Determining reinfection rates by hepatitis C testing interval among key populations: A systematic review and meta-analysis.

BACKGROUND & AIMS: Detecting hepatitis C virus (HCV) reinfection among key populations helps prevent ongoing transmission. This systematic review aims to determine the association between different testing intervals during post-SVR follow-up on the detection of HCV reinfection among highest risk populations. METHODS: We searched electronic databases between January 2014 and February 2023 for studies that tested individuals at risk for HCV reinfection at discrete testing intervals and reported HCV reinfection incidence among key populations. Pooled estimates of reinfection incidence were calculated by population and testing frequency using random-effects meta-analysis. RESULTS: Forty-one single-armed observational studies (9453 individuals) were included. Thirty-eight studies (8931 individuals) reported HCV reinfection incidence rate and were included in meta-analyses. The overall pooled estimate of HCV reinfection incidence rate was 4.13 per 100 per person-years (py) (95% confidence interval [CI]: 3.45-4.81). The pooled incidence estimate among people who inject drugs (PWID) was 2.84 per 100 py (95% CI: 2.19-3.50), among men who have sex with men (MSM) 7.37 per 100 py (95% CI: 5.09-9.65) and among people in custodial settings 7.23 per 100 py (95% CI: 2.13-16.59). The pooled incidence estimate for studies reporting a testing interval of ≤6 months (4.26 per 100 py; 95% CI: 2.86-5.65) was higher than studies reporting testing intervals >6 months (5.19 per 100 py; 95% CI: 3.92-6.46). CONCLUSIONS: HCV reinfection incidence was highest in studies of MSM and did not appear to change with retesting interval. Shorter testing intervals are likely to identify more reinfections, help prevent onward transmission where treatment is available and enable progress towards global HCV elimination, but additional comparative studies are required.

Time-to-hepatitis C treatment initiation among people who inject drugs in Melbourne, Australia.

This study aims to understand the time-to-treatment initiation pre and post DAA access to inform strategies to improve HCV care. The data for our study were derived from the SuperMIX cohort study of people who inject drugs in Melbourne, Australia. Time-to-event analysis using Weibull accelerated failure time was performed for data collected between 2009 and 2021, among a cohort of HCV-positive participants. Among 223 participants who tested positive for active hepatitis C infection, 102 people (45.7%) reported treatment initiation, with a median time-to-treatment of 7 years. However, the median time-to-treatment reduced to 2.3 years for those tested positive after 2016. The study found that treatment with Opioid Agonist Therapy (TR 0.7, 95% CI 0.6-0.9), engagement with health or social services (TR 0.7, 95% CI 0.6-0.9), and having a first positive HCV RNA test after March 2016 (TR 0.3, 95% CI 0.2-0.3) were associated with a reduced time-to-treatment initiation. The study highlights the need for strategies to improve engagement with health services, including drug treatment services into routine HCV care to achieve timely treatment.

Prevalence and incidence of emergency department presentations and hospital separations with injecting-related infections in a longitudinal cohort of people who inject drugs.

People who inject drugs are at risk of acute bacterial and fungal injecting-related infections. There is evidence that incidence of hospitalizations for injecting-related infections are increasing in several countries, but little is known at an individual level. We aimed to examine injecting-related infections in a linked longitudinal cohort of people who inject drugs in Melbourne, Australia. A retrospective descriptive analysis was conducted to estimate the prevalence and incidence of injecting-related infections using administrative emergency department and hospital separation datasets linked to the SuperMIX cohort, from 2008 to 2018. Over the study period, 33% (95%CI: 31-36%) of participants presented to emergency department with any injecting-related infections and 27% (95%CI: 25-30%) were admitted to hospital. Of 1,044 emergency department presentations and 740 hospital separations, skin and soft tissue infections were most common, 88% and 76%, respectively. From 2008 to 2018, there was a substantial increase in emergency department presentations and hospital separations with any injecting-related infections, 48 to 135 per 1,000 person-years, and 18 to 102 per 1,000 person-years, respectively. The results emphasize that injecting-related infections are increasing, and that new models of care are needed to help prevent and facilitate early detection of superficial infection to avoid potentially life-threatening severe infections.

Impact of COVID-19 lockdown restrictions on hepatitis C testing in Australian primary care services providing care for people who inject drugs.

In 2020, the Australian state of Victoria experienced the longest COVID-19 lockdowns of any jurisdiction, with two lockdowns starting in March and July, respectively. Lockdowns may impact progress towards eliminating hepatitis C through reductions in hepatitis C testing. To examine the impact of lockdowns on hepatitis C testing in Victoria, de-identified data were extracted from a network of 11 services that specialize in the care of people who inject drugs (PWID). Interrupted time-series analyses estimated weekly changes in hepatitis C antibody and RNA testing from 1 January 2019 to 14 May 2021 and described temporal changes in testing associated with lockdowns. Interruptions were defined at the weeks corresponding to the start of the first lockdown (week 14) and the start (week 80) and end (week 95) of the second lockdown. Pre-COVID, an average of 80.6 antibody and 25.7 RNA tests were performed each week. Following the first lockdown in Victoria, there was an immediate drop of 23.2 antibody tests and 8.6 RNA tests per week (equivalent to a 31% and 46% drop, respectively). Following the second lockdown, there was an immediate drop of 17.2 antibody tests and 4.6 RNA tests per week (equivalent to a 26% and 33% drop, respectively). With testing and case finding identified as a key challenge to Australia achieving hepatitis C elimination targets, the cumulative number of testing opportunities missed during lockdowns may prolong efforts to find, diagnose and engage or reengage in care of the remaining population of PWID living with hepatitis C.

Latent Class Analysis of Sexual Behaviours and Attitudes to Sexually Transmitted Infections Among Gay and Bisexual Men Using PrEP.

Gay and bisexual men (GBM) who use pre-exposure prophylaxis (PrEP) are at increased risk of sexually transmitted infections (STIs) compared to those who don't use PrEP. Since the implementation of PrEP in Australia, it is possible that attitudes towards STIs have shifted in line with changes in risk and transmission dynamics in the context of increased screening. As the extent to which GBM utilise STI prevention strategies likely depends on their attitudes towards STIs and STI prevention, the aims of this study were to use latent class analysis (LCA) to classify GBM using PrEP on the basis of their attitudes towards STIs and reported risk behaviours, and examine how these categorisations relate to risk of STI acquisition. 1225 GBM who were previously enrolled in a PrEP implementation study (The PrEPX Study) completed a survey focused on sexual behaviours and attitudes towards STIs 1 year post-study follow-up. Data on chlamydia, gonorrhoea and syphilis testing and positivity were available through a sentinel network of participating study clinics. Using LCA, participants were allocated into four classes; Class 1, "Some concern and lowest risk"; Class 2, "Low concern and lower risk"; Class 3, " High concern and higher risk"; and Class 4, "Low concern and highest risk". The majority (78%) of participants were classified into Class 3 or Class 4, two groups which were distinguished by highly disparate attitudes towards STIs but with a similar proportion of participants diagnosed with a bacterial STI in the last 12 months (48% and 57%, respectively). Findings suggest that attitudes towards STIs among GBM using PrEP in Australia vary considerably, and this will likely influence their receptivity to different STI prevention strategies.

Microelimination of Hepatitis C Among People With Human Immunodeficiency Virus Coinfection: Declining Incidence and Prevalence Accompanying a Multicenter Treatment Scale-up Trial.

BACKGROUND: Gay and bisexual men (GBM) are a key population affected by human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection. We aimed to measure HCV treatment effectiveness and to determine the population impact of treatment scale-up on HCV prevalence and incidence longitudinally among GBM. METHODS: The co-EC Study (Enhancing Care and Treatment Among HCV/HIV Coinfected Individuals to Eliminate Hepatitis C Transmission) was an implementation trial providing HCV direct-acting antiviral treatment in Melbourne, Australia, during 2016-2018. Individuals with HCV/HIV coinfection were prospectively enrolled from primary and tertiary care services. HCV viremic prevalence and HCV antibody/viremic incidence were measured using a statewide, linked, surveillance system. RESULTS: Among 200 participants recruited, 186 initiated treatment during the study period. Sustained virological response in primary care (98% [95% confidence interval {CI}, 93%-100%]) was not different to tertiary care (98% [95% CI, 86%-100%]). From 2012 to 2019, between 2434 and 3476 GBM with HIV infection attended our primary care sites annually, providing 13 801 person-years of follow-up; 50%-60% received an HCV test annually, and 10%-14% were anti-HCV positive. Among those anti-HCV positive, viremic prevalence declined 83% during the study (54% in 2016 to 9% in 2019). HCV incidence decreased 25% annually from 1.7/100 person-years in 2012 to 0.5/100 person-years in 2019 (incidence rate ratio, 0.75 [95% CI, .68-.83]; P < .001). CONCLUSIONS: High treatment effectiveness by nonspecialists demonstrates the feasibility of treatment scale-up in this population. Substantial declines in HCV incidence and prevalence among GBM provides proof-of-concept for HCV microelimination. CLINICAL TRIALS REGISTRATION: NCT02786758.

A New Method for Estimating the Incidence of Infectious Diseases.

Ambitious World Health Organization targets for disease elimination require monitoring of epidemics using routine health data in settings of decreasing and low incidence. We evaluated 2 methods commonly applied to routine testing results to estimate incidence rates that assume a uniform probability of infection between consecutive negative and positive tests based on 1) the midpoint of this interval and 2) a randomly selected point in this interval. We compared these with an approximation of the Poisson binomial distribution, which assigns partial incidence to time periods based on the uniform probability of occurrence in these intervals. We assessed bias, variance, and convergence of estimates using simulations of Weibull-distributed failure times with systematically varied baseline incidence and varying trend. We considered results for quarterly, half-yearly, and yearly incidence estimation frequencies. We applied the methods to assess human immunodeficiency virus (HIV) incidence in HIV-negative patients from the Treatment With Antiretrovirals and Their Impact on Positive and Negative Men (TAIPAN) Study, an Australian study of HIV incidence in men who have sex with men, between 2012 and 2018. The Poisson binomial method had reduced bias and variance at low levels of incidence and for increased estimation frequency, with increased consistency of estimation. Application of methods to real-world assessment of HIV incidence found decreased variance in Poisson binomial model estimates, with observed incidence declining to levels where simulation results had indicated bias in midpoint and random-point methods.

The Potential Impact of a Gel-Based Point-of-Sex Intervention in Reducing Gonorrhea Incidence Among Gay and Bisexual Men: A Modeling Study.

BACKGROUND: Increases in sexually transmitted infections among gay and bisexual men (GBM) over the past decade have coincided with declines in condom use and rapid uptake of HIV preexposure prophylaxis (PrEP). We explored the impact of an antimicrobial gel-based point-of-sex intervention (gel-PSI) with a lower efficacy for reducing gonorrhea transmission risk than condoms on population-level gonorrhea incidence among GBM in Victoria, Australia. METHODS: A deterministic compartmental model of HIV and gonorrhea transmission was used to project annual gonorrhea incidence from 2020 to 2025. Individuals were classified as HIV-negative (PrEP or non-PrEP users) or HIV-positive, and further stratified by gonorrhoea risk (high/low). All possible scenarios where between 0% and 100% of GBM using condoms transitioned to gel-PSI (considered a downgrade in protection) and 0% and 100% of GBM not using condoms transitioned to gel-PSI (considered an upgrade in protection), with gel-PSI efficacy ranging from 20% to 50%, were run. RESULTS: The baseline scenario of no gel-PSI uptake (status quo) projected 94,367 gonorrhea infections between 2020 and 2025, with an exponentially increasing trend in annual infections. For a gel-PSI efficacy of 30%, a net reduction in cumulative gonorrhea incidence was projected, relative to the status quo, for any ratio of proportion of condom users "downgrading" to proportion of noncondom users "upgrading" to gel-PSI use of less than 2.6. Under the supposition of equal proportions of condom users and noncondom users switching to gel-PSI, a relative reduction was projected for any gel-PSI efficacy greater than 16%. CONCLUSIONS: Our model suggests that the introduction of a gel-PSI could have benefits for controlling gonorrhea transmission among GBM, even in scenarios where the gel-PSI is considerably less efficacious than condoms and when gel-PSI uptake leads to consequent reductions in consistent condom use.

Association of HIV Preexposure Prophylaxis With Incidence of Sexually Transmitted Infections Among Individuals at High Risk of HIV Infection.

Importance: Emerging evidence suggests that risk of bacterial sexually transmitted infections (STIs) increases among gay and bisexual men following initiation of HIV preexposure prophylaxis (PrEP). Objective: To describe STI incidence and behavioral risk factors among a cohort of predominantly gay and bisexual men who use PrEP, and to explore changes in STI incidence following PrEP commencement. Design, Setting, and Participants: The Pre-exposure Prophylaxis Expanded (PrEPX) Study, a multisite, open-label intervention study, was nested within the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance (ACCESS) clinic network. A total of 4275 participants were enrolled (July 26, 2016-April 1, 2018) in Victoria, Australia. Of these, 2981 enrolled at 5 ACCESS clinics (3 primary care, 1 sexual health, and 1 community-based HIV rapid testing service), had at least 1 follow-up visit, and were monitored until April 30, 2018. Exposures: Upon enrollment, participants received daily oral tenofovir disoproxil fumurate and emtricitabine for HIV PrEP, quarterly HIV and STI testing, and clinical monitoring. Main Outcomes and Measures: The primary outcome was incidence of chlamydia, gonorrhea, or syphilis. Incidence rates and hazard ratios describing behavioral risk factors of STI diagnosis were calculated. Incidence rate ratios (IRRs), adjusted for change in testing frequency, described changes in STI incidence from 1-year preenrollment to study follow-up among participants with preenrollment testing data (n = 1378). Results: Among the 2981 individuals (median age, 34 years [interquartile range, 28-42]), 98.5% identified as gay or bisexual males, 29% used PrEP prior to enrollment, 89 (3%) withdrew and were censored at date of withdrawal, leaving 2892 (97.0%) enrolled at final follow-up. During a mean follow-up of 1.1 years (3185.0 person-years), 2928 STIs were diagnosed among 1427 (48%) participants (1434 chlamydia, 1242 gonorrhea, 252 syphilis). STI incidence was 91.9 per 100 person-years, with 736 participants (25%) accounting for 2237 (76%) of all STIs. Among 2058 participants with complete data for multivariable analysis, younger age, greater partner number, and group sex were associated with greater STI risk, but condom use was not. Among 1378 participants with preenrollment testing data, STI incidence increased from 69.5 per 100 person-years prior to enrollment to 98.4 per 100 person-years during follow-up (IRR, 1.41 [95% CI, 1.29-1.56]). After adjusting for testing frequency, the increase in incidence from 1 year preenrollment to follow-up was significant for any STI (adjusted IRR, 1.12 [95% CI, 1.02-1.23]) and for chlamydia (adjusted IRR, 1.17 [95% CI, 1.04-1.33]). Conclusions and Relevance: Among gay and bisexual men using PrEP, STIs were highly concentrated among a subset, and receipt of PrEP after study enrollment was associated with an increased incidence of STIs compared with preenrollment. These findings highlight the importance of frequent STI testing among gay and bisexual men using PrEP.

Effects of Pre-exposure Prophylaxis for the Prevention of Human Immunodeficiency Virus Infection on Sexual Risk Behavior in Men Who Have Sex With Men: A Systematic Review and Meta-analysis.

Background: Human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) is effective in reducing HIV risk in men who have sex with men (MSM). However, concerns remain that risk compensation in PrEP users may lead to decreased condom use and increased incidence of sexually transmitted infections (STIs). We assessed the impact of PrEP on sexual risk outcomes in MSM. Methods: We conducted a systematic review of open-label studies published to August 2017 that reported sexual risk outcomes in the context of daily oral PrEP use in HIV-negative MSM and transgender women. Pooled effect estimates were calculated using random-effects meta-analysis, and a qualitative review and risk of bias assessment were performed. Results: Sixteen observational studies and 1 open-label trial met selection criteria. Eight studies with a total of 4388 participants reported STI prevalence, and 13 studies with a total of 5008 participants reported change in condom use. Pre-exposure prophylaxis use was associated with a significant increase in rectal chlamydia (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.19-2.13) and an increase in any STI diagnosis (OR, 1.24; 95% CI, .99-1.54). The association of PrEP use with STI diagnoses was stronger in later studies. Most studies showed evidence of an increase in condomless sex among PrEP users. Conclusion: Findings highlight the importance of efforts to minimize STIs among PrEP users and their sexual partners. Monitoring of risk compensation among MSM in the context of PrEP scale-up is needed to assess the impact of PrEP on the sexual health of MSM and to inform preventive strategies.

The use of social networking platforms for sexual health promotion: identifying key strategies for successful user engagement.

BACKGROUND: Online social networking platforms such as Facebook and Twitter have grown rapidly in popularity, with opportunities for interaction enhancing their health promotion potential. Such platforms are being used for sexual health promotion but with varying success in reaching and engaging users. We aimed to identify Facebook and Twitter profiles that were able to engage large numbers of users, and to identify strategies used to successfully attract and engage users in sexual health promotion on these platforms. METHODS: We identified active Facebook (n = 60) and Twitter (n = 40) profiles undertaking sexual health promotion through a previous systematic review, and assessed profile activity over a one-month period. Quantitative measures of numbers of friends and followers (reach) and social media interactions were assessed, and composite scores used to give profiles an 'engagement success' ranking. Associations between host activity, reach and interaction metrics were explored. Content of the top ten ranked Facebook and Twitter profiles was analysed using a thematic framework and compared with five poorly performing profiles to identify strategies for successful user engagement. RESULTS: Profiles that were able to successfully engage large numbers of users were more active and had higher levels of interaction per user than lower-ranked profiles. Strategies used by the top ten ranked profiles included: making regular posts/tweets (median 46 posts or 124 tweets/month for top-ranked profiles versus six posts or six tweets for poorly-performing profiles); individualised interaction with users (85% of top-ranked profiles versus 0% for poorly-performing profiles); and encouraging interaction and conversation by posing questions (100% versus 40%). Uploading multimedia material (80% versus 30%) and highlighting celebrity involvement (70% versus 10%) were also key strategies. CONCLUSION: Successful online engagement on social networking platforms can be measured through quantitative (user numbers and interactions) and basic qualitative content analysis. We identified the amount and type of host activity as key strategies for success, and in particular, regular individualised interaction with users, encouraging conversation, uploading multimedia and relevant links, and highlighting celebrity involvement. These findings provide valuable insight for achieving a high level of online engagement through social networking platforms to support successful health promotion initiatives.

Effects of HIV antiretroviral therapy on sexual and injecting risk-taking behavior: a systematic review and meta-analysis.

BACKGROUND: Increased global access and use of antiretroviral therapy (ART) for human immunodeficiency virus (HIV) has been postulated to undermine HIV prevention efforts by changing individual risk-taking behavior. This review aims to determine whether ART use is associated with changes in sexual or injecting risk-taking behavior or diagnosis of sexually transmitted infections (STIs). METHODS: A systematic review and meta-analysis was conducted of HIV-seropositive participants receiving ART compared with no ART use in experimental or observational studies. Primary outcomes included (1) any unprotected sexual intercourse, (2) STI diagnoses, and (3) any unsafe injecting behavior. RESULTS: Fifty-eight studies met the selection criteria. Fifty-six studies containing 32 857 participants reported unprotected sex; 11 studies containing 16 138 participants reported STI diagnoses; and 4 studies containing 1600 participants reported unsafe injecting behavior. All included studies were observational. Unprotected sex was lower in participants receiving ART than in those not receiving ART (odds ratio [OR], 0.73; 95% confidence interval [CI], .64-.83; P < .001; heterogeneity I(2) = 79%) in both high-income (n = 38) and low-/middle-income country (n = 18) settings, without any evidence of publication bias. STI diagnoses were also lower among individuals on ART (OR, 0.58; 95% CI, .33-1.01; P = .053; I(2) = 92%); however, there was no difference in injecting risk-taking behavior with antiretroviral use (OR, 0.90; 95% CI, .60-1.35; P = .6; I(2) = 0%). CONCLUSIONS: Despite concerns that use of ART might increase sexual or injecting risk-taking, available research suggests that unprotected sex is reduced among HIV-infected individuals on treatment. The reasons for this are not yet clear, although self-selection and mutually reinforcing effects of HIV treatment and prevention messages among people on ART are likely.

Making the most of a brave new world: opportunities and considerations for using Twitter as a public health monitoring tool.

This paper outlines a commentary response to an article published by Young and colleagues in Preventive Medicine that evaluated the feasibility of using Twitter as a surveillance and monitoring took for HIV. We draw upon the broader literature on disease surveillance and public health prevention using social media and broader considerations of epidemiological and surveillance methods to provide readers with necessary considerations for using social media in epidemiology and surveillance.

Trends in chlamydia positivity among heterosexual patients from the Victorian Primary Care Network for Sentinel Surveillance, 2007-2011.

OBJECTIVE: To describe trends in chlamydia positivity from 2007 to 2011 among heterosexual people tested for chlamydia at selected clinics that provide services to people at high risk in Victoria, Australia. DESIGN: The Victorian Primary Care Network for Sentinel Surveillance is a prospective system that collates pathology results from laboratories and demographic and behavioural data from a questionnaire. SETTING: Two sexual health clinics and six other primary care clinics that target young people and women at high risk. PARTICIPANTS: All clients tested for chlamydia at sentinel clinics. Individuals aged less than 16 years, sex workers, or those reporting any same-sex sexual partners in the past 12 months were excluded from the analysis. MAIN OUTCOME MEASURES: Chlamydia positivity trends were assessed using three-level random-effects Poisson regression, with clinic and subject treated as nested random factors. Models were offset for total number of tests and adjusted for relevant covariates. RESULTS: Between 2007 and 2011, chlamydia positivity among 31 682 tests in women increased from 5.1% to 6.3%, and positivity among 23 771 tests in men increased from 7.4% to 8.2%. Adjusting for age, country of birth, number of sex partners, condom use, and presence of symptoms, chlamydia positivity increased between 2007 and 2011 significantly among women (incidence rate ratio [IRR], 1.29; 95% CI, 1.11-1.50) and non-significantly among men (IRR, 1.07; 95% CI, 0.92-1.23). Over time, a decrease in reported inconsistent condom use was also observed in both men and women; however, men became more likely to report more than one partner in the past year. CONCLUSION: We identified a concerning increase in chlamydia positivity over time, particularly among young women.

Same-visit hepatitis C testing and treatment to accelerate cure among people who inject drugs (the QuickStart Study): a cluster randomised cross-over trial protocol.

INTRODUCTION: Despite universal access to government-funded direct-acting antivirals (DAAs) in 2016, the rate of hepatitis C treatment uptake in Australia has declined substantially. Most hepatitis C is related to injecting drug use; reducing the hepatitis C burden among people who inject drugs (PWID) is, therefore, paramount to reach hepatitis C elimination targets. Increasing DAA uptake by PWID is important for interrupting transmission and reducing incidence, as well as reducing morbidity and mortality and improving quality of life of PWID and meeting Australia's hepatitis C elimination targets. METHODS AND ANALYSIS: A cluster randomised cross-over trial will be conducted with three intervention arms and a control arm. Arm A will receive rapid hepatitis C virus (HCV) antibody testing; arm B will receive rapid HCV antibody and rapid RNA testing; arm C will receive rapid HCV antibody testing and same-day treatment initiation for HCV antibody-positive participants; the control arm will receive standard of care. The primary outcomes will be (a) the proportion of participants with HCV commencing treatment and (b) the proportion of participants with HCV achieving cure. Analyses will be conducted on an intention-to-treat basis with mixed-effects logistic regression models. ETHICS AND DISSEMINATION: The study has been approved by the Alfred Ethics Committee (number HREC/64731/Alfred-2020-217547). Each participant will provide written informed consent. Reportable adverse events will be reported to the reviewing ethics committee. The findings will be presented at scientific conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05016609. TRIAL PROGRESSION: The study commenced recruitment on 9 March 2022 and is expected to complete recruitment in December 2024.

The sources of pharmaceuticals for problematic users of benzodiazepines and prescription opioids.

OBJECTIVES: To describe benzodiazepine and prescription opioid use by clients of drug treatment services and the sources of pharmaceuticals they use. DESIGN: Structured face-to-face interviews on unsanctioned use of benzodiazepines and prescription opioids were conducted between January and July 2008. PARTICIPANTS: Convenience sample of treatment entrants who reported regular (an average of ≥ 4 days per week) and unsanctioned use of benzodiazepines and/or prescription opioids over the 4 weeks before treatment entry. SETTING: Drug treatment services in Victoria, Queensland, Western Australia and Tasmania. MAIN OUTCOME MEASURES: Participant demographics, characteristics of recent substance use, substance use trajectories, and sources of pharmaceuticals. RESULTS: Two hundred and four treatment entrants were interviewed. Prescription opioids were predominantly obtained from non-prescribed sources (78%, 84/108). In contrast, medical practitioners were the main source for benzodiazepines (78%, 113/144). Forging of prescriptions was extremely uncommon. A mean duration of 6.3 years (SD, 6.6 years) for benzodiazepines and 4.4 years (SD, 5.7 years) for prescription opioids was reported between first use and problematic use--a substantial window for intervention. CONCLUSIONS: Medical practitioners are an important source of misused pharmaceuticals, but they are not the main source of prescription opioids. This has implications for prescription drug monitoring in Australia: current plans (to monitor only Schedule 8 benzodiazepines and prescription opioids) may have limited effects on prescription opioid users who use non-prescribed sources, and the omission of most benzodiazepines from monitoring programs may represent a lost opportunity for reducing unsanctioned use of benzodiazepines and associated harm.

Incidence and Prevalence of Hepatitis C Virus Among HIV-Negative Gay and Bisexual Men Using HIV Pre-exposure Prophylaxis (PrEP): A Systematic Review and Meta-analysis.

Background: Gay and bisexual men using HIV pre-exposure prophylaxis (PrEP) are at increased risk for sexually transmissible infections. Hepatitis C virus (HCV) risk among PrEP users is less clear. We explored HCV prevalence and incidence among cohorts of gay and bisexual men using PrEP and sources of heterogeneity across studies. Methods: This was a systematic review and meta-analysis of open-label PrEP studies to April 2022 reporting HCV prevalence at baseline or incidence during follow-up among gay and bisexual men using PrEP. Pooled prevalence and incidence estimates were calculated using random-effects meta-analysis, and subgroup analyses were performed by study- and country-level characteristics, including availability of HCV direct-acting antiviral (DAA) therapy at time of study. Results: Twenty-four studies from 9 countries were included, with a total sample of 24 733 gay and bisexual men. Pooled HCV antibody baseline prevalence was 0.97% (95% CI, 0.63%-1.31%), and pooled HCV RNA baseline prevalence was 0.38% (95% CI, 0.19%-0.56%). Among 19 studies reporting HCV incidence, incidence ranged from 0.0 to 2.93/100 person-years (py); the pooled estimate was 0.83/100py (95% CI, 0.55-1.11). HCV incidence was higher in 12 studies that began follow-up before broad DAA availability (1.27/100py) than in 8 studies that began follow-up after broad DAA availability (0.34/100py) and higher in studies in Europe compared with North America and Australia. Conclusions: Early reports of high HCV incidence among PrEP-using cohorts likely reflect enrollment of individuals based on specific risk-based eligibility criteria for smaller studies and enrollment before DAA scale-up. In contexts where both DAAs and PrEP have been implemented at scale, studies report lower HCV incidence. PrEP-specific HCV testing guidelines should be guided by local epidemiology.

The eliminate hepatitis C (EC) experience study: baseline characteristics of a cohort of people who inject drugs in Melbourne, Australia.

OBJECTIVES: Direct-acting antivirals provide an opportunity to eliminate hepatitis C virus (HCV) as a public health threat in Australia, yet barriers to care remain. In this study, we use baseline data from a longitudinal cohort of people who inject drugs to understand differences in participant characteristics and explore experiences of stigma, health service utilisation and health literacy between three care cascade groups. DESIGN: Cross-sectional. SETTING: Community and private primary healthcare services in Melbourne, Australia. PARTICIPANTS: Participants completed baseline surveys between 19 September 2018 and 15 December 2020. We recruited 288 participants; the median age was 42 years (IQR: 37-49 years) and 198 (69%) were male. At baseline, 103 (36%) self-reported being 'not engaged in testing', 127 (44%) had HCV RNA positivity but were 'not engaged in treatment' and 58 (20%) were 'engaged in HCV treatment'. OUTCOME MEASURES: Descriptive statistics were used to present the baseline demographics, health service utilisation and experiences of stigma data. We explored differences in these scales between participant demographics using χ2 test or fisher's exact tests, and differences between health literacy scores using one-way analysis of variance tests. RESULTS: A majority were in regular contact with multiple health services, and most had previously been identified as at-risk of HCV. In the 12 months preceding baseline, 70% reported any experiences of stigma related to injecting drug use. Assessment of health literacy data identified gaps for those 'not engaged in testing' and 'not engaged in treatment' across two relevant domains: 'ability to appraise health information' and 'ability to actively engage with healthcare providers'. CONCLUSION: In eliminate hepatitis C experience, lower HCV testing and treatment may be explained by experiences of stigmatisation or gaps in health literacy. Enhanced interventions targeting people who inject drugs to promote HCV care are needed.

Assessment of a primary care e-support package of automated case finding, simplified treatment algorithm and decision support to increase hepatitis B treatment uptake in primary care clinics in Australia (SIMPLY-B Study): protocol for a pilot evaluation.

INTRODUCTION: Despite the availability of effective, subsidised hepatitis B treatment, linkage to care and treatment rates remain very low globally. In Australia, specially trained primary care physicians (general practitioner, GPs) can prescribe hepatitis B treatment, however, most hepatitis B care occurs in specialist clinics. Increasing hepatitis B management by GPs in primary care clinics is essential to achieve national hepatitis B linkage to care and treatment targets by 2030.This pilot study determines the feasibility, acceptability and effectiveness of Simply B, a novel GP hepatitis B e-support package designed to increase hepatitis B management by GPs in primary care clinics. METHODS AND ANALYSIS: This study will be conducted in three parts:Part A: A prospective open-label pilot intervention study, comparing the proportion of people with hepatitis B who are managed by their GP in primary care clinics before, 12 months and 24 months after implementation of the Simply B electronic hepatitis B support package.Part B: A nested qualitative health services feasibility study using semistructured interviews and thematic analysisPart C: Cost-effectiveness analysis. ETHICS AND DISSEMINATION: This study has received ethics approval by St Vincent's Hospital. Data management and analysis will be centralised through the Department of Gastroenterology, St Vincent's Hospital. TRIAL REGISTRATION NUMBER: NCT05614466.