Characteristics of Human Immunodeficiency Virus (HIV) Seroconversions in a Large Prospective Implementation Cohort Study of Oral HIV Preexposure Prophylaxis in Men Who Have Sex with Men (EPIC-NSW).

BACKGROUND: Most human immunodeficiency virus (HIV) seroconversions in people who have initiated preexposure prophylaxis (PrEP) occur in the context of insufficient adherence. We describe participants who seroconverted after being dispensed PrEP in a large PrEP implementation study in Australia. METHODS: Expanded PrEP Implementation in Communities in New South Wales was an implementation study of daily oral PrEP in individuals aged ≥18 years at high risk for acquiring HIV. HIV seroconversions were defined as a positive HIV test by either antigen, antibody, or detectable HIV viral load after enrollment. Insufficient adherence, measured by dispensing logs or participant self-report, was defined as <4 PrEP doses per week. RESULTS: A total of 9596 participants were enrolled and dispensed PrEP between 1 March 2016 and 30 April 2018; 30 were diagnosed with HIV by 31 March 2019. The median (interquartile range [IQR]) age was 31 (25-38) years, all identified as male, 29 (97%) identified as gay or homosexual, and 20 (69%) lived in a postcode with a low concentration of gay male residents. The median (IQR) days from first PrEP dispensing to diagnosis was 409 (347-656). There was no evidence that participants who seroconverted had been sufficiently adherent to PrEP. Nineteen (63%) participants who seroconverted were diagnosed with chlamydia, gonorrhoea, syphilis, or new hepatitis C infection. One participant had resistance to emtricitabine (M184V mutation) at diagnosis. CONCLUSIONS: Participants who seroconverted were insufficiently adherent to PrEP despite being at high risk for acquiring HIV. Understanding the reasons for poor PrEP adherence in individuals who subsequently acquire HIV is critical to improving PrEP effectiveness.

Factors Associated With Willingness to Use Daily Antibiotics as Sexually Transmitted Infection Prophylaxis Among HIV Preexposure Prophylaxis-Experienced Gay and Bisexual Men in Australia.

BACKGROUND: Gay and bisexual men (GBM) who use HIV preexposure prophylaxis (HIV-PrEP) have high rates of bacterial sexually transmitted infections (STIs). The use of daily antibiotics as STI preexposure prophylaxis (STI-PrEP) may be appealing to GBM who are using or have previously used HIV-PrEP (HIV-PrEP-experienced) for the prevention of bacterial STIs. METHODS: We examined willingness to use daily STI-PrEP among a cross-sectional sample of HIV-PrEP-experienced GBM in Australia who participated in an observational online cohort study from August 2018 to March 2020. Factors associated with willingness to use daily STI-PrEP were determined using bivariate and multivariate logistic regression. RESULTS: Of the 1347 participants, half (54.3%) were willing to use daily STI-PrEP. Factors independently associated with greater willingness to use daily STI-PrEP included having >10 sexual partners in the last 6 months, using methamphetamine in the last 6 months, being more conscious about avoiding STIs, having a greater number of STIs since commencing HIV-PrEP, being willing to take HIV-PrEP for as long as they were at risk of acquiring HIV, and only using condoms when a sexual partner requested them. Conversely, factors associated with less willingness to use daily STI-PrEP included being university educated, using nondaily dosing regimens of HIV-PrEP, preferring event-driven HIV-PrEP, and being concerned about long-term HIV-PrEP adverse effects. CONCLUSIONS: Sexually transmitted infection PrEP is likely to be appealing to many HIV-PrEP-experienced GBM, especially those who engage in activities associated with a higher risk of STI transmission. However, they are less likely to be willing to use STI-PrEP unless it aligns with their HIV-PrEP dosing regimen, suggesting that research into the safety and efficacy of alternative STI prophylaxis dosing options should be prioritized.

Attitudes Towards Treatment as Prevention Among PrEP-Experienced Gay and Bisexual Men in Australia.

The introduction of HIV pre-exposure prophylaxis (PrEP) has the potential to impact the attitudes gay and bisexual men (GBM) who consequently choose to take PrEP have towards treatment as prevention (TasP), and the extent to which they are willing to have condomless anal intercourse (CLAI) with an HIV-positive sexual partner who has an undetectable viral load (UVL). Using a cross-sectional sample from an observational cohort study conducted from August 2018 to March 2020, we examined the extent to which PrEP-experienced GBM are willing to have CLAI with a partner who has a UVL. Simple and multiple logistic regression models were used to identify associated variables. Of the 1386 participants included in the analyses, 79.0% believed in the effectiveness of TasP, and 55.3% were willing to have CLAI with a partner who has a UVL. Wiling participants were less worried about getting HIV when taking PrEP and more likely to believe in TasP. Further research is needed to better understand the gap between belief in TasP and willingness to have CLAI with a partner who has a UVL among PrEP-experienced GBM.

Low Prior Exposure and Incidence of Hepatitis C in Human Immunodeficiency Virus-Negative Gay and Bisexual Men Taking Preexposure Prophylaxis (PrEP): Findings From the Expanded PrEP Implementation in Communities-New South Wales Prospective Implementation Study.

BACKGROUND: The use of preexposure prophylaxis (PrEP) for the prevention of human immunodeficiency virus (HIV) has raised concerns of increased sexual risk behaviors. These behaviors may be associated with increased incidence of sexually acquired hepatitis C virus (HCV) among gay and bisexual men. METHODS: The Expanded PrEP Implementation in Communities-New South Wales (EPIC-NSW) study was a cohort study of daily coformulated tenofovir disoproxil fumarate and emtricitabine for HIV prevention. We recruited 9596 people at high risk of HIV acquisition from 31 clinics across New South Wales and the Australia Capital Territory in Australia. We report prior exposure to HCV and incidence in this cohort between 2016 and 2019. RESULTS: At least 1 HCV test result was available for 8658 (90.2%) participants. These individuals had a median age of 34 years (interquartile range, 28-43), most of whom were male (8530, 98.5%), identified as gay (7944, 91.8%), and were born in Australia (51.8%). Prior exposure to HCV was detected among 81 participants at baseline (0.9%; 95% confidence interval [CI]: .71.2). Twenty of 8577 participants were diagnosed with incident infection (rate 0.2/100 person-years [95% CI: .1-.3/100 person-years]). They were significantly older (median age 41 years vs 34 years, P = .044), and more likely to report methamphetamine use at baseline (incidence rate ratio, 2.7 [95% CI: 1.00-7.2]) than those without incident infection. CONCLUSIONS: In this population of PrEP users, HCV prior exposure and incidence were low. With high levels of HCV and HIV testing and treatment, the dual goals of HIV and HCV elimination could be achieved in this population. Clinical Trials Registration: number NCT02870790.

Predictors of Daily Adherence to HIV Pre-exposure Prophylaxis in Gay/Bisexual Men in the PRELUDE Demonstration Project.

Adequate adherence to pre-exposure prophylaxis (PrEP) is critical to prevent HIV infection, but accurately measuring adherence remains challenging. We compared two biological [blood drug concentrations in plasma and peripheral blood mononuclear cells (PBMC)] and two self-reported measures (facilitated recall to clinicians and self-report in online surveys) and identified predictors of daily PrEP adherence among gay and bisexual men (GBM) in their first 12 months on PRELUDE, an open-label, single-arm PrEP demonstration project in New South Wales, Australia. 327 participants were enrolled; 263 GBM attended their 12-month follow-up visit (81% retention). Overall, 91% of blood samples had plasma drug concentrations indicative of taking 7 pills/week, and 99% had protective drug concentrations (≥ 4 pills/week). Facilitated recall to clinicians identified 99% of participants with protective adherence as measured by PBMC drug concentrations. Daily adherence measured by facilitated recall was associated with behavioural practices including group sex (aOR 1.33, 95% CI 1.15-1.53, p < 0.001). Retained participants maintained high adherence to daily PrEP over 12 months, confirmed by four different measures. Facilitated recall to clinicians is a suitable measure for assessing PrEP adherence in populations engaged in care where there is established trust and rapport with patients. Trial registration: ClinicalTrials.gov NCT02206555.

High Adherence to HIV Pre-exposure Prophylaxis and No HIV Seroconversions Despite High Levels of Risk Behaviour and STIs: The Australian Demonstration Study PrELUDE.

PrELUDE study evaluated daily pre-exposure prophylaxis (PrEP) in high-risk individuals in Australia. This open-label, single-arm study tested participants for HIV/STI and collected behavioural information three-monthly. We report trends over 18 months in medication adherence, side-effects, HIV/STI incidence and behaviour. 320 gay/bisexual men (GBM), 4 women and 3 transgender participants, followed on average 461 days, reported taking seven pills/week on 1,591 (88.5%) occasions and 4-6 pills/week on 153 (8.5%) occasions. No HIV infections were observed. STI incidence was high and stable, while gonorrhoea infections declined from 100.0 to 25.8/100 person-years between 6 and 15 months (p < 0.001). The number of HIV-positive and unknown-status sex partners, and condomless anal intercourse, significantly increased. In this high-risk cohort of mainly GBM, increases in risk behaviours and high STI incidence were not accompanied by HIV infections due to high adherence to daily PrEP. The study informed policy and further PrEP implementation among Australian GBM.

The Role of Age and Homonegativity in Racial or Ethnic Partner Preferences Among Australian Gay and Bisexual Men.

We investigated the racial or ethnic partner preferences among Australian gay and bisexual men (GBM) as part of a large study of sexual preferences among GBM, to identify whether racial bias was a factor in how GBM expressed their partner preferences. We surveyed 1853 Australian GBM about their partner preferences and preferred sex practices. We used logistic regression to identify whether factors such as age, gay social engagement, or men's own ethnicity or race were associated with ethnic and racial partner preferences. Mean age was 34.8 years. Ethnic or racial background included: white or "Caucasian" (86.6%), Australian Aboriginal (2.7%), and Asian (6.6%). Mean attraction scores were highest for "Caucasian" men, and lowest for Aboriginal and Asian men. Under half (41.6%) were attracted to all racial or ethnic types; 7.7% were only attracted to "Caucasian" men. Being older and lower homonegativity scores were independently associated with finding all ethnic and racial types attractive. Being attracted only to "Caucasian" men was associated with younger age. Mental health was not associated with ethnic or racial partner preferences. Although men more commonly found most racial or ethnic types attractive, racial biases in partner selection were more evident among younger men, and among those who were less comfortable with their own sexuality. Addressing anti-gay stigma and broader exposure to gay community subcultures may be as important in countering racial bias.

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".

High-risk sexual behaviours among gay and bisexual men: comparing event-level casual sex encounters among seroconverters and non-seroconverters.

BACKGROUND: With increasing use of non-condom-based HIV risk reduction strategies by gay and bisexual men (GBM), we compared occasions of condomless anal intercourse with casual partners (CLAIC) that resulted in HIV transmission and similar occasions when HIV transmission did not occur. METHODS: We compared two demographically similar samples of Australian GBM. The HIV Seroconversion Study (SCS) was an online cross-sectional survey of GBM recently diagnosed with HIV. The Pleasure and Sexual Health (PASH) study was an online cross sectional survey of GBM generally. Using logistic regression, we compared accounts of CLAIC reported by men in SCS as being the event which led to them acquiring HIV, with recent CLAIC reported by HIV-negative men in PASH. RESULTS: In SCS, 85.1% of men reported receptive CLAIC, including 51.8% with ejaculation; 32.1% reported having previously met this partner and 28.6% believed this partner to be HIV-negative. Among HIV-negative men in PASH reporting recent CLAIC, 65.5% reported receptive CLAIC, including 29.9% with ejaculation; 59.3% reported having previously met this partner and 70.1% believed this partner to be HIV-negative. CONCLUSIONS: While both groups of men engaged in CLAIC, how they engaged in CLAIC differed, and the context in which they did so was different. A generic measure of CLAIC conceals the critical elements of HIV risk, particularly the role of receptive CLAIC, among GBM that distinguish those who seroconverted and those who did not. Detailed information about the context and nature of the practise of CLAIC is required for a more complete understanding of HIV risk among GBM.

Preexposure Prophylaxis of HIV Infection: the Role of Clinical Practices in Ending the HIV Epidemic.

PURPOSE OF REVIEW: The aim of this study is to summarise the recent evidence from high-income settings about providers' ability to deliver on the UNAIDS goal of at least three million people at substantial risk of HIV infection with PrEP by 2020, including awareness and knowledge about PrEP, willingness to prescribe PrEP, current levels of prescribing and service delivery models and issues. RECENT FINDINGS: Awareness about PrEP among health providers is growing, but at different pace depending on provider type. HIV and sexual health specialists are more likely to have knowledge about PrEP than generalists, and to be willing to prescribe it, mainly because of their closer contact with people at high risk for HIV and better risk assessment skills. There is still no consensus as to who should be responsible for providing PrEP, but clearly all hands on deck will be useful in delivering on the international target of three million people at substantial risk for HIV on PrEP by 2020. Only about 5% of the target has been reached so far. Local guidance and large-scale education and information programs for clinicians will be necessary to upskill health providers. High cost of PrEP is still a major barrier for its broad implementation, even in countries were PrEP roll-out has started. Health services are facing major structural challenges due to implementation of PrEP services to a substantial volume of patients. The early implementation experiences demonstrated that PrEP can be successfully delivered across a variety of settings, and a broad range of strategies and models of care can streamline PrEP delivery. Education of the providers and PrEP cost solutions will be essential for rapid roll-out of PrEP.

The use of mobile phone apps by Australian gay and bisexual men to meet sex partners: an analysis of sex-seeking repertoires and risks for HIV and STIs using behavioural surveillance data.

BACKGROUND: Mobile phone apps are now the most popular method that Australian gay men use to find sex partners. Partner-seeking mobile phone apps use location functions to identify like-minded men and display their proximity. This study examines whether meeting partners via mobile apps is associated with a greater risk of HIV and sexually transmitted infections (STIs) than with other ways of meeting partners. METHODS: Data were analysed from the Gay Community Periodic Surveys, community-based, cross-sectional surveys conducted in Australian state capital cities between 2010 and 2014. χ2 tests and multinomial logistic regression were used to analyse differences in risk profiles of men who used different methods to meet partners. RESULTS: Data were analysed from 36 428 men who participated in the Gay Community Periodic Surveys between 2010 and 2014. In 2014, 4116 men reported meeting sex partners with the use of mobile apps, increasing from 23.9% in 2011 to 42.5% in 2014. Men who used a combination of online and offline methods reported a greater number of sex partners and were more likely to report a recent STI than men who used online methods only or offline methods only. CONCLUSIONS: There has been a steep increase in the use of mobile phone apps by gay men in Australia to meet male partners. However, men who use a combination of mobile phone apps, internet websites and offline places to meet partners appear to be at increased risk of STIs or HIV compared with men who use a narrower range of online and offline methods.

Social and Behavioural Correlates of HIV Testing Among Australian Gay and Bisexual Men in Regular Relationships.

In this study we sought to identify the social and behavioural characteristics of Australian gay and bisexual men who had and had not tested for HIV during their current relationship. The results were based on 2012 and 2013 data collected from ongoing cross-sectional and community-based surveys held in six Australian states and territories. One thousand five hundred and sixty-one non-HIV-positive men reported that they were in a primary relationship. The majority of gay and bisexual men in primary relationships had tested for HIV during the relationship (73.4 %). Among men who had not tested during the relationship, almost half of these men had never tested for HIV. As untested men within relationships are potentially at risk of acquiring and transmitting HIV to their partners unknowingly, it is important to promote HIV testing to these men.

The Meaning of 'Regular Partner' in HIV Research Among Gay and Bisexual Men: Implications of an Australian Cross-Sectional Survey.

Estimates of the proportion of HIV infections coming from within regular sexual relationships among gay and bisexual men (GBM) vary widely. Research surveys use various partner type categories, but there is little understanding of how men classify their partners. We conducted an online cross-sectional survey of Australian GBM exploring sexual relationships, including 2057 men reporting on 2566 regular partnerships. Just over half of the partnerships were considered 'relationships', while the remainder were non-romantic 'fuckbuddy'-style arrangements. In multivariable analysis, factors associated with considering the partnership a 'relationship' were: using a 'romantic' descriptor, partnership length, monogamous agreements, any condomless anal sex with each other, love, and commitment. The category of 'regular partner' can mask diverse partnership types, which have different meanings to GBM, associated behaviours, and HIV risks. Certain HIV prevention techniques may be more suited to particular types of partnerships. 'Fuckbuddy' arrangements need to be more explicitly acknowledged in HIV prevention.

Patterns of Drug Use and Drug-related Hospital Admissions in HIV-Positive and -Negative Gay and Bisexual Men.

We aimed to compare rates of illicit drug-related hospitalisations in HIV-negative (HIV-ve) (n = 1325) and HIV-positive (HIV+ve) (n = 557) gay and bisexual men (GBM) with rates seen in the general male population and to examine the association between self-reported illicit drug use and drug-related hospitalisation. Participants were asked how often they used a range of illicit drugs in the previous 6 months at annual interviews. Drug-related hospital admissions were defined as hospital admissions for mental or behavioural disorders due to illicit drug use (ICD 10: F11-16, F18, F19), drug poisoning (T40-T45, T50) or toxic effect of gases (T53, T59, T65). Drug-related hospitalisations were 4.8 times higher in the HIV-ve cohort [SIR 4.75 (95 % CI 3.30-6.91)] and 3.5 times higher in the HIV+ve cohort [SIR 3.51 (1.92-5.88)] compared with the general population. Periods of weekly drug use [IRR 1.86 (1.01-3.46)], poly-drug use [IRR 2.17 (1.07-4.38)] and cannabis use [low use-IRR 1.95 (1.01-3.77), high use-IRR 2.58 (1.29-5.16)] were associated with drug-related hospitalisation in both cohorts, as was being a consistently high meth/amphetamine user throughout follow-up [IRR 3.24 (1.07-9.83)] and being an inconsistent or consistent injecting drug user throughout follow-up [IRR 3.94 (1.61-9.66), IRR 4.43(1.04-18.76), respectively]. Other risk factors for drug-related hospitalisation indicated the likelihood of comorbid drug and mental health issues in GBM hospitalised for drug use.

Understanding Gay Community Subcultures: Implications for HIV Prevention.

Gay and bisexual men (GBM) who participate in gay community subcultures have different profiles, including differing risk behaviors. We examined men's participation in gay community subcultures, and its association with risk behavior. In a cross-sectional survey, 849 GBM provided information about men in their personal networks. We devised measures of their participation in five subcultural groupings and explored their associations with sexual behavior. We identified five subcultural groupings: sexually adventurous; bear tribes; alternative queer; party scene; and sexually conservative. Higher scores on the sexually adventurous measure was associated with being older, having more gay friends, being HIV-positive, and being more sexually active. It was also independently associated with unprotected anal intercourse with casual partners (AOR 1.82; 95 % CI 1.20-2.76; p = 0.005). HIV prevention strategies need to account for the different subcultural groupings in which GBM participate. Measures of engagement with gay subcultures are useful indicators of differential rates of risk behavior and modes of participation in gay community life. Men in more sexually adventurous subcultures are more likely to engage in sexual risk behavior.

Comprehensive testing for, and diagnosis of, sexually transmissible infections among Australian gay and bisexual men: findings from repeated, cross-sectional behavioural surveillance, 2003-2012.

OBJECTIVES: To analyse changes in testing for sexually transmissible infections (STI) among gay and bisexual men in Melbourne, Sydney and Queensland, Australia, particularly comprehensive STI testing (at least four tests from different anatomical sites in the previous year), and the characteristics of men who had such testing. METHOD: Data were analysed from repeated, cross-sectional, community-based surveys conducted during 2003-2012. Trends in specific STI tests and comprehensive testing were assessed and the characteristics of participants who reported comprehensive STI testing were identified using multivariate logistic regression, stratified by HIV status. RESULTS: Among HIV-negative and unknown status men (n=51 009), comprehensive STI and HIV testing increased substantially from 13% in 2003 to 34% in 2012. During the same period, comprehensive STI testing (excluding HIV testing) increased from 24% to 57% among HIV-positive men (n=5532). In both HIV status groups, comprehensive testing was more commonly reported by men who had unprotected anal intercourse with casual partners, and men with higher numbers of partners. Among HIV-negative/unknown status participants, comprehensive STI and HIV testing was also associated with education level, regional location and finding partners online. Among HIV-positive men, comprehensive STI testing was also associated with free time spent with gay men and illicit drug use. Comprehensive testing was related to a high annual rate of diagnosis with STIs (20% of HIV-negative/unknown status men and 38% of HIV-positive men). CONCLUSIONS: There has been a substantial improvement in the proportion of gay and bisexual men in Melbourne, Sydney and Queensland who report comprehensive testing. Comprehensive testing is most likely among men whose practices put them at increased risk of infection, and is associated with a high rate of STI diagnosis. However, opportunities for comprehensive testing are still being missed, suggesting a need for its ongoing promotion.

At home and away: gay men and high risk sexual practices.

We aimed to describe HIV risk practices of gay men who travel locally, regionally and overseas. We analysed data from the Sydney Gay Community Periodic Survey 2009 about high-risk sexual practices in four locations (locally, while travelling in NSW, Australia and overseas) and with partners of HIV positive, negative and unknown serostatus in each location. Analyses of associations used generalized log-binomial estimation procedures with Type I error of 5 %. Of 1,839 sexually active participants, 70.1 % reported having sex locally. 19.7 % elsewhere in NSW, 20.1 % interstate and 18 % overseas. Unprotected anal intercourse (UAI) was reported by 29.9, 28.6, 21.3 and 19.3 % of men in each location respectively. There was no difference in the levels of UAI locally and elsewhere in NSW, but UAI levels were lower in other Australian locations [adjusted prevalence rate ratio (APRR) = 0.76; 95 % confidence interval (95 % CI) 0.66-0.88] and overseas (APRR = 0.76; 95 % CI 0.65-0.89). UAI was more likely if partners were seroconcordant HIV positive (APRR = 1.67; 95 % CI 1.32-2.11) and less likely if partners were of different HIV serostatus (APRR = 0.39; 95 % CI 0.33-0.47) as compared to seroconcordant HIV negative partners. UAI was associated with group sex and use of party drugs. In this community sample, UAI levels were higher in the local context than in travel destinations, suggesting that familiarity between partners may play a role. High-risk sexual practices can nevertheless contribute to bridging different HIV epidemics and HIV transmission across borders. HIV prevention programs should develop effective approaches to target sexually adventurous gay men and HIV transmission associated with travel.

The Opposites Attract Study of viral load, HIV treatment and HIV transmission in serodiscordant homosexual male couples: design and methods.

BACKGROUND: Studies in heterosexual HIV serodiscordant couples have provided critical evidence on the role of HIV treatments and undetectable viral load in reducing the risk of HIV transmission. There is very limited data on the risk of transmission from anal sex in homosexual male serodiscordant couples. METHODS/DESIGN: The Opposites Attract Study is an observational prospective longitudinal cohort study of male homosexual serodiscordant partnerships running from 2012 to 2015 and conducted in clinics throughout Australia, Brazil and Thailand. Couples attend two or more clinic visits per year. The HIV-positive partner's viral load is tested and the HIV-negative partner is tested for HIV antibodies at every clinic visit. Results from any tests for sexually transmitted infections are also collected. Detailed behavioural questionnaires are completed by both partners at the time of each visit. The primary research question is whether HIV incidence is lower in those couples where the HIV-positive partner is receiving HIV treatment compared to couples where he is not receiving treatment. A voluntary semen sub-study will examine semen plasma viral load in a subsample of HIV-positive partners in Sydney, Rio de Janeiro and Bangkok. In cases of seroconversion of the initially HIV-negative partner, phylogenetic analysis will be conducted at the end of the study on virus from stored blood samples from both partners to determine if the infection came from the HIV-positive study partner. Men in new serodiscordant relationships will specifically be targeted for recruitment. DISCUSSION: This study will provide critical data on the reduction in HIV transmission risk associated with being on HIV treatment in homosexual male serodiscordant couples in different regions of the world. Data from men in new relationships will be particularly valuable given that the highest transmission risk is in the first year of serodiscordant relationships. Furthermore, the detailed behavioural and attitudinal data from the participant questionnaires will allow exploration of many contextual factors associated with HIV risk, condom use and the negotiation of sexual practice within couples.

Understanding of norms regarding sexual practices among gay men: literature review.

Since there is little evidence about gay community norms across the world, we reviewed published literature in this area and discuss implications for prevention and research. Eight databases were searched for articles and 16 were considered suitable for analysis. All used quantitative methodology and seven were based on a published theoretical framework. The most common theory employed by four out of the seven papers was the Theory of Reasoned Action. All papers reviewed examined norms on condom use but norms on other risk reduction practices were not explored in these papers. Seven (44 %) studies found those men who perceived strong social support from their peers, were less likely to engage in unprotected anal intercourse. This finding suggests that social support from partners and community members plays a role in shaping safe sex norms. Better understanding of norms may help to redress HIV behaviour change programmes, particularly at the time when HIV diagnoses rates are increasing in most gay communities across the world.