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BACKGROUND: Most studies assessing the HIV care cascade have typically been cross-sectional analyses, which do not capture the transition time to subsequent stages. We aimed to assess the longitudinal HIV cascade of care in Australia, and changes over time in transition times and associated factors. METHOD(S): In this longitudinal cohort study, we included linked data for gay and bisexual men (GBM) with a new HIV diagnosis who attended clinics participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance in New South Wales and Victoria between Jan 1, 2012, and Dec 31, 2019. We assessed three cascade transition periods: diagnosis to linkage to care (stage 1 transition); linkage to care to antiretroviral therapy (ART) initiation (stage 2 transition); and ART initiation to virological suppression (viral load <=200 copies per mL; stage 3 transition). We also calculated the probability of remaining virologically suppressed after the first recorded viral load of less than 200 copies per mL. We used the Kaplan-Meier method to estimate transition times and cumulative probability of stage transition. FINDINGS: We included 2196 GBM newly diagnosed with HIV between 2012 and 2019 contributing 6747 person-years of follow-up in our analysis. Median time from HIV diagnosis to linkage to care (stage 1 transition) was 2 days (IQR 1-3). Median time from linkage to care to ART initiation (stage 2 transition) was 33 days (30-35). Median time from ART initiation to first recorded virological suppression (stage 3 transition) was 49 days (47-52). The cumulative probability of ART initiation within 90 days of linkage to care increased from 36.9% (95% CI 32.9-40.6) in the 2012-13 calendar period to 94.1% (91.2-96.0) in the 2018-19 calendar period and cumulative probability of virological suppression within 90 days of ART initiation increased from 54.3% (48.8-59.3) in the 2012-13 calendar period to 82.9% (78.4-86.4) in the 2018-19 calendar period. 91.6% (90.1-9

Background: The Australian Collaboration for Coordinated Enhanced Sentinel Surveillance (ACCESS) was established to monitor national testing and test outcomes for blood-borne viruses (BBVs) and sexually transmissible infections (STIs) in key populations. ACCESS extracts deidentified data from sentinel health services that include general practice, sexual health, and infectious disease clinics, as well as public and private laboratories that conduct a large volume of BBV/STI testing. An important attribute of ACCESS is the ability to accurately link individual-level records within and between the participating sites, as this enables the system to produce reliable epidemiological measures. Objective: The aim of this study was to evaluate the use of GRHANITE software in ACCESS to extract and link deidentified data from participating clinics and laboratories. GRHANITE generates irreversible hashed linkage keys based on patient-identifying data captured in the patient electronic medical records (EMRs) at the site. The algorithms to produce the data linkage keys use probabilistic linkage principles to account for variability and completeness of the underlying patient identifiers, producing up to four linkage key types per EMR. Errors in the linkage process can arise from imperfect or missing identifiers, impacting the system's integrity. Therefore, it is important to evaluate the quality of the linkages created and evaluate the outcome of the linkage for ongoing public health surveillance. Methods: Although ACCESS data are deidentified, we created two gold-standard datasets where the true match status could be confirmed in order to compare against record linkage results arising from different approaches of the GRHANITE Linkage Tool. We reported sensitivity, specificity, and positive and negative predictive values where possible and estimated specificity by comparing a history of HIV and hepatitis C antibody results for linked EMRs. Results: Sensitivity ranged from 96% to

Background Hepatitis C elimination will require widespread access to treatment and responses at the health-service level to increase testing among populations at risk. We explored changes in hepatitis C testing and the cascade of care before and after the introduction of direct-Acting antiviral treatments in Victoria, Australia. Methods De-identified clinical data were retrospectively extracted from eighteen primary care clinics providing services targeted towards people who inject drugs. We explored hepatitis C testing within three-year periods immediately prior to (pre-DAA period) and following (post-DAA period) universal access to DAA treatments on 1st March 2016. Among ever RNA-positive individuals, we constructed two care cascades at the end of the pre-DAA and post-DAA periods. Results The number of individuals HCV-Tested was 13,784 (12.2% of those with a consultation) in the pre-DAA period and 14,507 (10.4% of those with a consultation) in the post-DAA period. The pre-DAA care cascade included 2,515 RNA-positive individuals; 1,977 (78.6%) were HCV viral load/genotype tested; 19 (0.8%) were prescribed treatment; and 12 had evidence of cure (0.5% of those RNA-positive and 63.6% of those eligible for cure). The post-DAA care cascade included 3,713 RNA-positive individuals; 3,276 (88.2%) were HCV viral load/ genotype tested; 1,674 (45.1%) were prescribed treatment; and 863 had evidence of cure (23.2% of those RNA-positive and 94.9% of those eligible for cure). Conclusion Marked improvements in the cascade of hepatitis C care among patients attending primary care clinics were observed following the universal access of DAA treatments in Australia, although improvements in testing were less pronounced.

Background Globally, few studies compare progress toward the Joint United Nations Program on HIV/ AIDS (UNAIDS) Fast-Track targets among migrant populations. Fast-Track targets are aligned to the HIV diagnosis and care cascade and entail achieving 90-90-90 (90% of people living with HIV [PLHIV] diagnosed, 90% of those diagnosed on treatment, and 90% of those on treatment with viral suppression [VS]) by 2020 and 95-95-95 by 2030. We compared cascades between migrant and nonmigrant populations in Australia. Methods and findings We conducted a serial cross-sectional survey for HIV diagnosis and care cascades using modelling estimates for proportions diagnosed combined with a clinical database for proportions on treatment and VS between 2013-2017. We estimated the number of PLHIV and number diagnosed using New South Wales (NSW) and Victorian (VIC) data from the Australian National HIV Registry. Cascades were stratified by migration status, sex, HIV exposure, and eligibility for subsidised healthcare in Australia (reciprocal healthcare agreement [RHCA]). We found that in 2017, 17,760 PLHIV were estimated in NSW and VIC, and 90% of them were males. In total, 90% of estimated PLHIV were diagnosed. Of the 9,391 who were diagnosed and retained in care, most (85%; n = 8,015) were males. We excluded 38% of PLHIV with missing data for country of birth, and 41% (n = 2,408) of eligible retained PLHIV were migrants. Most migrants were from Southeast Asia (SEA; 28%), northern Europe (12%), and eastern Asia (11%). Most of the migrants and nonmigrants were males (72% and 83%, respectively). We found that among those retained in care, 90% were on antiretroviral therapy (ART), and 95% of those on ART had VS (i.e., 90-90-95). Migrants had larger gaps in their HIV diagnosis and care cascade (85-85-93) compared with nonmigrants (94-90-96). Similarly, there were larger gaps among migrants reporting male-to-male HIV exposure (84-83-93) compared with nonmigrants reporting male-to-male HIV ex

BACKGROUND: Globally, few studies compare progress toward the Joint United Nations Program on HIV/AIDS (UNAIDS) Fast-Track targets among migrant populations. Fast-Track targets are aligned to the HIV diagnosis and care cascade and entail achieving 90-90-90 (90% of people living with HIV [PLHIV] diagnosed, 90% of those diagnosed on treatment, and 90% of those on treatment with viral suppression [VS]) by 2020 and 95-95-95 by 2030. We compared cascades between migrant and nonmigrant populations in Australia. METHODS AND FINDINGS: We conducted a serial cross-sectional survey for HIV diagnosis and care cascades using modelling estimates for proportions diagnosed combined with a clinical database for proportions on treatment and VS between 2013-2017. We estimated the number of PLHIV and number diagnosed using New South Wales (NSW) and Victorian (VIC) data from the Australian National HIV Registry. Cascades were stratified by migration status, sex, HIV exposure, and eligibility for subsidised healthcare in Australia (reciprocal healthcare agreement [RHCA]). We found that in 2017, 17,760 PLHIV were estimated in NSW and VIC, and 90% of them were males. In total, 90% of estimated PLHIV were diagnosed. Of the 9,391 who were diagnosed and retained in care, most (85%; n = 8,015) were males. We excluded 38% of PLHIV with missing data for country of birth, and 41% (n = 2,408) of eligible retained PLHIV were migrants. Most migrants were from Southeast Asia (SEA; 28%), northern Europe (12%), and eastern Asia (11%). Most of the migrants and nonmigrants were males (72% and 83%, respectively). We found that among those retained in care, 90% were on antiretroviral therapy (ART), and 95% of those on ART had VS (i.e., 90-90-95). Migrants had larger gaps in their HIV diagnosis and care cascade (85-85-93) compared with nonmigrants (94-90-96). Similarly, there were larger gaps among migrants reporting male-to-male HIV exposure (84-83-93) compared with nonmigrants reporting male-to-male HIV e

BACKGROUND: Hepatitis C elimination will require widespread access to treatment and responses at the health-service level to increase testing among populations at risk. We explored changes in hepatitis C testing and the cascade of care before and after the introduction of direct-acting antiviral treatments in Victoria, Australia. METHODS: De-identified clinical data were retrospectively extracted from eighteen primary care clinics providing services targeted towards people who inject drugs. We explored hepatitis C testing within three-year periods immediately prior to (pre-DAA period) and following (post-DAA period) universal access to DAA treatments on 1st March 2016. Among ever RNA-positive individuals, we constructed two care cascades at the end of the pre-DAA and post-DAA periods. RESULTS: The number of individuals HCV-tested was 13,784 (12.2% of those with a consultation) in the pre-DAA period and 14,507 (10.4% of those with a consultation) in the post-DAA period. The pre-DAA care cascade included 2,515 RNA-positive individuals; 1,977 (78.6%) were HCV viral load/genotype tested; 19 (0.8%) were prescribed treatment; and 12 had evidence of cure (0.5% of those RNA-positive and 63.6% of those eligible for cure). The post-DAA care cascade included 3,713 RNA-positive individuals; 3,276 (88.2%) were HCV viral load/genotype tested; 1,674 (45.1%) were prescribed treatment; and 863 had evidence of cure (23.2% of those RNA-positive and 94.9% of those eligible for cure). CONCLUSION: Marked improvements in the cascade of hepatitis C care among patients attending primary care clinics were observed following the universal access of DAA treatments in Australia, although improvements in testing were less pronounced.

BACKGROUND: It is estimated that approximately half of new HIV diagnoses among heterosexual migrants in Victoria, Australia, were acquired post-migration. We investigated the characteristics of phylogenetic clusters in notified cases of HIV among heterosexual migrants. METHODS: Partial HIV pol sequences obtained from routine clinical genotype tests were linked to Victorian HIV notifications with the following exposures listed on the notification form: heterosexual sexual contact, injecting drug use, bisexual sexual contact, male-to male sexual contact or heterosexual sexual contact in combination with injecting drug use, unknown exposure. Those with heterosexual sexual contact as the only exposure were the focus of this study, with the other exposures included to better understand transmission networks. Additional reference sequences were extracted from the Los Alamos database. Maximum likelihood methods were used to infer the phylogeny and the robustness of the resulting tree was assessed using bootstrap analysis. Phylogenetic clusters were defined on the basis of bootstrap and genetic distance. RESULTS: HIV pol sequences were available for 332 of 445 HIV notifications attributed to only heterosexual sexual contact in Victoria from 2005-2014. Forty-three phylogenetic clusters containing at least one heterosexual migrant were detected, 30 (70%) of which were pairs. The characteristics of these phylogenetic clusters varied considerably by cluster size. Pairs were more likely to be composed of people living with HIV from a single country of birth (p = 0.032). Larger clusters (n≥3) were more likely to contain people born in Australian/New Zealand (p = 0.002), migrants from more than one country of birth (p = 0.013) and viral subtype-B, the most common subtype in Australia (p = 0.006). Pairs were significantly more likely to contain females (p = 0.037) and less likely to include HIV diagnoses with male-to-male sexual contact reported as a possible exposure (p<0.001) com

Few studies investigate sexual health among Chinese international students in Australia. We recruited domestic (n = 623) and Chinese international (n = 500) students for separate online surveys on sexual behaviours and knowledge. Samples were compared using Chi square, Fisher's exact and equality of medians tests. Domestic students were more likely than international students to have ever touched a partner's genitals (81% vs. 53%, p < 0.01), had oral sex (76% vs. 44%, p < 0.01), vaginal intercourse (67% vs. 41%, p < 0.01) and anal intercourse (31% vs. 6%, p < 0.01). Domestic students were younger when they first touched a partner's genitals (16 vs. 18 years, p < 0.01), had oral sex (17 vs. 18 years, p < 0.01) and vaginal intercourse (17 vs. 18 years, p < 0.01). Domestic students were less likely than Chinese international students to report only one lifetime partner for touching genitals (22% vs. 50%, p < 0.01), oral sex (25% vs. 55%, p < 0.01), vaginal intercourse (30% vs. 58%, p < 0.01) and anal intercourse (54% vs. 88%, p < 0.01). Domestic students were more likely than Chinese international students to use the oral contraceptive pill (48% vs. 16%, p < 0.01) and long-acting reversible contraceptives (19% vs. 1%, p < 0.01). Domestic students scored higher than international students on a contraception and chlamydia quiz (4/5 vs. 2/5, p < 0.01). Domestic and Chinese international students differed in sexual behaviours and knowledge highlighting the need for relevant sexual health promotion for both groups.

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 numb

Background: A priority area in the 2016 Victorian Hepatitis B Strategy is to increase diagnostic testing. This study describes hepatitis B testing and positivity trends in Victoria between 2011 and 2016 using data from a national laboratory sentinel surveillance system. Methods: Line-listed diagnostic and monitoring hepatitis B testing data among Victorian individuals were collated from six laboratories participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance (ACCESS) of sexually transmissible infections and blood-borne viruses. Diagnostic tests included hepatitis B surface antigen (HBsAg)-only tests and guideline-based hepatitis B tests (defined as a single test event for HBsAg, hepatitis B surface antibody and hepatitis B core antibody). Using available data, the outcomes of testing and/or infection were further classified. Measures reported include the total number of HBsAg and guideline-based tests conducted and the proportion positive, classified as either HBsAg positive or chronic hepatitis B infection. Results: The number of HBsAg tests decreased slightly each year between 2011 and 2016 (from 91 043 in 2011 to 79 664 in 2016; P < 0.001), whereas the number of guideline-based hepatitis B tests increased (from 8732 in 2011 to 16 085 in 2016; P <0.001). The proportion of individuals classified as having chronic infection decreased from 25% in 2011 to 7% in 2016, whereas the proportion classified as susceptible and immune due to vaccination increased (from 29% to 39%, and from 27% to 34%, respectively; P < 0.001). Conclusions: The study findings indicate an increased uptake of guideline-based hepatitis B testing. The ongoing collection of testing data can help monitor progress towards implementation of the Victorian Hepatitis B Strategy.

In 2018, University of Melbourne and Burnet Institute conducted the survey Intimate attitudes, practices and knowledges: Chinese-speaking international students in Australia. This study aimed to generate data on Chinese international students’ sexual experiences in order to inform sexual health service provision in Australia. We provide this summary report as a resource and reference for future work in this area. The survey was open for nine weeks and completed by 723 Chinese-speaking international students. Participants were aged 16 years and over, self-identified as Chinese-speaking international students, and were studying across Australia iin high schools, universities, language schools, foundation studies courses, and the Vocational Education and Training (VET) and Technical and Further Education (TAFE) sectors. The majority (96%) of participants were from the mainland of the People’s Republic of China, and almost half (47%) had been in Australia for less than a year. The median age of participants was 22 years and most identified as female (69%).

BACKGROUND: HIV and bacterial sexually transmissible infection (STI) notifications among men who have sex with men (MSM) have increased in Australia and many other countries. The relationship between HIV infection and other STIs has been demonstrated previously. However, the relationship between the cumulative history of STIs and subsequent HIV infection remains largely unexplored and limits our understanding of the mechanisms underpinning the elevated HIV risk. METHODS: Data from HIV-negative MSM who attended high-HIV caseload primary care clinics in Melbourne, Australia, from 2007 to 2014 with 2 or more HIV and STI tests were included. Controlling for sexual behaviors self-reported at clinic visits, discrete time survival analyses using generalized linear modeling estimated the effect of an STI at the prior test event and the cumulative history of STIs (none, 1, 2, or more [repeated]) on risk of HIV infection. RESULTS: A total of 8941 MSM met the study criteria; 227 (2.5%) were diagnosed with HIV over the follow-up period. Adjusting for sexual behaviors, a cumulative history of repeated rectal gonorrhea infections (adjusted hazard ratio [aHR], 6.27; 95% confidence interval [CI], 2.68-14.50) and a single rectal gonorrhea infection (aHR, 2.09; 95% CI, 1.15-3.79) were associated with increased HIV infection risk. CONCLUSIONS: Repeated and single rectal gonorrhea infections were independently associated with increased HIV infection risk. These findings suggest that MSM with any history of rectal gonorrhea, particularly repeat rectal gonorrhea, represent a group for whom preventive interventions for HIV should be emphasized.

Background: In Australia, clinical trial drugs are conventionally dispensed through clinical trial pharmacies only, while community pharmacies dispense drugs approved by Australia's regulatory body. A large HIV pre-exposure prophylaxis study aimed to deliver clinical trial drug through community pharmacies to improve convenience and mimic real world prescribing. This paper describes the process of making community trials compliant with good clinical practice and reports outcomes of delivering clinical trial drug through community pharmacies. Methods: Eight community and four clinical trial pharmacies across three Australian states were approached to participate. A good clinical practice checklist was generated and pharmacies underwent a number of changes to meet clinical trial pharmacy requirements prior to study opening. Changes were made to community pharmacies to make them compliant with good clinical trial practice including; staff training, structural changes, and implementing monitoring of study drug and prescribing practices. Study drug was ordered through standard clinical trial processes and dispensed from study pharmacies by accredited pharmacists. Throughout the trial, record logs for training, prescriber signature and delegation, temperature, participant, and drug accountability were maintained at each pharmacy. The study team monitored each log and delivered on-site training to correct protocol variations. Results: Each pharmacy that was approached agreed to participate. All community pharmacies achieved good clinical practice compliance prior to dispensing study drug. Over the course of the study, 20,152 dispensations of study drug occurred, 83% of these occurred at community pharmacies. Only 2.0% of dispensations had an error, and errors were predominantly minor. On five occasions a pharmacist who was not accredited dispensed study drug. Conclusions: Community based pharmacies can undergo training and modifications to achieve good clinical practice co

Background: Pre-exposure prophylaxis (PrEP) is the use of HIV anti-retroviral therapy to prevent HIV transmission in people at high risk of HIV acquisition. PrEP is highly efficacious when taken either daily, or in an on-demand schedule. In Australia co-formulated tenofovir-emtricitabine is registered for daily use for PrEP, however, this co-formulation is not listed yet on the national subsidized medicines list. We describe a study protocol that aims to demonstrate if the provision of PrEP to up to 3800 individuals at risk of HIV in Victoria, Australia reduces HIV incidence locally by 25% generally and 30% among GBM. Methods: PrEPX is a population level intervention study in Victoria, Australia in which generic PrEP will be delivered to 3800 individuals for up to 36 months. Study eligibility is consistent with the recently updated 2017 Australian PrEP guidelines. Participants will attend study clinics, shared care clinics, or outreach clinics for quarterly HIV/STI screening, biannual renal function tests and other clinical care as required. Study visits and STI diagnoses will be recorded electronically through the ACCESS surveillance system. At each study visit participants will be invited to complete behavioral surveys that collect demographics and sexual risk data. Diagnosis and behavioral data will be compared between PrEPX participants and other individuals testing within the ACCESS surveillance system. A subset of participants will complete in depth surveys and interviews to collect attitudes, beliefs and acceptability data. Participating clinics will provide clinic level data on implementation and management of PrEPX participants. The population level impact on HIV incidence will be assessed using Victorian HIV notification data. Discussion: This study will collect evidence on the real world impact of delivery of PrEP to 3800 individuals at risk of acquiring HIV in Victoria. This study will provide important information for the broader implementation of PrEP

Background: In Australia, new HIV diagnoses increasingly occur among people who do not report male-to-male sex. Among migrants, it is not clear what proportion acquired infection before migration. Similarly, among Australian-born people, it is not clear what proportion acquired infection in-country. There is a need to better understand the epidemiology of HIV in people who do not report male-to-male sex. Method(s): Victorian public health surveillance data were used to classify migrants as having likely acquired HIV before or after arrival to Australia using a CD4 cell count decline method to estimate date of infection. Place of exposure for Australian-born people was estimated based on self-report. Factors associated with place of HIV acquisition, advanced infection and newly acquired infection were explored among migrants and among Australian-born people. Result(s): Between July 1996 and June 2014, there were 821 new non-MSM HIV diagnoses. Most (58%) were migrants, and of these, half (54%) were estimated to have acquired HIV before migration. Among Australian-born people, 27% reported exposure likely occurring abroad; the majority of these were men who reported exposure in South-East Asia. Advanced infection was common in migrants (45%) and Australian-born people (35%). Among migrants, birth in South-East Asia was associated with increased odds of advanced infection. Conclusion(s): These results highlight the potential vulnerability of migrants after arrival in Australia, especially those from South-East Asia and Sub-Saharan Africa, and that of Australian-born men travelling to these regions. Public health practice must be strengthened to meet prevention needs of these populations in line with Australian policy.Copyright © 2018 CSIRO.

INTRODUCTION: Outbreaks of hepatitis C virus (HCV) infections among HIV-positive men who have sex with men (MSM) have been observed globally. Using a multi-modelling approach we estimate the time and number of direct-acting antiviral treatment courses required to achieve an 80% reduction in HCV prevalence among HIV-positive MSM in the state of Victoria, Australia. METHODS: Three models of HCV transmission, testing and treatment among MSM were compared: a dynamic compartmental model; an agent-based model (ABM) parametrized to local surveillance and behavioural data ("ABM1"); and an ABM with a more heterogeneous population ("ABM2") to determine the influence of extreme variations in sexual risk behaviour. RESULTS: Among approximately 5000 diagnosed HIV-positive MSM in Victoria, 10% are co-infected with HCV. ABM1 estimated that an 80% reduction in HCV prevalence could be achieved in 122 (inter-quartile range (IQR) 112 to 133) weeks with 523 (IQR 479 to 553) treatments if the average time from HCV diagnosis to treatment was six months. This was reduced to 77 (IQR 69 to 81) weeks if the average time between HCV diagnosis and treatment commencement was decreased to 16 weeks. Estimates were consistent across modelling approaches; however ABM2 produced fewer incident HCV cases, suggesting that treatment-as-prevention may be more effective in behaviourally heterogeneous populations. CONCLUSIONS: Major reductions in HCV prevalence can be achieved among HIV-positive MSM within two years through routine HCV monitoring and prompt treatment as a part of HIV care. Compartmental models constructed with limited behavioural data are likely to produce conservative estimates compared to models of the same setting with more complex parametrizations.

Background Understanding retention and loss to follow up in HIV care, in particular the number of people with unknown outcomes, is critical to maximise the benefits of antiretroviral therapy. Individual-level data are not available for these outcomes in Australia, which has an HIV epidemic predominantly focused amongst men who have sex with men. Methods and Findings A network of the 6 main HIV clinical care sites was established in the state of Victoria, Australia. Individuals who had accessed care at these sites between February 2011 and June 2013 as assessed by HIV viral load testing but not accessed care between June 2013 and February 2014 were considered individuals with potentially unknown outcomes. For this group an intervention combining cross-referencing of clinical data between sites and phone tracing individuals with unknown outcomes was performed. 4966 people were in care in the network and before the intervention estimates of retention ranged from 85.9%-95.8% and the proportion with unknown outcomes ranged from 1.3-5.5%. After the intervention retention increased to 91.4-98.8% and unknown outcomes decreased to 0.1-2.4% (p<.01 for all sites for both outcomes). Most common reasons for disengagement from care were being too busy to attend or feeling well. For those with unknown outcomes prior to the intervention documented active psychiatric illness at last visit was associated with not re-entering care (p = 0.04) Conclusions The network demonstrated low numbers of people with unknown outcomes and high levels of retention in care. Increased levels of retention in care and reductions in unknown outcomes identified after the intervention largely reflected confirmation of clinic transfers while a smaller number were successfully re-engaged in care. Factors associated with disengagement from care were identified. Systems to monitor patient retention, care transfer and minimize disengagement will maximise individual and population-level outcomes for populations

OBJECTIVES: HIV diagnoses among men who have sex with men (MSM) in several high-income countries, including Australia, have increased substantially over recent years. Australia, in line with global prevention strategies, has emphasised a 'test and treat' HIV prevention strategy which relies on timely detection of HIV through frequent testing by those at risk. We examined trends in repeat testing among MSM defined as 'high-risk' according to Australian testing guidelines. METHODS: HIV test records from MSM attending high caseload clinics in Melbourne 2007-2013 and classified as high-risk were analysed. Binary outcomes of 'test within 3 months' and 'test within 6 months' were assigned to tests within individuals' panel of records. Negative binomial regressions assessed trends in overall HIV testing and returning within 3 and 6 months. Annualised proportions of return tests (2007-2012) were compared using two-sample z tests. RESULTS: Across 18 538 tests among 7117 high-risk MSM attending primary care clinics in Melbourne (2007-2013), the number of annual HIV tests increased (p<0.01). Between 2007 and 2012 annualised proportions of tests with a subsequent test within 3 and 6 months also increased (p<0.01); however, by 2012 only 36.4% and 15.1% of tests were followed by another test inside 6 and 3 months, respectively. CONCLUSIONS: Repeat testing among high-risk MSM in Australia remains unacceptably low, with recent modest increases in testing unlikely to deliver meaningful prevention impact. Removing known barriers to HIV testing is needed to maximise the potential benefit of test and treat-based HIV prevention.

Objectives Directly measuring disease incidence in a population is difficult and not feasible to do routinely. We describe the development and application of a new method for estimating at a population level the number of incident genital chlamydia infections, and the corresponding incidence rates, by age and sex using routine surveillance data. Methods A Bayesian statistical approach was developed to calibrate the parameters of a decisionpathway tree against national data on numbers of notifications and tests conducted (2001-2013). Independent beta probability density functions were adopted for priors on the time-independent parameters; the shapes of these beta parameters were chosen to match prior estimates sourced from peer-reviewed literature or expert opinion. To best facilitate the calibration, multivariate Gaussian priors on (the logistic transforms of ) the time-dependent parameters were adopted, using the Matern covariance function to favour small changes over consecutive years and across adjacent age cohorts. The model outcomes were validated by comparing them with other independent empirical epidemiological measures, that is, prevalence and incidence as reported by other studies. Results Model-based estimates suggest that the total number of people acquiring chlamydia per year in Australia has increased by ~120% over 12 years. Nationally, an estimated 356 000 people acquired chlamydia in 2013, which is 4.3 times the number of reported diagnoses. This corresponded to a chlamydia annual incidence estimate of 1.54% in 2013, increased from 0.81% in 2001 (¡90% increase). Conclusions We developed a statistical method which uses routine surveillance (notifications and testing) data to produce estimates of the extent and trends in chlamydia incidence.

BACKGROUND: Understanding retention and loss to follow up in HIV care, in particular the number of people with unknown outcomes, is critical to maximise the benefits of antiretroviral therapy. Individual-level data are not available for these outcomes in Australia, which has an HIV epidemic predominantly focused amongst men who have sex with men. METHODS AND FINDINGS: A network of the 6 main HIV clinical care sites was established in the state of Victoria, Australia. Individuals who had accessed care at these sites between February 2011 and June 2013 as assessed by HIV viral load testing but not accessed care between June 2013 and February 2014 were considered individuals with potentially unknown outcomes. For this group an intervention combining cross-referencing of clinical data between sites and phone tracing individuals with unknown outcomes was performed. 4966 people were in care in the network and before the intervention estimates of retention ranged from 85.9%-95.8% and the proportion with unknown outcomes ranged from 1.3-5.5%. After the intervention retention increased to 91.4-98.8% and unknown outcomes decreased to 0.1-2.4% (p<.01 for all sites for both outcomes). Most common reasons for disengagement from care were being too busy to attend or feeling well. For those with unknown outcomes prior to the intervention documented active psychiatric illness at last visit was associated with not re-entering care (p = 0.04). CONCLUSIONS: The network demonstrated low numbers of people with unknown outcomes and high levels of retention in care. Increased levels of retention in care and reductions in unknown outcomes identified after the intervention largely reflected confirmation of clinic transfers while a smaller number were successfully re-engaged in care. Factors associated with disengagement from care were identified. Systems to monitor patient retention, care transfer and minimize disengagement will maximise individual and population-level outcomes for populati