HIV-positive Partner Research Articles

Actual sexual risk and perceived risk of HIV acquisition among HIV-negative men who have sex with men in Toronto, Canada.

BackgroundTheory suggests that perceived human immunodeficiency virus (HIV) risk and actual HIV risk behaviour are cyclical whereby engaging in high risk behaviour can increase perceived risk, which initiates precautionary behaviour that reduces actual risk, and with time reduces perceived risk. While current perceived risk may impact future actual risk, it is less clear how previous actual risk shapes current perceived risk. If individuals do not base their current perceived risk on past behaviour, they lose the protective effect of perceived risk motivating precautionary behaviour. Our goal was to determine the impact of actual risk on perceived risk.MethodsSexually active men who have sex with men (MSM) were recruited at the Maple Leaf Medical Clinic in downtown Toronto from September 2010 to June 2012. Participants completed a socio-behavioural questionnaire using an Audio Computer Assisted Self-Interview (ACASI). Actual HIV risk (primary predictor) was constructed by applying principal component analysis (PCA) to eight sexual risk survey questions and comprised three components which reflected sex with casual partners, sex with HIV-positive regular partners and sex with HIV unknown status regular partners. Perceived HIV risk (outcome) was measured by asking participants what the chances were that they would ever get HIV. Multivariable logistic regression was used to measure the association between actual and perceived HIV risk.ResultsOne hundred and fifty HIV-negative MSM were recruited (median age 44.5 years [IQR 37–50 years]). Twenty percent of MSM perceived their HIV risk to be high. The odds of having a high perceived risk was significantly higher in those with high actual HIV risk indicated by low condom use with an HIV-positive regular partner compared to those with low actual HIV risk indicated by high condom use with an HIV-positive regular partner (Odds Ratio (OR) 18.33, 95 % confidence interval (CI) 1.65–203.45). Older age was associated with lower perceived risk but only age 40–49 compared to less than 30 was statistically significant (OR 0.12, 95 % CI 0.016–0.86). The odds of having high perceived risk was significantly associated with men who used poppers in the previous 6 months compared to those who did not use poppers (OR 5.64, 95 % CI 1.20–26.48).ConclusionsPerceived HIV risk increased significantly as condom use with an HIV-positive regular partner decreased. However, perceived HIV risk was not associated with condom use with casual partners or HIV unknown status regular partners, even though these behaviours could be considered risky. The relationship between perceived and actual risk in HIV studies is complex and has implications on how health care workers address the issue of risky sexual behaviour and perceived risk.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-2859-6) contains supplementary material, which is available to authorized users.

Beyond Condoms: Risk Reduction Strategies Among Gay, Bisexual, and Other Men Who Have Sex With MenReceiving Rapid HIV Testing in Montreal, Canada.

Gay, bisexual, and other men who have sex with men (MSM) have adapted their sexual practices over the course of the HIV/AIDS epidemic based on available data and knowledge about HIV. This study sought to identify and compare patterns in condom use among gay, bisexual, and other MSM who were tested for HIV at a community-based testing site in Montreal, Canada. Results showed that while study participants use condoms to a certain extent with HIV-positive partners and partners of unknown HIV status, they also make use of various other strategies such as adjusting to a partner’s presumed or known HIV status and viral load, avoiding certain types of partners, taking PEP, and getting tested for HIV. These findings suggest that MSM who use condoms less systematically are not necessarily taking fewer precautions but may instead be combining or replacing condom use with other approaches to risk reduction.

HIV providers’ likelihood to prescribe pre-exposure prophylaxis (PrEP) for HIV prevention differs by patient type: a short report

ABSTRACTPre-exposure prophylaxis (PrEP), the antiretroviral treatment regimen for HIV-negative people at high risk of acquiring HIV, has demonstrated efficacy across clinical trials in several patient populations. The Centers for Disease Control (CDC) have released detailed guidelines to aid providers in prescribing PrEP for their high-risk patients, including men who have sex with men (MSM), high-risk heterosexuals, and injection drug users (IDUs). Given that much attention in PrEP has focused on MSM patients, the present study used an online survey to assess factors involved in HIV care providers’ (n = 363) decisions about prescribing PrEP, along with their willingness to prescribe PrEP to patients from various risk populations (e.g., MSM, heterosexuals, IDUs). The efficacy of PrEP was an important factor in providers' decisions about prescribing PrEP, as were considerations about patients’ adherence to the regimen, regular follow-up for care, and medication costs. This survey's findings also suggest that providers’ willingness to prescribe PrEP varies by patient group, with providers most willing to initiate the regimen with MSM who have an HIV-positive partner, and least willing to prescribe to high-risk heterosexuals or IDUs. In the context of the current CDC recommendations for PrEP that include MSM, heterosexuals, and IDUs, examining providers’ rationales for and barriers against supporting this HIV prevention strategy across patient groups merits further attention.

Seeking sex partners through the internet and mobile phone applications among men who have sex with men in Taiwan

ABSTRACTIt has become popular for men who have sex with men (MSM) to use mobile-phone geosocial networking applications (mobile apps) to find sex partners. A cross-sectional online survey was conducted in Taiwan to compare the sexual and substance-use behaviors of MSM seeking sex partners through the internet and mobile apps. Of the 1060 participants, 65.8% used the internet via computer and 37.7% used a mobile app to find sexual partners, while 30.3% used recreational drugs or alcohol in the previous 6 months. MSM who exclusively used mobile apps to seek sex partners were significantly more likely than MSM seeking sex via computer to be older, to have used recreational drugs or alcohol, and to have sex with HIV-positive partners. Additionally, using mobile apps to seek sex partners was significantly associated with having sex with online partners through either mobile apps or computer-based internet use (adjusted odds ratio (AOR), 7.12 [3.87–13.11]), self-reporting as HIV-positive (AOR, 2.24 [1.12–4.12]), using recreational drugs (AOR, 1.67 [1.21–2.32]), having disclosed HIV status to sexual partners (AOR, 1.44 [1.03–2.02]), and having sex with HIV-positive partners (AOR, 1.81 [1.06–3.10]). In conclusion, the mobile apps may serve as a feasible platform for HIV-positive MSM to find other HIV-positive partners.

Willingness to Act upon Beliefs about 'Treatment as Prevention' among Australian Gay and Bisexual Men.

HIV ‘treatment as prevention’ (TasP) is highly effective in reducing HIV transmission in serodiscordant couples. There has been little examination of gay and bisexual men’s attitudes towards TasP, particularly regarding men’s willingness to act on beliefs about TasP. We conducted an online cross-sectional survey of Australian men in late 2012 to investigate knowledge and beliefs about new developments in HIV prevention. Amongst 839 men (mean age 39.5 years), men tended to disagree that TasP was sufficiently effective to justify reduced condom use, although HIV-positive men had more favourable attitudes. Only a minority of men were aware of any evidence for TasP; and one-quarter incorrectly believed that evidence for the effectiveness of TasP already existed for the homosexual population. One-fifth (20.5%) of men reported that they would be willing to have condomless anal intercourse with an opposite-status sexual partner when the HIV-positive partner was taking HIV treatments. Factors independently associated with such willingness were: HIV-positive serostatus, reporting any serodiscordant or serononconcordant condomless anal intercourse with a regular male partner in the previous six months, reporting any condomless anal intercourse with a casual male partner in the previous six months, and having greater beliefs in the effectiveness of TasP. This indicated that the men most willing to rely on TasP to prevent transmission were already engaging in higher risk practices. Biomedical HIV prevention represents a rapidly changing environment with new research as well as community and policy responses emerging at a fast pace. For men with serodiscordant sexual partners to successfully apply TasP to reducing transmission risk, more support and education is needed to enable better utilisation of TasP in specific relational and sexual contexts.

What do we know about the cost–effectiveness of HIV preexposure prophylaxis, and is it affordable?

The WHO recommends preexposure prophylaxis (PrEP) in populations at substantial risk of HIV. Despite a number of randomized controlled trials demonstrating its efficacy, and several ongoing implementation projects, PrEP is currently only available in a few countries. Modelling studies can provide useful insights into the long-term impact of introducing PrEP in different subgroups of the population. The review summarizes studies that either evaluated the cost-effectiveness or the cost of introducing PrEP, focusing on seven published in the last year. These studies used a number of different types of models and investigated the introduction of PrEP in different settings. Among men having sex with men (MSM) in North America, PrEP ranged from being cost-saving (while benefiting population health) to costing US $160,000/quality-adjusted life-year gained. Among heterosexual sero-different couples, it varied from around US $5000 to US $10,000/disability-adjusted life-year averted, when PrEP was used until 6 or 12 months after the HIV-positive partner had initiated antiretroviral therapy (ART) in, respectively, Uganda and South Africa. Future cost-effectiveness studies of PrEP should consider the HIV incidence, the level of uptake, the effect of its introduction on alternative prevention approaches, and the budget impact of rolling it out.

Views of HIV-negative partners in heterosexual serodiscordant relationships regarding HIV pre-exposure prophylaxis: a qualitative study.

Background: Pre-exposure prophylaxis (PrEP) may be an effective option for HIV prevention among heterosexual serodiscordant couples. However, there are knowledge gaps in social research about PrEP in heterosexual serodiscordant relationships, including motivations and barriers to its use and possible impacts of PrEP uptake on the sexual practices of these couples. The aim of this study was to explore the views of HIV-negative men and women in stable serodiscordant heterosexual relationships about the possible use of PrEP. Methods: Semi-structured interviews were used to understand participants' views on the use of PrEP. Interviews were conducted face-to-face or by telephone and transcribed verbatim for thematic analysis. Results: In total, 13 HIV-negative partners were interviewed; six men and seven women. Participants demonstrated a high interest in the use of PrEP for conception. PrEP was also considered an option for general HIV prevention, although men saw more benefits for this use than women. Participants' main concerns around PrEP usage were about cost, efficacy, daily adherence and side-effects. HIV-positive partner support is likely to play a central role for PrEP uptake and adherence. Conclusions: This study is one of the first studies to explore the views of HIV-negative heterosexual partners in serodiscordant relationships around the use of PrEP while trying to conceive, as well as for general HIV prevention. These study results provide new insights for the further development of guidelines governing the use of PrEP for serodiscordant couples.

Efficient Identification of HIV Serodiscordant Couples by Existing HIV Testing Programs in South Brazil.

ObjectiveTo examine the feasibility of identifying HIV negative at risk individuals in HIV serodiscordant couples, during voluntary HIV testing in South Brazil.MethodsWe surveyed HIV testers at 4 public testing sites in Rio Grande do Sul. We obtained information on risk behaviors and sexual partnerships. HIV testing and testing for recent infection were performed; HIV prevalence and risk behaviors were assessed among subjects who reported having a steady partner who was HIV positive (serodiscordant group) and compared with the general testing population.ResultsAmong 3100 patients, 490 (15.8%) reported being in a steady relationship with an HIV positive partner. New HIV infections were diagnosed in 23% of the serodiscordant group (vs. 13% in the general population, p = 0.01); among newly positive subjects, recent HIV infections were more frequent (23/86, 26.7%) among testers with positive partners than among the general testing group (52/334; 15.6%; p = 0.016). Less than half of the serodiscordant testers reported having used a condom during the last sexual intercourse with their HIV-positive partner. Participants with inconsistent condom use with steady partner were four times more likely to test positive for HIV compared to those who reported always using condoms with the steady partner (OR: 4.2; 95% CI: 2.3 to 7.5).ConclusionIt is highly feasible to identify large numbers of HIV susceptible individuals who are in HIV serodiscordant relationships in South Brazil testing sites. Condom use within HIV serodiscordant couples is low in this setting, suggesting urgent need for biomedical prevention strategies to reduce HIV transmission.

Sex and secrecy: How HIV-status disclosure affects safe sex among HIV-positive adolescents

HIV-positive adolescents who engage in unsafe sex are at heightened risk for transmitting or re-acquiring HIV. Disclosure of HIV-status to sexual partners may impact on condom use, but no study has explored the effects of (i) adolescent knowledge of one's HIV-status, (ii) knowledge of partner status and (iii) disclosure to partners, on safer sex behaviour. This study aimed to identify whether knowledge of HIV-status by HIV-positive adolescents and partners was associated with safer sex. Eight fifty eight HIV-positive adolescents (10–19 years old, 52% female, 68.1% vertically infected) who had ever initiated antiretroviral treatment in 41 health facilities in the Eastern Cape, South Africa, were interviewed using standardised questionnaires. Quantitative analyses used multivariate logistic regressions, controlling for confounders. Qualitative research included interviews, focus group discussions and observations with 43 HIV-positive teenagers and their healthcare workers. N = 128 (14.9%) of the total sample had ever had sex, while N = 109 (85.1%) of sexually active adolescents had boy/girlfriend. In total, 68.1% of the sample knew their status, 41.5% of those who were sexually active and in relationships knew their partner's status, and 35.5% had disclosed to their partners. For adolescents, knowing one's status was associated with safer sex (OR = 4.355, CI 1.085–17.474, p = .038). Neither knowing their partner's status, nor disclosing one's HIV-status to a partner, were associated with safer sex. HIV-positive adolescents feared rejection, stigma and public exposure if disclosing to sexual and romantic partners. Counselling by healthcare workers for HIV-positive adolescents focused on benefits of disclosure, but did not address the fears and risks associated with disclosure. These findings challenge assumptions that disclosure is automatically protective in sexual and romantic relationships for HIV-positive adolescents, who may be ill-equipped to negotiate safer sex. There is a pressing need for effective interventions that mitigate the risks of disclosure and provide HIV-positive adolescents with skills to engage in safe sex.

The need to know: HIV status disclosure expectations and practices among non-HIV-positive gay and bisexual men in Australia

Although there is evidence of increasing overall rates of HIV status disclosure among gay and bisexual men, little is known about men's disclosure expectations and practices. In this study, we investigate the importance non-HIV-positive men in Australia vest in knowing the HIV status of their sexual partners, and the extent to which they restrict sex to partners of the same HIV status, and their HIV disclosure expectations. Data were collected through a national, online self-report survey. Of the 1044 men included in the study, 914 were HIV negative and 130 were untested. Participants completed the assessment of socio-demographic characteristics, HIV status preferences, and disclosure expectations and practices. Participants also completed reliable multi-item measures of perceived risk of HIV transmission, expressed HIV-related stigma, and engagement with the gay community and the community of people living with HIV. A quarter (25.9%) of participants wanted to know the HIV status of all sexual partners, and one-third (37.2%) restricted sex to partners of similar HIV status. Three quarters (76.3%) expected HIV-positive partners to disclosure their HIV status before sex, compared to 41.6% who expected HIV-negative men to disclose their HIV status. Less than half (41.7%) of participants reported that they consistently disclosed their HIV status to sexual partners. Multivariate linear regression analysis identified various covariates of disclosure expectations and practices, in particular of disclosure expectations regarding HIV-positive men. Men who expected HIV-positive partners to disclose their HIV status before sex more often lived outside capital cities, were less educated, were less likely to identify as gay, perceived more risk of HIV transmission from a range of sexual practices, were less engaged with the community of people living with HIV, and expressed more stigma towards HIV-positive people. These findings suggest that an HIV-status divide is emerging or already exists among gay men in Australia. HIV-negative and untested men who are most likely to sexually exclude HIV-positive men are less connected to the HIV epidemic and less educated about HIV risk and prevention.

From Their Voices: Barriers to HIV Testing among Black Men Who Have Sex with Men Remain.

Background: HIV testing continues to be a major priority for addressing the epidemic among young Black men who have sex with men (BMSM). Methods: This study explored barriers to HIV testing uptake, and recommendations for motivating HIV testing uptake among Black men who have sex with men (BMSM) aged 18 to 30. BMSM (N = 36) were recruited through flyers and social media for six focus groups. Results: From the perspectives and experiences of young BMSM, participants recommended that information be included in HIV testing messages that would help young BMSM do self HIV-risk appraisals. Particularly, participants recommended that more knowledge about Pre-Exposure Prophylaxis (PrEP) and the role of PrEP in safer-sex practices be provided. This information is important to help those untested, or who infrequently test, better understand their risk and need for testing. Likewise, participants recommended that more information about a person being undetectable and the risk of condomless sex with an HIV negative sex partner; this information will be helpful for both the HIV negative and HIV positive sex partner for making safer sex decisions. Participants also recommended that interventions should focus on more than drug use as risk; the risk posed by the use of alcohol before and during sex deserves attention among young BMSM. Conclusions: These findings may inform new HIV testing interventions being tailored for young BMSM. The interventions should also consider revisiting street-based peer-outreach approaches for those young BMSM with limited access to social media campaigns due to limited access or infrequent use of social media.

Increasing incidence of recent hepatitis C virus infection among persons seeking voluntary counselling and testing for HIV and sexually transmitted infections in Taiwan

ObjectivesThe incidence of hepatitis C virus (HCV) infection among HIV-negative men who have sex with men (MSM) is rarely investigated in the Asia-Pacific region. We aimed to estimate the incidence...

Modelling the impact and cost-effectiveness of combination prevention amongst HIV serodiscordant couples in Nigeria.

Objective:To estimate the impact and cost-effectiveness of treatment as prevention (TasP), pre-exposure prophylaxis (PrEP) and condom promotion for serodiscordant couples in Nigeria.Design:Mathematical and cost modelling.Methods:A deterministic model of HIV-1 transmission within a cohort of serodiscordant couples and to/from external partners was parameterized using data from Nigeria and other African settings. The impact and cost-effectiveness were estimated for condom promotion, PrEP and/or TasP, compared with a baseline where antiretroviral therapy (ART) was offered according to 2010 national guidelines (CD4+ <350 cells/μl) to all HIV-positive partners. The impact was additionally compared with a baseline of current ART coverage (35% of those with CD4+ <350 cells/μl). Full costs (in US $2012) of programme introduction and implementation were estimated from a provider perspective.Results:Substantial benefits came from scaling up ART to all HIV-positive partners according to 2010 national guidelines, with additional smaller benefits of providing TasP, PrEP or condom promotion. Compared with a baseline of offering ART to all HIV-positive partners at the 2010 national guidelines, condom promotion was the most cost-effective strategy [US $1206/disability-adjusted-life-year (DALY)], the next most cost-effective intervention was to additionally give TasP to HIV-positive partners (incremental cost-effectiveness ratio US $1607/DALY), followed by additionally giving PrEP to HIV-negative partners until their HIV-positive partners initiate ART (US $7870/DALY). When impact was measured in terms of infections averted, PrEP with condom promotion prevented double the number of infections as condom promotion alone.Conclusions:The first priority intervention for serodiscordant couples in Nigeria should be scaled up ART access for HIV-positive partners. Subsequent incremental benefits are greatest with condom promotion and TasP, followed by PrEP.

HIV Serosorting, Status Disclosure, and Strategic Positioning Among Highly Sexually Active Gay and Bisexual Men.

Researchers have identified harm reduction strategies that gay, bisexual, and other men who have sex with men (GBMSM) use to reduce HIV transmission--including serosorting, status disclosure, and strategic positioning. We report on patterns of these behaviors among 376 highly sexually active (i.e., 9+partners, <90 days) GBMSM: mean age of 37, 49.5% men of color, 87.8% gay identified, 57.5% college educated. We found evidence that many men engaged in serosorting, status disclosure, and strategic positioning; however, rates varied based on the participant's HIV status. HIV-positive and HIV-negative men both engaged in sex with men of similar status more often than they engaged in sex with men known to be a different HIV status (i.e., serosorting). However, HIV-negative men disclosed their HIV-status with about half of their partners, whereas HIV-positive participants disclosed with only about one-third. With regard to strategic positioning, HIV-positive participants were the receptive partner about half the time with their HIV-negative partners and with their HIV-positive partners. In contrast, strategic positioning was very common among HIV-negative participants-they rarely bottomed with HIV-positive partners, bottomed about one-third of the time with status-unknown partners, and 42% of the time (on average) with HIV-negative partners. Highly sexually active GBMSM are a critical population in which to both investigate HIV prevention strategies as well as develop effective intervention programs. Providers and clinicians might be well served to include a wide range of behavioral harm reduction strategies in addition to condom use and biomedical approaches to reduce onward HIV transmission.

Sexual networks, partnership mixing, and the female-to-male ratio of HIV infections in generalized epidemics

Background: Empirical estimates of the female-to-male ratio of infections in generalized HIV epidemics in sub-Saharan Africa range from 1.31 in Zambia to 2.21 in Ivory Coast. Inequalities in the gender ratio of infections can arise because of differences in exposure (to HIV-positive partners), susceptibility (given exposure), and survival (once infected). Differences in susceptibility have to date received most attention, but neither the relatively high gender ratio of infections nor the heterogeneity in empirical estimates is fully understood. Objective: Demonstrate the relevance of partnership network attributes and sexual mixing patterns to gender differences in the exposure to HIV-positive partners and the gender ratio of infections. Methods: Agent-based simulation model built in NetLogo. Results: The female-to-male ratio of infections predicted by our model ranges from 1.13 to 1.75. Gender-asymmetric partnership concurrency, rapid partnership turnover, elevated partnership dissolution in female-positive serodiscordant couples, and lower partnership re-entry rates among HIV-positive women can produce (substantial) differences in the gender ratio of infections. Coital dilution and serosorting have modest moderating effects. Conclusions: Partnership network attributes and sexual mixing patterns can have a considerable effect on the gender ratio of HIV infections. We need to look beyond individual behavior and gender differences in biological susceptibility if we are to fully understand, and remedy, gender inequalities in HIV infection in generalized epidemics.

O20.3 Hiv transmission in male serodiscordant couples in australia, thailand and brazil

Background Numerous prospective studies have demonstrated that HIV transmission is greatly reduced in heterosexual HIV serodiscordant couples when the HIV-positive partner (HPP) is receiving combination anti-retroviral therapy (cART) with undetectable viral load (UVL). Comparable data in homosexual male serodiscordant couples (HM-SDC) are extremely limited. We report a pre-specified interim analysis of the relationship between UVL and HIV transmission in the Opposites Attract observational cohort study of HM-SDC in Australia, Bangkok and Rio de Janeiro. Methods HM-SDC reporting regular anal intercourse with each other were recruited through clinical sites. Detailed information on sexual risk behaviours was collected at each visit from the HIV-negative partner (HNP). HNPs were tested at baseline and follow-up for HIV antibodies and STIs (sexually transmitted infections), and HPPs for HIV viral load and STIs. Incidence rates were calculated per couple-year of follow-up (CYFU) using person-year methods, and stratified by whether different forms of condomless anal intercourse (CLAI) were reported. UVL was defined as Results By December 2014, 234 HM-SDC were enrolled: 135 from Australia, 52 from Bangkok and 47 from Rio de Janeiro. There were a total of 150.0 CYFU in 152 couples with at least one follow-up visit of whom 65 (42.8%) were in a non-monogamous relationship. At baseline, 84.2% of HPPs were on cART and in total 82.9% had UVL. STI prevalence was 11.2% in HPPs and 6.6% in HNPs. There were 90.8 CYFU in periods where CLAI was reported with a total of 5,905 acts of CLAI in 88 couples. There were no linked HIV transmissions. The upper limit of the 95% CI of the transmission rate was 4.06/100 CYFU for periods in which CLAI was reported, and 6.46/100 CYFU for periods in which receptive CLAI was reported. Conclusions There were no linked HIV transmissions in 150 CYFU in these HM-SDC, despite close to 6,000 acts of CLAI. The upper confidence limit of the transmission rate during follow-up in periods during which CLAI was occurring was 4.06/100 CYFU. These data add to emerging evidence that the rate of HIV transmission in HM-SDC is very low when the HIV-positive partner is on ART. Further follow-up of a larger sample size is required to accurately delineate any residual risk.

P11.05 Proportion of hiv and sexually transmitted infection (sti) cases among men who have sex with men (msm) attributable to serosorting

Introduction The contribution of serosorting to HIV/STI disease burden among MSM is unknown. Methods The study used data collected as part of routine care at an STD clinic 2002–2013 or a community-based HIV/STD testing centre 2004–2013 in Seattle, Washington. Data included men’s condom use for anal sex with HIV-positive, negative and unknown-status partners in the prior 12 months. We defined three mutually-exclusive behavioural categories: serosorting (condomless anal intercourse [CAI] only with HIV-concordant partners); non-concordant CAI (any CAI with HIV-discordant/unknown-status partners; [NCCAI]); and no CAI (consistent condom use or no AI). We estimated adjusted relative risks (aRR) between sexual behaviour and HIV/STI, and calculated the population attributable risk (PAR%) as the proportion of HIV/STI cases attributable to serosorting (assuming serosorters would have otherwise consistently used condoms) and the population prevented fraction (PF) as the proportion of hypothetical HIV/STI cases averted by serosorting (assuming serosorters would have otherwise had NCCAI). Results Behavioural data were complete for 49,912 visits; 91% (n = 45,220) were among self-reported HIV-negative MSM. Overall, serosorting was reported by 35% and 38% of HIV-negative and positive MSM, respectively. Compared to men reporting no CAI, HIV-negative serosorters had a significantly higher risk of HIV (aRR = 2.0), syphilis (aRR = 2.0), urethral gonorrhoea/chlamydia (GC/CT) (aRR = 1.5) and rectal GC/CT (aRR = 1.7). The proportion of HIV/STI cases attributable to serosorting (PAR%) were: HIV (15.3%); syphilis (16.9%); urethral GC/CT (11.9%); rectal GC/CT (19.3%). Serosorters had a significantly lower risk of HIV (aRR = 0.53) and syphilis (aRR = 0.76) compared to men reporting NCCAI; the proportion of HIV and syphilis cases averted by serosorting (PF) were 14.6% and 8.3%, respectively. Among HIV-positive MSM, syphilis risk was significantly higher for serosorters compared to consistent condom users (aRR = 1.4; PAR% = 12.1%). Conclusion These data suggest that serosorting is responsible for, but also prevents, 15% of HIV cases among MSM (PAR% = 15.3% and PF = 14.6%), depending on the behaviour it replaces. Disclosure of interest statement No pharmaceutical grants were received in the development of this study.

Sexual Behaviors and Transmission Risks Among People Living with HIV: Beliefs, Perceptions, and Challenges to Using Treatments as Prevention.

Antiretroviral therapy (ART) improves the health of people living with HIV and can reduce infectiousness, preventing HIV transmission. The potential preventive benefits of ART are undermined by beliefs that it is safe to have condomless sex when viral load is below levels of detection (infectiousness beliefs and risk perceptions). In this study, we hypothesized that infectiousness beliefs and HIV transmission risk perceptions would prospectively predict people living with HIV engaging in more condomless sex with HIV-negative and unknown HIV status sex partners. Sexually active HIV-positive men (n=538, 76%) and women (n=166, 24%) completed computerized interviews of sexually transmitted infection (STI) symptoms and diagnoses, unannounced pill counts for medication adherence, medical chart-abstracted HIV viral load, and 28 daily cell-phone-delivered prospective sexual behavior assessments. Results showed that a total of 313 (44%) participants had engaged in condomless sex with HIV-negative/unknown status sex partners, and these individuals demonstrated higher rates of STI symptoms and diagnoses. Two-thirds of participants who had condomless sex with HIV-negative/unknown status partners had not disclosed their HIV status. Multivariable logistic regression models showed that beliefs regarding viral load and HIV infectiousness and perceptions of lower risk of HIV transmission resulting from HIV viral suppression predicted condomless sex with potentially uninfected partners over and above sex behaviors with HIV-positive partners and STI symptoms/diagnoses. Interventions that address HIV status disclosure and aggressively treat STI in sexually active people living with HIV should routinely accompany the use of HIV treatments as prevention.

Factors associated with sexual risk behaviors with non-steady partners and lack of recent HIV testing among German men who have sex with men in steady relationships: results from a cross-sectional internet survey.

BackgroundRecent evidence suggests that the majority of HIV transmissions among men who have sex with men (MSM) occur between steady partners. We sought to determine factors associated with HIV transmission risks in steady partnerships.MethodsData is from the German cross-sectional 2013 Gay Men and AIDS survey. The study population was HIV-negative or untested men reporting a steady partnership and at least one non-steady anal sex partner in the previous year. Bivariate and multivariate logistic regression was used to determine which of several independent variables best predicted both unprotected anal intercourse (UAI) with a non-steady partner and lack of HIV testing in the past year (high-risk outcome group).ResultsThe study population consisted of 1731 men. Among individuals in the outcome group (n = 271), 67 % reported UAI with a non-steady partner of unknown status and 9 % reported UAI with a non-steady HIV-positive partner in the past 12 months; 55 % considered themselves to be at low risk for HIV acquisition. In multivariate analyses (n = 1304), participants were statistically more likely to belong to the outcome group if they reported UAI with their steady partner in the past year (OR = 2.21), did not know their steady partner’s HIV status (OR = 1.98), or agreed that condoms were disruptive during sex (OR = 3.82 (strongly agree), OR = 2.19 (agree)). Participants were less likely to belong to the outcome group if they were out to their primary doctor (OR = 0.54), were well-educated about post-exposure prophylaxis (OR = 0.46), had sought information on HIV in the past year and kept condoms in an accessible place (OR = 0.20), or believed that insisting on condoms would lead partners to assume they were HIV-negative (OR = 0.20). Participants in the outcome group were more likely to say they would use HIV home tests (OR = 1.58) or pre-exposure prophylaxis (OR = 2.11).ConclusionsBased on our results, we reflect on HIV prevention measures that should be improved in order to better target behaviors that may lead to HIV transmission between MSM in steady relationships. In particular, we highlight the need for multifaceted interventions focusing not only on members of the at-risk community themselves, but on communities as a whole.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-015-1987-8) contains supplementary material, which is available to authorized users.

Detection of HIV-1-specific T-cell immune responses in highly HIV-exposed uninfected individuals by in-vitro dendritic cell co-culture.

Although virus-specific responses are rarely detected by conventional approaches, we report here the detection of T-cell responses in HIV-exposed seronegative (HESN) patients by two distinct assays. HIV-specific T-cell responses were analyzed by enzyme-linked immunospot in peripheral blood mononuclear cells from HESN patients after a 48-h co-culture with boosted dendritic cells. Additionally, a boosted flow cytometry approach was used to capture antiviral T-cell responses. Host genetic factors and T-cell activation were also analyzed to assess their implication on HIV exposure. Of the 45 HESN individuals tested, up to 11 (24.4%) showed at least one response to peptide pools covering HIV Gag and Nef. A positive correlation was observed between the intensity (P = 0.0022) and magnitude (P = 0.0174) of the response detected in the HESN, and the viral load of the HIV-positive partner. Moreover, the result from the boosted flow and cytomix analyses showed a dominant Th1-like response pattern against HIV antigens, especially in CD8 T-cell populations. The combined use of our boosted dendritic cell technique with a boosted flow cytometric approach allows us both to detect specific HIV-positive responses in a higher percentage of HESN patients and to define specific effector function profiles. This study contributes to a better understanding of resistance to HIV infection.