scholarly journals Influence of serosorting and intervention-mediated changes in serosorting on the population-level HIV transmission impact of pre-exposure prophylaxis among men who have sex with men: a mathematical modelling study

2020 ◽  
Author(s):  
Linwei Wang ◽  
Nasheed Moqueet ◽  
Anna Simkin ◽  
Jesse Knight ◽  
Huiting Ma ◽  
...  
Keyword(s):  
Condom Use ◽  
Hiv Transmission ◽  
Population Level ◽  
Poor Adherence ◽  
Hiv Incidence ◽  
Individual Level ◽  
Prep Implementation ◽  
Mixing Patterns ◽  
Sex With Men ◽  
Exposure Prophylaxis

ABSTRACTBackgroundHIV pre-exposure prophylaxis (PrEP) may change serosorting patterns. We examined the influence of serosorting on the population-level HIV transmission impact of PrEP, and how impact could change if PrEP users stopped serosorting.MethodsWe developed a compartmental HIV transmission model parameterized with bio-behavioural and HIV surveillance data among men who have sex with men in Canada. We separately fit the model with serosorting and without serosorting (random partner-selection proportional to availability by HIV-status (sero-proportionate)), and reproduced stable HIV epidemics (2013-2018) with HIV-prevalence 10.3%-24.8%, undiagnosed fraction 4.9%-15.8%, and treatment coverage 82.5%-88.4%. We simulated PrEP-intervention reaching stable coverage by year-1 and compared absolute difference in relative HIV-incidence reduction 10-year post-intervention (PrEP-impact) between: models with serosorting vs. sero-proportionate mixing; and scenarios in which PrEP users stopped vs. continued serosorting. We examined sensitivity of results to PrEP-effectiveness (44%-99%) and coverage (10%-50%).FindingsModels with serosorting predicted a larger PrEP-impact compared with models with sero-proportionate mixing under all PrEP-effectiveness and coverage assumptions (median (inter-quartile-range): 8.1%(5.5%-11.6%)). PrEP users” stopping serosorting reduced PrEP-impact compared with when PrEP users continued serosorting: reductions in PrEP-impact were minimal (2.1%(1.4%-3.4%)) under high PrEP-effectiveness (86%-99%); however, could be considerable (10.9%(8.2%-14.1%)) under low PrEP effectiveness (44%) and high coverage (30%-50%).InterpretationModels assuming sero-proportionate mixing may underestimate population-level HIV-incidence reductions due to PrEP. PrEP-mediated changes in serosorting could lead to programmatically-important reductions in PrEP-impact under low PrEP-effectiveness (e.g. poor adherence/retention). Our findings suggest the need to monitor sexual mixing patterns to inform PrEP implementation and evaluation.FundingCanadian Institutes of Health ResearchRESEARCH IN CONTEXTEvidence before this studyWe searched PubMed for full-text journal articles published between Jan 1, 2010, and Dec 31, 2017, using the MeSH terms “pre-exposure prophylaxis (PrEP)” and “homosexuality, male” and using key words (“pre-exposure prophylaxis” or “preexposure prophylaxis” or “PrEP”) and (“men who have sex with men” or “MSM”) in titles and abstracts. Search results (520 records) were reviewed to identify publications which examined the population-level HIV transmission impact or population-level cost-effectiveness of PrEP in high-income settings. We identified a total of 18 modelling studies of PrEP impact among men who have sex with men (MSM) and four studies were based on the same model with minor variations (thus only the most recent one was included). Among the 15 unique models of PrEP impact, three included serosorting. A total of nine models have assessed the individual-level behaviour change among those on PrEP and its influence on the transmission impact of PrEP. Specifically, the models examined increases in number of partners and reductions in condom use. Most models predicted that realistic increases in partner number or decreases in condom use would not fully offset, but could weaken, PrEP”s impact on reducing HIV transmission. We did not identify any study that examined the influence of serosorting patterns on the estimated transmission impact of PrEP at the population-level, or what could happen to HIV incidence if the use of PrEP changes serosorting patterns.Added value of this studyWe used a mathematical model of HIV transmission to estimate the influence of serosorting and PrEP-mediated changes in serosorting on the transmission impact of PrEP at the population-level among MSM. We found the impact of PrEP was higher under epidemics with serosorting, compared with comparable epidemics simulated assuming sero-proportionate mixing. Under epidemics with serosorting, when PrEP users stopped serosorting (while other men continue to serosort among themselves) we found a reduced PrEP impact compared with scenarios when PrEP users continued to serosort. The magnitude of reduction in PrEP impact was minimal if PrEP-effectiveness was high; however, could be programmatically-meaningful in the context of low PrEP-effectiveness (e.g., poor adherence or retention) and high PrEP coverage. To our knowledge, our study is the first to directly examine the influence of serosorting and PrEP-mediated changes in serosorting on the transmission impact of PrEP and its underlying mechanism.Implications of all the available evidenceOur findings suggest that models which do not consider baseline patterns of serosorting among MSM could potentially underestimate PrEP impact. In addition to monitoring individual-level behavioural change such as condom use, our findings highlight the need to monitor population-level sexual mixing patterns and their changes over time among MSM in the design and evaluation of PrEP implementation.

scholarly journals Likely impact of pre-exposure prophylaxis on HIV epidemics among men who have sex with men

Sexual Health ◽  
2017 ◽  
Vol 14 (1) ◽  
pp. 97 ◽  
Author(s):  
Iryna B. Zablotska
Keyword(s):  
Hiv Transmission ◽  
Population Level ◽  
Combination Prevention ◽  
The Us ◽  
Implementation Studies ◽  
Prep Implementation ◽  
Modelling Studies ◽  
Sex With Men ◽  
Exposure Prophylaxis ◽  
The Impact

Rapid developments in the field of HIV pre-exposure prophylaxis (PrEP) with antiretrovirals offer a promise to bring HIV transmission among gay and other men who have sex with men (MSM) to zero by 2030. This review evaluates studies, which modelled the impact of PrEP on HIV diagnoses, and discusses the progress towards PrEP implementation. Studies in English, conducted after 2010 among MSM in countries of the Organization for Economic Cooperation and Development (OECD) were reviewed. Six modelling studies were included, three of which had been conducted outside the US. None of the published models showed that PrEP alone can reduce HIV diagnoses to zero and eliminate HIV transmission by 2030. However, PrEP in combination with other biomedical interventions can reduce HIV diagnoses on the population level by ~95%. Other upcoming biomedical prevention strategies may strengthen combination prevention. Access to PrEP remains limited, even in the OECD countries. Modelling studies can assist governments with decision-making about PrEP implementation and add urgency to the implementation of PrEP. More work is needed on modelling of the impact of PrEP on HIV diagnoses trends outside the US where PrEP implementation is in its early stages.

scholarly journals 1701. Added Benefits of Pre-exposure Prophylaxis Use on HIV Incidence with Minimal Changes in Efficiency in the Context of High Treatment Engagement among Men Who Have Sex with Men

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S833-S833
Author(s):  
Alyson L Singleton ◽  
Brandon D Marshall ◽  
Xiao Zang ◽  
Amy S Nunn ◽  
William C Goedel
Keyword(s):  
African American ◽  
Hiv Infection ◽  
Hiv Transmission ◽  
Treatment Engagement ◽  
Hiv Incidence ◽  
Black African ◽  
African American Msm ◽  
Sex With Men ◽  
Exposure Prophylaxis ◽  
High Treatment

Abstract Background Although there is ongoing debate over the need for substantial increases in PrEP use when antiretroviral treatment confers the dual benefits of reducing HIV-related morbidity and mortality and the risk of HIV transmission, no studies to date have quantified the potential added benefits of PrEP use in settings with high treatment engagement across variable sub-epidemics in the United States. Methods We used a previously published agent-based network model to simulate HIV transmission in a dynamic network of 17,440 Black/African American and White MSM in Atlanta, Georgia from 2015 to 2024 to understand how the magnitude of reductions in HIV incidence attributable to varying levels of PrEP use (0–90%) changes in potential futures where high levels of treatment engagement (i.e. the UNAIDS ‘90-90-90’ goals and eventual ‘95-95-95’ goals) are achieved and maintained, as compared to current levels of treatment engagement in Atlanta (Figure 1). Model inputs related to HIV treatment engagement among Black/African American and White men who have sex with men in Atlanta. A comparison of current levels of treatment engagement (Panel A) to treatment engagement at ‘90-90-90’ (Panel B) and ‘95-95-95’ goals (Panel C). Results Even at achievement and maintenance of ‘90-90-90’ goals, 75% PrEP coverage reduced incidence rates by an additional 67.9% and 74.2% to 1.53 (SI: 1.39, 1.70) and 0.355 (SI: 0.316, 0.391) per 100 person-years for Black/African American and White MSM, respectively (Figure 2), compared to the same scenario with no PrEP use. Additionally, an increase from 15% PrEP coverage to 75% under ‘90-90-90’ goals only increased person-years of PrEP use per HIV infection averted, a measure of efficiency of PrEP, by 8.1% and 10.5% to 26.7 (SI: 25.6, 28.0) and 73.3 (SI: 70.6, 75.7) among Black/African American MSM and White MSM, respectively (Figure 3). Overall (Panel A) and race-stratified (Panel B and Panel C) marginal changes in HIV incidence over ten years among Black/African American and White men who have sex with men in Atlanta across scenarios of varied levels of treatment engagement among agents living with HIV infection and levels of pre-exposure prophylaxis use among HIV-uninfected agents. Note: All changes are calculated within each set of treatment scenarios relative to a scenario where no agents use pre-exposure prophylaxis. Person-years of pre-exposure prophylaxis use per HIV infection averted among Black/African American (Panel A) and White (Panel B) men who have sex with men in Atlanta across scenarios of varied levels of treatment engagement among agents living with HIV infection and levels of pre-exposure prophylaxis use among HIV-uninfected agents. Note: The number of HIV infections averted is calculated within each set of treatment scenarios relative to a scenario where no agents use pre-exposure prophylaxis. Conclusion Even in the context of high treatment engagement, substantial expansion of PrEP use still contributes to meaningful decreases in HIV incidence among MSM with minimal changes in person-years of PrEP use per HIV infection averted, particularly for Black/African American MSM. Disclosures All Authors: No reported disclosures

scholarly journals Preparing for PrEP: estimating the size of the population eligible for HIV pre-exposure prophylaxis among men who have sex with men in England

2019 ◽  
Vol 95 (7) ◽  
pp. 484-487 ◽  
Author(s):  
Holly D Mitchell ◽  
Sarika Desai ◽  
Hamish Mohammed ◽  
Koh Jun Ong ◽  
Martina Furegato ◽  
...  
Keyword(s):  
Population Level ◽  
Annual Number ◽  
Hiv Incidence ◽  
Eligibility Criteria ◽  
Transmitted Infection ◽  
Negative Test ◽  
The Past ◽  
Sex With Men ◽  
Exposure Prophylaxis ◽  
Hiv Negative

ObjectivesThe size of the population of men who have sex with men (MSM) who may be eligible for HIV pre-exposure prophylaxis (HIV-PrEP) in England remains unknown. To plan for a national PrEP implementation trial, we estimated the number of MSM attending sexual health clinics (SHCs) that may be eligible for HIV-PrEP in England.MethodsSexually transmitted infection (STI) surveillance data from 2010 to 2015 from the GUMCAD surveillance system were used to estimate the annual number of HIV-negative MSM who may be eligible for HIV-PrEP in England. Based on national eligibility criteria, we identified HIV-negative MSM attending SHCs with a HIV-negative test in the past year and used diagnosed bacterial STI (past year) in this group as a proxy for condomless sex and eligibility for HIV-PrEP. We estimated HIV incidence per 100 person-years (py) in these groups in 2014.ResultsDuring 2010–2015, the number of HIV-negative MSM attending SHCs with a HIV-negative test in the past year doubled from 14 643 to 29 023, and HIV incidence in this group was 1.9 (95% CI 1.6 to 2.2) per 100 py in 2014. In the same period, the subgroup with a bacterial STI diagnosis (past year), and therefore considered potentially eligible for HIV-PrEP in this analysis, increased from 4365 (30%) to 10 276 (35%). HIV incidence in this subgroup was 3.3 (95% CI 2.7 to 4.0) per 100 py in 2014.ConclusionsIn 2015, approximately 10 000 HIV-negative MSM were considered potentially eligible for HIV-PrEP based on clinic history in GUMCAD. These data were used to inform the initial recruitment target for the PrEP Impact Trial and will inform future evaluations at a population level.

scholarly journals Past dynamics of HIV transmission among men who have sex with men in Montreal, Canada: a mathematical modelling study

2021 ◽  
Author(s):  
Rachael M Milwid ◽  
Yiqing Xia ◽  
Carla Doyle ◽  
Joseph Cox ◽  
Gilles Lambert ◽  
...  
Keyword(s):  
Hiv Transmission ◽  
Age Groups ◽  
Population Level ◽  
Hiv Infections ◽  
Hiv Incidence ◽  
Agent Based ◽  
Treatment And Prevention ◽  
Sex With Men ◽  
Hiv Acquisition

Background: Gay, bisexual, and other men who have sex with men (gbMSM) experience disproportionate risks of HIV acquisition/transmission. In 2017, Montréal became the first Canadian Fast-Track city, setting the 2030 goal of zero new HIV infections. To inform local elimination efforts, we estimate the evolving role of prevention/risk behaviours and HIV transmission dynamics among gbMSM in Montréal between 1975-2019. Methods: Data from local bio-behavioural surveys were analyzed to develop, parameterize, and calibrate an agent-based model of sexual HIV transmission. Partnership dynamics, the HIV natural history, and treatment and prevention strategies were considered. The model simulations were analyzed to estimate the fraction of HIV acquisitions/transmissions attributable to specific age-groups and unmet prevention needs. Results: The model-estimated HIV incidence peaked in 1985 (2.2%; 90%CrI: 1.3-2.8%) and decreased to 0.1% (90%CrI: 0.04-0.3%) in 2019. Between 1990-2017, the majority of HIV acquisitions/transmissions occurred among men aged 25-44 years, and men aged 35-44 thereafter. The unmet prevention needs of men with >10 annual anal sex partners contributed 92-94% of transmissions and 63-73% of acquisitions annually. The primary stage of HIV played an increasing role over time, contributing to 12%-27% of annual transmissions over 1990-2019. In 2019, approximately 75% of transmission events occurred from men who had discontinued, or never initiated ART. Conclusions: The evolving HIV landscape has contributed to the recent low HIV incidence among MSM in Montréal. The shifting dynamics identified in this study highlight the need for continued population-level surveillance to identify unmet prevention needs and core groups on which to prioritize elimination efforts.

scholarly journals Implementation of a Rapid Entry Program Decreases Time to Viral Suppression Among Vulnerable Persons Living With HIV in the Southern United States

2018 ◽  
Vol 5 (6) ◽  
Author(s):  
Jonathan Colasanti ◽  
Jeri Sumitani ◽  
C Christina Mehta ◽  
Yiran Zhang ◽  
Minh Ly Nguyen ◽  
...  
Keyword(s):  
United States ◽  
Viral Suppression ◽  
Hiv Transmission ◽  
Positive Impact ◽  
Population Level ◽  
The United States ◽  
Clinic Visit ◽  
Art Initiation ◽  
Persons Living With Hiv ◽  
Sex With Men

Abstract Background Rapid entry programs (REPs) improve time to antiretroviral therapy (ART) initiation (TAI) and time to viral suppression (TVS). We assessed the feasibility and effectiveness of a REP in a large HIV clinic in Atlanta, Georgia, serving a predominately un- or underinsured population. Methods The Rapid Entry and ART in Clinic for HIV (REACH) program was implemented on May 16, 2016. We performed a retrospective cohort study with the main independent variable being period of enrollment: January 1, 2016, through May 15, 2016 (pre-REACH); May 16, 2016, through July 31, 2016 (post-REACH). Included individuals were HIV-infected and new to the clinic with detectable HIV-1 RNA. Six-month follow-up data were collected for each participant. Survival analyses were conducted for TVS. Logistic and linear regression analyses were used to evaluate secondary outcomes: attendance at first clinic visit, viral suppression, TAI, and time to first attended provider visit. Results There were 117 pre-REACH and 90 post-REACH individuals. Median age (interquartile range [IQR]) was 35 (25–45) years, 80% were male, 91% black, 60% men who have sex with men, 57% uninsured, and 44% active substance users. TVS decreased from 77 (62–96) to 57 (41–70) days (P < .0022). Time to first attended provider visit decreased from 17 to 5 days, and TAI from 21 to 7 days (P < .0001), each remaining significant in adjusted models. Conclusions This is the largest rapid entry cohort described in the United States and suggests that rapid entry is feasible and could have a positive impact on HIV transmission at the population level.

Factors influencing uptake of pre-exposure prophylaxis: some qualitative insights from an intervention study of men who have sex with men in China

Sexual Health ◽  
2018 ◽  
Vol 15 (1) ◽  
pp. 39 ◽  
Author(s):  
Chunxing Liu ◽  
Yingying Ding ◽  
Zhen Ning ◽  
Meiyang Gao ◽  
Xing Liu ◽  
...  
Keyword(s):  
Hiv Risk ◽  
Intervention Study ◽  
Implementation Strategies ◽  
Self Assessment ◽  
Risk Beliefs ◽  
Group Data ◽  
Prep Implementation ◽  
Substantial Risk ◽  
Sex With Men ◽  
Exposure Prophylaxis

Background: Pre-exposure prophylaxis (PrEP) is a biomedical approach for preventing the acquisition of HIV in populations at substantial risk for HIV. However, its uptake among men who have sex with men (MSM) is low in China. The study aimed to identify factors that might influence MSM’s uptake and use of PrEP. Methods: In-depth interviews were conducted with 32 self-identified MSM from a PrEP intervention study evaluating daily oral tenofovir disoproxil fumarate (TDF) to prevent HIV infection. Of these men, 11 were presently using the ‘TDF’ group; 8 from the ‘change-over’ group (i.e. initially used PrEP but subsequently quitted); and 13 from the non-user group. Data were analysed using thematic approach. Results: Perception of low HIV risk, mistrust of the national PrEP program, and concerns of side effects were the main reasons for not wanting to use PrEP. Also, lack of main sexual partner’s support, difficulties in adhering to the daily TDF regimen, and the inconvenient schedules in securing the medicine were the major reasons for not wanting to use or quitting the use of PrEP. On the other hand, perceived high HIV risk, beliefs in efficacy of PrEP, and worries of transmitting HIV to families were the major motives for PrEP uptake. Conclusions: Findings suggest that PrEP implementation strategies should first address issues including but not limited to accurate self-assessment of HIV risk, mistrust and limited knowledge about medical trials and PrEP, and ease of accessing PrEP.

Impact of HIV risk perception on both pre-exposure prophylaxis and condom use

2019 ◽  
pp. 135910531988392
Author(s):  
Marion Di Ciaccio ◽  
Luis Sagaon-Teyssier ◽  
Christel Protière ◽  
Mohamed Mimi ◽  
Marie Suzan-Monti ◽  
...  
Keyword(s):  
Risk Perception ◽  
High Risk ◽  
Condom Use ◽  
Hiv Risk ◽  
Health Behaviours ◽  
Two Dimensions ◽  
Hiv Risk Perception ◽  
Sex With Men ◽  
Exposure Prophylaxis ◽  
Trajectory Modelling

Risk perception is one of the several important factors impacting sexual health behaviours. This study investigated the evolution of HIV risk perception on pre-exposure prophylaxis adherence and condom use in men who have sex with men at high risk of HIV and associated factors. Group-based trajectory modelling helped in identifying patterns of risk perception, pre-exposure prophylaxis adherence and condom use over time. The association between the former and the latter two dimensions was then investigated. An estimated 61 per cent ( p < 0.001) of participants perceiving low risk and 100 per cent ( p < 0.001) of those perceiving high risk had systematic pre-exposure prophylaxis adherence, while an estimated 49 per cent ( p < 0.001) and 99.8 per cent ( p < 0.001), respectively, reported low-level condom use.

scholarly journals Impact of sexual trajectories of men who have sex with men on the reduction in HIV transmission by pre-exposure prophylaxis

Epidemics ◽  
2019 ◽  
Vol 28 ◽  
pp. 100337 ◽  
Author(s):  
Ganna Rozhnova ◽  
Janneke C.M. Heijne ◽  
Maartje Basten ◽  
Chantal den Daas ◽  
Amy Matser ◽  
...  
Keyword(s):  
Hiv Transmission ◽  
Sex With Men ◽  
Exposure Prophylaxis
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