BACKGROUND:Australia is reporting increasing notifications of sexually transmitted infections (STIs). Effective control depends on timely and equitable testing. However, evidence of testing and diagnosis patterns across diverse populations is limited. This study aimed to describe STI testing and diagnosis by different demographics in Victoria. METHODS:A 12-month online survey in Victoria, Australia recruited individuals aged 16 years and older through the Melbourne Sexual Health Centre, the Centre for Excellence in Rural Sexual Health, targeted social media advertisements, and community digital outreach. Data was collected on self-reported STI testing (blood, swab, urine, or no test) and STI diagnosis in the past 12 months. Subgroup analyses examined differences by age, residential location, and population groups. Chi-squared tests were used to compare the proportions of STI testing and diagnosis across different subgroups. RESULTS:We included 2327 participants in this analysis. Overall, 50.2% of participants reported blood testing, 39.8% swab testing, 47.3% urine testing, and 41.0% did not have any HIV/STI test in the past 12 months. In total, 17.3% reported an STI diagnosis. Participants in regional Victoria were more likely not to test (54.0%) compared with those in greater Melbourne (40.0%). The proportion with no testing was lowest among gay and bisexual cis-men (10.5%) and highest among heterosexual cis-men (57.1%). The proportion with no testing declined significantly with age from 72.7% among those aged 16-19 years to 52.4% at 20-24 years. CONCLUSION:Inequities in STI testing and diagnosis persist across age, population groups, and geography. Further research is needed to identify structural and behavioural barriers and to guide strategies that ensure equitable access to timely STI care.

BACKGROUND:No vaccines are currently licensed for the prevention of Neisseria gonorrhoeae infection. Observational studies suggest that the four-component meningococcal serogroup B vaccine (4CMenB) may reduce the risk of gonorrhea. METHODS:In this multicenter, double-blind, randomized, placebo-controlled trial, we assigned, in a 1:1 ratio, men who have sex with men (MSM) to receive two doses of 4CMenB or placebo. All the participants had recently received a diagnosis of N. gonorrhoeae infection or infectious syphilis and either tested negative for human immunodeficiency virus (HIV) and were receiving HIV preexposure prophylaxis or were living with HIV. Screening for sexually transmitted infections, including N. gonorrhoeae nucleic acid amplification testing of samples obtained from urogenital, anorectal, and oropharyngeal sites, was performed quarterly for 2 years. The primary outcome was a first N. gonorrhoeae infection after the receipt of vaccine or placebo in the per-protocol population (participants who received both 4CMenB or placebo doses, attended at least two scheduled follow-up visits after the second dose, and did not meet any exclusion criterion pertinent to the assessment of efficacy). RESULTS:From July 2021 through May 2023, a total of 654 participants underwent randomization, of whom 587 were included in the primary analysis. The incidence of N. gonorrhoeae infection was 48.1 events per 100 person-years (160 events among 296 participants) in the 4CMenB group and 47.8 events per 100 person-years (155 events among 291 participants) in the placebo group (incidence rate ratio, 1.01; 95% confidence interval [CI], 0.80 to 1.26; P = 0.97), for a vaccine efficacy of -0.5% (95% CI, -26.2 to 19.9). Vaccine efficacy was 5.5% (95% CI, -56.0 to 42.8) for symptomatic infection, -6.4% (95% CI, -47.5 to 23.2) for asymptomatic infection, and -20.0% (95% CI, -90.2 to 23.9), -1.2% (95% CI, -33.0 to 23.0), and 2.6% (95% CI, -27.7 to 25.7) for urogenital, anorectal, and oropharyngeal infection, respectively. Serious adverse events occurred in 4.7% of the participants in the 4CMenB group and in 2.8% of those in the placebo group. CONCLUSIONS:4CMenB did not result in a lower incidence of N. gonorrhoeae infection than placebo among MSM who were at high risk for gonorrhea. (Funded by the Australian National Health and Medical Research Council and GSK; GoGoVax ClinicalTrials.gov number, NCT04415424.).

BACKGROUND:Digital self-reporting tools are increasingly used in sexual health clinics for individuals to disclose sensitive information. In December 2023, the Melbourne Sexual Health Centre replaced its touchscreen kiosk system with a smartphone-enabled Digital Front Door platform for administering computer-assisted self-interviewing (CASI) to collect sexual history data before clinical consultation. This study aimed to evaluate how this change impacted response completeness. METHODS:We conducted a before-and-after study using routine data collected from clients aged ≥16 years who attended Melbourne Sexual Health Centre from January to June 2023 (kiosks period) and from January to June 2024 (smartphone period). We compared the CASI completeness (i.e. the proportion of questions for which each client provided a response, based on the total number they were expected to complete) between the two periods. Linear regression with generalised estimating equations was used to examine associations between completeness and individuals' characteristics. RESULTS:Among 56,095 eligible consultations (28,093 kiosks; 28,002 smartphones), the mean questionnaire completeness was significantly lower in the smartphone group (36.2%) compared with the kiosk group (54.0%; P < 0.0001). The proportion of clients who did not respond to any single question (i.e. 0% completeness) increased from 45.1% (12,676/28,093) during the kiosk period to 57.4% (16,065/28,002) during the smartphone period. Smartphone use was associated with a 15.31 percentage point reduction in completeness (β = -15.31, 95% CI: -16.12 to -14.49) after adjusting for other confounding factors. Reduced completeness was also independently associated with older age, birth outside Oceania, Indigenous identity and people living with HIV. First-time attendees demonstrated substantially higher completeness. CONCLUSION:The transition from kiosks to smartphones for administering CASI was associated with a modest, but consistent, decline in data completeness. Incomplete CASI data may reduce clinic efficiency by requiring clinicians to collect missing information during consultations, posing challenges in high-demand settings. Further research is needed to assess whether response completeness improves as users become more familiar with the new digital system.

BACKGROUND:Syphilis infections are rising in many countries. Syphilis reinfections can occur among patients with ongoing risk. We aimed to describe the characteristics of syphilis reinfections and the interval time between syphilis reinfections. METHODS:This was a retrospective study of patients with two or more syphilis infections between 2011 and 2022 diagnosed at Melbourne Sexual Health Centre, Australia. RESULTS:474 patients, 98% men who have sex with men (MSM), had 1327 syphilis infections over 2062 person-years; 26.9% (n=357) primary syphilis, 20.9% (n=278) secondary and 48.3% (n=641) early latent syphilis. Individuals experienced up to nine syphilis infections. The proportion of people living with HIV (PLWH) increased with each subsequent syphilis infection from 40.1% (190/474) of first infections to 78.4% (29/37) of fifth infections. For first infections, the proportions were 36.5% for early latent, 31.6% for primary and 22.2% for secondary syphilis. In contrast, for fifth infections, proportions increased to 78.4% for early latent and decreased to 16.2% for primary and 5.4% for secondary syphilis. The median interinfection interval, between the first and second syphilis infection, for the entire cohort, was 656 days (IQR 325-1262 days). Pre-exposure prophylaxis (PrEP) users had a shorter median interinfection interval of 341 days (IQR 206-762 days), compared with the entire cohort (p<0.0001), HIV-negative patients not using PrEP (p<0.0001) and PLWH (p<0.0001). CONCLUSION:Among MSM, syphilis reinfections were common, especially among PLWH and HIV-negative PrEP users, with the latter having the shortest interval between infections. These groups should be retested for syphilis with frequent serological screening, Treponema pallidum PCR testing of syphilis lesions and should be targeted for syphilis prevention.

BACKGROUND:Gay and bisexual men who have sex with men (GBMSM) and trans and gender diverse people (TGD) are disproportionately affected by several vaccine-preventable diseases. However, research on vaccine uptake for both sexually transmitted and non-sexually transmitted infections among GBMSM and TGD remains limited. Understanding differences in uptake between selective (e.g. hepatitis A; meningococcal; human papillomavirus; HPV; mpox) and universal (e.g. influenza, COVID-19) is important for informing future immunisation policy and strategies. METHODS:We surveyed past vaccine uptake among GBMSM and TGD people living in Australia in July-November 2024. Participants were asked to self-report their vaccination status for the following six vaccines: COVID-19, influenza, hepatitis A, hepatitis B, HPV, meningococcal disease, and mpox. Vaccine uptake was calculated for each vaccine and stratified by age group, HIV status and PrEP use, gender, education, Medicare status, world region of birth, and jurisdiction of residence. RESULTS:The median age of the 2095 participants was 39 years (IQR: 31-50). The majority of the participants identified as cisgender men (94.7%). Overall, the COVID-19 vaccine had the highest uptake (97.5%), followed by hepatitis A/B (80.6%), influenza (72.8%), mpox (64.0%), HPV (35.9%), and meningococcal disease (30.3%). HIV-negative participants not using pre-exposure prophylaxis (PrEP) had lower vaccine uptake compared with HIV-negative PrEP users and people living with HIV. Higher education and having a Medicare card were associated with an overall increased vaccine uptake. CONCLUSION:Factors that increase vaccine uptake included being PLHIV and using PrEP, increased education, and having a Medicare card. Public health policies should consider targeted outreach, integration of vaccination into routine care and innovative health communication strategies.

BACKGROUND:Primary anorectal syphilis may go unnoticed in men who have sex with men (MSM) engaging in receptive anal sex. This study examined whether weekly digital anorectal examination (DARE) could help men self-detect abnormalities indicative of primary anorectal syphilis. METHODS:A cohort study of MSM aged ≥18 years who engage in receptive anal sex was conducted at the Melbourne Sexual Health Centre from 9 March 2022 to 4 August 2023. Participants received instructions on how to perform DARE, along with weekly text reminders for 48 weeks. Those who self-detected abnormalities were advised to seek clinical consultation. The primary outcome was the proportion of syphilis cases detected via DARE. Secondary outcomes included reports of DARE-related abnormalities, adherence, and experiences. RESULTS:Of the 222 men recruited, six men (2.7%; 95% CI: 1.0-5.8) were diagnosed with syphilis-1 primary anorectal infection detected by DARE, 2 secondary infections, and 3 early latent syphilis infections. There were 32 clinical consultations prompted by DARE. On average, men performed 78.2% (95% CI: 77.3-79.0) of their weekly DARE which showed no significant variation over time (Ptrend = 0.26). Most found DARE easy to perform (>95.0%) and would continue performing it if recommended for early syphilis detection (77.6%). CONCLUSIONS:Men's high adherence to performing we DARE suggests that it may complement routine screening for primary anorectal syphilis. However, its sensitivity may be limited, as 5 of 6 early syphilis cases did not have primary lesions that were self-detected by the 5 men.

BackgroundHIV self-testing (HIVST) can help overcome barriers to clinic-based testing among men who have sex with men (MSM). Peer-led distribution through existing social networks may further extend reach and acceptability.ObjectiveGuided by the Consolidated Framework for Implementation Research (CFIR), this study evaluated a social network-based HIVST intervention in Australia, in which “test promoters” distributed HIVST kits to friends and sexual partners, to identify facilitators and barriers to implementation.MethodsOnline semi-structured interviews were conducted with 22 MSM, including both test promoters and recipients involved in social network-based HIVST distribution trial. Interviews explored perceptions of acceptability, feasibility, and contextual appropriateness. Data were thematically analysed using the CFIR framework to identify multilevel implementation determinants.ResultsParticipants’ mean age was 33.3 years (SD = 8.2). Three interconnected enablers shaped successful implementation: (1) HIVST as an empowering, low-barrier testing option, enhancing privacy, convenience, and autonomy while mitigating stigma; (2) trust and peer credibility, which normalised test sharing and created culturally resonant pathways; and (3) collective responsibility for health, which sustained engagement and diffusion within MSM networks. HIVST’s privacy, convenience, and autonomy enhanced motivation, while peer reassurance reduced procedural anxiety, particularly around finger-prick sampling among first-time or infrequent testers. However, participants also identified persistent barriers, including culturally rooted discomfort discussing HIV, fear of judgment, and the risk of excluding socially isolated or newly arrived individuals. Social network distribution reframed testing as an act of care and solidarity, mitigating stigma and fostering collective ownership. Participants recommended culturally tailored materials, non-invasive test options, and expanded digital platforms to strengthen inclusion and reach.ConclusionSocial network-based HIVST represents a feasible, acceptable, and culturally responsive strategy to expand testing among MSM in high-income settings. By leveraging relational trust and community solidarity rather than financial incentives, this model offers a scalable and equitable pathway to advance progress toward national and global HIV prevention targets.

Background: Overseas-born gay, bisexual and other men who have sex with men (GBMSM) in Australia have higher HIV incidence and face barriers to accessing pre‑exposure prophylaxis (PrEP). Behavioural economics-informed “nudges” can support health decision‑making by gently shaping choices without restricting options. This study evaluated whether a community co‑designed, nudge‑based social media advertisement increased engagement with PrEP information compared with a standard information‑based advertisement. Methods: We conducted a two‑week quasi‑experimental social media campaign in March 2024. Jurisdictions and platforms alternated weekly between intervention and control ads using a crossover allocation to minimise bias. Engagement was defined as clicking through to the PAN (PrEPaccessNow, https://www.pan.org.au/) website. Secondary outcomes came from a post‑campaign survey assessing ad recall and subsequent PrEP‑related actions. Descriptive statistics, chi‑square tests, and two‑proportion z‑tests compared differences between arms. Findings: The intervention ad produced 5·0% click‑through rate, (755,935 impressions), outperforming the control ad’s (4·3% click‑through rate; absolute difference 0·7 percentage points; p < 0·0001), a 16·3% relative increase. Among PAN landing‑page participants (n=649 intervention; n=652 control), 45% were overseas‑born in both arms, with no significant engagement differences (p = 0·603). Newly arrived Asia‑born participants showed higher engagement with the intervention which approached statistical significance (47·1% vs. 37·1%; p = 0·076). Of 265 post‑campaign survey respondents, 93 recalled an ad and reported actions such as visiting the PAN website, conducting online PrEP searches, or having PrEP discussions, but there were no statistically significant differences between exposure groups. Two participants reported PrEP purchase, both from the control ad exposure group. Interpretation: The nudge‑based advertisement increased initial engagement but did not influence deeper PrEP‑related behaviours. It may help capture attention among newly arrived Asia‑born GBMSM, but additional strategies are needed to support progression from awareness to PrEP accessing behaviours.

Anorectal bacterial sexually transmitted infections, predominantly chlamydia, gonorrhoea and syphilis, represent a substantial and evolving global health challenge, with incidence rising despite widespread testing availability. In this Review, we examine the epidemiology and burden of anorectal sexually transmitted infections, explore the pathogenic mechanisms underlying infection and discuss advances in diagnosis, screening and prevention strategies. Anorectal infections are frequently asymptomatic, particularly among men who have sex with men, in which they often exceed the prevalence of urogenital infections. Asymptomatic persistence results from bacterial adaptation to rectal tissues and attenuated local immune responses that fall below symptom thresholds. Molecular diagnostics have transformed detection capabilities, yet substantial challenges persist in distinguishing viable from non-viable microorganisms, expanding point-of-care testing access and balancing screening benefits against antimicrobial stewardship concerns. Treatment approaches continue to evolve in response to emerging resistance patterns, particularly for gonorrhoea. Promising prevention innovations include doxycycline post-exposure prophylaxis, which substantially reduces chlamydia and syphilis incidence and artificial intelligence applications. However, practical implementation in diverse clinical settings remains limited. We highlight important gaps in knowledge and propose research priorities to advance effective control strategies.

OBJECTIVES:Many countries recommend 3-monthly chlamydia/gonorrhoea screening for gay, bisexual and other men who have sex with men (GBMSM). Evidence about the limited impact of frequent, asymptomatic gonorrhoea/chlamydia screening on population prevalence, coupled with concerns about overburdened health services and antimicrobial resistance (from frequent treatment), calls into question current approaches to asymptomatic screening. We explored sexual health professionals/experts' arguments in favour/against reducing asymptomatic screening using Polis (www.Pol.is), an online, crowdsourcing tool for understanding what large groups think. METHODS:Recruited via global peak bodies/networks, 99 individuals in the field of sexually transmitted infections (STIs) (43.4 % clinicians, 35.4% researchers) primarily from Australasia (41.4%), UK/Europe (29.3%) and North America (22.2%) participated. Ninety-one statements were submitted in favour/against reduced screening for GBMSM (eg, 'Bisexual men who don't test regularly risk putting women at risk'). Participants voted on submitted statements (agree/disagree/pass). Statements with ≥80% agreement were considered as 'strong' support, 70%-79% 'moderate' and ≤69% 'mixed'. Statements were grouped using content analysis to assess support for clusters of related statements. RESULTS:There was 'mixed support' for statements on: (1) the impact of screening in reducing prevalence; (2) whether asymptomatic infections pose clinical harm/necessitate treatment; and (3) risk of antimicrobial resistance. Statements advocating for 6-monthly screening received 'moderate support', with arguments centring on resource use. Participants 'strongly supported' the need for community engagement and maintaining frequent HIV/syphilis screening. CONCLUSIONS:While there were mixed opinions about relative utility, risks and harms of reducing chlamydia/gonorrhoea screening for GBMSM, arguments relating to resource constraints may provide common ground for policy changes.

Background:Syphilis is increasing worldwide, and secondary syphilis may represent its most infectious stage. Scarce data exist on Treponema pallidum clearance after treatment. We aimed to determine the frequency and load of T. pallidum mucosal shedding, and time to clearance following treatment of secondary syphilis. Methods:Men-who-have-sex-with-men (MSM) and transgender women with secondary syphilis were recruited from Australian clinics between January 27, 2023, and August 19, 2024. Oral, anal or genital lesions were swabbed, and non-lesion samples (blood, oral cavity and anal canal swabs were collected on the day of treatment (baseline). Non-lesion oral cavity and anal canal swabs were repeated 3, 7, 14 and 30 days post-treatment. T. pallidum bacterial load was determined by quantitative PCR. Findings:78 cis-men and one trans-woman, who reported sex with men, were included. At baseline, T. pallidum was detected in the participants' oral cavity, anal canal and blood of 81% (64/79), 70% (55/79) and 24% (19/79), respectively. When detected at oral and anal sites, 22/64 (36%) had oral lesions and 31/55 (59%) had anal lesions, respectively. The median oral and anal bacterial loads decreased significantly from baseline to day 3, [cycle thresholds 35.7-37.7, (1.7-1.2 copies/μL), (p = 0.013), and 30.2-38.2 (3.3-1.0 copies/μL), (p < 0.001), respectively]. T. pallidum cleared from 99% (96/97) of non-lesion, paired samples from 58 participants by day 7, 95% confidence interval (94-100%). Interpretation:During secondary syphilis, most MSM had T. pallidum DNA detected in oral and anal mucosa. Bacterial load dropped markedly 3 days post-treatment and cleared in almost all samples by 7 days. Funding:Australian National Health and Medical Research Council.

BACKGROUND:Culture remains essential for antimicrobial resistance profiling for gonorrhoea. However, the sensitivity of culture for gonorrhoea is low. This study aimed to compare positivity rates of culture for Neisseria gonorrhoeae using a gonococcus (GC) bi-plate containing selective and non-selective agar versus a single GC plate containing selective agar only, and assess the impact of clinician inoculation training and timing between a nucleic acid amplification test (NAAT) and culture on culture positivity. METHODS:A cross-sectional study was conducted at Melbourne Sexual Health Centre between April and June 2021. Clients undergoing gonorrhoea testing provided samples for both NAAT and culture, with alternating use of GC bi-plates and single GC plates over 2-week intervals. Clinicians received training on inoculation techniques before the study. A retrospective analysis of culture positivity before training was also performed. Culture positivity was compared between plate types, pre- and post-training, and across different time gaps between NAAT and culture. RESULTS:Among 276 clients included, there was no difference in culture positivity between GC bi-plate and single plate across all anatomical sites (P = 0.439). Oropharyngeal culture had the lowest positivity rates (44.3% bi-plate vs 36.2% single plate, P = 0.382). There was no significant difference in culture positivity before and after training staff on inoculation technique (P = 0.782), nor if the cultures were performed 1-5 days between positive NAAT and culture compared with 6-14 days. CONCLUSION:This study found no significant difference between GC bi-plate and GC single plate in detecting N. gonorrhoeae. Inoculation training and delayed culture post-NAAT did not significantly impact culture positivity. Improving culture methods remains critical for antimicrobial resistance surveillance.

Background:HIV testing uptake among men who have sex with men (MSM) in Australia remains suboptimal, with lapses and extended testing intervals persisting despite established guidelines. Novel HIV testing strategies address these gaps, particularly among MSM underserved by clinic-based services. We evaluated uptake of HIV self-testing (HIVST) distributed using social network-based strategies among MSM in Australia. Methods:In this prospective, non-randomised trial (ACTRN12625000342415), HIV-undiagnosed MSM aged ≥18 years were recruited online on a rolling basis between Jan 30 and April 28, 2025. Participants comprised both test promoters (initially recruited individuals who received HIVST kits for personal use and distribution) and recipients (individuals who received a kit from a promoter). Test promoters each received four HIVST kits-one for personal use and three for distribution. Participants were invited to complete an online survey within three months of kit receipt. Recipients who completed the survey could enrol as second-wave test promoters and receive additional kits. Primary outcome: HIVST use within 7 days of receipt; secondary outcomes: use within 24 h, feasibility and acceptability. Associations with use were estimated using Poisson regression. Findings:Ninety-one test promoters received 364 HIVST kits (91 for personal use, 273 for distribution). All promoters used their own kit and completed the follow-up survey (100%). Among the first-wave recipients, 245 kits were survey-verified as used. Eight recipients subsequently enrolled as second-wave test promoters, distributing additional kits and yielding 15 survey-verified secondary recipients. In total, 351 participants completed follow-up surveys. Of respondents, 280 (80%) used the HIVST within 7 days, including 181 (52%) within 24 h. Use within 7 days was more common among participants without government-subsidised healthcare (adjusted rate ratio 1.16, 1.05-1.28; p = 0.004), those not tested in the past 3 months (3-6 months, 1.22 [1.02-1.45], p = 0.026; 7-12 months, 1.36 [1.16-1.60], p < 0.001; >12 months, 1.30 [1.11-1.53], p = 0.001; never tested, 1.31 [1.11-1.55], p = 0.002), and those spending little (1.36 [1.10-1.68]; p = 0.004) or no time (1.33 [1.06-1.66]; p = 0.015) with LGBTQ+ peers. Most participants found HIVST easy to use (99%) and would reuse it (88%). Interpretation:Social network-based distribution of HIVST is feasible and acceptable, with high HIVST kit usability and rapid uptake among MSM, supporting equitable HIV testing access. Funding:Australian National Health and Medical Research Council (NHMRC) Emerging Leadership Investigator Grant and an Australian Government Research Training Program scholarship.

BACKGROUND:People living with HIV (PLHIV) are at increased risk of severe influenza-related complications, and annual vaccination is recommended. Uptake remains suboptimal and Australian data are limited. We assessed influenza vaccination uptake among PLHIV at a Melbourne specialist clinic and explored reasons for non-vaccination. METHODS:We conducted a repeated cross-sectional analysis of PLHIV attending the Melbourne Sexual Health Centre (MSHC), 2015-2025. Vaccination status was based on vaccines administered at the clinic. Segmented logistic regression assessed trends before and after the COVID-19 pandemic. A random sample of 1100 unvaccinated individuals (100/year) underwent chart review to identify reasons for non-vaccination, and an adjusted estimate incorporated self-reported external vaccination. RESULTS:Among 18,879 PLHIV records (median age 42, IQR 34-53), 39.6% (7474/18,879) were vaccinated at MSHC. Uptake rose from 40.4% (527/1305) in 2015 to 46.7% (779/1667) in 2019, fell to 22.9% (388/1691) in 2021, and partially recovered to 40.1% (891/2221) in 2025. Pre-pandemic uptake increased 4.8% annually (95% CI: 2.3-7.4, p < 0.001). After COVID-19 onset, vaccination odds were 65.5% lower than expected (95% CI: 60.9-69.7, p < 0.001), with subsequent annual increases of 20.3% (95% CI: 16.7-24.0). Of 1100 unvaccinated individuals reviewed, 40.6% (447) had no documented reason, 31.8% (350) reported vaccination elsewhere, and 13.5% (146) declined. Adjusted uptake including external vaccination was 58.6% (11,058/18,879). CONCLUSIONS:Influenza vaccination uptake among PLHIV in Melbourne remains suboptimal and was disrupted by the COVID-19 pandemic. External vaccination contributes substantially, so clinic records alone underestimate true uptake. Improved prompts, standardised documentation, and integration with the Australian Immunisation Register may optimise preventive care and better capture vaccination delivery.

BACKGROUND:Neisseria gonorrhoeae (NG) is one of the World Health Organization's high-priority bacterial pathogens due to the emergence of multidrug-resistant strains. The culture of NG remains important for providing antimicrobial resistance surveillance data. OBJECTIVE:To determine the NG culture yield following a positive NG nucleic acid amplification test (NAAT) within 30 days, stratified by culture specimen collection sites, the time interval between NAAT and culture, and gender. METHODS:A retrospective data analysis of positive NG NAAT specimens of individuals attending the Melbourne Sexual Health Centre between April 2015 and March 2023. We calculated the NG culture yield within 30 days and stratified by culture specimen collection sites. RESULTS:The NG culture yield was lowest in the pharynx (37.9%, 95% confidence interval (CI) 36.6-39.2, 1964/5185) followed by the vagina (41.6%, 95% CI 37.0-46.3, 186/447), cervix (60.1%, 95% CI 52.2-67.7, 98/163), rectum (68.0%, 95% CI 66.6-69.3, 3223/4742) and urethra (97.0%, 95% CI 96.4-97.6, 3282/3382). The overall NG culture yield was 77.8% (95% CI 76.8-78.8, 5254/6754) when the culture was performed on the same date as the NAAT test, and it decreased significantly to 53.6% (95% CI 51.5-55.7, 1193/2224) 1-3 days after the NAAT-positive specimens were collected, then to 37.1% (95% CI 30.7-43.7, 83/224) 15-30 days after the NAAT-positive specimens were collected (Ptrend <0.001). CONCLUSIONS:The culture specimen collection sites and time to culture collection influenced the culture yield. NG culture should be performed as close as possible to NAAT testing to improve NG culture yield. In addition, combining molecular resistance testing with culture-based techniques may be necessary to ensure adequate antimicrobial resistance detection.

BACKGROUND:Neisseria gonorrhoeae is a significant public health concern due to rising antimicrobial resistance. Current strategies for N gonorrhoeae among gay and bisexual men (GBM) include 3-month screening; however, high-frequency screening may increase ceftriaxone consumption, potentially contributing to antimicrobial resistance. METHODS:We conducted a retrospective cohort study of GBM screened for N gonorrhoeae at 16 Australian public sexual health services between 2016 and 2023. We classified N gonorrhoeae tests and ceftriaxone prescriptions as screening-related (asymptomatic screening) or nonscreening-related (testing/treatment of contacts, symptomatic testing, or empirical treatment). We explored trends in annual ceftriaxone prescription rates and used multivariable Poisson regression to examine the association between individuals' annual asymptomatic screening frequency and ceftriaxone consumption, adjusted for age, year, pre-exposure prophylaxis, HIV status, injecting drug use, and syphilis and chlamydia diagnoses. RESULTS:In total, 65 261 GBM contributed 133 846 person-years. From 2016 to 2023, the total ceftriaxone prescription rate rose from 2.92 defined daily doses per 100 person-years at risk to 5.25: screening-related ceftriaxone increased from 0.91 to 2.96 (P < .001) while nonscreening-related ceftriaxone remained stable (P = .570). When compared with having 1 screening test per year, having ≥4 tests was associated with a higher rate of screening-related ceftriaxone prescriptions (adjusted incident rate ratio, 5.47; 95% CI, 5.16-5.79). CONCLUSIONS:Ceftriaxone consumption rose among GBM, largely driven by increased screening rather than nonscreening-related treatment. Our findings highlight the association between high-frequency screening and antibiotic consumption, providing real-world data to guide discussions on the benefits and risks of screening.

INTRODUCTION:In Australia, cross-sectional estimates suggest that over 95% of people with HIV are virally suppressed; however, these measures reflect only the most recent viral load. Sustained viral suppression (SVS) is essential for optimizing health and preventing transmission. This study describes SVS among people with HIV who are engaged in care in Australia and factors associated with SVS. METHODS:We analyzed national data from the ACCESS sentinel surveillance system. Eligible participants attended an ACCESS clinic in 2023, received continuous antiretroviral therapy (ART; ≥1 prescription per calendar year), and had at least two viral load tests in the preceding three years (median:6; IQR: 5-7). SVS was defined as all viral load results less than 200 copies/ml. Multivariable logistic regression identified factors associated with SVS. RESULTS:Of 6036 eligible participants (95% men; median age 54 years), 5751 (95.3%) achieved SVS, while 99.1% were suppressed based on their last test. Older age (adjusted odds ratio [aOR]: 1.01; 95% confidence interval (95% CI): 1.002-1.03), residence in more socioeconomically advantaged areas (aOR: 1.06; 1.01-1.12), and higher mean CD4 + cell count (aOR: 1.00; 1.001-1.002) were associated with higher odds of SVS. Receiving care at publicly funded sexual health/hospital-based clinics (aOR:0.64; 0.48-0.86), more diagnoses of gonorrhea (aOR: 0.81; 0.67-0.96) or infectious syphilis in the last three years (aOR: 0.85; 0.73-0.98), and co-infection with hepatitis C in the last 3 years (aOR: 0.56; 0.36-0.87) were associated with lower SVS. CONCLUSIONS:More than 95% of people with HIV receiving ART and engaged in ongoing care achieved SVS. Strengthened, person-centered support for groups with lower SVS may enhance clinical outcomes and sustain Australia's progress toward HIV elimination goals.