Modelling response strategies for controlling gonorrhoea outbreaks in men who have sex with men in Australia.

The ability to treat gonorrhoea with current first-line drugs is threatened by the global spread of extensively drug resistant (XDR) Neisseria gonorrhoeae (NG) strains. In Australia, urban transmission is high among men who have sex with men (MSM) and importation of an XDR NG strain in this population could result in an epidemic that would be difficult and costly to control. An individual-based, anatomical site-specific mathematical model of NG transmission among Australian MSM was developed and used to evaluate the potential for elimination of an imported NG strain under a range of case-based and population-based test-and-treat strategies. When initiated upon detection of the imported strain, these strategies enhance the probability of elimination and reduce the outbreak size compared with current practice (current testing levels and no contact tracing). The most effective strategies combine testing targeted at regular and casual partners with increased rates of population testing. However, even with the most effective strategies, outbreaks can persist for up to 2 years post-detection. Our simulations suggest that local elimination of imported NG strains can be achieved with high probability using combined case-based and population-based test-and-treat strategies. These strategies may be an effective means of preserving current treatments in the event of wider XDR NG emergence.

Declining hepatitis C virus-related liver disease burden in the direct-acting antiviral therapy era in New South Wales, Australia.

BACKGROUND & AIMS: Population-level evidence for the impact of direct-acting antiviral (DAA) therapy on hepatitis C virus (HCV)-related disease burden is lacking. We aimed to evaluate trends in HCV-related decompensated cirrhosis and hepatocellular carcinoma (HCC) hospitalisation, and liver-related and all-cause mortality in the pre-DAA (2001-2014) and DAA therapy (2015-2017) eras in New South Wales, Australia. METHODS: HCV notifications (1993-2016) were linked to hospital admissions (2001-2017) and mortality (1995-2017). Segmented Poisson regressions and Poisson regression were used to assess the impact of DAA era and factors associated with liver-related mortality, respectively. RESULTS: Among 99,910 people with an HCV notification, 3.8% had a decompensated cirrhosis diagnosis and 1.8% had an HCC diagnosis, while 3.3% and 10.5% died of liver-related and all-cause mortality, respectively. In the pre-DAA era, the number of decompensated cirrhosis and HCC diagnoses, and liver-related and all-cause mortality consistently increased (incidence rate ratios 1.04 [95% CI 1.04-1.05], 1.08 [95% CI 1.07-1.08], 1.07 [95% CI 1.06-1.07], and 1.05 [95% CI 1.04-1.05], respectively) over each 6-monthly band. In the DAA era, decompensated cirrhosis diagnosis and liver-related mortality numbers declined (incidence rate ratios 0.97 [95% CI 0.95-0.99] and 0.96 [95% CI 0.94-0.98], respectively), and HCC diagnosis and all-cause mortality numbers plateaued (incidence rate ratio 1.00 [95% CI 0.97-1.03] and 1.01 [95% CI 1.00-1.02], respectively) over each 6-monthly band. In the DAA era, alcohol-use disorder (AUD) was common in patients diagnosed with decompensated cirrhosis and HCC (65% and 46% had a history of AUD, respectively). AUD was independently associated with liver-related mortality (incidence rate ratio 3.35; 95% CI 3.14-3.58). CONCLUSIONS: In the DAA era, there has been a sharp decline in liver disease morbidity and mortality in New South Wales, Australia. AUD remains a major contributor to HCV-related liver disease burden, highlighting the need to address comorbidities. LAY SUMMARY: Rising hepatitis C-related morbidity and mortality is a major public health issue. However, development of highly effective medicines against hepatitis C (called direct-acting antivirals or DAAs) means hepatitis C could be eliminated as a public health threat by 2030. This study shows a sharp decline in liver disease morbidity and mortality since the introduction of DAAs in New South Wales, Australia. Despite this, heavy alcohol use remains an important risk factor for liver disease among people with hepatitis C. To ensure that the benefits of new antiviral treatments are not compromised, management of major comorbidities, including heavy alcohol use must improve among people with hepatitis C.

Expanded HIV pre-exposure prophylaxis (PrEP) implementation in communities in New South Wales, Australia (EPIC-NSW): design of an open label, single arm implementation trial.

BACKGROUND: The New South Wales (NSW) HIV Strategy 2016-2020 aims for the virtual elimination of HIV transmission in NSW, Australia, by 2020. Despite high and increasing levels of HIV testing and treatment since 2012, the annual number of HIV diagnoses in NSW has remained generally unchanged. Pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV infection among gay and bisexual men (GBM) when taken appropriately. However, there have been no population-level studies that evaluate the impact of rapid PrEP scale-up in high-risk GBM. Expanded PrEP Implementation in Communities in NSW (EPIC-NSW) is a population-level evaluation of the rapid, targeted roll-out of PrEP to high-risk individuals. METHODS: EPIC-NSW, is an open-label, single-arm, multi-centre prospective observational study of PrEP implementation and impact. Over 20 public and private clinics across urban and regional areas in NSW have participated in the rapid roll-out of PrEP, supported by strong community mobilization and PrEP promotion. The study began on 1 March 2016, aiming to enroll at least 3700 HIV negative people at high risk of HIV. This estimate took into consideration criteria for PrEP prescription in people at high risk for acquiring HIV as defined in the NSW PrEP guidelines. Study participants receive once daily co-formulated tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) and are followed for up to 24 months. Follow-up includes: testing for HIV at 1 month, HIV and other sexually transmissible infections three-monthly, HCV annually and monitoring of renal function six-monthly. Optional online behavioural surveys are conducted quarterly. The co-primary endpoints are (i) HIV diagnoses and incidence in the cohort and (ii) HIV diagnoses in NSW. DISCUSSION: EPIC-NSW is a population-based PrEP implementation trial which targets the entire estimated population of GBM at high risk for HIV infection in NSW. It will provide a unique opportunity to evaluate the population impact of PrEP on a concentrated HIV epidemic. TRIAL REGISTRATION: https://clinicaltrials.gov/ (identifying number NCT02870790 ; registration date 14 August 2016), pre-results stage.

Correction: expanded HIV pre-exposure prophylaxis (PrEP) implementation in communities in new South Wales, Australia (EPIC-NSW): design of an open label, single arm implementation trial.

After publication of the article [1], it has been brought to our attention that one of the members of the EPIC-NSW study group has had their name spelt incorrectly in the acknowledgements. The article mentions "Muhammad Hammoud" when in fact the correct spelling is "Mohamed Hammoud".

Changing pattern of sexually transmissible infections and HIV diagnosed in public sexual health services compared with other locations in New South Wales, 2010-14.

Background In Australia, testing and treatment for HIV and other sexually transmissible infections (STIs) is usually managed in general practice, while publicly funded sexual health clinics (PFSHC) attract people at higher risk for infection. The proportion of HIV and STI diagnoses in New South Wales (NSW) occurring in PFSHC stratified by priority population was investigated. METHODS: From 2010 to 2014, NSW notification frequencies for chlamydia, gonorrhoea, infectious syphilis, and HIV were compared with the number of diagnoses in PFSHC. The annual proportion of diagnoses at PFSHC was calculated and Wilcoxon rank-sum tests assessed trends. Diagnoses from PFSHC were also organised by priority population, including gay and bisexual men (GBM), people living with HIV, Aboriginal and Torres Strait Islander people, people who use injecting drugs, sex workers and young people. RESULTS: The annual proportion of HIV and STIs diagnosed at PFSHC increased (all P<0.001): chlamydia from 12% to 15%, gonorrhoea 23% to 38%, infectious syphilis 21% to 40% and HIV 22% to 30%. Overall, the majority of all infections diagnosed at PFSHC were among GBM, with the proportional distribution of chlamydia increasing from 32% to 46% among GBM (P<0.001) and decreasing among young people (50% to 40%; P<0.001). There were no other significant changes by population or infection at PFSHC. CONCLUSIONS: Increasing proportions of STI and HIV are being diagnosed at NSW PFSHC, mostly among GBM. PFSHC reorientation to priority populations continues to make a large and increasing contribution to STI and HIV control efforts in NSW.

Acellular pertussis vaccine effectiveness for children during the 2009-2010 pertussis epidemic in Queensland.

UNLABELLED: OBJECTIVES To assess the effectiveness of three, four and five doses of acellular pertussis vaccine against pertussis notification for children aged 1 - < 4 years and 5 - < 12 years, and the effectiveness of three doses of acellular pertussis vaccine against pertussis hospitalisation for children aged 1 - < 4 years. DESIGN, SETTING AND PARTICIPANTS: A population-based retrospective study of children aged 1 - < 12 years residing in Queensland, Australia, during 2009 and 2010. Routinely collected notification, hospitalisation, testing and vaccination data were used to describe notification rates and testing patterns and to assess vaccine effectiveness (VE) by the screening method. MAIN OUTCOME MEASURES: VE against pertussis notification for children aged 1 - < 4 years and 5 - < 12 years, by birth year, and VE against pertussis hospitalisation for children aged 1 - < 4 years. RESULTS: 1961 notifications and 29 hospitalisations were included in the VE calculations. VE point estimates against pertussis notification and hospitalisation in children aged 1 - < 4 years were similar in 2009 and 2010, and ranged between 83.5% and 89.4%. VE point estimates against notification among children aged 5 - < 12 years were between 71.2% and 87.7% in 2009, and between 34.7% and 70.3% in 2010. The numbers of pertussis tests performed for children, particularly polymerase chain reaction (PCR) tests, increased between 2009 and 2010. CONCLUSIONS: Acellular pertussis vaccine provided good protection within the first years of priming, but this waned as age increased. Changes in pertussis testing behaviour, because of increases in PCR use and awareness, may have contributed to increased pertussis notification rates and lower estimates of VE against notification owing to identification of milder disease.

The value of universal screening for COVID-19 cases on cruise ships during outbreaks.

OBJECTIVES: To describe the impact of universal screening for coronavirus disease 2019 (COVID-19) on passengers on cruise ships docking in Sydney, Australia, during 2022 that experienced a significant outbreak of COVID-19. Type of program or service: Cruise ship disease surveillance Methods: Case series, based on analysis of cruise ship voyages where universal screening of passengers was requested by a NSW health authority and undertaken by the cruise ship. RESULTS: Of 111 voyages in 2022, three fit the definition for this study. Universal screening during these voyages resulted in the detection of up to 1.8 times the number of existing COVID-19 cases, increasing attack rates of the three voyages from 14% to 24%; 13% to 28%; and 3% to 8% respectively. Case demographics showed an even gender distribution, with a majority 70 years or older. Asymptomatic case percentage ranged from 2% to 54%, with age and gender not associated with symptomatic status. Almost all cases were reported as being fully vaccinated. Genomic testing of cases showed multiple lineages of COVID-19 circulating in all three voyages. LESSONS LEARNT: Public health authorities, the cruise industry and passengers should be aware that a large number of unidentified cases of COVID-19 may disembark from a cruise ship that has experienced a large outbreak of the virus. These cases can seed the infection into vulnerable communities. Universal screening as part of the response to a significant outbreak will help identify cases and limit the spread of COVID-19.

Emergent Omicron BR.2.1 sublineage of SARS-CoV-2 in New South Wales, Australia: a subvariant with high fitness but without increased disease severity.

OBJECTIVES: To describe the epidemiology and impact of Omicron BR.2.1, an emergent SARS-CoV-2 Omicron BA.2.75 sublineage displaying high fitness compared to other cocirculating subvariants in New South Wales, Australia. METHODS: From September 01 to November 26, 2022, 4971 SARS-CoV-2 consensus genomes from unique patients were generated, and correlated with international travel and reinfection history, and admission to the intensive care unit. RESULTS: BR.2.1 became the predominant variant by late November, and was responsible for a significantly higher proportion of community-acquired cases during the study period (55.1% vs 38.4%, P < 0.001). Reinfections (defined as occurring between 6 and 24 weeks after a prior diagnosis of COVID-19) were significantly higher among BR.2.1 compared to non-BR.2.1 infected persons (17.0% vs 6.0%, P < 0.001). BR.2.1 cases were also significantly younger compared to non-BR.2.1 (median age 48 years (interquartile range [IQR] 32) vs 53 years (IQR 32), P = 0.004). The proportion of patients admitted to the intensive care unit with BR.2.1 was not significantly higher than other subvariants (2.3% vs 2.0%, P = 0.717). CONCLUSION: Having emerged locally within New South Wales, BR.2.1 caused a significant number of SARS-CoV-2 reinfections, but with disease severity comparable with other currently circulating lineages. Given its rapid rise in prevalence, BR.2.1 has the potential to become established internationally.

Outcomes from the first 2 years of the Australian National Hand Hygiene Initiative.

OBJECTIVE: To report outcomes from the first 2 years of the National Hand Hygiene Initiative (NHHI), a hand hygiene (HH) culture-change program implemented in all Australian hospitals to improve health care workers' HH compliance, increase use of alcohol-based hand rub and reduce the risk of health care-associated infections. DESIGN AND SETTING: The HH program was based on the World Health Organization 5 Moments for Hand Hygiene program, and included standardised educational materials and a regular audit system of HH compliance. The NHHI was implemented in January 2009. MAIN OUTCOME MEASURES: HH compliance and Staphylococcus aureus bacteraemia (SAB) incidence rates 2 years after NHHI implementation. RESULTS: In late 2010, the overall national HH compliance rate in 521 hospitals was 68.3% (168,641/246,931 moments), but HH compliance before patient contact was 10%-15% lower than after patient contact. Among sites new to the 5 Moments audit tool, HH compliance improved from 43.6% (6431/14,740) at baseline to 67.8% (106,851/157,708) (P < 0.001). HH compliance was highest among nursing staff (73.6%; 116,851/158,732) and worst among medical staff (52.3%; 17,897/34,224) after 2 years. National incidence rates of methicillin-resistant SAB were stable for the 18 months before the NHHI (July 2007-2008; P = 0.366), but declined after implementation (2009-2010; P = 0.008). Annual national rates of hospital-onset SAB per 10,000 patient-days were 1.004 and 0.995 in 2009 and 2010, respectively, of which about 75% were due to methicillin-susceptible S. aureus. CONCLUSIONS: The NHHI was associated with widespread sustained improvements in HH compliance among Australian health care workers. Although specific linking of SAB rate changes to the NHHI was not possible, further declines in national SAB rates are expected.

Adherence to daily HIV pre-exposure prophylaxis in a large-scale implementation study in New South Wales, Australia.

OBJECTIVES: To examine patterns of long-term pre-exposure prophylaxis (PrEP) adherence and its association with HIV seroconversion in NSW, Australia. DESIGN: Population-based HIV PrEP implementation study. METHODS: Expanded PrEP Implementation in Communities in New South Wales was an open-label study of daily oral PrEP which recruited participants from March 2016 to April 2018. Adherence was measured using dispensing records. PrEP discontinuation was defined as an at least 120-day period without PrEP coverage. Long-term adherence patterns were identified using group-based trajectory modelling. RESULTS: Participants dispensed at least once (n = 9586) were almost all male (98.5%), identified as gay (91.3%), with a median age of 34 years (range: 18-86). Of the 6460 (67.4%) participants who had at least 9 months of follow-up since first dispensing, 1942 (30.1%) discontinued. Among these, 292 (15.0%) restarted later. Four distinct groups were identified ['Steep decline' in adherence (15.8%), 'Steady decline' (11.6%), 'Good adherence' (37.4%), and 'Excellent adherence' (35.2%)]. Older (P < 0.001) and gay-identified (P < 0.001) participants were more likely to have higher adherence, so were those living in postcodes with a higher proportion of gay-identified male residents (P < 0.001). Conversely, those who at baseline reported recent crystal methamphetamine use and had a recent diagnosis of sexually transmitted infection (STI) had lower adherence (P < 0.001). Overall HIV incidence was 0.94 per 1000 person-years (95% confidence interval: 0.49-1.81; n = 9) and was highest in the 'steep decline' group (5.45 per 1000 person-years; P = 0.001). CONCLUSION: : About 15% of participants stopped PrEP during study follow-up and were at increased risk of HIV infection. They were more likely to be younger and report a recent STI or methamphetamine use prior to PrEP initiation.

Subtype-specific differences in transmission cluster dynamics of HIV-1 B and CRF01_AE in New South Wales, Australia.

INTRODUCTION: The human immunodeficiency virus 1 (HIV-1) pandemic is characterized by numerous distinct sub-epidemics (clusters) that continually fuel local transmission. The aims of this study were to identify active growing clusters, to understand which factors most influence the transmission dynamics, how these vary between different subtypes and how this information might contribute to effective public health responses. METHODS: We used HIV-1 genomic sequence data linked to demographic factors that accounted for approximately 70% of all new HIV-1 notifications in New South Wales (NSW). We assessed differences in transmission cluster dynamics between subtype B and circulating recombinant form 01_AE (CRF01_AE). Separate phylogenetic trees were estimated using 2919 subtype B and 473 CRF01_AE sequences sampled between 2004 and 2018 in combination with global sequence data and NSW-specific clades were classified as clusters, pairs or singletons. Significant differences in demographics between subtypes were assessed with Chi-Square statistics. RESULTS: We identified 104 subtype B and 11 CRF01_AE growing clusters containing a maximum of 29 and 11 sequences for subtype B and CRF01_AE respectively. We observed a > 2-fold increase in the number of NSW-specific CRF01_AE clades over time. Subtype B clusters were associated with individuals reporting men who have sex with men (MSM) as their transmission risk factor, being born in Australia, and being diagnosed during the early stage of infection (p < 0.01). CRF01_AE infections clusters were associated with infections among individuals diagnosed during the early stage of infection (p < 0.05) and CRF01_AE singletons were more likely to be from infections among individuals reporting heterosexual transmission (p < 0.05). We found six subtype B clusters with an above-average growth rate (>1.5 sequences / 6-months) and which consisted of a majority of infections among MSM. We also found four active growing CRF01_AE clusters containing only infections among MSM. Finally, we found 47 subtype B and seven CRF01_AE clusters that contained a large gap in time (>1 year) between infections and may be indicative of intermediate transmissions via undiagnosed individuals. CONCLUSIONS: The large number of active and growing clusters among MSM are the driving force of the ongoing epidemic in NSW for subtype B and CRF01_AE.

Long-term protection from HIV infection with oral HIV pre-exposure prophylaxis in gay and bisexual men: findings from the expanded and extended EPIC-NSW prospective implementation study.

BACKGROUND: Daily pre-exposure prophylaxis (PrEP) is effective in preventing HIV, but few long-term data are available on effectiveness and adherence in real-world settings. Here, we report trends in HIV incidence over 3 years in individuals at high risk who were prescribed PrEP in New South Wales (NSW), as well as adherence before the transition to subsidised PrEP. METHODS: Expanded PrEP Implementation in Communities-New South Wales (EPIC-NSW) was a pragmatic, prospective, single-arm, implementation study of daily, oral PrEP in 31 sites (sexual health clinics, general practices, and a hospital) in NSW, Australia. Eligible participants were HIV-negative adults (aged ≥18 years) who were at high risk of HIV infection as defined in local PrEP guidelines. Participants were prescribed coformulated (once-daily, oral tablet) tenofovir disoproxil fumarate (300 mg) and emtricitabine (200 mg) as HIV PrEP and were followed up with HIV testing, sexually transmitted infection testing, and PrEP dispensing. Originally planned for 3700 participants followed for 1 year, the study was expanded so that all eligible participants in the state could obtain PrEP and extended until publicly subsidised PrEP became available in Australia. The primary outcome was new HIV infection among all participants who were dispensed PrEP at least once and had at least one follow-up HIV test result. Adherence was estimated by medication possession ratio (MPR), defined as the proportion of PrEP pills dispensed in 90 days, assuming daily dosing. This study is registered with ClinicalTrials.gov, NCT02870790. FINDINGS: Between March 1, 2016, and April 30, 2018, we enrolled 9709 participants. 9596 participants were dispensed PrEP, of whom 9448 (98·3%) were gay or bisexual men. Participants were followed up until March 31, 2019, with at least one follow-up HIV test available in 9520 (99·2%) participants. Mean MPR declined from 0·93 to 0·64 from the first to the ninth quarter. There were 30 HIV seroconversions over 18 628 person-years, an incidence of 1·61 per 1000 person-years (95% CI 1·13-2·30). Being younger, living in a postcode with fewer gay men, reporting more risk behaviours at baseline, and having an MPR of less than 0·6 were each univariately associated with increased HIV incidence. In the final year of follow-up, when PrEP was mostly purchased rather than provided free by the study, HIV incidence remained low at 2·24 per 1000 person-years (1·46-3·44). INTERPRETATION: HIV incidence remained low over up to 3 years of follow-up, including during a transition from study-provided to publicly subsidised PrEP. In a setting of affordable PrEP and associated health-care services, very low HIV incidence of 1 to 2 per 1000 person-years can be maintained in gay and bisexual men who were previously at high risk. FUNDING: New South Wales Ministry of Health, Australian Capital Territory Health Directorate, Gilead Sciences.

Scientific evidence supporting recommendations on the use of the 9-valent HPV vaccine in a 2-dose vaccine schedule in Australia.

The Australian Technical Advisory Group on Immunisation (ATAGI) updated recommendations on the use of human papillomavirus (HPV) vaccines in the Australian Immunisation Handbook in 2018, regarding the use of the recently available 9-valent (9vHPV) vaccine, Gardasil 9, and a 2-dose schedule for young adolescents for HPV vaccines. This report provides an overview of the relevant scientific evidence that underpinned these updated recommendations. The 9vHPV vaccine includes 5 HPV types (HPV 31, 33, 45, 52 and 58) additional to the 4 that are also covered by the 4vHPV (Gardasil) vaccine (HPV 6,11,16,18). Accordingly, the 9vHPV vaccine is expected to prevent an additional 15% of cervical cancers and up to 20% of other HPV-related cancers. Non-inferior antibody responses after two 9vHPV vaccine doses given 6-12 months apart in girls and boys aged 9-14 years compared to women aged 16-26 years after three doses support the 2-dose schedule for adolescents of this age group. In clinical trials 9vHPV vaccine was well-tolerated with a similar safety profile to 4vHPV vaccine. The switch to 9vHPV vaccine and a 2-dose schedule is anticipated to improve public acceptability of the program and reduce HPV-related disease in the long-term.

Comparison of Trends in Rates of Sexually Transmitted Infections Before vs After Initiation of HIV Preexposure Prophylaxis Among Men Who Have Sex With Men.

Importance: There have been concerns that HIV preexposure prophylaxis (PrEP) may be associated with increases in sexually transmitted infections (STIs) because of subsequent reductions in condom use and/or increases in sexual partners. Objective: To determine trends in STI test positivity among high-risk men who have sex with men (MSM) before and after the start of HIV PrEP. Design, Setting, and Participants: A before-after analysis was conducted using a subcohort of a single-group PrEP implementation study cohort in New South Wales, Australia (Expanded PreEP Implementation in Communities in New South Wales [EPIC-NSW]), from up to 1 year before enrollment if after January 1, 2015, and up to 2 years after enrollment and before December 31, 2018. STI testing data were extracted from a network of 54 sexual health clinics and 6 primary health care clinics Australia-wide, using software to deidentify, encrypt, and anonymously link participants between clinics. A cohort of MSM dispensed PrEP for the first time during the study, with 2 or more STI tests in the prior year and who tested during follow-up, were included from the EPIC-NSW cohort of HIV-negative participants with high-risk sexual behavior. Data analysis was performed from June to December 2019. Exposures: Participants were dispensed coformulated tenofovir disoproxil fumarate (300 mg) and emtricitabine (200 mg) as HIV PrEP. Main Outcomes and Measures: The main outcome was STI, measured using test positivity, defined as the proportion of participants testing positive for an STI at least once per quarter of follow-up. Outcomes were calculated for Chlamydia trachomatis and Neisseria gonorrhoea by site of infection (anorectal, pharyngeal, urethral, or any) and for syphilis. Results: Of the EPIC-NSW cohort of 9709 MSM, 2404 were included in the before-after analysis. The mean (SD) age of the participants was 36 (10.4) years, and 1192 (50%) were Australia-born. STI positivity was 52% in the year after PrEP (23.3% per quarter; 95% CI, 22.5%-24.2% per quarter) with no significant trend (mean rate ratio [RR] increase of 1.01 per quarter [95% CI, 0.99-1.02]; P = .29), compared with 50% positivity in the year prior to PrEP (20.0% per quarter [95% CI, 19.04%-20.95% per quarter]; RR for overall STI positivity, 1.17 [95% CI, 1.10-1.24]; P < .001), with an increase in quarterly STI positivity (mean RR of 1.08 per quarter, or an 8% increase per quarter [95% CI, 1.05-1.11]; P < .001; RR, 0.93 [95% CI, 0.90-0.96]; P < .001). Findings were similar when stratified by specific STIs and anatomical site. Conclusions and Relevance: STI rates were high but stable among high-risk MSM while taking PrEP, compared with a high but increasing trend in STI positivity before commencing PrEP. These findings suggest the importance of considering trends in STIs when describing how PrEP use may be associated with STI incidence.

Increased HIV Subtype Diversity Reflecting Demographic Changes in the HIV Epidemic in New South Wales, Australia.

Changes over time in HIV-1 subtype diversity within a population reflect changes in factors influencing the development of local epidemics. Here we report on the genetic diversity of 2364 reverse transcriptase sequences from people living with HIV-1 in New South Wales (NSW) notified between 2004 and 2018. These data represent >70% of all new HIV-1 notifications in the state over this period. Phylogenetic analysis was performed to identify subtype-specific transmission clusters. Subtype B and non-B infections differed across all demographics analysed (p < 0.001). We found a strong positive association for infections among females, individuals not born in Australia or reporting heterosexual transmission being of non-B origin. Further, we found an overall increase in non-B infections among men who have sex with men from 50 to 79% in the last 10 years. However, we also found differences between non-B subtypes; heterosexual transmission was positively associated with subtype C only. In addition, the majority of subtype B infections were associated with clusters, while the majority of non-B infections were singletons. However, we found seven non-B clusters (≥5 sequences) indicative of local ongoing transmission. In conclusion, we present how the HIV-1 epidemic has changed over time in NSW, becoming more heterogeneous with distinct subtype-specific demographic associations.

Epidemiology of lymphogranuloma venereum in New South Wales, 2006-2015.

AIM: To describe the epidemiology of lymphogranuloma venereum (LGV) in New South Wales (NSW) from 2006 to 2015. METHODS: LGV notification data between 2006 and 2015 from New South Wales were analysed to describe time trends in counts and rates by gender, age group and area of residence, as well as anatomical sites of infection. A positivity ratio was calculated using the number of LGV notifications per 100 anorectal chlamydia notifications per year. Data linkage was used to ascertain the proportion of LGV cases that were co-infected with HIV. RESULTS: There were 208 notifications of LGV in NSW from 2006 to 2015; all were among men, with a median age of 42 years, and half were residents of inner-city Sydney. Annual notifications peaked at 57 (1.6 per 100,000 males) in 2010, declined to 16 (0.4 per 100,000 males) in 2014, and then increased to 34 (0.9 per 100,000 males) in 2015. Just under half (47.4%) of LGV cases were determined to be co-infected with HIV. CONCLUSION: The number of LGV notifications each year has not returned to the low levels seen prior to the peak in 2010. Continued public health surveillance is important for the management and control of LGV.

Limited Sustained Local Transmission of HIV-1 CRF01_AE in New South Wales, Australia.

Australia's response to the human immunodeficiency virus type 1 (HIV-1) pandemic led to effective control of HIV transmission and one of the world's lowest HIV incidence rates-0.14%. Although there has been a recent decline in new HIV diagnoses in New South Wales (NSW), the most populous state in Australia, there has been a concomitant increase with non-B subtype infections, particularly for the HIV-1 circulating recombinant form CRF01_AE. This aforementioned CRF01_AE sampled in NSW, were combined with those sampled globally to identify NSW-specific viral clades. The population growth of these clades was assessed in two-year period intervals from 2009 to 2017. Overall, 109 NSW-specific clades were identified, most comprising pairs of sequences; however, five large clades comprising ≥10 sequences were also found. Forty-four clades grew over time with one or two sequences added to each in different two-year periods. Importantly, while 10 of these clades have seemingly discontinued, the remaining 34 were still active in 2016/2017. Seven such clades each comprised ≥10 sequences, and are representative of individual sub-epidemics in NSW. Thus, although the majority of new CRF01_AE infections were associated with small clades that rarely establish ongoing chains of local transmission, individual sub-epidemics are present and should be closely monitored.

Establishment of a surveillance system (utilising Midwifes Data Collection Systems) for monitoring the impact of hepatitis B vaccination on the population prevalence of chronic hepatitis B virus infection in Australia.

OBJECTIVE: To examine how routine hepatitis B surface antigen (HBsAg) testing of antenatal women (as identified on the NT Midwifes Data Collection System) can be used to track the impact of hepatitis B (HBV) vaccination on the prevalence of chronic HBV infection in the Northern Territory (NT). METHODS: Women who gave birth between 01 July 2002 and 30 June 2004 were identified from the NT Midwives Data Collection System (MDCS). For each woman, the unique hospital record number (HRN) was linked to the information system of the NT Government pathology service to obtain the results of serological tests for hepatitis B. The prevalence of HBsAg was calculated by age, Indigenous status, and maternal country of birth. RESULTS: During the study period, 1061 records of women from the NT MDCS could be linked to HBsAg results. Overall, 33 (3.1%) were positive for HBsAg, of whom 29 were recorded as Indigenous and the remaining four were born outside Australia. CONCLUSIONS: Linking data from the NT MDCS and HBsAg results from government pathology service is a feasible means to monitor the impact of HBV vaccination policy. IMPLICATIONS: Routine inclusion of HBsAg results in all state and territory midwives data collections should be pursued.