Analysis of laboratory testing results collected in an enhanced chlamydia surveillance system in Australia, 2008-2010

STI testing among young people attending music festivals in New South Wales, Australia: exploring the client segmentation concept in the 'Down to Test' program

Background The 'Down to Test (DTT)' campaign is a sexually transmissible infection (STI) social marketing intervention delivered through outdoor music festival activations and supported by digital media communications in New South Wales, Australia. This paper investigates whether and how the tailored messages reached the intended audience. Methods Data was collected through three annual rounds of online surveys post campaign exposure, targeting young people (aged 15-29years) attending 14 music festivals in NSW from October 2017 to March 2020. Descriptive statistics, principal component analysis and multivariable logic regression were applied to identify the key client segment and factors associated with a strong intention for future STI screening. Results Of the 10044 participants with a valid urine specimen submitted, 261 (2.8%) tested positive for chlamydia. Altogether, 1776 participants (median age=22) self-completed the evaluation surveys online with more being female (73.4%) than male (26.2%). Participants were mostly Australian-born (89.5%), heterosexual (82.6%) and the majority being sexually active (96.7%). Rates of self-reported lifetime STI testing (70.4%) and intention for future STI screening ('definitely yes' in the next 12months, 39.0%) were also high. The most significant factor associated with future intention for STI testing is the Sexual Experience and Perception Factor (adjusted odds ratio [AOR]=2.02; 95%CI 1.76-2.32; P<0.001), followed by the Sexual Beliefs and Attitudes Factor (AOR=1.14; 95% CI 1.01-1.30; P<0.05). Conclusions The NSW state-wide DTT campaign has largely reached sexually active youth who are attentive to sexual health promotion messages and contributed to enhanced STI screening in a fun and peer-supportive environment.

Chlamydia trachomatis and Mycoplasma genitalium prevalence and associated factors among women presenting to a pregnancy termination and contraception clinic, 2009-2019

BACKGROUND

Risk of pelvic inflammatory disease associated with Chlamydia trachomatis and Mycoplasma genitalium is increased after termination of pregnancy (TOP) and may be increased after insertion of intrauterine devices (IUDs). Screening prior to these procedures is recommended only for C. trachomatis. We examined C. trachomatis and M. genitalium prevalence and associated factors among women presenting to a pregnancy termination and contraception service over 10 years.

METHODS

Retrospective analysis of clinical data collected from 17 573 women aged 15-45 years in 2009-2019 and for 266 M. genitalium positive women tested for macrolide resistance-associated mutations in 2016-2019.

RESULTS

C. trachomatis and M. genitalium prevalence was 3.7% and 3.4%, respectively. In multivariable analyses, shared risk factors were younger age (p<0.001, for both C. trachomatis and M. genitalium), socioeconomic disadvantage (p=0.045 and p=0.008, respectively) and coinfection (p<0.001, for both sexually transmitted infections), with 10.1% of C. trachomatis positive women also positive for M. genitalium. Additional risk factors were earlier year of visit (p=0.001) for C. trachomatis and for M. genitalium residing outside a major city (p=0.013). The proportion of M. genitalium infections tested between 2016 and 2019 with macrolide resistance-associated mutations was 32.7%.

CONCLUSIONS

Given the high level of antimicrobial resistance and the prevalence of coinfection, testing C. trachomatis positive women for M. genitalium could be considered in this setting to prevent further spread of resistant infections. Further research is required into the causal link between M. genitalium and pelvic inflammatory disease in women undergoing TOP and IUD insertion.

Analysis of diagnostic data for sexually transmissible infections in South Australian Aboriginal Community Controlled Health Services (2008-16)

Australian Aboriginal communities experience a high burden of sexually transmissible infections (STIs). Since 2009, a comprehensive sexual health program has been implemented at nine Aboriginal Community Controlled Health Services in South Australia. This study assessed trends in STI testing and positivity using deidentified diagnostic data from this period (2008-16).

METHODS

Testing data for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) from one urban, three regional and five remote Aboriginal health services were analysed using logistic regression.

RESULTS

From 2008 to 2016, testing increased for CT (twofold), NG (threefold) and TV (sixfold). On average, 30% of testing occurred during an annual 6-week screen. Fewer males were tested (range 27-38% annually). Mean annual STI testing coverage was 28% for 16- to 30-year-old clients attending regional or remote services (2013-16). Positivity at first testing episode for all three infections declined during the study period. From 2013 to 2016, when testing was stable and changes in positivity were more likely to indicate changes in prevalence, there were significant reductions in CT positivity (adjusted odds ratio (aOR) 0.4; 95% confidence interval (CI) 0.2-0.5) and TV positivity (aOR 0.6, 95% CI 0.4-0.9), although declines were statistically significant for females only. There was no significant decrease in NG positivity (aOR 0.9; 95% CI 0.5-1.5).

CONCLUSIONS

Since the sexual health program began, STI testing increased and STI positivity declined, but significant reductions observed in CT and TV positivity were confined to females. These findings suggest evidence of benefit from sustained, comprehensive sexual health programs in Aboriginal communities with a high STI prevalence, but highlight the need to increase STI testing among men in these communities.

Monitoring human papillomavirus prevalence among young Australian women undergoing routine chlamydia screening

INTRODUCTION

Australia has recently implemented major changes in cervical cancer prevention policies including introduction of primary human papillomavirus (HPV) screening starting at age 25, and replacement of the quadrivalent HPV vaccine with the nonavalent vaccine in the national school-based program. We assessed the feasibility and utility of conducting HPV testing in residual clinical specimens submitted for routine Chlamydia trachomatis screening, as a means of tracking HPV vaccine program impact among young sexually active women.

METHODS

De-identified residual specimens from women aged 16-24 years submitted for chlamydia testing were collected from three pathology laboratories in Victoria and New South Wales. Limited demographic information, and chlamydia test results were also collected. Patient identifiers were sent directly from the laboratories to the National HPV Vaccination Program Register, to obtain HPV vaccination histories. Samples underwent HPV genotyping using Seegene Anyplex II HPV 28 assay.

RESULTS

Between April and July 2018, 362 residual samples were collected, the majority (60.2%) of which were cervical swabs. Demographic data and vaccination histories were received for 357 (98.6%) women (mean age 21.8, SD 2.0). Overall, 65.6% of women were fully vaccinated, 9.8% partially, and 24.7% unvaccinated. The majority (86.0%) resided in a major city, 35.9% were classified in the upper quintile of socioeconomic advantage and chlamydia positivity was 7.8%.The prevalence of quadrivalent vaccine-targeted types (HPV6/11/16/18) was 2.8% (1.5-5.1%) overall with no differences by vaccination status (p = 0.729). The prevalence of additional nonavalent vaccine-targeted types (HPV31/33/45/52/58) was 19.3% (15.6-23.8%). One or more oncogenic HPV types were detected in 46.8% (95% CI 41.6-52.0%) of women.

CONCLUSIONS

HPV testing of residual chlamydia specimens provides a simple, feasible method for monitoring circulating genotypes. Applied on a larger scale this method can be utilised to obtain a timely assessment of nonavalent vaccine impact among young women not yet eligible for cervical screening.

Pathology Laboratory Surveillance in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of Sexually Transmitted Infections and Blood-Borne Viruses: Protocol for a Cohort Study

Background

Passive surveillance is the principal method of sexually transmitted infection (STI) and blood-borne virus (BBV) surveillance in Australia whereby positive cases of select STIs and BBVs are notified to the state and territory health departments. A major limitation of passive surveillance is that it only collects information on positive cases and notifications are heavily dependent on testing patterns. Denominator testing data are important in the interpretation of notifications.

Objective

The aim of this study is to establish a national pathology laboratory surveillance system, part of a larger national sentinel surveillance system called ACCESS (the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance). ACCESS is designed to utilize denominator testing data to understand trends in case reporting and monitor the uptake and outcomes of testing for STIs and BBVs.

Methods

ACCESS involves a range of clinical sites and pathology laboratories, each with a separate method of recruitment, data extraction, and data processing. This paper includes pathology laboratory sites only. First established in 2007 for chlamydia only, ACCESS expanded in 2012 to capture all diagnostic and clinical monitoring tests for STIs and BBVs, initially from pathology laboratories in New South Wales and Victoria, Australia, to at least one public and one private pathology laboratory in all Australian states and territories in 2016. The pathology laboratory sentinel surveillance system incorporates a longitudinal cohort design whereby all diagnostic and clinical monitoring tests for STIs and BBVs are collated from participating pathology laboratories in a line-listed format. An anonymous, unique identifier will be created to link patient data within and between participating pathology laboratory databases and to clinical services databases. Using electronically extracted, line-listed data, several indicators for each STI and BBV can be calculated, including the number of tests, unique number of individuals tested and retested, test yield, positivity, and incidence.

Results

To date, over 20 million STI and BBV laboratory test records have been extracted for analysis for surveillance monitoring nationally. Recruitment of laboratories is ongoing to ensure appropriate coverage for each state and territory; reporting of indicators will occur in 2019 with publication to follow.

Conclusions

The ACCESS pathology laboratory sentinel surveillance network is a unique surveillance system that collects data on diagnostic testing, management, and care for and of STIs and BBVs. It complements the ACCESS clinical network and enhances Australia’s capacity to respond to STIs and BBVs.

International Registered Report Identifier (IRRID)

DERR1-10.2196/13625

Testing for chlamydial infection: are we meeting clinical guidelines? Evidence from a state-level laboratory data linkage analysis for 15- to 29-year-olds

Background Clinical guidelines recommend annual chlamydia tests for all sexually active people aged 15-29 years. This study measured adherence to these guidelines and compared testing rates to the projected levels required to reduce chlamydia prevalence.

METHODS

All chlamydia tests conducted in Tasmania during 2012-13, for residents aged 15-29 years, were linked. Data linkage allowed individuals who had multiple tests across different healthcare settings to be counted only once each year in analyses. Rates of testing and test positivity by age, sex, rebate status and socioeconomic indicators were measured.

RESULTS

There were 31899 eligible tests conducted in 24830 individuals. Testing coverage was higher in females (21%, 19404/92685) than males (6%, 5426/98123). Positivity was higher in males (16%, 862/5426) than females (10%, 1854/19404). Most tests (81%, 25803/31899) were eligible for a rebate. Positivity was higher in females with non-rebatable tests (12%, 388/3116 compared with those eligible for a rebate (9%, 1466/16285). More testing occurred in areas of middle disadvantage (10%, 9688/93678) compared with least (8%, 1680/21670) and most (10%, 7284/75460) (both P<0.001) disadvantaged areas. Higher test positivity was found in areas of most-disadvantage (11%, 822/7284) compared with middle- (10%, 983/9688) and least- (8%, 139/1680) disadvantaged areas.

CONCLUSIONS

Chlamydia testing rates are lower than recommended levels. Sustaining the current testing rates in females aged 20-24 years may reduce population prevalence within 10 years. This study meets key priorities of national strategies for chlamydia control by providing a method of monitoring testing coverage and evidence to evaluate prevention programs.

The importance of accounting for testing and positivity in surveillance by time and place: an illustration from HIV surveillance in Japan

The number of tests performed is an important surveillance indicator. We illustrate this point using HIV surveillance data, focusing on Tokyo and Okinawa, two prefectures with high HIV notification rates in Japan. Restricting to data reported from local public health centres and affiliate centres where testing data are accessible, we assessed HIV surveillance data during 2007-2014, based on the annual HIV notification rate (per 100 000 population), HIV testing rate (per 100 000 population) and proportion testing HIV-positive (positivity). Nationally, testing activity and positivity showed an inverse relationship; in 2008, the testing rate peaked, but positivity was lowest. While notification rates were higher for Tokyo (median = 0.98, range = 0.89-1.33) than Okinawa (median = 0.61, range = 0.42-1.09), Okinawa had slightly higher testing rates (median = 187, range = 158-274) relative to Tokyo (median = 172, range = 163-210). Positivity was substantially lower in Okinawa (median = 0.34%, range = 0.24-0.45%) compared with Tokyo (median = 0.57%, range = 0.46-0.67%). Relative to the national testing rate (median = 85, range = 80-115) and positivity (median = 0.34%, range = 0.28-0.36%), Tokyo had higher positivity, despite more testing. In 2014 in Okinawa, all three indicators increased, providing a strong reason to be concerned as positivity increased despite more testing. Together with other information, accounting for testing and positivity improve interpretation of surveillance data to guide public health assessments.

High rates of chlamydia found among 12- to 16-year-olds attending a rural sexual health clinic: implications for practice

Background Chlamydia is the most commonly diagnosed bacterial sexually transmissible infection (STI) and is asymptomatic in ~80% of women. If untreated, potential consequences include pelvic inflammatory disease, ectopic pregnancy and infertility.

METHODS

In 2014, a retrospective audit was undertaken at a rural service to determine what proportion of patients were aged 12-16 years, infected with chlamydia and their reasons for attending the clinic.

RESULTS

There were 111 patients aged 12-16 years attending during 2011-2014; 104 (95%) were female. One hundred and ninety-four chlamydia tests were conducted, with the proportion of patients having at least one test annually being 100% in 2011, 81% in 2012, 72% in 2013 and 78% in 2014. There was no difference in the proportion tested by age during the study (P=0.59). Forty-six tests were positive for chlamydia (23.7%; 95%CI: 17.8%, 30.9%) with proportions decreasing with increasing age from 46.7% (95%CI: 16.4%, 79.5%) in 12- or 13-year-olds to 15.5% (95%CI: 9.4%, 24.2%) in 16-year-olds (P=0.02). The reasons for attending when a chlamydia test was ordered included: (i) fear of pregnancy (18.3%, 34/185); (ii) symptoms (16.7%, 31/185); (iii) STI test/treatment (32.4%, 60/185); and (iv) contraception (32.4%, 60/185). Only 29.7% (33/111) would have been tested if symptoms or requesting a test were impetus.

CONCLUSION

Sexually active 12- to 16-year-olds should be tested for chlamydia, and establishing their sexual history is crucial. Amending the current Australian guidelines to annual testing of any sexually active person under the age of 30 years should be considered.

Correlates of sexually transmissible infection testing among a sample of at-risk young Australians

Annual chlamydia testing is recommended for all sexually active Australians aged 15-29 years; however, the testing rate is below recommended levels. Three surveys at a Melbourne music festival were conducted over 2012-14 to identify correlates of sexually transmissible infection (STI) testing among young people at risk of STIs. In total, 3588 participants were recruited; 72% reported having sex in the past year. Based on sexual behaviours, 38% of sexually active participants were classified as at risk of contracting STIs. In the past year, at-risk participants had significantly higher odds of reporting a STI test (37%) than participants classified as not at risk (24%) (OR=1.9; CI=1.6-2.3). Among at-risk participants, correlates of STI testing in the past year included being aged 20-24 years, visiting a GP, higher knowledge levels, earlier sexual debut and reporting more than five lifetime partners. Testing rates in our sample did not meet levels required to reduce chlamydia prevalence. However, the testing rate was higher in at-risk participants than participants who were not at risk. Future programs aiming to increase chlamydia testing should improve knowledge and promote the importance of testing after risk exposure, particularly among 16- to 19-year-olds.

Anorectal swabs as a marker of male-to-male sexual exposure in STI surveillance systems

Identification of priority populations such as men who have sex with men (MSM) is important in surveillance systems to monitor trends of sexually transmitted infections (STIs). We explored using routinely collected non-behavioural data as a means to establish MSM status in surveillance by assessing anorectal swab as a marker of male-to-male sexual exposure. We used chlamydia testing data from a sexual health clinic, 2007-2012. Men reporting any male sexual partner(s) in the previous 12 months were considered MSM. The dataset was split into development and validation samples to develop a univariate predictive model and assess the model fit. The dataset included 30 358 individual men and 48 554 episodes of STI testing; 45% were among reported MSM and an anorectal swab was performed in 40% of testing episodes. Anorectal swabbing had good diagnostic performance as a marker for MSM status (sensitivity = 87%, specificity = 99%, positive predictive value = 98·6%, negative predictive value = 90·3%). The model showed good fit against the internal validation sample (area under the curve = 0·93). Anorectal swabs are a valid marker of MSM behaviour in surveillance data from sexual health clinics, and they are likely to be particularly useful for monitoring STI trends among MSM with higher risk behaviour.

Chlamydia trachomatis neither exerts deleterious effects on spermatozoa nor impairs male fertility

Chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection. However, whether Chlamydia trachomatis has a negative impact on sperm quality and male fertility is still controversial. Herein, we report the effects on sperm quality of the in vitro exposure of spermatozoa to Chlamydia trachomatis, and also the effects of male genital infection on male fertility using an animal model. Human and mouse sperm were obtained from healthy donors and cauda epididimys from C57BL/6 mice, respectively. Highly motile human or mouse spermatozoa were in vitro exposed to C. trachomatis (serovar E or LGV) or C. muridarum, respectively. Then, sperm quality parameters were analyzed. Moreover, male fertility of Chlamydia muridarum infected male C57BL/6 mice was assessed. Human or murine sperm in vitro exposed to increasing bacterial concentrations or soluble factors from C. trachomatis or C. muridarum, respectively, did not show differences in sperm motility and viability, apoptosis, mitochondrial membrane potential, DNA fragmentation, ROS production and lipid peroxidation levels, when compared with control sperm (p > 0.05). Moreover, no differences in fertility parameters (potency, fecundity, fertility index, pre- and post-implantation loss) were observed between control and infected males. In conclusion, our results indicate that Chlamydia spp. neither directly exerts deleterious effects on spermatozoa nor impairs male fertility.

Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature

In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM), and men who have sex only with women (MSW), including distribution by anatomical site. Among women, prevalence was found to be 0.6–35.8% for rectal gonorrhea (median reported prevalence 1.9%), 0–29.6% for pharyngeal gonorrhea (median 2.1%), 2.0–77.3% for rectal chlamydia (median 8.7%), and 0.2–3.2% for pharyngeal chlamydia (median 1.7%). Among MSM, prevalence was found to be 0.2–24.0% for rectal gonorrhea (median 5.9%), 0.5–16.5% for pharyngeal gonorrhea (median 4.6%), 2.1–23.0% for rectal chlamydia (median 8.9%), and 0–3.6% for pharyngeal chlamydia (median 1.7%). Among MSW, the prevalence was found to be 0–5.7% for rectal gonorrhea (median 3.4%), 0.4–15.5% for pharyngeal gonorrhea (median 2.2%), 0–11.8% for rectal chlamydia (median 7.7%), and 0–22.0% for pharyngeal chlamydia (median 1.6%). Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.

Chlamydia trachomatis infection prevalence and serovar distribution in a high-density urban area in the north of Italy

The aim of this study was to assess Chlamydia trachomatis (CT) infection prevalence and serovar distribution in a high-density urban area in the north of Italy, by comparing different groups of subjects divided on the basis of the type of care provider they referred to (STI Clinic, gynaecologists or general practitioners). From January 2011 to May 2014, all the specimens submitted to the Microbiology Laboratory of St Orsola Hospital in Bologna for CT detection were tested by PCR assay. For positive specimens, molecular genotyping based on RFLP analysis was performed. Total prevalence of CT infection was 8.1 %, with significant differences between subgroups (P<0.01) but stable during the study period. The STI Clinic was mainly responsible for CT diagnosis, whereas the lowest infection prevalence was detected in gynaecological clinics, despite the high number of tests performed. Extra-genital samples were almost exclusively collected from males at the STI Clinic. Interestingly, 13.3 % of patients providing extra-genital specimens were positive for CT on rectal and/or pharyngeal swabs, and 4.4 % of cases would have been missed if extra-genital sites had not been tested. The most common serovar was E, and serovar distribution was influenced by gender (P<0.01), age (P<0.01), care provider (P=0.01) and anatomical site (P<0.01). The L2 serovar was detected only in extra-genital samples from males at the STI Clinic. Knowledge about care providers' contributions in CT testing and diagnosis is essential for infection control. CT typing is crucial for appropriate management of specific infections, such as lymphogranuloma venereum in extra-genital samples of high-risk populations.

What is needed to guide testing for anorectal and pharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae in women and men? Evidence and opinion

Background

Anorectal and pharyngeal infections with Chlamydia trachomatis (CT) and Neisseria gonorrheae (NG) are commonly observed in men who have sex with men (MSM). There is increasing evidence that such infections at extra-genital sites are also common in women. In both sexes, these infections are largely overlooked as they are not routinely tested for in regular care. Testing based on sexual behavior or symptoms would only detect half of these extra-genital infections. This paper elucidates the differences and similarities between women and MSM, regarding the epidemiology of extra-genital CT and NG. It discusses the clinical and public health impact of untested extra-genital infections, how this may impact management strategies, and thereby identifies key research areas.

Discussion

Extra-genital CT is as common in women as it is in MSM; NG in women is as common at their extra-genital sites as it is at their genital sites. The substantial numbers of extra-genital CT and NG being missed in women and MSM indicate a need to test and treat more patients and perhaps different choices in treatment and partner management strategies. Doing so will likely contribute to reduced morbidity and transmission in both sexes. However, in our opinion, it is clear that there are several knowledge gaps in understanding the clinical and public health impact of extra-genital CT and NG. Key research areas that need to be addressed concern associated morbidity (anorectal and reproductive morbidity due to extra-genital infections), ‘the best’ management strategies, including testing and treatment for extra-genital CT, extra-genital treatment resistance, transmission probabilities between partners and between anatomic sites in a woman, and impact on transmission of other infections. Data are also lacking on cost-effectiveness of pharyngeal testing, and of NG testing and anorectal CT testing in women. Gaps in the management of extra-genital CT and NG may also apply for other STIs, such Mycoplasma genitalium.

Summary

Current management strategies, including testing, to address extra-genital CT and NG in both sexes are suboptimal. Comparative data on several identified key themes in women and MSM are lacking and urgently needed to guide better management of extra-genital infections.

Who tests whom? A comprehensive overview of Chlamydia trachomatis test practices in a Dutch region among different STI care providers for urogenital, anorectal and oropharyngeal sites in young people: a cross-sectional study

OBJECTIVES

To evaluate and compare Chlamydia trachomatis (CT) diagnostic test practices of different sexually transmitted infection (STI) care providers in 16-29 year olds from one defined geographic Dutch region (280,000 inhabitants). Both number and proportion of positive CT tests (ie, test positivity) were assessed, and factors associated with these outcomes.

METHODS

Data on laboratory testing and diagnosis of urogenital, anorectal and oropharyngeal CT between 2006 and 2010 were retrieved from general practitioners (GPs), gynaecologists, an STI clinic and a population-based chlamydia screening programme. Multivariable regression analyses explored associations between age, sex, test year, socio-economic status (SES) and STI care provider and the outcomes being the number of tests and test positivity.

RESULTS

Overall, 22,831 tests were performed (1868 positive; 8.2%). Extragenital (ie, anorectal and oropharyngeal) tests accounted for 4% of all tests (7.5% positive) and were almost exclusively (99%) performed by the STI clinic. STI clinics tested most men (37.2% of all tested men), whereas GPs tested most women (29.9% of all tested women). GPs and STI clinics accounted for 73.3% (1326/1808) of urogenital CT diagnoses. In women, the number of tests increased with age, whereas test positivity decreased for all STI care providers. Lower SES was associated with higher test positivity in GP and gynaecology patients.

CONCLUSIONS

STI clinics performed most CT tests in men, whereas GPs performed most CT tests in women. GPs and STI clinics accounted for the majority of positives. Extragenital CT testing is rarely performed outside the STI clinic and needs to be promoted, especially in men who have sex with men.

Increased testing for Neisseria gonorrhoeae with duplex nucleic acid amplification tests in Australia: implications for surveillance

Background Gonorrhoea notifications have been increasing in Australia’s cities, in both men and women. We investigated if this could be, at least in part, a result of a testing artefact. Methods: We surveyed 28 laboratories that were known to test for both Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) to determine their testing and reporting practices, and when these practices were instituted. Results: By 2012, 23 (82%) of the laboratories were routinely performing duplex nucleic acid amplification tests for both CT and NG even if a test for only one organism was requested, up from 9 (32%) laboratories before 2007. Although written reports of negative NG tests were not provided if the test was not requested, positive NG tests were always communicated to the attending clinician. Conclusions: The move towards routine duplex testing for CT and NG has probably resulted in more Australians being tested for NG than ever before. While this change has advantages for case-finding and improved public health outcomes, it also brings an increasing potential for false-positive NG tests. Recent trends in NG notifications should be interpreted with caution.

Young Risk Takers: Alcohol, Illicit Drugs, and Sexual Practices among a Sample of Music Festival Attendees

Background. Alcohol and other drug use and sexual risk behaviour are increasing among young Australians, with associated preventable health outcomes such as sexually transmissible infections (STIs) on the rise. Methods. A cross-sectional study of young people's health behaviours conducted at a music festival in Melbourne, Australia, in 2011. Results. 1365 young people aged 16–29 completed the survey; 62% were female with a mean age of 20 years. The majority (94%, n = 1287) reported drinking alcohol during the previous 12 months; among those, 32% reported “binge” drinking (6+ drinks) at least weekly. Half (52%) reported ever using illicit drugs and 25% reported past month use. One-quarter (27%) were identified as being at risk of STIs through unprotected sex with new or casual partners during the previous 12 months. Multivariable analyses found that risky sexual behaviour was associated with younger age (≤19 years), younger age of sexual debut (≤15 years), having discussed sexual health/contraception with a doctor, regular binge drinking, and recent illicit drug use. Conclusion. Substance use correlated strongly with risky sexual behaviour. Further research should explore young people's knowledge of alcohol/drug-related impairment and associated risk-taking behaviours, and campaigns should encourage appropriate STI testing among music festival attendees.

Chlamydia muridarum infection-induced destruction of male germ cells and sertoli cells is partially prevented by Chlamydia major outer membrane protein-specific immune CD4 cells

Chlamydia trachomatis infections are increasingly prevalent worldwide. Male chlamydial infections are associated with urethritis, epididymitis, and orchitis; however, the role of Chlamydia in prostatitis and male factor infertility remains controversial. Using a model of Chlamydia muridarum infection in male C57BL/6 mice, we investigated the effects of chlamydial infection on spermatogenesis and determined the potential of immune T cells to prevent infection-induced outcomes. Antigen-specific CD4 T cells significantly reduced the infectious burden in the penile urethra, epididymis, and vas deferens. Infection disrupted seminiferous tubules, causing loss of germ cells at 4 and 8 wk after infection, with the most severely affected tubules containing only Sertoli cells. Increased mitotic proliferation, DNA repair, and apoptosis in spermatogonial cells and damaged germ cells were evident in atrophic tubules. Activated caspase 3 (casp3) staining revealed increased (6-fold) numbers of Sertoli cells with abnormal morphology that were casp3 positive in tubules of infected mice, indicating increased levels of apoptosis. Sperm count and motility were both decreased in infected mice, and there was a significant decrease in morphologically normal spermatozoa. Assessment of the spermatogonial stem cell population revealed a decrease in promyelocytic leukemia zinc finger (PLZF)-positive cells in the seminiferous tubules. Interestingly, adoptive transfer of antigen-specific CD4 cells, particularly T-helper 2-like cells, prior to infection prevented these effects in spermatogenesis and Sertoli cells. These data suggest that chlamydial infection adversely affects spermatogenesis and male fertility, and that vaccination can potentially prevent the spread of infection and these adverse outcomes.