Time location sampling in men who have sex with men in the HIV context: the importance of taking into account sampling weights and frequency of venue attendance

Community stigma, victimization, and coping strategies among gay, bisexual, and other cis-gender men who have sex with men in slum communities in Ghana. BSGH-003

BACKGROUND

Gay, bisexual, and cis-gender men who have sex with men (GBMSM) face severe consequences, especially within stigmatized environments. However, very little is known about the experiences of GBMSM living in slums in SSA and Ghana. This study investigates the experiences of stigma, victimization, and coping strategies and proposes some interventional approaches for combating stigma facing GBMSM in slum communities.

METHODS

We engaged GBMSM living in slums in two major Ghanaian cities. We used a time-location sampling and collected data through in-depth individual interviews. Two major themes emerged from the study: (1) insecurities and criminalization of GBMSM activity, and (2) GBMSM coping strategies.

RESULTS

Findings show GBMSM experienced negative attitudes from the community due to their sexual behavior/orientation. GBMSM also developed coping strategies to avert negative experiences, such as hiding their identities/behavior, avoiding gender non-conforming men, and having relationships with persons outside their communities.

CONCLUSION

We propose interventions such as HIV Education, Empathy, Empowerment, Acceptance, and Commitment Therapy as possible measures to improve the experiences of GBMSM living in Ghanaian slum communities.

Awareness and Willingness to use Condoms and Preexposure Prophylaxis among Gay, Bisexual, and Other Cisgendered Men who Have sex with men in Slum Communities in Ghana. BSGH-004

Introduction: Research has begun to examine human immunodeficiency virus (HIV) prevention strategies within the Ghanaian context. Still, little is known about specific populations such as gay, bisexual, and other cisgender men who have sex with men (GBMSM) living in slum communities. We studied HIV prevention strategies such as condoms and preexposure prophylaxis (PrEP) in slum communities and the awareness and willingness to use these choices among GBMSM. This qualitative study examines HIV prevention strategies, specifically examining PrEP and condom use behaviors among GBMSM in Ghana. Methods: We conducted in-depth face-to-face interviews among 12 GBMSM from slums in Accra and Kumasi cities in Ghana. Data were analyzed through a summative content analysis with multiple reviewers to develop codes. Data were collected from participants in January 2022. Results: We found the fear and perceived risk of infection were motivators for consistent condom use, especially during anal sex. GBMSM living with HIV receiving antiretroviral therapy were more inclined to use condoms. We found motivations for using PrEP were influenced by the type of sexual activity and a history of negative HIV status. Also, the barriers to PrEP for GBMSM included limited access to healthcare facilities and the distance to these facilities. Conclusions: To improve condom and PrEP access and uptake, we recommend addressing structural barriers by increasing the number of health facilities and implementing targeted interventions to address the lack of information on HIV awareness and prevention. Involving peer educators may also effectively promote HIV prevention strategies, especially in communities with limited access to healthcare such as slums. Overcoming these access constraints could significantly enhance awareness and prevention of HIV, leading to improved health outcomes for GBMSM living in slum communities.

Cost-effectiveness of hepatitis C virus test-and-treat and risk reduction strategies among men who have sex with men living with HIV in France

INTRODUCTION

Studies suggest that hepatitis C virus (HCV) micro-elimination is feasible among men who have sex with men (MSM) living with human immunodeficiency virus (HIV), through treatment-as-prevention and interventions aimed at reducing risk behaviours. However, their economic impact is poorly understood. The aim of this study was to assess the cost-effectiveness of HCV screening and risk reduction strategies in France.

METHODS

A compartmental deterministic mathematical model was developed to describe HCV disease transmission and progression among MSM living with HIV in France. We evaluated different combinations of HCV screening frequency (every 12, 6 or 3 months) and risk reduction strategies (targeting only high-risk or all MSM) from 2021 onwards. The model simulated the number of HCV infections, life-expectancy (LYs), quality-adjusted life-expectancy (QALYs), lifetime costs and incremental cost-effectiveness ratio (ICER) over a lifetime horizon (leading to an end of the simulation in 2065).

RESULTS

All strategies increased QALYs, compared with current practices, that is yearly HCV screening, with no risk reduction. A behavioural intervention resulting in a 20% risk reduction in the high-risk group, together with yearly screening, was the least expensive strategy, and, therefore, cost-saving compared to current practices. The ICER per QALY gained for the strategy combining risk reduction for the high-risk group with 6-month HCV screening, compared to risk reduction with yearly screening, was €61,389. It also prevented 398 new HCV infections between 2021 and 2065, with a cost per infection averted of €37,790. All other strategies were dominated (more expensive and less effective than some other available alternative) or not cost-effective (ICER per QALY gained > €100,000).

CONCLUSIONS

In the French context, current HCV screening practices without risk reduction among MSM living with HIV cannot be justified on economic grounds. Risk reduction interventions targeted to high-risk individuals-alongside screening either once or twice a year-could be cost-effective depending on the policymaker's willingness-to-pay.

Respondent-Driven Sampling: a Sampling Method for Hard-to-Reach Populations and Beyond

Purpose of Review

We provided an overview of sampling methods for hard-to-reach populations and guidance on implementing one of the most popular approaches: respondent-driven sampling (RDS).

Recent Findings

Limitations related to generating a sampling frame for marginalized populations can make them “hard-to-reach” when conducting population health research. Data analyzed from non-probability-based or convenience samples may produce estimates that are biased or not generalizable to the target population. In RDS and time-location sampling (TLS), factors that influence inclusion can be estimated and accounted for in an effort to generate representative samples. RDS is particularly equipped to reach the most hidden members of hard-to-reach populations.

Summary

TLS, RDS, or a combination can provide a rigorous method to identify and recruit samples from hard-to-reach populations and more generalizable estimates of population characteristics. Researchers interested in sampling hard-to-reach populations should expand their toolkits to include these methods.

HIV seroprevalence in five key populations in Europe: a systematic literature review, 2009 to 2019

Background

In Europe, HIV disproportionately affects men who have sex with men (MSM), people who inject drugs (PWID), prisoners, sex workers, and transgender people. Epidemiological data are primarily available from national HIV case surveillance systems that rarely capture information on sex work, gender identity or imprisonment. Surveillance of HIV prevalence in key populations often occurs as independent studies with no established mechanism for collating such information at the European level.

Aim

We assessed HIV prevalence in MSM, PWID, prisoners, sex workers, and transgender people in the 30 European Union/European Economic Area countries and the United Kingdom.

Methods

We conducted a systematic literature review of peer-reviewed studies published during 2009–19, by searching PubMed, Embase and the Cochrane Library. Data are presented in forest plots by country, as simple prevalence or pooled across multiple studies.

Results

Eighty-seven country- and population-specific studies were identified from 23 countries. The highest number of studies, and the largest variation in HIV prevalence, were identified for MSM, ranging from 2.4–29.0% (19 countries) and PWID, from 0.0–59.5% (13 countries). Prevalence ranged from 0.0–15.6% in prisoners (nine countries), 1.1–8.5% in sex workers (five countries) and was 10.9% in transgender people (one country). Individuals belonging to several key population groups had higher prevalence.

Conclusion

This review demonstrates that HIV prevalence is highly diverse across population groups and countries. People belonging to multiple key population groups are particularly vulnerable; however, more studies are needed, particularly for sex workers, transgender people and people with multiple risks.

Impact of test-and-treat and risk reduction strategies on HCV transmission among MSM living with HIV in France: a modelling approach

OBJECTIVE

Since the early 2000s, there has been an epidemic of HCV occurring among men who have sex with men (MSM) living with HIV, mainly associated with high-risk sexual and drug-related behaviours. Early HCV diagnosis and treatment, and behavioural risk-reduction, may be effective to eliminate HCV among MSM living with HIV.

DESIGN

We developed a deterministic dynamic compartmental model to simulate the impact of test-and-treat and risk-reduction strategies on HCV epidemic (particularly on incidence and prevalence) among MSM living with HIV in France. We accounted for HIV and HCV cascades of care, HCV natural history and heterogeneity in HCV risk behaviours. The model was calibrated to primary HCV incidence observed between 2014 and 2017 among MSM living with HIV in care (ANRS CO4-French hospital database on HIV (FHDH)).

RESULTS

With current French practices (annual HCV screening and immediate treatment), total HCV incidence would fall by 70%, from 0.82/100 person-years in 2015 to 0.24/100 person-years in 2030. It would decrease to 0.19/100 person-years in 2030 with more frequent screening and to 0.19 (0.12)/100 person-years in 2030 with a 20% (50%) risk-reduction. When combining screening every 3 months with a 50% risk-reduction, HCV incidence would be 0.11/100 person-years in 2030, allowing to get close to the WHO target (90% reduction from 2015 to 2030). Similarly, HCV prevalence would decrease from 2.79% in 2015 to 0.48% in 2030 (vs 0.71% with current practices).

CONCLUSION

Combining test-and-treat and risk-reduction strategies could have a marked impact on the HCV epidemic, paving the way to HCV elimination among MSM living with HIV.

Improving Underestimation of HIV Prevalence in Surveys Using Time-Location Sampling

We sought to find a method that improves HIV estimates obtained through time-location sampling (TLS) used to recruit most-at-risk populations (MARPs). The calibration on residuals (CARES) method attributes weights to TLS sampled individuals depending on the percentile to which their logistic regression residues belong. Using a real country database, provided by EMIS-2010, with 9591 men who have sex with men (MSM) and an HIV prevalence of 12.1%, we simulated three populations (termed "pseudo-populations") with different levels of HIV. From each pseudo-population, 1000 TLS samples were drawn, and the HIV prevalence estimated by the TLS method and by the CARES method were recorded and compared with the HIV prevalence of the 9591 men. Results showed that the CARES method improves estimates given by the TLS method by getting closer to the real HIV prevalence.

Injecting drug use during sex (known as "slamming") among men who have sex with men: Results from a time-location sampling survey conducted in five cities, France

BACKGROUND

In the last decade, European cities saw the development of "slamming," a practice related to chemsex that combines three elements: a sexual context, psychostimulant drug use, and injection practices. Epidemiological data on this practice is still sparse and media attention might have unintentionally distorted the size of this phenomenon. Therefore, we aimed to estimate the prevalence of men practicing slam and to identify factors associated with this practice.

METHODS

We used data from the Prevagay 2015 bio-behavioral survey to estimate the prevalence of slamming practices. A time-location sampling was performed among gay-labeled venues in five French cites. Behavioral information was recorded using a self-administered questionnaire. The HIV and HCV serostatus were investigated using ELISA tests on dried blood spots. The factors associated with slamming were assessed using a multiple logistic regression. We applied a weighting mechanism to enhance the generalizability of the estimates.

RESULTS

Among the 2646 men who have sex with men (MSM) included in our study, 3.1% reported slamming at least once during their lifetime (95% confidence interval (CI) = 2.2-4.3) and 1.6% (95% CI = 1-2.3) said they participated in a slamming session in the last 12 months. In the multivariate analysis, both HCV and HIV biological status were strongly associated with practicing "slam" in the last 12 months (OR = 13.37 (95% CI = 3.26-54.81) and 4.73 (95% CI = 1.58-14.44), respectively). Furthermore, a ten-point decrease in mental health scores was linked with the practice with an OR of 1.37 (95% CI = 1.08-1.73), indicating poorer mental health.

CONCLUSION

Even though slamming seems to involve a relatively small proportion of MSM, the vulnerability of this sub-group is high enough to justify setting up harm reduction measures and specific care. Training health professionals and creating services combining sexual health and drug dependence could be an effective response.

The evolving blood donor deferral policy for men who have sex with men: impact on the risk of HIV transmission by transfusion in France

BACKGROUND

Blood donation deferral for men who have sex with men (MSM) in France was reduced from permanent to 12 months in July 2016. To inform a further reduction of the deferral period, an HIV risk assessment was conducted with two scenarios: S1, 4-month deferral; S2, 4-month deferral only in the case of more than one sexual partner (i.e., similar to other blood donors).

METHODS

Baseline HIV residual risk (RR) was calculated from July 2016 to December 2017, using the Incidence Rate-Window Period method. The impact of both scenarios on RR was assessed using data from surveys on MSM and blood donors, to estimate 1) the number of additional MSM expected to donate in each scenario and 2) HIV incidence among these donors.

RESULTS

Baseline HIV RR was estimated at 1 in 6,380,000 donations. For S1, an additional 733 MSM donors, and an additional 0.09 HIV-positive donations were estimated, yielding an unchanged RR of 1 in 6,300,000. For S2, these numbers were estimated at 3102 and 3.92, respectively, yielding an RR of 1 in 4,300,000. Sensitivity analyses showed that, under worst-case assumptions, the RR would equal 1 in 6,225,000 donations for S1 and 1 in 3,000,000 for S2.

CONCLUSION

For both scenarios, the HIV RR remains very low. For S1, the risk is identical to the baseline RR. For S2, it is 1.5 times higher, and sensitivity analysis shows that this estimate is less robust than for S1. The French Minister of Health announced that S1 will be implemented in April 2020.

Screening for Human Immunodeficiency Virus Infection by Use of a Fourth-Generation Antigen/Antibody Assay and Dried Blood Spots: In-Depth Analysis of Sensitivity and Performance Assessment in a Cross-Sectional Study

We evaluated the performance of a fourth-generation antigen/antibody (Ag/Ab) assay for detecting HIV-1 infection on dried blood spots (DBS) both in a conventional laboratory environment and in an epidemiological survey corresponding to a real-life situation. Although a 2-log loss of sensitivity compared to that with plasma was observed when using DBS in an analytical analysis, the median delay of positivity between DBS and crude serum during the early phase postacute infection was 7 days. The performance of the fourth-generation assay on DBS was approximately similar to that of a third-generation (antibody only) assay using crude serum samples. Among 2,646 participants of a cross-sectional study in a population of men having sex with men, 428 DBS were found reactive, but negative results were obtained from 5 DBS collected from individuals who self-reported a positive HIV status, confirmed by detection of antiretroviral (ARV) drugs in their DBS. The data generated allowed us to estimate a sensitivity of 98.8% of the fourth-generation assay/DBS strategy in a high-risk population, even including a broad majority of individuals on ARV treatment among those HIV positive. Our study brings additional proofs that DBS testing using a fourth-generation immunoassay is a reliable strategy able to provide alternative approaches for both individual HIV testing and surveillance of various populations.

Prevalence of hepatitis C infection, screening and associated factors among men who have sex with men attending gay venues: a cross-sectional survey (PREVAGAY), France, 2015

Background

Over the last 20 years, Hepatitis C virus (HCV) infection prevalence has dramatically increased among HIV-infected men who have sex with men (MSM) in many countries worldwide. It is suspected that this increase is primarily driven by sexual behaviours linked to blood exposure. Monitoring these behaviours is crucial to understand the drivers of the epidemic. This study assessed the prevalence of chronic HCV infection among MSM attending gay venues and associated chronic HCV risk factors. HCV screening and associated factors were described.

Methods

The cross-sectional survey PREVAGAY, based on time-location sampling, was conducted in 2015 among MSM attending gay venues in 5 French metropolitan cities. A self-administered questionnaire was completed and capillary whole blood on dried blood spots (DBS) collected. Possible factors associated with chronic HCV prevalence and with HCV screening in the previous year were investigated using Poisson regression.

Results

Chronic HCV infection prevalence from DBS analysis was 0.7% [IC95%: 0.3–1.5] in the study’s 2645 participants and was 3.0% [1.5–5.8] in HIV-positive MSM. It was significantly higher in those who reported the following: (lifetime) slamming (with or without the sharing of injection equipment); (during the previous year) fisting and chemsex, unprotected anal intercourse with casual partners, using gay websites and/or of mobile-based GPS applications, and having more than 10 sexual partners.

Only 41.3% [38.2–44.5] of the participants reported HCV screening during the previous year. Screening was significantly more frequent in MSM under 30 years of age, those who were HIV-positive, those vaccinated against hepatitis B and meningococcus C, and those who reported the following (during the previous year): more than 10 sexual partners, at least one sexually transmitted infection and fisting.

Conclusion

Chronic HCV infection prevalence in MSM attending gay venues was significantly higher in HIV-positive MSM and in those with risky sexual behaviours. Reflecting current screening recommendations for specific populations, previous HCV screening was more frequent in HIV-positive individuals and those with risky sexual behaviours. Nevertheless, HCV screening coverage needs to be improved in these populations. Comprehensive medical management, which combines screening and linkage to care with prevention strategies, is essential to control HCV among MSM.

"Starfish Sampling": a Novel, Hybrid Approach to Recruiting Hidden Populations

We sought to leverage the strengths of time location sampling (TLS) and respondent-driven sampling (RDS) for surveys of hidden populations by combing elements of both methods in a new approach we call "starfish sampling." Starfish sampling entails random selection of venue-day-time units from a mapping of the locations where the population can be found, combined with short chains of peer referrals from their social networks at the venue or presenting to the study site later. Using the population of transmen in San Francisco as a case example, we recruited 122 eligible participants using starfish sampling: 79 at randomly selected venues, 11 on dating applications, and 32 by referral. Starfish sampling produced one of the largest community-recruited samples specifically for transmen to date. Starfish sampling is a flexibility method to recruit and sample hidden populations for whom conventional TLS and RDS may not work in theory or practice.