Behavioural, not biological, factors drive the HCV epidemic among HIV-positive MSM: HCV and HIV modelling analysis including HCV treatment-as-prevention impact

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Abstract

<div class="section"> <a class="named-anchor" id="d4506966e185">  </a> <h5 class="section-title" id="d4506966e186">Background</h5> <p id="d4506966e188">Uncertainty surrounds why hepatitis C virus (HCV) is concentrated among HIV-positive men who have sex with men (MSM). We used mathematical modelling to explore reasons for these infection patterns, and implications for HCV treatment-as-prevention. </p> </div><div class="section"> <a class="named-anchor" id="d4506966e190">  </a> <h5 class="section-title" id="d4506966e191">Methods</h5> <p id="d4506966e193">Using a joint MSM HIV/HCV transmission model parameterized with UK behavioural data, we considered how biological (heightened HCV infectivity and reduced spontaneous clearance among HIV-positive MSM) and/or behavioural factors (preferential sexual mixing by HIV status and risk heterogeneity) could concentrate HCV infection in HIV-positive MSM as commonly observed (5-20 times the HCV prevalence in HIV-negative MSM; defined as the HCV ratio). We explored how HCV treatment-as-prevention impact varies under differing HCV ratios. </p> </div><div class="section"> <a class="named-anchor" id="d4506966e195">  </a> <h5 class="section-title" id="d4506966e196">Results</h5> <p id="d4506966e198">Biological factors produced low HCV ratios (< 3), not explaining the skewed epidemic. However, combining preferential mixing by HIV status with sexual risk behaviour heterogeneity produced high HCV ratios (> 10) that were highly sensitive to both factors. Irrespective of the HCV ratio or behavioural/biological factors, HCV treatment of HIV-diagnosed MSM markedly reduced the HCV prevalence among HIV-positive MSM, but less impact was achieved among all MSM for lower HCV ratios. </p> </div><div class="section"> <a class="named-anchor" id="d4506966e200">  </a> <h5 class="section-title" id="d4506966e201">Conclusions</h5> <p id="d4506966e203">Sexual behaviour patterns likely drive observed HCV infection patterns among HIV-positive MSM. Changes in these patterns could disseminate HCV amongst HIV-negative MSM, limiting the impact of targeting HCV treatment to HIV-diagnosed MSM. </p> </div>

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Most cited references 26

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Antiretroviral Therapy for the Prevention of HIV-1 Transmission.

Myron S Cohen, Ying Q Chen, Marybeth McCauley … (2016)

An interim analysis of data from the HIV Prevention Trials Network (HPTN) 052 trial showed that antiretroviral therapy (ART) prevented more than 96% of genetically linked infections caused by human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. ART was then offered to all patients with HIV-1 infection (index participants). The study included more than 5 years of follow-up to assess the durability of such therapy for the prevention of HIV-1 transmission.

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Record: found
Abstract: found
Article: not found

Recent epidemic of acute hepatitis C virus in HIV-positive men who have sex with men linked to high-risk sexual behaviours.

Sanjay Bhagani, G. Dusheiko, Martin Fisher … (2007)

To characterize the mode of hepatitis C virus (HCV) transmission in a recent epidemic of acute HCV in HIV-infected individuals using linked molecular and clinical epidemiological studies. Individuals diagnosed with acute HCV between 1999 and 2005 at three urban HIV units in the UK were enrolled into a phylogenetic and case-control study. Phylogenetic trees were constructed from the amplified sequences of the E1/E2 region of the HCV genome and were used to compare cases with unrelated sequences. A questionnaire-based, case-control study using matched controls recruited from each HIV unit identified putative transmission factors. One hundred and eleven HIV-positive men who have sex with men with acute HCV (genotype 1: 84%) were enrolled. Phylogenetic analysis of 93 E1/E2 sequences revealed seven monophyletic clusters signifying multiple independent HCV lineages co-circulating in the HIV-positive population. Permucosal rather than percutaneous transmission factors were associated with case/control status. Cases (n = 60) had more sexual partners, increased levels of high-risk sexual behaviour and were more likely to have shared drugs via a nasal or anal route in the preceding year in comparison with controls (n = 130). Sex in a group of more than two people was the strongest predictor of case/control status; odds ratios associated with participation in two or at least three types of high-risk sexual behaviour in a group were 9.16 (95% confidence interval, 3.51-23.90) and 23.50 (95% confidence interval, 9.47-58.33), respectively. The identified co-circulating HCV lineages belong to different subtypes and genotypes, implying that rather than viral change, the epidemic is due to permucosal transmission factors that should be the focus of public health interventions.

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Condom effectiveness for HIV prevention by consistency of use among men who have sex with men in the United States.

Dawn K. Smith, Jeffrey H Herbst, Xinjiang Zhang … (2015)

We derived an estimate of male condom effectiveness during anal sex among men who have sex with men (MSM) because the most widely used estimate of condom effectiveness (80%) was based on studies of persons during heterosexual sex with an HIV-positive partner. Assessed male condom effectiveness during anal sex between MSM in 2 prospective cohort studies of HIV incidence by self-reported consistency of use. Analyzed data combined from US participants in the EXPLORE trial (1999-2001) public use data set and in the VAX 004 trial (1998-1999) data set. Initially, HIV-uninfected MSM enrolled in these trials completed baseline and semiannual interviews about their sexual behaviors with male partners and underwent HIV testing. Using a time-to-event model, effectiveness of consistent condom use in preventing HIV infection was estimated among men reporting receptive and/or insertive anal sex with an HIV-positive partner and consistency of condom use. Among MSM reporting any anal sex with an HIV-positive male partner, we found 70% effectiveness with reported consistent condom use (compared with never use) and no significant protection when comparing sometimes use to never use. This point estimate for MSM was less than the 80% effectiveness estimate reported for heterosexuals in HIV-discordant couples reporting consistent condom use. However, the point estimates in the 2 populations are not statistically different. Only 16% of MSM reported consistent condom use during anal sex with male partners of any HIV status over the entire observation period. These estimates are useful for counseling efforts and for modeling the impact and comparative effectiveness of condoms and other prevention methods used by MSM.