Available evidence does not support serosorting as an HIV risk reduction strategy

Increase in the overall level of protected anal sex in men who have sex with men in France: results from the repeated cross-sectional survey Rapport au Sexe, France, 2017-2019

This study measures the evolution in the overall level of protection against HIV by men who have sex with men (MSM) in France. Using data from the 2017 and 2019 editions of Rapport au Sexe - an online survey - we compared the use of HIV prevention tools by MSM during their most recent anal intercourse (MRAI) with a casual male partner. We developed a classification with five categories ordered according to the effectiveness of each tool method in reducing the risk of acquiring HIV: Treatment as prevention (TasP), Pre-exposure prophylaxis (PrEP), exclusive condom use, Post-exposure prophylaxis (PEP) or nothing (i.e., no tool used). The percentage of MSM who did not use any prevention tool decreased from 25.9% in 2017 to 23.5% in 2019 (aOR [95%CI] = 0.9 [0.8-0.9]). The proportion of MSM who took PrEP during the MRAI increased from 5.4% in 2017 to 14.0% in 2019 (aOR [95%CI] = 2.9[2.5-3.3]). The proportion of MSM who used condoms exclusively decreased from 67.5% in 2017 to 61.3% in 2019 (aOR [95%CI] = 0.8 [0.7-0.8]). We observed an increase in the rate of protected anal sex, and a decrease in the rate of condom use. The implementation of PrEP may be one of the main driving forces behind these changes.

Randomised controlled trial of a sexual risk reduction intervention for STI prevention among men who have sex with men in the USA

OBJECTIVES

Novel interventions to address sexual risk taking and slow rates of STIs are urgently needed, in particular among black men who have sex with men (MSM) in the USA. Serosorting, or limiting condomless sex acts to partners of the same HIV status, is commonly practised among MSM, yet can lead to STI and remains largely unaddressed by public health agencies.

METHODS

A two-arm, randomised controlled trial was conducted from 2012 to 2015. This trial assessed the effects of a single-session, sexual partner selection and risk decision intervention (experimental arm) versus a single-session, Centers for Disease Control and Prevention-based, sexual risk reduction intervention (control arm) on psychosocial measures, sexual risk taking and STI.

RESULTS

At study follow-ups, multiple beneficial changes were observed on sexual risk beliefs measures (ie, changes in serosorting and condom use beliefs, and HIV risk perceptions) and sexual risk taking among the experimental arm relative to the control arm. Overall main effects, however, of the intervention on STI outcomes on year-long follow-ups were non-significant. There was evidence for short-term effects on STI outcomes, and self-report of multiple STIs and STI symptoms demonstrated positive effects over the follow-up period.

CONCLUSIONS

Brief interventions to address sexual risk taking can result in short-term beneficial outcomes and can be incorporated into currently existing infrastructure at healthcare agencies. Additional intervention will be necessary for demonstrating long-term results.

TRIAL REGISTRATION NUMBER

NCT02128594.

Trends in Serosorting and the Association With HIV/STI Risk Over Time Among Men Who Have Sex With Men

BACKGROUND

Serosorting among men who have sex with men (MSM) is common, but recent data to describe trends in serosorting are limited. How serosorting affects population-level trends in HIV and other sexually transmitted infection (STI) risk is largely unknown.

METHODS

We collected data as part of routine care from MSM attending a sexually transmitted disease clinic (2002-2013) and a community-based HIV/sexually transmitted disease testing center (2004-2013) in Seattle, WA. MSM were asked about condom use with HIV-positive, HIV-negative, and unknown-status partners in the prior 12 months. We classified behaviors into 4 mutually exclusive categories: no anal intercourse (AI); consistent condom use (always used condoms for AI); serosorting [condom-less anal intercourse (CAI) only with HIV-concordant partners]; and nonconcordant CAI (CAI with HIV-discordant/unknown-status partners; NCCAI).

RESULTS

Behavioral data were complete for 49,912 clinic visits. Serosorting increased significantly among both HIV-positive and HIV-negative men over the study period. This increase in serosorting was concurrent with a decrease in NCCAI among HIV-negative MSM, but a decrease in consistent condom use among HIV-positive MSM. Adjusting for time since last negative HIV test, the risk of testing HIV positive during the study period decreased among MSM who reported NCCAI (7.1%-2.8%; P= 0.02), serosorting (2.4%-1.3%; P = 0.17), and no CAI (1.5%-0.7%; P = 0.01). Serosorting was associated with a 47% lower risk of testing HIV positive compared with NCCAI (adjusted prevalence ratio = 0.53; 95% confidence interval: 0.45 to 0.62).

CONCLUSIONS

Between 2002 and 2013, serosorting increased and NCCAI decreased among Seattle MSM. These changes paralleled a decline in HIV test positivity among MSM.

HIV-Negative Partnered Men's Willingness to Use Non-Occupational Post-Exposure Prophylaxis and Associated Factors in a U.S. Sample of HIV-Negative and HIV-Discordant Male Couples

PURPOSE

Non-occupational post-exposure prophylaxis (nPEP) is an underutilized biomedical option for HIV prevention. Few studies have assessed male couples' knowledge of and willingness to use nPEP.

METHODS

Cross-sectional dyadic data from 275 HIV-negative and 58 HIV-discordant male couples were used to describe HIV-negative, partnered men's awareness and willingness to use nPEP, and factors associated with their willingness to use nPEP. Data were analyzed with the use of multivariate multilevel modeling.

RESULTS

Less than a third of the men were aware of nPEP, yet 73% were very-to-extremely likely to use nPEP. Partnered men's willingness to use nPEP was positively associated with having an individual income less than $30,000 USD and serosorting within the relationship. Willingness to use nPEP was negatively associated with greater age difference between primary partners and with higher scores on measures of couples' investment in their relationship.

CONCLUSION

Efforts should be made to increase male couples' awareness of nPEP and how to access nPEP. Uptake of nPEP has the potential to help avert new HIV infections among male couples.

Sexual and prevention practices in men who have sex with men in the era of combination HIV prevention: results from the Presse Gays et Lesbiennes survey, France, 2011

To better understand the diversity of practices and behaviours to prevent HIV with casual partners, data from a large convenience sample of men who have sex with men (MSM) in France were categorised into different prevention profiles: no anal intercourse, consistent condom use during anal intercourse, risk-reduction practices (serosorting, seropositioning) and no discernible prevention practice (NDPP). Categories were applied to HIV-positive respondents with controlled (CI; n=672) and uncontrolled infection (UI; n=596), HIV-negative (n=4,734) and untested respondents (n=663). Consistent condom use was reported by 22% (n=148) of HIV-positive-CI respondents, 13% (n=79) of HIV-positives UI, 55% (2,603) of HIV-negatives, and 50% (n=329) of untested (p<0.001). Corresponding figures for NDPP were 45% (n=304), 55% (n=327), 21% (n=984) and 34% (n=227) (p<0.001). Logistic regressions showed that, regardless of respondents' serostatus, NDPP was associated with regularly frequenting dating websites, drug use, exposure to sperm during oral sex, and with HIV diagnosis after 2000 for HIV-positive respondents (CI and UI), with age <30 years for HIV-positive-CI, and with low education for HIV-negatives. Risk-taking remains high, despite implementation of risk-reduction practices. A global health approach should be central to prevention programmes for MSM, to include target behavioural intervention, promotion of condom use, and encouragement of regular HIV testing and early initiation of ART.

Conversation about Serostatus decreases risk of acquiring HIV: results from a case control study comparing MSM with recent HIV infection and HIV negative controls

Background

Data on knowledge, attitudes, behaviour and practices (KABP) of persons with recent HIV infection compared to controls with negative HIV test result provide information on current risk patterns and can help to re-focus HIV prevention strategies.

Methods

From March 2008 through May 2010, persons newly diagnosed with HIV (cases) and HIV-negative controls were recruited by physicians in Germany. To distinguish recent (< 5 months) from longstanding (> 5 months) infection, dried blood spots from people newly diagnosed with HIV were tested with the BED IgG-capture ELISA. Cases and controls completed a KABP-questionnaire. We compared cases with recent infection and controls among men having sex with men (MSM) regarding reported risk behaviour in the previous 6 months. To detect differences, unadjusted Odds Ratios (OR) were calculated and multivariate analysis was performed.

Results

Cases and controls did not differ in terms of knowledge on transmission risks, HIV testing frequency, partnership status, or regarding the frequency of any unprotected sex with partners known to be HIV-positive or assumed to be HIV-negative. Cases more often reported a shorter duration of partnership (< 6 months) with a primary partner than controls (OR = 3.9; p = 0.003) and indicated lower rates of condom use outside of primary relationships, with acquaintances (OR = 2.5; p = 0.01), and with persons met online (OR = 4.5; p = 0.04). Unprotected sex with persons of unknown HIV-serostatus was more often indicated by cases than controls (OR = 3.0; p = 0.003). Having a conversation about HIV serostatus before having sex was associated with a lower risk of infection (OR = 0.2; p = 0.01). In multivariate analysis “being always safe” (always using a condom when having sex in different situations outside of a relationship) and talking about serostatus before sex (OR = 0.23; p = 0.004; OR = 0.14; p = 0.014) were negatively associated with HIV- infection.

Conclusions

There were no significant differences regarding knowledge about HIV-transmission risks among cases and controls. Differences in risk behaviour were observed regarding unprotected sex with partners of unknown HIV-serostatus and duration of primary partnership at the time of diagnosis, suggesting some HIV-transmissions occurring in newly formed partnerships. The practice of discussing serostatus with prospective sex partners before engaging in sex seems to be protective for HIV-transmission.

Seroadaptation among men who have sex with men: emerging research themes

Seroadaptation describes a diverse set of potentially harm-reducing behaviors that use HIV status to inform sexual decision making. Men who have sex with men (MSM) in many settings adopt these practices, but their effectiveness at preventing HIV transmission is debated. Past modeling studies have demonstrated that serosorting is only effective at preventing HIV transmission when most men accurately know their HIV status, but additional modeling is needed to address the effectiveness of broader seroadaptive behaviors. The types of information withwhichMSMmake seroadaptive decisions is expanding to include viral load, treatment status, and HIV status based on home-use tests, and recent research has begun to examine the entire seroadaptive process, from an individual's intentions to seroadapt to their behaviors to their risk of acquiring or transmitting HIV and other STIs. More research is needed to craft clear public health messages about the risks and benefits of seroadaptive practices.

Men having sex with men serosorting with casual partners: who, how much, and what risk factors in Switzerland, 2007-2009

Background

Serosorting is practiced by men who have sex with men (MSM) to reduce human immunodeficiency virus (HIV) transmission. This study evaluates the prevalence of serosorting with casual partners, and analyses the characteristics and estimated numbers of serosorters in Switzerland 2007-2009.

Methods

Data were extracted from cross-sectional surveys conducted in 2007 and 2009 among self-selected MSM recruited online, through gay newspapers, and through gay organizations. Nested models were fitted to ascertain the appropriateness of pooling the datasets. Multiple logistic regression analysis was performed on pooled data to determine the association between serosorting and demographic, lifestyle-related, and health-related factors. Extrapolations were performed by applying proportions of various types of serosorters to Swiss population data collected in 2007.

Results

A significant and stable number of MSM (approximately 39% in 2007 and 2009) intentionally engage in serosorting with casual partners in Switzerland. Variables significantly associated with serosorting were: gay organization membership (aOR = 1.67), frequent internet use for sexual encounters (aOR = 1.71), having had a sexually transmitted infection (STI) at any time in the past 12 months (aOR = 1.70), HIV-positive status (aOR = 0.52), regularly frequenting sex-on-premises venues (aOR = 0.42), and unprotected anal intercourse (UAI) with partners of different or unknown HIV status in the past 12 months (aOR = 0.22). Approximately one-fifth of serosorters declared HIV negativity without being tested in the past 12 months; 15.8% reported not knowing their own HIV status.

Conclusion

The particular risk profile of serosorters having UAI with casual partners (multiple partners, STI history, and inadequate testing frequency) requires specific preventive interventions tailored to HIV status.

Evaluating immunologic response and clinical deterioration in treatment-naive patients initiating first-line therapies infected with HIV-1 CRF01_AE and subtype B

BACKGROUND

HIV-1 group M viruses diverge 25%-35% in envelope, important for viral attachment during infection, and 10%-15% in the pol region, under selection pressure from common antiretrovirals. In Asia, subtypes B and CRF01_AE are common genotypes. Our objectives were to determine whether clinical, immunological, or virological treatment responses differed by genotype in treatment-naive patients initiating first-line therapy.

METHODS

Prospectively collected longitudinal data from patients in Thailand, Hong Kong, Malaysia, Japan, Taiwan, and South Korea were provided for analysis. Covariates included demographics, hepatitis B and C coinfections, baseline CD4 T lymphocyte count, and plasma HIV-1 RNA levels. Clinical deterioration (a new diagnosis of Centers for Disease Control and Prevention category B/AIDS-defining illness or death) was assessed by proportional hazards models. Surrogate endpoints were 12-month change in CD4 cell count and virologic suppression post therapy, evaluated by linear and logistic regression, respectively.

RESULTS

Of 1105 patients, 1036 (93.8%) infected with CRF01_AE or subtype B were eligible for inclusion in clinical deterioration analyses and contributed 1546.7 person-years of follow-up (median: 413 days, interquartile range: 169-672 days). Patients >40 years demonstrated smaller immunological increases (P = 0.002) and higher risk of clinical deterioration (hazard ratio = 2.17; P = 0.008). Patients with baseline CD4 cell counts >200 cells per microliter had lower risk of clinical deterioration (hazard ratio = 0.373; P = 0.003). A total of 532 patients (48.1% of eligible) had CD4 counts available at baseline and 12 months post therapy for inclusion in immunolgic analyses. Patients infected with subtype B had larger increases in CD4 counts at 12 months (P = 0.024). A total of 530 patients (48.0% of eligible) were included in virological analyses with no differences in response found between genotypes.

CONCLUSIONS

Results suggest that patients infected with CRF01_AE have reduced immunologic response to therapy at 12 months, compared with subtype B-infected counterparts. Clinical deterioration was associated with low baseline CD4 counts and older age. The lack of differences in virologic outcomes suggests that all patients have opportunities for virological suppression.

Seroadaptation in a sample of very poor Los Angeles area men who have sex with men

Data from 635 very poor men who have sex with men (MSM) were used to identify seroadaptation with 1,102 male partners reported between 2005 and 2007 in Los Angeles as part of the Sexual Acquisition and Transmission of HIV Cooperative Agreement Program. The mean age of the sample was 41.7 years; 53 % had experienced homelessness in the past year. Condoms were reported in 51 % of sexual events involving anal intercourse. HIV seroconcordance was reported in 41 % of sexual partnerships among HIV-positive participants. HIV-positive men were more likely to have oral-only or unprotected receptive anal intercourse and less likely to have unprotected insertive anal intercourse with HIV-negative or unknown partners compared to HIV-positive partners. Even in the face of poverty, HIV-positive MSM report mitigating risks of HIV-transmission though seroadaptation in the context of modest rates of condom use.

Failure of serosorting to protect African American men who have sex with men from HIV infection

BACKGROUND

Serosorting is the practice of choosing sex partners or selectively using condoms based on a sex partner's perceived HIV status. The extent to which serosorting protects African American (AA) and Hispanic men who have sex with men (MSM) is unknown.

METHODS

We analyzed data collected from MSM sexually transmitted diseases clinic patients in Seattle, WA, 2001-2010. Men were asked about the HIV status of their anal sex partners in the prior year and about their condom use with partners by partner HIV status. We defined serosorters as MSM who had unprotected anal intercourse (UAI) only with partners of the same HIV status, and compared the risk of testing HIV positive among serosorters and men who reported having UAI with partners of opposite or unknown HIV status (ie, nonconcordant UAI). We used generalized estimating equations to evaluate the association of serosorting with testing HIV positive.

RESULTS

A total of 6694 MSM without a prior HIV diagnosis were tested during 13,657 visits; 274 men tested HIV positive. Serosorting was associated with a lower risk of testing HIV positive than nonconcordant UAI among white MSM (2.1 vs. 4.5%, odds ratio [OR]: 0.45, 95% confidence interval [CI]: 0.34-0.61), but not AA MSM (6.8 vs. 6.0%, OR: 1.1, 95% CI: 0.57-2.2). Among Hispanics, the risk of testing HIV positive was lower among serosorters than men engaging in nonconcordant UAI, though this was not significant (4.1 vs. 6.0%, OR: 0.67, 95% CI: 0.36-1.2).

CONCLUSIONS

In at least some AA MSM populations, serosorting does not seem to be protective against HIV infection.

Interaction of mathematical modeling and social and behavioral HIV/AIDS research

PURPOSE OF REVIEW

HIV is transmitted within complex biobehavioral systems. Mathematical modeling can provide insight to complex population-level outcomes of various behaviors measured at an individual level.

RECENT FINDINGS

HIV models in the social and behavioral sciences can be categorized in a number of ways; here, we consider two classes of applications common in the field generally, and in the past year in particular: those models that explore significant behavioral determinants of HIV disparities within and between populations; and those models that seek to evaluate the potential impact of specific social and behavioral interventions.

SUMMARY

We discuss two overarching issues we see in the field: the need to further systematize effectiveness models of behavioral interventions, and the need for increasing investigation of the use of behavioral data in epidemic models. We believe that a recent initiative by the National Institutes of Health will qualitatively change the relationships between epidemic modeling and sociobehavioral prevention research in the coming years.