were used as DNA template.

RESULTS

This study indicated that the developed multiplex real time PCR can be an effective alternative procedure to the conventional methods for rapid and accurate identification of C Chlamydia trachomatis and Mycoplasma hominis. Multiplex real-time PCR Results of them were checked with melting curves. The sensitivity of our designed primer by multiplex real time PCR for Chlamydia trachomatis and Mycoplasma hominis were 4.78×1010 and 8.35×1010 , respectively, Which the primers did not amplify any product from a non-STD species.

CONCLUSIONS

Multiplex real time PCR by our new primers and analysis of melting curves were successfully usable for rapid and accurate detection of Chlamydia trachomatis and Mycoplasma hominis. This assay instead of traditional culture method, has considerable potential to be rapid, accurate and highly sensitive molecular diagnostic tool for simultaneous and direct detection.

Chlamydia sequelae cost estimates used in current economic evaluations: does one-size-fit-all?

BACKGROUND

Current evidence suggests that chlamydia screening programmes can be cost-effective, conditional on assumptions within mathematical models. We explored differences in cost estimates used in published economic evaluations of chlamydia screening from seven countries (four papers each from UK and the Netherlands, two each from Sweden and Australia, and one each from Ireland, Canada and Denmark).

METHODS

From these studies, we extracted management cost estimates for seven major chlamydia sequelae. In order to compare the influence of different sequelae considered in each paper and their corresponding management costs on the total cost per case of untreated chlamydia, we applied reported unit sequelae management costs considered in each paper to a set of untreated infection to sequela progression probabilities. All costs were adjusted to 2013/2014 Great British Pound (GBP) values.

RESULTS

Sequelae management costs ranged from £171 to £3635 (pelvic inflammatory disease); £953 to £3615 (ectopic pregnancy); £546 to £6752 (tubal factor infertility); £159 to £3341 (chronic pelvic pain); £22 to £1008 (epididymitis); £11 to £1459 (neonatal conjunctivitis) and £433 to £3992 (neonatal pneumonia). Total cost of sequelae per case of untreated chlamydia ranged from £37 to £412.

CONCLUSIONS

There was substantial variation in cost per case of chlamydia sequelae used in published chlamydia screening economic evaluations, which likely arose from different assumptions about disease management pathways and the country perspectives taken. In light of this, when interpreting these studies, the reader should be satisfied that the cost estimates used sufficiently reflect the perspective taken and current disease management for their respective context.

Narrative review of the barriers and facilitators to chlamydia testing in general practice

As the cornerstone of Australian primary health care, general practice is a setting well suited for regular chlamydia testing but testing rates remain low. This review examines the barriers and facilitators to chlamydia testing in general practice. Six databases--Medline, PubMed, Meditext, PsycInfo, Scopus and Web of Science--were used to identify peer-reviewed publications that addressed barriers and facilitators to chlamydia testing in general practice using the following terms: 'chlamydia test*', 'STI test*' 'general practice', 'primary care', 'family medicine', 'barriers', 'facilitators' and 'enablers' from 1997 until November 2013. Data about the study design and key findings were extracted from the publications. A framework method was used to manage the data and organise publications into three categories -patient, general practitioner, and general practice. Key findings were then classified as a barrier or facilitator. Sixty-nine publications were included, with 41 quantitative studies, 17 qualitative studies, and 11 using mixed methods. Common barriers identified in all three groups included a lack of knowledge, awareness or training, demands on time and workload, and the social context of testing. Facilitators included the normalisation of testing, the use of nurses and other practice staff, education and incentives. Numerous barriers and facilitators to chlamydia testing in general practice have been identified. While the barriers are well studied, many of the facilitators are not as well researched, and highlight areas for further study.

The Role of the Immune Response in Chlamydia trachomatis Infection of the Male Genital Tract: A Double-Edged Sword

Chlamydia trachomatis (CT) is the most prevalent bacterial sexually transmitted infection in the world, with more than 100 million cases reported annually. While there have been extensive studies into the adverse effects that CT infection has on the female genital tract, and on the subsequent ability of these women to conceive, studies into the consequences on male fertility have been limited and controversial. This is in part due to the asymptomatic nature of the infection, where it is estimated that 50% of men with Chlamydia fail to show any symptoms. It is accepted, however, that acute and/or persistent CT infection is the causative agent for conditions such as urethritis, epididymitis, epididymo-orchitis, and potentially prostatitis. As with most infections, the immune system plays a fundamental role in the body’s attempts to eradicate the infection. The first and most important immune response to Chlamydia infection is a local one, whereby immune cells such as leukocytes are recruited to the site of infections, and subsequently secrete pro-inflammatory cytokines and chemokines such as interferon gamma. Immune cells also work to initiate and potentiate chronic inflammation through the production of reactive oxygen species (ROS), and the release of molecules with degradative properties including defensins, elastase, collagenase, cathespins, and lysozyme. This long-term inflammation can lead to cell proliferation (a possible precursor to cancer), tissue remodeling, and scarring, as well as being linked to the onset of autoimmune responses in genetically disposed individuals. This review will focus on the ability of the immune system to recognize and clear acute and persistent chlamydial infections in the male genital tract, and on the paradoxical damage that chronic inflammation resulting from the infection can cause on the reproductive health of the individual.

Valuing the health states associated with Chlamydia trachomatis infections and their sequelae: a systematic review of economic evaluations and primary studies

OBJECTIVES

Economic evaluations of interventions to prevent and control sexually transmitted infections such as Chlamydia trachomatis are increasingly required to present their outcomes in terms of quality-adjusted life-years using preference-based measurements of relevant health states. The objectives of this study were to critically evaluate how published cost-effectiveness studies have conceptualized and valued health states associated with chlamydia and to examine the primary evidence available to inform health state utility values (HSUVs).

METHODS

A systematic review was conducted, with searches of six electronic databases up to December 2012. Data on study characteristics, methods, and main results were extracted by using a standard template.

RESULTS

Nineteen economic evaluations of relevant interventions were included. Individual studies considered different health states and assigned different values and durations. Eleven studies cited the same source for HSUVs. Only five primary studies valued relevant health states. The methods and viewpoints adopted varied, and different values for health states were generated.

CONCLUSIONS

Limitations in the information available about HSUVs associated with chlamydia and its complications have implications for the robustness of economic evaluations in this area. None of the primary studies could be used without reservation to inform cost-effectiveness analyses in the United Kingdom. Future debate should consider appropriate methods for valuing health states for infectious diseases, because recommended approaches may not be suitable. Unless we adequately tackle the challenges associated with measuring and valuing health-related quality of life for patients with chlamydia and other infectious diseases, evaluating the cost-effectiveness of interventions in this area will remain problematic.

Chlamydia screening in young people as an outcome of a HEADSS; Home, Education, Activities, Drug and alcohol use, Sexuality and Suicide youth psychosocial assessment tool

AIMS AND OBJECTIVES

To identify the percentage of young people presenting to a primary healthcare service targeting homeless youth, in Melbourne, Australia, who, based on youth-specific Home, Education, Activities, Drug and alcohol use, Sexuality and Suicide (HEADSS) psychosocial assessment tool, were screened for the sexually transmitted infection Chlamydia and tested positive.

BACKGROUND

Homeless young people are at high risk of poor health outcomes including sexual health. Chlamydia prevalence is highest in 16-24 years. Youth psychosocial assessment tools such as the HEADSS can engage young people and provide comprehensive health assessment that identifies health risks.

DESIGN

A retrospective audit.

METHODS

One hundred consecutive client files of youth who presented to a primary healthcare service for the first time were selected. Client data were collected at the health services' inner city drop-in clinic and clinical refuge outreach (CRO). HEADSS assessments were made on new presentations to identify those at risk of Chlamydia. These young people were then offered screening for Chlamydia using a first-pass urine sample.

RESULTS

One hundred HEADSS assessments were audited, of which 15 were incomplete. Of the 85 completed HEADSS assessments, 43 were tested and 11 had Chlamydia-positive results.

CONCLUSION

Comprehensive youth assessment tools, such as the HEADSS, can provide a valuable resource in identifying sexual health risks such as Chlamydia. In turn, skilled nursing staff can provide opportunistic screening. Early identification and treatment for Chlamydia can reduce the spread and sequela of this highly infectious STI.

RELEVANCE TO CLINICAL PRACTICE

Youth health nurses can enhance their nursing practice in working with young people at risk of homelessness and improve their health outcomes by employing youth-specific assessments.

To develop and measure the effectiveness and acceptability of a pharmacy-based chlamydia screening intervention in Australia

OBJECTIVES

To develop and measure the effectiveness and acceptability of a pharmacy-based chlamydia screening intervention called Emergency Contraception Mediated Pharmacy Access to Chlamydia Testing (ECOMPACT).

DESIGN

Selective, opportunistic and cross-sectional study targeting asymptomatic women requesting emergency contraception (EC).

SETTING

20 community pharmacies in the Perth metropolitan region, Australia.

METHODS

ECOMAPCT was developed through literature review and stakeholder consensus. Pharmacists were trained to offer ECOMPACT after the EC consultation. Women with signs and symptoms of sexually transmitted infections (STI) were referred to a physician for a full sexual health check. Asymptomatic women were offered a free ECOMPACT testing kit. The women self-collected a low-vaginal swab and returned their pathological specimen to designated drop-off sites. A pathology service analysed the specimens and sent the results to a sexual health physician. The effectiveness of ECOMPACT was determined by the uptake of the intervention and how well the target population was reached. An effective screening rate was calculated. Qualitative analysis was undertaken to understand acceptability issues from the perspective of the consumer and the pharmacists.

RESULTS

Of the 769 EC consultations in a 6-month period, 569 (78%) women were given information on chlamydia screening. All 247 (41%) agreed to participate. 81 (33%) of these women were ineligible. They were either symptomatic (n=33; 41%), or were under 18 years of age (n=48; 59%). Pharmacists successfully requested 166 (67%) pathology tests, of which 46 (28%) were returned to a pathology drop-off site. All tested negative for Chlamydia trachomatis. The effective screening rate was 6%. Consumers and pharmacists considered ECOMPACT to be highly convenient and the time taken to offer a chlamydia test along with an EC consultation as highly appropriate.

CONCLUSIONS

ECOMPACT was found to be simple, effective and acceptable. Given the opportunity, adequate training and support, community pharmacists in Australia were capable of requesting direct-to-consumer chlamydia tests.

Chlamydia trachomatis recombinant MOMP encapsulated in PLGA nanoparticles triggers primarily T helper 1 cellular and antibody immune responses in mice: a desirable candidate nanovaccine

We recently demonstrated by in vitro experiments that PLGA (poly D, L-lactide-co-glycolide) potentiates T helper 1 (Th1) immune responses induced by a peptide derived from the recombinant major outer membrane protein (rMOMP) of Chlamydia trachomatis, and may be a promising vaccine delivery system. Herein we evaluated the immune-potentiating potential of PLGA by encapsulating the full-length rMOMP (PLGA-rMOMP), characterizing it in vitro, and investigating its immunogenicity in vivo. Our hypothesis was that PLGA-rMOMP triggers Th1 immune responses in mice, which are desirable prerequisites for a C. trachomatis candidate nanovaccine. Physical-structural characterizations of PLGA-rMOMP revealed its size (approximately 272 nm), zeta potential (−14.30 mV), apparent spherical smooth morphology, and continuous slow release pattern. PLGA potentiated the ability of encapsulated rMOMP to trigger production of cytokines and chemokines by mouse J774 macrophages. Flow cytometric analyses revealed that spleen cells from BALB/c mice immunized with PLGA-rMOMP had elevated numbers of CD4+ and CD8+ T cell subsets, and secreted more rMOMP-specific interferon-gamma (Th1) and interleukin (IL)-12p40 (Th1/Th17) than IL-4 and IL-10 (Th2) cytokines. PLGA-rMOMP-immunized mice produced higher serum immunoglobulin (Ig)G and IgG2a (Th1) than IgG1 (Th2) rMOMP-specific antibodies. Notably, sera from PLGA-rMOMP-immunized mice had a 64-fold higher Th1 than Th2 antibody titer, whereas mice immunized with rMOMP in Freund’s adjuvant had only a four-fold higher Th1 than Th2 antibody titer, suggesting primarily induction of a Th1 antibody response in PLGA-rMOMP-immunized mice. Our data underscore PLGA as an effective delivery system for a C. trachomatis vaccine. The capacity of PLGA-rMOMP to trigger primarily Th1 immune responses in mice promotes it as a highly desirable candidate nanovaccine against C. trachomatis.

A risk-benefit analysis of factor V Leiden testing to improve pregnancy outcomes: a case study of the capabilities of decision modeling in genomics

PURPOSE

We sought to assess the benefits, risks, and personal utility of factor V Leiden mutation testing to improve pregnancy outcomes and to assess the utility of decision-analytic modeling for complex outcomes in genomics.

METHODS

We developed a model to evaluate factor V Leiden testing among women with a history of recurrent pregnancy loss, including heparin therapy during pregnancy in mutation-positive women. Outcomes included venous thromboembolism, major bleeds, pregnancy loss, maternal mortality, and quality-adjusted life-years.

RESULTS

Factor V Leiden testing in a hypothetical cohort of 10,000 women led to 7 fewer venous thromboembolic events, 90 fewer pregnancy losses, and an increase of 17 major bleeding events. Small improvements in quality-adjusted life-years were largely attributable to reduced mortality but also to improvements in health-related quality of life. However, sensitivity analyses indicate large variance in results due to data uncertainty. Furthermore, the complexity of outcomes limited our ability to fully capture the repercussions of testing in the quality-adjusted life-year measure.

CONCLUSION

Factor V Leiden testing involves tradeoffs between clinical and personal utility, and additional effectiveness data are needed for heparin use to prevent pregnancy loss. Decision-analytic methods offer somewhat limited value in assessing these tradeoffs, suggesting that evaluation of complex outcomes will require novel approaches to appropriately capture patient-centered outcomes.Genet Med 2013:15(5):374-381.

Chlamydia trachomatis, a hidden epidemic: effects on female reproduction and options for treatment

The number of genital tract Chlamydia trachomatis infections is steadily increasing worldwide, with approximately 50-70% of infections asymptomatic. There is currently no uniform screening practice, current antibiotic treatment has failed to prevent the increased incidence, and there is no vaccine available. We examined studies on the epidemiology of C. trachomatis infections, the effects infections have on the female reproductive tract and subsequent reproductive health and what measures are being taken to reduce these problems. Undetected or multiple infections in women can lead to the development of severe reproductive sequelae, including pelvic inflammatory disease and tubal infertility. There are two possible paradigms of chlamydial pathogenesis, the cellular and immunological paradigms. While many vaccine candidates are being extensively tested in animal models, they are still years from clinical trials. With no vaccine available and antibiotic treatment unable to halt the increased incidence, infection rates will continue to increase and cause a significant burden on health care systems.

Conversant or clueless? Chlamydia-related knowledge and practice of general practitioners in Western Australia

Background

A survey of Western Australia's general practitioners' (GPs') knowledge and practices relating to genital chlamydia infection was conducted in mid-2005, prior to a multi-media campaign which encouraged 15–24 year olds to seek chlamydia testing through their general practitioner (GP). The survey aimed to raise GPs' awareness of chlamydia in preparation for the campaign and to establish a baseline measure of their chlamydia-related knowledge and practices.

Methods

All 2038 GPs registered on the Australian Medical Publishing Company's database as practising in Western Australia were sent a survey which covered clinical features of chlamydia, investigations, treatment and public health issues; 576 (29%) responded.

Results

Most GPs were aware of chlamydia being common in the 20–24 year old age group, but less than half were aware that it is common in 15–19 year olds. GPs missed many opportunities for chlamydia testing in patients likely to be at risk of STIs, largely because they thought the patient would be embarrassed. It is of concern that public health responsibilities in relation to chlamydia, ie notification and contact tracing, were not undertaken by all GPs.

Conclusion

Australia is currently piloting chlamydia screening. For this to be successful, GPs will need to maintain current knowledge and clinical suspicion about chlamydia, and be comfortable in asking and receiving information about sexual behaviours. Only then will GPs have a significant impact on curbing Australia's ever-increasing rates of chlamydia.