Suchergebnisse

IntroductionStudies in heterosexual HIV serodiscordant couples have provided critical evidence on the role of HIV treatments in reducing HIV transmission risk. However, there are limited data regarding the effect of treatment on HIV transmission in homosexual male couples. We examined features of male homosexual HIV serodiscordant relationships that may impact upon the design of HIV treatment and transmission studies.MethodsData were from a prospective cohort study of HIV‐negative homosexual men in Sydney, Australia. Men were followed up with six‐monthly interviews and annual testing for HIV. Characteristics of men in HIV serodiscordant and seroconcordant relationships at baseline were compared, and a longitudinal analysis performed of rate of relationship break‐up and of HIV incidence.ResultsAt baseline, 5.5% of participants (n=79) had an HIV‐positive partner. Most (80.8%) of these relationships were non‐monogamous, and 36.7% of men reported recent unprotected anal intercourse (UAI) with casual partners. The rate of relationship break‐up was 29.5 per 100 person‐years. Half of men in serodiscordant relationships (49.4%) reported recent UAI with their regular partners. HIV incidence was 2.2 per 100 person‐years. It was substantially higher in relationships of less than one year's duration (6.1 per 100 person‐years) and in men who reported unprotected receptive anal intercourse with ejaculation with their regular partners (15.5 per 100 person‐years).ConclusionsLevels of HIV transmission risk and incidence were high, particularly in early relationships. Rates of relationship break‐up were high. These data suggest that studies of HIV treatments and transmission in homosexual serodiscordant couples should focus on early relationships so as not to underestimate risk, and sample sizes must allow for high rates of relationship break‐up.

AbstractIntroduction:Overseas‐born gay and bisexual men (GBM) are overrepresented in HIV diagnoses in Australia. We assessed social and sexual behaviours, and the use of HIV prevention and testing, by region of birth and length of residence in Australia. We sought to identify similarities and differences between recently arrived and non‐recently arrived GBM from non‐English‐speaking countries to improve targeting and engagement with HIV testing and prevention.Methods:Data were collected in national repeated, behavioural surveillance surveys conducted across Australia during 2019–2021. Logistic regression was used to identify factors that differentiated between recently arrived (<2 years) and non‐recently arrived (≥2 years in Australia) GBM from non‐English‐speaking countries.ResultsAmong 24,707 participants in 2019–21, 2811 (11.4%) were from high‐income English‐speaking countries, 714 (2.9%) were recently arrived overseas‐born GBM and 3833 (15.5%) were non‐recently arrived migrants. Recently arrived GBM were most likely to be born in Asia (36.1%) and Europe (21.1%). Compared with non‐recently arrived GBM, recently arrived GBM from non‐English‐speaking countries were younger (aOR = 0.95, 95% CI = 0.94–0.96, p<0.001), more likely to be students (aOR = 1.43, 95% CI = 1.11–1.85, p = 0.005), less likely to be in full‐time employment (aOR = 0.56, 95% CI = 0.46–0.69, p <0.001), more likely to report consistent condom use (aOR = 1.30, 95% CI = 1.01–1.66, p = 0.039), but had lower awareness (aOR = 0.62, 95% CI = 0.48–0.80, p<0.001) and use of pre‐exposure prophylaxis (PrEP) (22.8%, vs. 32.3%, χ2(1, 4185) = 23.78, p<0.001), and similar levels of casual sex with a risk of HIV acquisition or transmission (aOR = 1.29, 95% CI = 0.98–1.69, p = 0.066). Recently arrived GBM reported similar levels of lifetime HIV testing (aOR = 0.97, 95% CI = 0.54–1.74, p = 0.915) and recent HIV testing (OR = 1.03, 95% CI = 0.86–1.22, p = 0.779), but were much less likely to have tested at general practitioners (aOR = 0.53, 95% CI = 0.41–0.68, p<0.001) and more likely to report testing at hospitals (aOR = 3.35, 95% CI = 2.53–4.43, p<0.001), at home (aOR = 2.85, 95% CI = 1.63–4.99, p<0.001), or community‐based services (aOR = 1.36, 95% CI = 1.01–1.84, p = 0.043).ConclusionsRecently arrived GBM from non‐English‐speaking countries reported similar levels of risk of HIV acquisition to longer‐term residents in Australia, but lower levels of PrEP awareness and use, and more reliance on HIV testing services which are free or low cost. It is necessary to enhance access to HIV testing and prevention among recently arrived GBM in Australia.

AbstractIntroductionHIV pre‐exposure prophylaxis (PrEP) has been government subsidized in Australia since April 2018 and while uptake is high among men who have sex with men, rates of discontinuation are also high. The aims of this study were to examine the impact of discontinuation on overall PrEP usage, the proportion of PrEP users who discontinue and the predictors of discontinuation.MethodsWe used linked de‐identified dispensing records of all government subsidized PrEP in Australia between April 2018 and September 2021: a whole‐of‐population data set. Defining discontinuation as 180 days or more without PrEP after the final dispensed supply, we calculated the number of people who discontinued at each 6‐month interval during the study period, the proportion who had discontinued 2 years after the first supply and, using Cox regression, predictors of discontinuation.ResultsOf 49,164 people dispensed PrEP (98.5% male, median age 34 years), 40.3% (19,815) had discontinued by September 2021. Within 2 years of their first supply, 11,150 (37.7%) of 29,549 PrEP users had discontinued, including 10.0% after a single dispensed supply. Large variations were observed, particularly according to prescriber characteristics: discontinuation was higher among people prescribed PrEP by low caseload (≤10 patients) prescribers (61.2%) than by high caseload (>100 patients) prescribers (31.1%, p<0.001), and by prescribers practising in areas with low estimated prevalence (<1.0%) of gay men (64.1%) than high (>5%) prevalence (36.7%, p<0.001). Women and younger people were more likely to discontinue, while patients receiving a higher level of government subsidy were less likely. The independent predictors of discontinuation with the greatest effect size were female sex (adjusted hazards ratio [aHR] 2.99, p<0.001), low estimated gay prevalence of prescriber location (aHR 1.98, p<0.001) and low prescriber PrEP caseload (aHR 1.79, p<0.001).ConclusionsThere are high rates of PrEP discontinuation in Australia and some populations are at increased risk of discontinuation. Strategies are needed to support persistence on PrEP and the re‐starting of PrEP during periods of risk.

AbstractIntroductionHIV pre‐exposure prophylaxis (PrEP) has been publicly available since 2018 in Australia as a daily regimen. In 2019, clinical guidelines were updated to support guidance on event‐driven PrEP (ED‐PrEP) use. We assessed trends in the PrEP dosing regimen by comparing daily PrEP use to ED‐PrEP among cisgender gay, bisexual and other men who have sex with men (GBMSM).MethodsData from repeated, cross‐sectional, national behavioural surveillance surveys were analysed from 2019 to 2023 among participants not living with HIV. Logistic regression models were conducted to assess trends and compared ED‐PrEP users to non‐PrEP users and daily PrEP.ResultsAmong 38,880 participants, overall PrEP use with any regimen increased from 27.6% in 2019 to 42.7% in 2023 (OR = 1.16, 95% CI = 1.15−1.18, p < 0.001). Among 12,922 participants who reported PrEP use in the last 6 months, the proportion reporting ED‐PrEP use increased from 7.6% in 2019 to 27.8% in 2023 (OR = 1.41, 95% CI = 1.37−1.46, p < 0.001) with those who reported daily PrEP decreasing from 92.4% to 63.3% (OR = 0.64, 95% CI = 0.62−0.66, p < 0.001). In a cross‐sectional sub‐sample in 2022–2023 (n = 8840), compared to ED‐PrEP users, non‐PrEP users were less likely to have received three or more HIV tests in the last 12 months (aRRR = 0.26, 95% CI = 0.22−0.31, p < 0.001), have 2−10 male sexual partners in the last 6 months (aRRR = 0.24, 95% CI = 0.14−0.41, p < 0.001) or 11 or more (aRRR = 0.26, 95% CI = 0.15−0.45, p < 0.001) compared to none, or to report condomless anal intercourse with casual partners (aRRR = 0.38, 95% CI = 0.32−0.46, p < 0.001). Compared to ED‐PrEP users, daily PrEP users were more likely to have received three of more HIV tests in the last year (aRRR = 3.73, 95% CI = 3.15−4.40, p < 0.001) and less likely to be born overseas and lived in Australia for less than 5 years compared to being born in Australia (aRRR = 0.64, 95% CI = 0.49−0.83, p = 0.001).ConclusionsWhile daily PrEP remains the most common PrEP dosing regimen among GBMSM in Australia, there has been a steep increase in the proportion of PrEP users who are taking ED‐PrEP. Monitoring of PrEP use should continue to adapt to new dosing methods and future PrEP options. As ED‐PrEP use increases, further work is needed to ensure those taking ED‐PrEP are taking it effectively to prevent HIV.

AbstractIntroductionDue to a lack of robust population denominators, Australia is unable to accurately monitor changes in the HIV epidemic for some populations. The ratio of HIV transmission relative to the number of people with HIV (an incidence prevalence ratio, or IPR) can measure such changes. The IPR is measured against an IPR benchmark derived from post‐HIV acquisition life expectancy, to indicate whether an HIV epidemic is shrinking or growing. Using IPRs and Australia‐specific IPR benchmarks, this study aims to describe the Australian HIV epidemic among three groups: men with HIV attributed to male‐to‐male sex, women with HIV and people with HIV attributed to injection drug use.MethodsUsing mathematical modelling derived from HIV notifications, cohort and administrative data, IPRs were generated for each of the three groups. These IPRs were compared with IPR benchmarks derived from post‐HIV acquisition mortality estimates using abridged life tables for men, women and people who inject drugs. The IPR benchmark for men was applied to people with HIV attributed to male‐to‐male sex. Trends in the IPR over time were described for each reported population from 2015 to 2022.ResultsOverall, the IPR fell by 80%, from 0.040 (range: 0.034−0.045) in 2015 to 0.008 (range: 0.003−0.013) in 2022 and fell below the benchmark (0.022) in 2020. Among people with HIV attributed to male‐to‐male sex, the IPR fell by 85%, from 0.041 (range: 0.034−0.047) in 2015 to 0.006 (range: 0.003−0.024) in 2022 and fell below the benchmark (0.022) in 2020. Among women with HIV, the IPR fell by 56%, from 0.032 (range: 0.026−0.039) in 2015 to 0.014 (range: 0.003−0.029) in 2022 and fell below the benchmark (0.022) in 2019. Among people with HIV attributed to injection drug use, the IPR fell by 61%, from 0.036 (range: 0.022−0.047) in 2015 to 0.014 (range: 0.002−0.057) in 2022 and fell below the benchmark (0.028) in 2019.ConclusionsAustralian IPRs in all populations examined have dropped below the level required to sustain the HIV epidemic at current levels. By applying this method in other contexts, the changing scale of HIV epidemics may be better described for populations lacking robust population denominators.

AbstractIntroductionThere are few data about the range of strategies used to prevent sexual HIV transmission within gay male serodiscordant couples. We examined HIV prevention strategies used by such couples and compared differences between countries.MethodsOpposites Attract was a cohort study of male serodiscordant couples in Australia, Brazil and Thailand, from May 2014 (Australia) or May 2016 (Brazil/Thailand) to December 2016. At visits, HIV‐positive partners had viral load (VL) tested; HIV‐negative partners reported sexual behaviour and perceptions of their HIV‐positive partner's VL results. Within‐couple acts of condomless anal intercourse (CLAI) were categorized by strategy: condom‐protected, biomedically protected (undetectable VL and/or pre‐exposure prophylaxis [PrEP]), or not protected by either (HIV‐negative partners engaging in insertive CLAI, receptive CLAI with withdrawal, or receptive CLAI with ejaculation).ResultsA total of 343 couples were included in this analysis (153 in Australia, 93 in Brazil and 97 in Thailand). Three‐quarters of HIV‐positive partners were consistently virally suppressed (<200 copies/mL) during follow‐up, and HIV‐negative partners had correct perceptions of their partner's VL result for 76.5% of tests. One‐third of HIV‐negative partners used daily PrEP during follow‐up. Over follow‐up, 73.8% of couples had CLAI. HIV‐negative partners reported 31,532 acts of anal intercourse with their HIV‐positive partner. Of these, 46.7% were protected by condoms, 48.6% by a biomedical strategy and 4.7% of acts were not protected by these strategies. Australian couples had fewer condom‐protected acts and a higher proportion of biomedically protected acts than Brazilian and Thai couples. Of the 1473 CLAI acts where the perceived VL was detectable/unknown and were not protected by PrEP (4.7% of all acts), two‐thirds (n = 983) were when the HIV‐negative partner was insertive (strategic positioning). Of the 490 acts when the HIV‐negative partner was receptive, 261 involved withdrawal and 280 involved ejaculation. Thus, <1% of acts were in the highest risk category of receptive CLAI with ejaculation.ConclusionsCouples used condoms, PrEP or perceived undetectable VL for prevention in the majority of anal intercourse acts. Only a very small proportion of events were not protected by these strategies. Variation between countries may reflect differences in access to HIV treatment, education, knowledge and attitudes.

AbstractIntroductionThere are no longitudinal HIV incidence data among men who have sex with men (MSM) and transgender women (TGW) in Indonesia. We aimed to estimate HIV prevalence and incidence and identify associated factors among clinic attendees in Jakarta and Bali.MethodsWe conducted a retrospective cohort study using medical records from five clinics. We reviewed HIV tests among MSM/TGW aged ≥18 years who attended the clinics between 1 January 2018 to 31 December 2020 in Jakarta and 1 January 2017 to 31 December 2019 in Bali. HIV prevalence was measured at the first test. Those with an HIV‐negative test and ≥1 follow‐up test/s were included in the person‐years (PY) at risk to determine HIV incidence. The PY at risk calculation started at the first negative test until the last recorded negative test or seroconversion. Multivariate Poisson regression was used to determine factors associated with HIV acquisition.ResultsAmong 5203 and 2815 individuals with an HIV test result in Jakarta and Bali, respectively, at the first HIV test, 1205 and 616 were HIV positive (HIV prevalence 23.2% and 21.9%). The longitudinal sample included 1418 and 873 individuals, respectively. The median number of tests among repeat testers was 3 in Jakarta (interquartile range [IQR] = 2–4) and 3 in Bali (IQR = 2–5). At baseline, about one‐quarter were aged <25 years, >90% were MSM and >35% had been tested for HIV previously. In Jakarta, there were 127 HIV seroconversions in 1353 PY (incidence 9.39/100 PY, 95% CI = 7.89–11.17), and in Bali, 71 seroconversions in 982 PY (incidence 7.24/100 PY, 95% CI = 5.73–9.13). Compared to those aged 18–24 years, the incidence rate was lower in older patients (Jakarta—30–39 years: aRR = 0.56, 95% CI = 0.34–0.92; 40+ years: aRR = 0.34, 95% CI = 0.14–0.81; Bali—25–29 years: aRR = 0.44, 95% CI = 0.25–0.79; 30–39 years: aRR = 0.33, 95% CI = 0.18–0.61; 40+ years: aRR = 0.06, 95% CI = 0.01–0.48). In Jakarta, incidence was lower in those with university education than in those without (aRR = 0.66, 95% CI = 0.45–0.96). In Bali, those who had been referred by outreach workers had a higher incidence than those who self‐presented for testing (aRR = 1.85, 95% CI = 1.12–3.07).ConclusionsWe observed very high HIV prevalence and incidence rate estimates. Measures to encourage regular testing and effective use of HIV prevention, including pre‐exposure prophylaxis scale‐up and demand creation, are needed.

AbstractIntroductionThe 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.MethodsWe 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.ResultsWe 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.ConclusionsThe 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.