Number of risk acts by relationship status and partner serostatus: Findings from the HIM cohort of homosexually active men in Sydney, Australia

The need for pre-emptive control strategies for mpox in Asia and Oceania

Introduction

The transmission dynamics of the recent mpox outbreak highlights the lack of infrastructure available to rapidly respond to novel STI outbreaks, of which Asia and Oceania remains particularly susceptible. Here, we simulate outbreaks in this setting and propose the use of pre-emptive vaccination within the men who have sex with men (MSM) community before the arrival and establishment of the virus.

Materials and methods

Using data driven heterogeneous sexual contact networks, we simulated outbreaks of mpox in Singapore, Hong Kong, and Sydney. An individual based SEIR compartmental model was used to simulate epidemic trajectories and the impact of different vaccination uptakes was assessed in their ability to avert or suppress outbreaks upon the arrival of mpox within the MSM populations.

Results

The highly dense sexual networks of Singapore and Sydney experience rapid outbreaks, with infection peaks occurring at day 41 and 23 respectively, compared to Hong Kong which occurs at day 77. Across the simulations with no vaccination, 68.2%-89.7% of the MSM community will become infected with mpox across the different cities, over a simulation period of 1 year. By implementing vaccination strategies, the infection rate across the cities can be reduced to as low as 3.1% of the population (range: 3.1%-82.2%) depending on the implementation and uptake of the vaccine. Vaccination is also extremely effective in slowing the start of the epidemic, delaying the epidemic peak by 36-50 days in Hong Kong, or even preventing the outbreak of mpox.

Discussion

With extremely dense and well-connected sexual contact networks, where 65.2%-83.2% of the population are connected to a super-spreader in the different contact networks, pre-emptive or immediate vaccination upon identification of the first case is strongly recommended to help better manage the outbreak of mpox and prevent potential straining of healthcare systems.

A gonococcal vaccine has the potential to rapidly reduce the incidence of Neisseria gonorrhoeae infection among urban men who have sex with men

Background

A gonococcal vaccine is urgently needed due to increasing gonorrhea incidence and emerging multidrug-resistant gonococcal strains worldwide. Men who have sex with men (MSM) have among the highest incidences of gonorrhea and may be a key target population for vaccination when available.

Methods

An individual-based, anatomical site-specific mathematical model was used to simulate Neisseria gonorrhoeae transmission in a population of 10 000 MSM. The impact of vaccination on gonorrhea prevalence was assessed.

Results

With a gonococcal vaccine of 100% or 50% protective efficacy, gonorrhea prevalence could be reduced by 94% or 62%, respectively, within 2 years if 30% of MSM are vaccinated on presentation for sexually transmitted infection (STI) testing. Elimination of gonorrhea is possible within 8 years with vaccines of ≥ 50% efficacy lasting 2 years, providing a booster vaccination is available every 3 years on average. A vaccine’s impact may be reduced if it is not effective at all anatomical sites.

Conclusions

Our study indicates that with a vaccine of modest efficacy and an immunization strategy that targets MSM presenting for STI screening, the prevalence of gonorrhea in this population could be rapidly and substantially reduced.

Brief Report: Changes in Behavior After PrEP Initiation Among Australian Gay and Bisexual Men

INTRODUCTION

HIV pre-exposure prophylaxis (PrEP) has been increasingly adopted by gay and bisexual men (GBM). Little is known about whether individual GBM change their sexual behavior after PrEP initiation.

METHODS

Following Lives Undergoing Change (Flux) is a national, online, prospective observational study among Australian GBM. Using McNemar statistics, we compare rates of sexual behaviors before and coincident with PrEP initiation among 1518 non-HIV-positive men recruited between August 2014 and July 2017 who had not commenced PrEP at baseline and who completed at least one 6-monthly follow-up surveys by July 2018.

RESULTS

The proportion of men using PrEP rose to 24.2% over time. In total, 348 men initiated PrEP during follow-up. PrEP initiators were more likely to report particular sexual behaviors during the follow-up period that they commenced PrEP compared with the period immediately prior: receptive condomless anal intercourse with casual partners increased from 31.0% to 48.9% (McNemar < 0.001); mean partner number increased from 21.96 partners to 34.55 partners (p-trend < 0.001). Among the 1170 men who did not initiate PrEP, prevalence of these behaviors remained lower and stable. Sexual sensation-seeking and gay social engagement were both higher among men who commenced PrEP.

CONCLUSIONS

GBM tended to increase their engagement in "adventurous" sexual behaviors after PrEP initiation. Sexual behaviors among men who did not initiate PrEP were less common and did not change over time.

A cross-sectional study of the relationship between sexual compulsivity and unprotected anal intercourse among men who have sex with men in shanghai, China

Background

HIV prevalence among men who have sex with men (MSM) in China is rising rapidly, and unprotected anal intercourse (UAI) is associated with HIV transmission. Recent research has shown that associations between UAI and other factors can differ according to the type of sex partners, including regular partners and casual partners. This study aimed to explore the relationship between sexual compulsivity and UAI according to partner type among MSM in Shanghai, China.

Methods

A cross-sectional study was conducted among 547 MSM from four districts in Shanghai, China. All participants were recruited using snowball sampling. The Sexual Compulsivity Scale was used to evaluate participants’ sexual compulsivity. Multivariable logistic regression was used to identify factors associated with sexual compulsivity and UAI. The mediation effects of substance use before sex on the relationship between sexual compulsivity and UAI were tested through mediation analyses.

Results

After adjusting for sociodemographic variables, sexual compulsivity was associated with overall UAI (adjusted odds ratios [AOR] = 1.039, 95% confidence intervals [CI] = 1.004–1.075), UAI with non-regular sex partners (AOR = 1.089, 95% CI = 1.033–1.148) and UAI with commercial sex partners (AOR = 1.185, 95% CI = 1.042–1.349). No significant association was found between sexual compulsivity and UAI with regular sex partners (AOR = 1.029, 95% CI = 0.984–1.077). Mediation analyses indicated that the relationship between sexual compulsivity and UAI was not mediated by either alcohol use before sex or drug use before sex.

Conclusions

The association between sexual compulsivity and UAI varies depending on the type of UAI partner. Therefore, individuals may engage in different types of UAI for different reasons, and tailored HIV cognitive–behavioral intervention programs are needed.

Negotiated safety - components, context and use: an integrative literature review

AIM

The aim of this study was to examine the components and use of negotiated safety in the context of HIV prevention and to identify reported factors associated with the concept.

BACKGROUND

There is an emerging interest in dyadic approaches to address HIV transmission. Although there are theoretical foundations for how interpersonal relationships influence individual behaviour, how these dyadic processes influence on health is still not wholly understood.

DESIGN

Integrative review of empirical and theoretical literature.

DATA SOURCES

The Cumulative Index for Nursing and Allied Health Literature (CINAHL) MEDLINE and PsychINFO electronic databases were accessed.

REVIEW METHODS

Articles were read to gain a historical context of the term and identify varying interpretations of the concept. Factors warranting consideration in association with NS were identified and clinical and public health implications were noted.

RESULTS

Forty-eight studies were reviewed. Negotiated safety included the following components: (i) HIV sero-negative concordant men within a primary relationship; (ii) joint HIV screening and mutual disclosure of their HIV status; (iii) explicit relationship boundaries which establish either nonexclusively that allows for the dispensing of condoms within the primary relationship and consistent condom use for extra-dyadic sex; or dispensing of condoms within a primary partnership and exclusivity; and (iv) a breach clause that allows communication to re-establish the agreement if needed.

CONCLUSION

Negotiated safety is a prescriptive approach to HIV risk reduction among couples. Researchers and practitioners could benefit from promoting this approach to HIV prevention.

Identifying factors that lead to the persistence of imported gonorrhoeae strains: a modelling study

OBJECTIVE

The importation of Neisseria gonorrhoeae (NG) strains from overseas is believed to be the main source of antimicrobial resistance in Australia. With recent sporadic cases of ceftriaxone-resistant gonorrhoea reported in Australia and elsewhere, we sought to model the potential for imported NG strains to persist in the men who have sex with men (MSM) population in Australia.

METHODS

We developed an individual-based model to simulate the transmission of NG in a population of urban MSM, and used this model to investigate factors contributing to the probability that an imported NG strain will persist.

RESULTS

The probability of the imported NG strain persisting as the result of a single importation event is less than 1%, but the probability increases to 1% if the imported NG strain is resistant to treatment, and further increases to 3.1% if the imported NG strain can also form mixed infections with the local NG strain. The probability of the imported NG strain persisting increases to 4.4% if there are at least three importation events per month within a 1-year period.

CONCLUSION

The imported NG strain is unlikely to persist as a result of a single importation event. However, the probability of persistence increases if the imported NG strain is resistant to treatment, can form mixed infections with the local NG strain or there are frequent importation events. Identification of the factors that determine the likelihood of persistence of an imported NG strain could contribute to our capacity to respond appropriately and in a timely fashion.

A scoping review and thematic analysis of social and behavioural research among HIV-serodiscordant couples in high-income settings

BACKGROUND

While HIV incidence has stabilized in many settings, increases in health and wellbeing among many people living with HIV/AIDS suggest that the number of HIV-serodiscordant relationships is growing. Given the deficit of reviews addressing social and behavioural characteristics of HIV-serodiscordant couples within high-income settings, our objective was to understand the scope of the published literature, identify evidence gaps, and suggest future research needs.

METHODS

Ten electronic databases were searched. Studies were included if they were reported in English, used primary data, were from the combination antiretroviral (cART) era (>1996), reported on social or behavioural aspects, included any fraction of primary (i.e., stable) relationships, and were conducted in high-income settings. Studies that identified their unit of analysis as either the dyad or individual member of the couple were included. Studies were coded according to a thematic framework.

RESULTS

Included studies (n = 154) clustered into eight themes: risk behaviours (29%), risk management (26%), reproductive issues (12%), relationship quality (9%), serostatus disclosure (7%), adherence to antiretroviral therapy (7%), vulnerability (5%), and social support (3%). The proportion of studies conducted among heterosexual couples, same-sex male couples, and mixed cohorts were 42%, 34%, and 24%, respectively. Most studies (70%) were conducted in the United States, 70% of all studies were quantitative (including interventions), but only one-third were focused on couples (dyads) where both partners are recruited to a study. Over 25% of studies focused on sexual risk among same-sex male couples.

CONCLUSIONS

Future research efforts should focus on the interrelationship of risk management strategies and relationship quality, social determinants of health and wellbeing, HIV testing, vulnerable populations, reproductive issues among same-sex couples, disclosure of serodiscordant status to social networks, dyadic studies, population-based studies, and interventions to support risk management within couples. Additional population-based studies and studies among marginalized groups would be helpful for targeting research and interventions to couples that are most in need. As HIV-positive partners are typically the link to services and research, innovative ways are needed for reaching out to HIV-negative partners. Our review suggests that significantly more research is needed to understand the social and behavioural contexts of HIV-serodiscordant relationships.

Oral and anal sex are key to sustaining gonorrhoea at endemic levels in MSM populations: a mathematical model

OBJECTIVES

Despite early treatment of urethral infection, gonorrhoea is endemic in urban populations of men who have sex with men (MSM) in Australia. By contrast, gonorrhoea is not common in urban heterosexual populations. Sexual activities among MSM usually involve anal or oral sex, and as these behaviours are becoming increasingly common among heterosexuals, there is a need to investigate their roles in transmission of gonorrhoea.

METHODS

We developed individual-based models of transmission of gonorrhoea in MSM and heterosexuals that incorporate anatomical site-specific transmission of gonorrhoea. We estimated the probabilities of transmission for anal sex and oral sex by calibrating an MSM model against prevalence of gonorrhoea and sexual activity data. These probabilities were then applied to a heterosexual model in order to examine whether gonorrhoea can persist in a heterosexual population through the addition of anal sex and oral sex.

RESULTS

In the MSM model, gonorrhoea can persist despite prompt treatment of urethral infections. The probability of gonorrhoea persisting is reduced if use of condom for oral sex is increased to more than 15% of acts. Assuming that treatment of symptomatic infections is prompt, gonorrhoea is unlikely to persist in a heterosexual population even with the addition of anal and oral sex.

CONCLUSIONS

Our models suggest that oral sex has an important role in sustaining gonorrhoea in a population of MSM by providing a pool of untreated asymptomatic infection. The importance of anal sex or oral sex in sustaining gonorrhoea in a heterosexual population remains uncertain due to the lack of information linking different types of sex acts and transmissibility.

Strong propensity for HIV transmission among men who have sex with men in Vietnam: behavioural data and sexual network modelling

OBJECTIVES

Survey data from men who have sex with men (MSM) in Asian cities indicate ongoing and drastic increases in HIV prevalence. It is unknown which behavioural factors are most important in driving these epidemics. We aimed to analyse detailed sexual behaviour data among MSM in Vietnam and to model HIV transmission using improved assumptions on sexual network structure.

SETTING

Vietnam.

PARTICIPANTS

Internet-using men who had ever had sex (any type) with a man, aged ≥18 years and living in Vietnam. The study was cross-sectional, population-based and performed in 2012, using online respondent-driven sampling. The Internet-based survey instrument was completed by 982 participants, of which 857 were eligible. Questions included sociodemography and retrospective sexual behaviour, including number of unprotected anal sex (UAS) acts per partner.

PRIMARY AND SECONDARY OUTCOME MEASURES

Estimated basic reproductive number over 3 months as a function of transmission risk per UAS act; frequency distributions of number of UAS partners and UAS acts during last 3 months.

RESULTS

36% (CI 32% to 42%) reported UAS at least once during the last 3 months. 36% (CI 32% to 41%) had ever taken an HIV test and received the result. UAS partner numbers and number of UAS acts were both highly skewed and positively correlated. Using a weighted configuration model, taking into account partner numbers, frequency of UAS and their correlations, we estimated the basic reproductive number (R0) over 3 months. The results indicated rapid transmission over a wide range of values of per-act transmissibility.

CONCLUSIONS

Men with multiple partners had unexpectedly high UAS frequency per partner, paired with low HIV testing rates. The study highlights the importance of collecting data on frequency of UAS acts and indicates the need to rapidly scale-up HIV prevention services and testing opportunities for MSM in Vietnam.

Sexual risk behaviors by relationship type and trauma history among HIV-positive men who have sex with men

The association of trauma exposure and coping style to sexual risk behavior has yet to be fully examined in the context of primary and casual sexual partnerships. The current study assessed a high risk sexual behavior-unprotected anal intercourse (UAI)-in a high risk population of HIV-positive men who have sex with men (MSM) with a history of trauma. Using audio computer-assisted self-interview technology, 132 HIV-positive MSM completed measures of trauma exposure, trauma symptoms, coping strategies, and sexual risk behavior. Hierarchical logistic regression analyses indicated that completing more years of education and having experienced sexual abuse were positively associated with UAI with casual partners. Additionally, use of active coping was negatively associated with UAI with casual partners and the final model significantly predicted variance in UAI with casual partners. However, no variables were significantly associated with UAI with primary partners, suggesting that sexual risk behavior with primary partners may be associated with factors not commonly assessed in risk prediction or prevention research. We discuss the results in the context of developing new or modifying existing interventions to address rates of sexual risk in the relationships of HIV-positive MSM.

An economic case for providing free access to antiretroviral therapy for HIV-positive people in South Australia

BACKGROUND

As financial constraints can be a barrier to accessing HIV antiretroviral therapy (ART), we argue for the removal of copayment requirements from HIV medications in South Australia.

METHODS

Using a simple mathematical model informed by available behavioural and biological data and reflecting the HIV epidemiology in South Australia, we calculated the expected number of new HIV transmissions caused by persons who are not currently on ART compared with transmissions for people on ART. The extra financial investment required to cover the copayments to prevent an HIV infection was compared with the treatment costs saved due to averting HIV infections.

RESULTS

It was estimated that one HIV infection is prevented per year for every 31.4 persons (median, 24.0-42.7 interquartile range (IQR)) who receive treatment. By considering the incremental change in costs and outcomes of a change in program from the current status quo, it would cost the health sector $17860 per infection averted (median, $13651-24287 IQR) if ART is provided as a three-dose, three-drug combination without requirements for user-pay copayments.

CONCLUSIONS

The costs of removing copayment fees for ART are less than the costs of treating extra HIV infections that would result under current conditions. Removing the copayment requirement for HIV medication would be cost-effective from a governmental perspective.

Distributions and trends in sexual behaviors and HIV incidence among men who have sex with men in China

Background

HIV prevalence is increasing at a concerning rate among men who have sex with men (MSM) in China. Numerous studies have reported on levels of behaviors of Chinese MSM for different types of sexual partnerships, such as regular, non-commercial casual and commercial. This study aims to investigate the trends HIV incidence rates in relation to their risk sexual behaviors and partnership types among Chinese MSM.

Method

Through a comprehensive literature research from available English and Chinese literature databases, we collated relevant information of sexual behaviors of Chinese MSM. Further, with the utilization of a mathematical optimization approach, this study reconciles the distributions of sexual behavioral data over the last decade and infers the heterogeneous distributions of behavioral patterns among Chinese MSM. Distributions of high-risk behavioural indicators, including the number of sexual partners, number of sexual acts and condom usage in the past 6 months, are calibrated to available empirical data. Based on the resultant temporal trends in these distributions, the trends in HIV incidence rates associated with each type of partnership among MSM in China are also estimated.

Results

A total of 55 qualified articles have been identified. An average MSM has approximately 0.96 (95% CI, 0.59-1.18) regular, 3.75 (1.72-6.25) casual and 1.61 (0.97-2.78) commercial partners over a 6 month period and 4.33 (2.81-6.46), 1.42 (0.62-3.08), 1.48 (0.79-3.30) sexual acts per partnership respectively, corresponding to a total of 11.87 (8.87-15.25) acts. Condom usage has increased significantly during 2002–2010, at annual increases of 3.58% (2.98-4.12%), 5.55% (4.55-6.54%), and 5.03% (4.19-5.74%) for regular, casual and commercial partners respectively. These behavioral data implies an increase in HIV incidence of approximately 3.3-fold, from 2.04 (1.96-2.12) to 7.02 (6.71-7.35) per 1000 person-years during the same period. The proportion of new infections attributed to regular partnerships increased from 34% to 40%, whereas infections attributed to commercial partnerships reduced from 29% to 23% during 2002–2010.

Conclusion

Regular partnerships are the main contributor of new HIV cases among MSM in China, public health intervention strategies are required to increase condom usage and HIV testing rates among regular partners to curb the growing trend HIV incidence.

Partner-provided social support influences choice of risk reduction strategies in gay male couples

We investigated the influence of partner-provided HIV-specific and general social support on the sexual risk behavior of gay male couples with concordant, discordant, or serostatus-unknown outside partners. Participants were 566 gay male couples from the San Francisco Bay Area. HIV-specific social support was a consistent predictor for reduced unprotected anal intercourse (UAI) with both concordant outside partners (all couple types) and outside partners of discordant or unknown serostatus (concordant negative and discordant couples). General social support was associated with increased UAI with concordant outside partners for concordant negative and concordant positive couples (i.e., serosorting). Our findings suggest that prevention efforts should target couples and identify the level of HIV-specific support that partners provide. Partner-provided support for HIV-related behaviors could be an additional construct to consider in gay male relationships, akin to relationship satisfaction and commitment, as well as an important component of future HIV prevention interventions.

Is injection serosorting occurring among HIV-positive injection drug users? Comparison by injection partner's HIV status

Research needs to build evidence for the roles that HIV status of injection partners may or may not play in injection risk behaviors of injection drug users (IDUs). Using baseline data collected from a randomized controlled study (INSPIRE) conducted in four cities (Baltimore, Miami, New York, and San Francisco) from 2001 to 2005, we categorized 759 primarily heterosexual HIV-positive IDUs into four groups based on HIV serostatus of drug injection partners. Thirty-two percent of the sample injected exclusively with HIV-positive partners in the past 3 months and more than 60% had risky injection behavior with these partners. Eight percent injected exclusively with HIV-negative partners and 49% injected with any unknown status partners. The remaining 11% reported having both HIV-positive and -negative injection partners, but no partners of unknown HIV status. Riskier injection behavior was found among the group with mixed status partners. The risk among the group with any unknown status partners appeared to be driven by the greater number of injection partners. No major group differences were observed in socio-demographic and psychosocial factors. Our analysis suggests that serosorting appeared to be occurring among some, but not an overwhelming majority of HIV-positive IDUs, and knowledge of HIV status of all injection partners per se did not appear to be as important as knowledge of sexual partner's HIV status in its association with risk behavior.

Achieving Safety: Safer Sex, Communication, and Desire among Young Gay Men

Conceptualizations of safer sex practices among young gay men (YGM) are frequently structured around communication between partners and the subsequent utilization or absence of condoms in a sexual encounter. Drawing on a sample of 34 in-depth interviews with YGM, ages 18 to 24, we explore the ways in which conceptualizations and definitions of safer sex are discussed and enacted. Placing attention on their safer sex practices, we analyze the conversations that do and do not occur among YGM and their partners, including the strategies (e.g., negotiated safety, condom communication and negotiation) that are commonly perceived as most useful by YGM. We provide recommendations regarding how to craft safer sex messages for YGM by considering their competing demands.

Stressful events, avoidance coping, and unprotected anal sex among gay and bisexual men

This study examined associations among stressful life events, avoidance coping, and unprotected anal sex (UAS) in a convenience sample of 297 men obtained through the Internet and who either reported having sex with men or self-identified as gay or bisexual. Participants completed an Internet-hosted self-administered questionnaire that included measures of victimization experiences and other stressful life events, and avoidance coping. More than half of the sample reported engaging in UAS during the previous 6 months. Victimization predicted UAS regardless of partner type; victimization, HIV-positive serostatus, and avoidance coping predicted UAS with nonprimary partners. The findings provide evidence that American gay and bisexual men may experience a variety of stressful life events, including a surprising amount of victimization, and that at least some episodes of UAS may be associated with attempts to cope with distress associated with such events.

Is sexual serosorting occurring among HIV-positive injection drug users? Comparison between those with HIV-positive partners only, HIV-negative partners only, and those with any partners of unknown status

Using baseline data from a multi-site, randomized controlled study (INSPIRE), we categorized 999 HIV-positive IDUs into three groups based on serostatus of their sex partners. Our data provide some evidence for serosorting occurring in our sample; about 40% of the sample had sex exclusively with HIV-positive partners, and about half of them reported having unprotected sex with these partners. Twenty per cent had sex exclusively with HIV-negative partners; their sexual behaviors tended to be least risky with about two-thirds reporting their sex was protected. However, we also found that another 40% had at least one partner of unknown HIV status and sexual and drug risk was the highest among them. They were also least empowered, showing attributes that may undermine HIV prevention. Some of these findings are consistent with findings from MSM studies, suggesting that partner selection practices are similar between primarily heterosexual IDUs and MSM.

Development and validation of the sexual agreement investment scale

Sexual agreements are ubiquitous among gay men. Lower levels of investment in these agreements may be associated with breaking them or engaging in risky sexual behavior. A scale was developed to measure agreement investment levels among gay men. Qualitative data from 78 gay men in committed relationships were analyzed to inform item development, followed by quantitative analyses of two larger samples (n = 380, n = 1,001) to assess construct, convergent, and discriminant validity. The Sexual Agreement Investment Scale (SAIS) is a psychometrically sound measure of the level of investment in sexual agreements among gay men in relationships. Men with higher agreement investment were less likely to break agreements and less likely to engage in unprotected anal intercourse with outside partners. The SAIS can be used to measure investment in sexual agreements and its impact on sexual behavior in a wide variety of settings, including research on relationships, sexuality, couples therapy and HIV prevention.

Circumcision and risk of HIV infection in Australian homosexual men

OBJECTIVE

To assess circumcision status as a risk factor for HIV seroconversion in homosexual men.

DESIGN, SETTING AND PARTICIPANTS

The Health in Men (HIM) study was a prospective cohort of homosexual men in Sydney, Australia. HIV-negative men (n = 1426) were recruited primarily from community-based sources between 2001 and 2004 and followed to mid-2007. Participants underwent annual HIV testing, and detailed information on sexual risk behaviour was collected every 6 months.

MAIN OUTCOME MEASURE

HIV incidence in circumcised compared with uncircumcised participants, stratified by whether or not men predominantly practised the insertive role in anal intercourse.

RESULTS

There were 53 HIV seroconversions during follow-up; an incidence of 0.78 per 100 person-years. On multivariate analysis controlling for behavioural risk factors, being circumcised was associated with a nonsignificant reduction in risk of HIV seroconversion [hazard ratio 0.78, 95% confidence interval (CI) 0.42-1.45, P = 0.424]. Among one-third of study participants who reported a preference for the insertive role in anal intercourse, being circumcised was associated with a significant reduction in HIV incidence after controlling for age and unprotected anal intercourse (UAI) (hazard ratio 0.11, 95% CI 0.03-0.80, P = 0.041). Those who reported a preference for the insertive role overwhelmingly practised insertive rather than receptive UAI.

CONCLUSIONS

Overall, circumcision did not significantly reduce the risk of HIV infection in the HIM cohort. However, it was associated with a significant reduction in HIV incidence among those participants who reported a preference for the insertive role in anal intercourse. Circumcision may have a role as an HIV prevention intervention in this subset of homosexual men.

Intensive sex partying amongst gay men in Sydney

Intensive sex partying is a framework developed to analyse specific frequent behaviours amongst a small minority of gay men in Sydney, Australia. The behaviours included a higher frequency of dance party attendance, more frequent sex, more anal sex, multiple sex partners, more unprotected anal intercourse with casual partners and more frequent drug taking. These occur at a contextual intersection between a sub-group of sexually adventurous gay men and 'party boys'. The men appear to be involved in both high-risk, adventurous sex practices and a specific form of partying distinguishable from dance partying and 'clubbing'. Sex partying occurs on multiple sites (domestic spaces; within dance parties; sex parties; sex-on-premises venues) and appears to be geared to the maximisation of sexual pleasure. Intensive sex partying describes this coincidence of factors and locates them in relation to the multiple pleasures offered by sex partying. It emphasises the importance of 'intensity' in order to understand better the relations between sex, drug use, pleasure, care and risk in some gay men's lives.

Importance of promoting HIV testing for preventing secondary transmissions: modelling the Australian HIV epidemic among men who have sex with men

BACKGROUND

We address the research questions: (i) what proportion of new HIV infections is transmitted from people who are (a) undiagnosed, (b) in primary HIV infection (PHI), (c) on antiretroviral therapy?; and (ii) what is the expected epidemiological impact of (a) increasing the proportion of newly acquired HIV infections receiving early treatment, and (b) increasing HIV testing rates?

METHODS

We used a mathematical model to simulate HIV transmission in the population of men who have sex with men (MSM) in Australia. We calibrated the model using established biological and clinical data and a wide range of Australian MSM epidemiological and behavioural data sources.

RESULTS

We estimate that ~19% of all new HIV infections are transmitted from the ~3% of Australian HIV-infected MSM who are in PHI; ~31% of new HIV infections are estimated to be transmitted from the ~9% of MSM with undiagnosed HIV. We estimate that the average number of infections caused per HIV-infected MSM through the duration of PHI is ~0.14-0.28.

CONCLUSIONS

The epidemiological impact of increasing treatment in PHI would be modest due to insufficient detection of newly-infected individuals. In contrast, increases in HIV testing rates could have substantial epidemiological consequences. The benefit of testing will also increase over time. Promoting increases in the coverage and frequency of testing for HIV could be a highly-effective public health intervention, but the population-level impact of interventions based on promoting early treatment of patients diagnosed in PHI is likely to be small. Treating PHI requires further evaluation of its long-term effects on HIV-infected individuals.

HIV testing frequency among men who have sex with men attending sexually transmitted disease clinics: implications for HIV prevention and surveillance

OBJECTIVES

To describe trends in the occurrence and frequency of HIV testing among men who have sex with men (MSM) receiving care in 4 US sexually transmitted disease (STD) clinics and to define factors associated with HIV testing frequency and positivity.

STUDY DESIGN

Routine clinical encounters during 57,131 visits by MSM to STD clinics in 4 cities (Seattle-King County, San Francisco, Denver, and District of columbia), 2002-2006, were examined.

RESULTS

From 2002 to 2006, a city-specific median of 69.1% of presumptive HIV-uninfected MSM were tested for HIV, of which, a median of 86.7% had previously tested (4.5% unknown) and a median of 3.9% were newly diagnosed with HIV. Between 2002 and 2006, the median percentage of tested MSM who reported no previous HIV testing decreased from 9.4% to 5.4% (P = 0.01) and the city-specific median intertest interval decreased from 302 to 243 days (P = 0.03). Among MSM with newly diagnosed HIV, the median intertest interval decreased from 531 days in 2002 to 287 days in 2006 (P = 0.001). Predictors of newly diagnosed HIV infection included the following: younger age, longer intertest interval, black or Hispanic race/ethnicity, clinic in San Francisco, and concurrent diagnosis with a bacterial STD.

CONCLUSIONS

In MSM seen at 4 STD clinics, the percentage of never previously HIV tested is decreasing and MSM are testing more frequently.

Differing trends in sexual risk behaviours in three Australian states: New South Wales, Victoria and Queensland, 1998-2006

BACKGROUND

In Australia, the HIV epidemic is concentrated among gay men. In recent years, the number of new diagnoses stabilised in New South Wales (NSW), but increased in other states. We reviewed the trends in sexual behaviours to explain this difference.

METHODS

We used the Gay Community Periodic Surveys in NSW, Victoria and Queensland during 1998-2006 and restricted analyses to the 30-49 year olds who contribute most of the HIV cases. We used the chi(2)-test for trends in unprotected anal intercourse with casual partners (UAIC) and regular partners, number of partners, type of relationships, knowledge of HIV serostatus and its disclosure. We compared behaviours of HIV-positive and -negative men and men across states using logistic regression adjusted for the year of report.

RESULTS

Trends in behaviours differed across the states: following a period of increase, UAIC prevalence declined in NSW since 2001, but continued to increase in Victoria and Queensland. There were other changes in NSW that were not observed in Victoria and Queensland: a decline in factors increasing HIV risk (the proportions of men with multiple sex partners and men engaging in UAIC and not knowing or not disclosing HIV serostatus) and an increase in behaviours reducing it (the proportions of men in monogamous relationships and men disclosing HIV serostatus while having UAIC).

CONCLUSION

There were patterns of declining HIV risk behaviours in NSW, and increasing risk behaviours elsewhere, that mirrored recent changes in HIV case notifications in Australia. These data suggest that behavioural surveillance can predict changes in HIV epidemiology.

Sexual practices of gay, bisexual, and other nonidentified MSM attending New York City gyms: patterns of serosorting, strategic positioning, and context selection

This descriptive paper characterizes the sexual behaviors of a diverse sample (N=311) of gay, bisexual, and other nonidentified men who have sex with men (MSM) who regularly attended gyms in New York City. Approximately 50% of the sample indicated sex with primary male partners, while 88% of the men had sexual relations with male casual partners in the 6 months prior to assessment. The participants met their casual partners in a variety of different venues, including the Internet. Differences were noted along key demographic factors with regard to the contexts in which men met their partners. The data indicate that the men use serosorting, strategic positioning, and contexts in which they meet other men, to influence choices concerning sexual partners and practices as a form of health protection. It is proposed that these patterns of sexual behavior are representative of the totality of the lives of gay, bisexual, and other MSM, because despite engaging in gym behaviors, which might be considered health promoting, these men are simultaneously taking risks. Such findings point to varying motivations as to why gay, bisexual, and other MSM actually attend the gym.

Using mathematical modelling to help explain the differential increase in HIV incidence in New South Wales, Victoria and Queensland: importance of other sexually transmissible infections

Background: Since 1999 there has been an increase in the number of HIV diagnoses in Australia, predominantly among men who have sex with men (MSM), but the magnitude of increase differs between states: ~7% rise in New South Wales, ~96% rise in Victoria, and ~68% rise in Queensland. Methods: Epidemiological, clinical, behavioural and biological data were collated into a mechanistic mathematical model to explore possible reasons for this increase in HIV notifications in MSM. The model was then used to make projections to 2015 under various scenarios. Results: The model suggests that trends in clinical and behavioural parameters, including increases in unprotected anal intercourse, cannot explain the magnitude of the observed rise in HIV notifications, without a substantial increase in a ‘transmission-increasing’ factor. We suggest that a highly plausible biological factor is an increase in the prevalence of other sexually transmissible infections (STI). It was found that New South Wales required an ~2-fold increase in other STI to match the data, Victoria needed an ~11-fold increase, and Queensland required an ~9-fold increase. This is consistent with observed trends in Australia for some STI in recent years. Future projections also indicate that the best way to control the current rise in HIV notifications is to reduce the prevalence of other STI and to promote condom use, testing for HIV, and initiation of early treatment in MSM diagnosed during primary infection. Conclusions: Our model can explain the recent rise in HIV notifications with an increase in the prevalence of other STI. This analysis highlights that further investigation into the causes and impact of other STI is warranted in Australia, particularly in Victoria.

The public health impact of widespread availability of nonoccupational postexposure prophylaxis against HIV

OBJECTIVE

The aim of the study was to describe the use of nonoccupational postexposure prophylaxis (NPEP) in Australia, and to estimate the number of HIV infections that its use prevented.

METHODS

We conducted a population-based observational cohort study of people who presented to antiretroviral prescribers in Eastern Australia, and reported a high-risk nonoccupational exposure to HIV, in 1998-2004. Prescribers collected data at baseline, 4 weeks and 6 months. Data collected included details of HIV exposure, drug regimens and HIV serostatus.

RESULTS

The great majority of the 1601 participants were male (95%) and presented after male homosexual exposure (87%). Only 32% of exposures were to HIV-positive sources. Two antiretroviral drugs were prescribed after 48% of events, and three or more drugs after 52% of events. The median time to receipt of NPEP was 23 h. Side effects were reported by 66% of participants. No case of NPEP failure in an adherent individual was identified. It was estimated that 0.9-9.2 HIV infections had been prevented. This compared with a total of 1138 newly acquired HIV infections notified in the geographical area covered by the study.

CONCLUSIONS

In Australia, NPEP has been widely prescribed and is mainly targeted at high-risk exposures. Although there were no identified failures of NPEP, it is likely that only a small proportion of new HIV infections in the study area were prevented. NPEP may be a valuable preventive intervention for an individual, but it can only play a minor role in HIV prevention at the population level unless targeting can be further improved.

Condom Use Rather Than Serosorting Explains Differences in HIV Incidence Among Men Who Have Sex With Men

BACKGROUND

HIV incidence is high and increasing among men who have sex with men (MSM) attending the Sexually Transmitted Infection (STI) Outpatient Clinic in Amsterdam but remains low among MSM in the Amsterdam Cohort Studies (ACS). We studied whether sexual behaviors in these 2 groups are consistent with serosorting and if serosorting explains the difference in HIV incidence.

METHODS

In 2004 to 2006, a survey of sexual behaviors and HIV status regarding up to 4 traceable partners in the prior 6 months was performed in MSM attending the STI Outpatient Clinic (high-risk) and in MSM in the ACS (lower risk). Moreover, pooled information was collected on anonymous partners. We used logistic regression to test whether sexual behaviors are consistent with serosorting and to test whether risk group is associated with having concordant traceable partners among men reporting unprotected anal intercourse (UAI).

RESULTS

We included 513 MSM (54% lower risk and 75% HIV-negative). Lower risk and high-risk MSM with concordant traceable partners were more likely to have UAI than MSM with discordant partners or partners of unknown HIV status (P < 0.001). Risk group was not associated with having concordant UAI. Compared with lower risk MSM, however, high-risk MSM frequently had UAI with nonconcordant traceable partners and with anonymous partners.

CONCLUSIONS

Sexual risk behaviors with traceable partners are consistent with serosorting. Nonetheless, the higher level of UAI with anonymous or nonconcordant traceable partners more likely explains the increasing HIV incidence seen among STI Outpatient Clinic attendees than a difference in serosorting behavior.

Risk factors for genital and anal warts in a prospective cohort of HIV-negative homosexual men: the HIM study

OBJECTIVE

The objective of this study was to determine the prevalence, incidence, and risk factors for genital and anal warts in HIV-negative homosexual men in Sydney.

STUDY DESIGN

The authors conducted a prospective cohort study. Participants were asked whether they had had genital and anal warts at each interview. Details of lifetime sexual contacts and sexual behaviors in the last 6 months were collected.

RESULTS

Among 1,427 men recruited, 8.9% and 19.6% reported a history of genital and anal warts at baseline, respectively. Incidence rates for genital and anal warts were 0.94 and 1.92 per 100 person-years, respectively. In multivariate analysis, both incident genital and anal warts were associated with younger age. In addition, incident genital warts was associated with insertive fingering (P trend = 0.018), whereas incident anal warts was associated with insertive fingering (P trend = 0.007) and insertive fisting (P trend = 0.039).

CONCLUSIONS

Anal warts were twice as common as genital warts. Fingering and other manual sexual practices may be an important transmission route for both.

Differences between HIV-positive gay men who 'frequently', 'sometimes' or 'never' engage in unprotected anal intercourse with serononconcordant casual partners: positive Health cohort, Australia

By measuring the actual number of risk acts engaged in by HIV-positive men participating in the Positive Health (PH) cohort study, this paper sets out to document the distribution of risk acts, to report on the proportion of acts of unprotected anal intercourse with casual (UAIC) partners that occurred between HIV-positive men (i.e. seroconcordant positive) and to examine the factors that differentiated men who 'frequently' compared with 'sometimes' or 'never' engaged in unsafe UAIC (i.e. UAIC with serononconcordant partners: partners who have not tested positive for HIV). The findings show that 42.6% of all UAIC acts occurred between seroconcordant HIV-positive partners, posing no risk of HIV infection to an HIV-negative person. A minority of participants (10%) accounted for the majority (70.7%) of the unsafe acts of UAIC. The HIV-positive men who 'sometimes' engaged in unsafe UAIC had higher treatment optimism scores and were more likely to use Viagra in comparison with those who did not engage in such risk. Those who reported 'frequent' engagement in unsafe UAIC were more likely to engage in a range of esoteric sexual practices, be slightly less well educated and be taking antiretroviral therapy compared with HIV-positive men who 'sometimes' engaged in unsafe UAIC. As such, taking ART but not viral load, predicted frequent unsafe UAIC. When considered alongside earlier studies, these results suggest that HIV-negative men who engage in esoteric sexual practices may be at increased risk of HIV transmission, not necessarily because they engage in esoteric sex practices but because of the sub-cultural milieu in which esoteric sex is occurring. The findings from this study also endorse the measurement of UAIC acts as a useful gauge of risk.

[Prevention strategies to control the HIV epidemic. Successes, problems, and perspectives]

After the recognition of AIDS as a new disease entity and isolation of HIV as the causative agent in the early 1980s, a controversial debate about adequate measures to reduce the spread of HIV developed. In all developed countries a strategy based on education about modes of HIV transmission, condom promotion and harm reduction approaches to intravenous drug use finally succeeded and became instrumental for the relative containment of HIV within most at risk populations. However, in most developing countries as well as in the countries of Eastern Europe, the success of HIV pre vention remained limited for various reasons. In addition, for several years now, in the western developed countries sexual risk behaviour, newly diagnosed HIV infections, and the incidence of various other sexually transmitted infections seem to re-increase, especially among men who have sex with men (MSM). These increases coincide with a dramatic improvement of therapeutic options for the treatment of HIV infection. The relationship between improvement of therapy and changes in sexual risk behaviour has to be further defined. It is hypothesized that HIV serosorting as a predominant risk management strategy among MSM results in an accumulation of health risks in the HIV-positive MSM population. In addition to and beyond established condom promotion, additional biomedical approaches to reduce transmissibility and susceptibility for HIV will be necessary to regain control of the spread of HIV in highly sexually active populations.

A new surveillance system for monitoring HIV infection in Victoria, Australia

Objectives: To establish a new mechanism for monitoring patterns of HIV infection, in the context of a sustained increase in HIV diagnosis among men who have sex with men (MSM) in Victoria. Methods: Between April 2004 and August 2005, a linked voluntary HIV sentinel surveillance system was implemented at five medical clinics with a high case load of MSM. Using a questionnaire, doctors collected HIV testing history, demographic and sexual risk behaviour information from all clients undergoing voluntary HIV testing. Questionnaires were linked with HIV test results. Logistic regression analysis was conducted to determine factors associated with HIV infection. Results: Of 3435 MSM tested for HIV at participating sites, 1.7%, (95% CI = 1.2–2.2) were newly diagnosed with HIV; between 2004 and 2005 the proportion increased from 1.3% (95% CI = 1.2–1.5) to 2.0% (95% CI = 1.8–2.2), P = 0.107. There was no significant change in the number of HIV tests conducted per month or in demographic characteristics, testing history and sexual behaviour characteristics between time periods. In multivariate analysis, reporting unprotected anal intercourse (UAI) with any partner, UAI with a HIV-positive partner/s and being aged 30–39 years or 40 years or greater were significantly associated with HIV infection. Conclusion: This new surveillance mechanism, based on linked testing at participating clinics, indicates that the increase in HIV notifications in 2005 was unrelated to changes in testing and data from a Melbourne sexual behavioural survey suggests the increase was more likely to be attributed to increases in transmission within the past few years. The sentinel system highlighted UAI, especially with HIV positive partner/s are important transmission factors.

Bathhouse-Based Voluntary Counseling and Testing Is Feasible and Shows Preliminary Evidence of Effectiveness

The goal of this study was to provide evidence for the feasibility and effectiveness of conducting voluntary counseling and testing (VCT) for HIV in a bathhouse setting. Four hundred ninety-two men participated in bathhouse-based VCT offered at a single venue over a 13-month period. A convenience sample of 133 of these testers was assessed at 2 points: immediately before and 3 months after testing. Thirty-eight percent of men in the sample reported unprotected anal intercourse (UAI) with 1 of their 2 most recent partners in the 3 months before testing, and 48% of those men had not otherwise been tested for HIV in the previous 12 months. Results showed that in the months after VCT, men were less likely to engage in UAI, decreased their frequency of engaging in sex while drunk or high, and were more likely to communicate about HIV with their sexual partners. Bathhouse-based VCT seems to be a feasible approach for reaching significant numbers of men at risk for HIV and shows preliminary evidence of effectiveness in changing some specific HIV-related risk and precautionary behaviors.