Is the HCV-HIV co-infection prevalence amongst injecting drug users a marker for the level of sexual and injection related HIV transmission?

Modeling the impact of a supervised consumption site on HIV and HCV transmission among people who inject drugs in three counties in California, USA

BACKGROUND

Supervised consumption sites (SCS) have been shown to reduce receptive syringe sharing among people who inject drugs (PWID) in the United States and elsewhere, which can prevent HIV and hepatitis C virus (HCV) transmission. PWID are at risk of disease transmission and may benefit from SCS, however legislation has yet to support their implementation. This study aims to determine the potential impact of SCS implementation on HIV and HCV incidence among PWID in three California counties.

METHODS

A dynamic HIV and HCV joint transmission model among PWID (sexual and injecting transmission of HIV, injecting transmission of HCV) was calibrated to epidemiological data for three counties: San Francisco, Los Angeles, and San Diego. The model incorporated HIV and HCV disease stages and HIV and HCV treatment. Based on United States data, we assumed access to SCS reduced receptive syringe sharing by a relative risk of 0.17 (95 % CI: 0.04-1.03). This model examined scaling-up SCS coverage from 0 % to 20 % of the PWID population within the respective counties and assessed its impact on HIV and HCV incidence rates after 10 years.

RESULTS

By increasing SCS from 0 % to 20 % coverage among PWID, 21.8 % (95 % CI: -1.2-32.9 %) of new HIV infections and 28.3 % (95 % CI: -2.0-34.5 %) of new HCV infections among PWID in San Francisco County, 17.7 % (95 % CI: -1.0-30.8 %) of new HIV infections and 29.8 % (95 % CI: -2.1-36.1 %) of new HCV infections in Los Angeles County, and 32.1 % (95 % CI: -2.8-41.5 %) of new HIV infections and 24.3 % (95 % CI: -1.6-29.0 %) of new HCV infections in San Diego County could be prevented over ten years.

CONCLUSION

Our models suggest that SCS is an important intervention to enable HCV elimination and could help end the HIV epidemic among PWID in California. It could also have additional benefits such facilitating pathways into drug treatment programs and preventing fatal overdose.

Modelling the impact of HIV and HCV prevention and treatment interventions for people who inject drugs in Dar es Salaam, Tanzania

Introduction

People who inject drugs (PWID) in Dar es Salaam, Tanzania, have a high prevalence of HIV and hepatitis C virus (HCV). While needle and syringe programmes (NSP), opioid agonist therapy (OAT) and anti‐retroviral therapy (ART) are available in Tanzania, their coverage is sub‐optimal. We assess the impact of existing and scaled up harm reduction (HR) interventions on HIV and HCV transmission among PWID in Dar es Salaam.

Methods

An HIV and HCV transmission model among PWID in Tanzania was calibrated to data over 2006–2018 on HIV (∼30% and ∼67% prevalence in males and females in 2011) and HCV prevalence (∼16% in 2017), numbers on HR interventions (5254 ever on OAT in 2018, 766–1479 accessing NSP in 2017) and ART coverage (63.1% in 2015). We evaluated the impact of existing interventions in 2019 and impact by 2030 of scaling‐up the coverage of OAT (to 50% of PWID), NSP (75%, both combined termed “full HR”) and ART (81% with 90% virally suppressed) from 2019, reducing sexual HIV transmission by 50%, and/or HCV‐treating 10% of PWID infected with HCV annually.

Results

The model projects HIV and HCV prevalence of 19.0% (95% credibility interval: 16.4–21.2%) and 41.0% (24.4–49.0%) in 2019, respectively. For HIV, 24.6% (13.6–32.6%) and 70.3% (59.3–77.1%) of incident infections among male and female PWID are sexually transmitted, respectively. Due to their low coverage (22.8% for OAT, 16.3% for NSP in 2019), OAT and NSP averted 20.4% (12.9–24.7%) of HIV infections and 21.7% (17.0–25.2%) of HCV infections in 2019. Existing ART (68.5% coverage by 2019) averted 48.1% (29.7–64.3%) of HIV infections in 2019. Scaling up to full HR will reduce HIV and HCV incidence by 62.6% (52.5–74.0%) and 81.4% (56.7–81.4%), respectively, over 2019–2030; scaled up ART alongside full HR will decrease HIV incidence by 66.8% (55.6–77.5%), increasing to 81.5% (73.7–87.5%) when sexual risk is also reduced. HCV‐treatment alongside full HR will decrease HCV incidence by 92.4% (80.7–95.8%) by 2030.

Conclusions

Combination interventions, including sexual risk reduction and HCV treatment, are needed to eliminate HCV and HIV among PWID in Tanzania.

What is needed to achieve HCV microelimination among HIV-infected populations in Andalusia, Spain: a modeling analysis

BACKGROUND

Scale-up of hepatitis C virus (HCV) treatment for HIV/HCV coinfected individuals is occurring in Spain, the vast majority (> 85%) with a reported history of injecting drug use and a smaller population of co-infected men who have sex with men (MSM). We assess impact of recent treatment scale-up to people living with HIV (PLWH) and implications for achieving the WHO HCV incidence elimination target (80% reduction 2015-2030) among PLWH and overall in Andalusia, Spain, using dynamic modeling.

METHODS

A dynamic transmission model of HCV/HIV coinfection was developed. The model was stratified by people who inject drugs (PWID) and MSM. The PWID component included dynamic HCV transmission from the HCV-monoinfected population. The model was calibrated to Andalusia based on published data and the HERACLES cohort (prospective cohort of HIV/HCV coinfected individuals representing > 99% coinfected individuals in care in Andalusia). From HERACLES, we incorporated HCV treatment among diagnosed PLWH of 10.5%/year from 2004 to 2014, and DAAs at 33%/year from 2015 with 94.8% SVR. We project the impact of current and scaled-up HCV treatment for PLWH on HCV prevalence and incidence among PLWH and overall.

RESULTS

Current treatment rates among PLWH (scaled-up since 2015) could substantially reduce the number of diagnosed coinfected individuals (mean 76% relative reduction from 2015 to 2030), but have little impact on new diagnosed coinfections (12% relative reduction). However, DAA scale-up to PWLH in 2015 would have minimal future impact on new diagnosed coinfections (mean 9% relative decrease from 2015 to 2030). Similarly, new cases of HCV would only reduce by a mean relative 29% among all PWID and MSM due to ongoing infection/reinfection. Diagnosing/treating all PLWH annually from 2020 would increase the number of new HCV infections among PWLH by 28% and reduce the number of new HCV infections by 39% among the broader population by 2030.

CONCLUSION

Targeted scale-up of HCV treatment to PLWH can dramatically reduce prevalence among this group but will likely have little impact on the annual number of newly diagnosed HIV/HCV coinfections. HCV microelimination efforts among PWLH in Andalusia and settings where a large proportion of PLWH have a history of injecting drug use will require scaled-up HCV diagnosis and treatment among PLWH and the broader population at risk.

Estimating the contribution of stimulant injection to HIV and HCV epidemics among people who inject drugs and implications for harm reduction: A modeling analysis

BACKGROUND

Stimulants, such as amphetamines and cocaine, are widely injected among people who inject drugs (PWID). Systematic reviews indicate stimulant injection is associated with HIV and HCV among PWID. Using these associations, we estimated the contribution of stimulant injection to HIV and HCV transmission among PWID.

METHODS

We modeled HIV and HCV transmission among PWID, incorporating excess injecting and sexual risk among PWID who inject stimulants. We simulated three illustrative settings with different stimulants injected, prevalence of stimulant injecting, and HIV/HCV epidemiology. We estimated one-year population attributable fractions of stimulant injection on new HIV and HCV infections, and impact of scaling up needle-syringe programs (NSP).

RESULTS

In low prevalence settings of stimulant injection (St. Petersburg-like, where 13 % inject amphetamine), 9% (2.5-97.5 % interval [95 %I]: 6-15 %) and 7% (95 %I 4-11 %) of incident HIV and HCV cases, respectively, could be associated with stimulant injection in the next year. With moderate stimulant injection (Montreal-like, where 34 % inject cocaine), 29 % (95 %I: 19-37 %) and 19 % (95 %I: 16-21 %) of incident HIV and HCV cases, respectively, could be associated with stimulant injection. In high-burden settings like Bangkok where 65 % inject methamphetamine, 23 % (95%I:10-34%) and 20 % (95%I: 9-27%) of incident HIV and HCV cases could be due to stimulant injection. High-coverage NSP (60 %) among PWID who inject stimulants could reduce HIV (by 22-65 %) and HCV incidence (by 7-11 %) in a decade.

DISCUSSION

Stimulant injection contributes substantially to HIV and HCV among PWID. NSP scale-up and development of novel interventions among PWID who inject stimulants are warranted.

Prevalence of HIV/Hepatitis C Virus Co-Infection and Injection Risk Correlations in People Who Inject Drugs in Colombia: A Cross-Sectional Study Using Respondent Driven Sampling

Background: In Colombia, an exponential growth of people who inject drugs (PWID) has been reported over the past decades. The main burden of disease in PWID is attributed to human immunodeficiency virus (HIV) and hepatitis C virus (HCV) and their co-infection is associated with poor prognosis, high morbidity and treatment related implications. Nevertheless, the prevalence of HIV/HCV co-infection in Colombian PWIDs is unknown. Objective: To determine the prevalence, demographic characteristics, and injecting behaviors of HIV/HCV co-infected PWID in Colombia. Methods: This was a cross-sectional study of 1,123 PWID recruited by respondent driven sampling in five Colombian cities between January and June of 2014. Each participant completed a quantitative survey, and blood samples for HIV and HCV antibody testing were obtained. A multinomial logistic regression was used for statistical analysis. Results: Average participant age was 26.3 ± 6.5 years, and the majority was male (86%). HIV or HCV mono-infection prevalence was 27.6%, while co-infection was 3.3%. Compared with PWID with mono-infection, co-infected PWID exhibited higher odds of: injecting ≥4 times daily (OR: 3.5; CI: 1.7-7.2; p < .001), cleaning needles and syringes with water (OR 3.2; CI: 1.6-6.3; p < .001), passing drug mix between syringes (OR: 2.7; CI: 1.3-5.3; p = .04), injecting on illegal indoor shooting galleries (OR: 2.4; CI: 1.0-5.3, p = .02), and getting injected by someone who charges for injecting (OR 2.3; CI: 1.0-5.2; p = .04). Conclusion: Prevalence of HIV/HCV co-infection among PWID in Colombia is lower than that reported in other countries. However, addressing the identified demographic characteristics and injection risk behaviors of co-infected PWID is essential for the implementation of broadly available harm reduction interventions as well as routine HIV/HCV testing and treatment strategies aiming to control the spread of both viruses and their associated morbidity and mortality.

Mathematical modeling of hepatitis c virus (HCV) prevention among people who inject drugs: A review of the literature and insights for elimination strategies

In 2016, the World Health Organization issued global elimination targets for hepatitis C virus (HCV), including an 80% reduction in HCV incidence by 2030. The vast majority of new HCV infections occur among people who inject drugs (PWID), and as such elimination strategies require particular focus on this population. As governments urgently require guidance on how to achieve elimination among PWID, mathematical modeling can provide critical information on the level and targeting of intervention are required. In this paper we review the epidemic modeling literature on HCV transmission and prevention among PWID, highlight main differences in mathematical formulation, and discuss key insights provided by these models in terms of achieving WHO elimination targets among PWID. Overall, the vast majority of modeling studies utilized a deterministic compartmental susceptible-infected-susceptible structure, with select studies utilizing individual-based network transmission models. In general, these studies found that harm reduction alone is unlikely to achieve elimination targets among PWID. However, modeling indicates elimination is achievable in a wide variety of epidemic settings with harm reduction scale-up combined with modest levels of HCV treatment for PWID. Unfortunately, current levels of testing and treatment are generally insufficient to achieve elimination in most settings, and require further scale-up. Additionally, network-based treatment strategies as well as prison-based treatment and harm reduction provision could provide important additional population benefits. Overall, epidemic modeling has and continues to play a critical role in informing HCV elimination strategies worldwide.

Intimate relationships and patterns of drug and sexual risk behaviors among people who inject drugs in Kazakhstan: A latent class analysis

BACKGROUND

Multiple drug and sexual risk behaviors among people who inject drugs (PWID) in intimate relationships increase the risk of HIV and HCV transmission. Using data on PWID in intimate partnerships in Almaty, Kazakhstan, this study performed latent class analysis (LCA) on drug and sexual risk behaviors and estimated associations between dyadic relationship factors and membership in latent classes.

METHODS

LCA was performed on a sample of 510 PWID (181-females/FWID, 321-males/MWID) to identify levels of drug and sexual risk behaviors. Generalized structural equation modeling with multinomial regressions estimated associations between relationship factors (length risk reduction communication, risk reduction self-efficacy) and class membership after adjusting for substance use severity, overdose, depression, binge drinking, intimate partner violence, structural factors, and sociodemographic characteristics. Models were sex-stratified to include FWID and PWID.

RESULTS

A 3-class model best fit the data and consisted of low, medium, and high-risk classes. GSEM found that greater injection self-efficacy was associated with a lower likelihood of membership in the high-risk class for PWID and FWID. For MWID, greater length of the relationship was associated with a lower likelihood of membership in the medium-risk class. Greater relationship communication was associated with increased risk of membership in the high-risk latent class for MWID.

CONCLUSIONS

Future research must investigate if increasing risk reduction and safe sex self-efficacy could reduce drug and sexual risk behaviors and HIV transmission among PWID and their intimate partners. Interventions are needed that reduce power inequities within relationships as a method of increasing self-efficacy, particularly among women.

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

Background

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.

Methods

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.

Results

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.

Conclusions

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.

Human immunodeficiency virus infection predictors and genetic diversity of hepatitis B virus and hepatitis C virus co-infections among drug users in three major Kenyan cities

Background

Drug users act as reservoirs and transmission channels for hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections to the general population worldwide. Periodic epidemiological studies to monitor the prevalence and genetic diversity of these infections to inform on interventions are limited.

Objective of the study

The objective of this study was to determine the predictors of HIV infection and genetic diversity of HBV and HCV among drug users in Kenya.

Materials and methods

A cross-sectional study on previous drug use history among drug users was conducted in three Kenyan cities using a respondent-driven sampling method between January 2011 and September 2012. Blood samples were collected and analysed for the presence of HBV, HCV and HIV serological markers and to determine the genotypes of HBV and HCV.

Results

The overall prevalence of HBV, HCV and HIV among drug users was 4.3%, 6.5% and 11.1%, respectively, with evidence of HBV/HIV, HCV/HIV and HBV/HCV/HIV co-infections. The HBV circulating genotypes were A1 (69%) and D6 (19%), whereas HCV genotypes were 1a (72%) and 4a (22%). Injection drug use was a significant predictor of HIV/HCV infections. Younger age (30 years; aOR (adjusted odds ratio) = 0.50, 95% CI (confidence interval): 0.33–0.76; p < 0.001) and early sexual debut (aOR = 0.54, 95% CI: 0.40–0.82; p < 0.05) were negatively associated with detection of any of the three infections. Injecting drug use was positively associated with HCV infection (aOR = 5.37, 95% CI: 2.61–11.06; p < 0.001).

Conclusion

This high level of genetic diversity exhibited by HBV and HCV isolates requires urgent implementation of harm reduction strategies and continuous monitoring for effective management of the patients.

Sex Work as an Emerging Risk Factor for Human Immunodeficiency Virus Seroconversion Among People who Inject Drugs in the SurvUDI Network

BACKGROUND

Recent analyses have shown an emerging positive association between sex work and human immunodeficiency virus (HIV) incidence among people who inject drugs (PWIDs) in the SurvUDI network.

METHODS

Participants who had injected in the past 6 months were recruited across the Province of Quebec and in the city of Ottawa, mainly in harm reduction programs. They completed a questionnaire and provided gingival exudate for HIV antibody testing. The associations with HIV seroconversion were tested with a Cox proportional hazard model using time-dependent covariables including the main variable of interest, sexual activity (sex work; no sex work; sexually inactive). The final model included significant variables and confounders of the associations with sexual activity.

RESULTS

Seventy-two HIV seroconversions were observed during 5239.2 person-years (py) of follow-up (incidence rates: total = 1.4/100 py; 95% confidence interval [CI], 1.1-1.7; sex work = 2.5/100 py; 95% CI, 1.5-3.6; no sex work = 0.8/100 py; 95% CI, 0.5-1.2; sexually inactive = 1.8/100 py; 95% CI, 1.1-2.5). In the final multivariate model, HIV incidence was significantly associated with sexual activity (sex work: adjusted hazard ratio [AHR], 2.19; 95% CI, 1.13-4.25; sexually inactive: AHR, 1.62; 95% CI, 0.92-2.88), and injection with a needle/syringe used by someone else (AHR, 2.84; 95% CI, 1.73-4.66).

CONCLUSIONS

Sex work is independently associated with HIV incidence among PWIDs. At the other end of the spectrum of sexual activity, sexually inactive PWIDs have a higher HIV incidence rate, likely due to more profound dependence leading to increased vulnerabilities, which may include mental illness, poverty, and social exclusion. Further studies are needed to understand whether the association between sex work and HIV is related to sexual transmission or other vulnerability factors.

HCV avidity as a tool for detection of recent HCV infection: Sensitivity depends on HCV genotype

Accurate detection of incident hepatitis C virus (HCV) infection is required to target and evaluate public health interventions, but acute infection is largely asymptomatic and difficult to detect using traditional methods. Our aim was to evaluate a previously developed HCV avidity assay to distinguish acute from chronic HCV infection. Plasma samples collected from recent seroconversion subjects in two large Australian cohorts were tested using the avidity assay, and the avidity index (AI) was calculated. Demographic and clinical characteristics of patients with low/high AI were compared via logistic regression. Sensitivity and specificity of the assay for recent infection and the mean duration of recent infection (MDRI) were estimated stratified by HCV genotype. Avidity was assessed in 567 samples (from 215 participants), including 304 with viraemia (defined as ≥250 IU/mL). An inverse relationship between AI and infection duration was found in viraemic samples only. The adjusted odds of a low AI (<30%) decreased with infection duration (odds ratio [OR] per week of 0.93; 95% CI:0.89-0.97), and were lower for G1 compared with G3 samples (OR = 0.14; 95% CI:0.05-0.39). Defining recent infection as <26 weeks, sensitivity (at AI cut-off of 20%) was estimated at 48% (95% CI:39-56%), 36% (95% CI:20-52%), and 65% (95% CI:54-75%) and MDRI was 116, 83, and 152 days for all genotypes, G1, and G3, respectively. Specificity (≥52 weeks infection duration, all genotypes) was 96% (95% CI:90-98%). HCV avidity testing has utility for detecting recent HCV infection in patients, and for assessing progress in reaching incidence targets for eliminating transmission, but variation in assay performance across genotype should be recognized.

Seroprevalence of HCV and HIV infection among clients of the nation's longest-standing statewide syringe exchange program: A cross-sectional study of Community Health Outreach Work to Prevent AIDS (CHOW)

BACKGROUND

The Community Health Outreach Work to Prevent AIDS (CHOW) Project is the first and longest-standing statewide integrated and funded needle and syringe exchange program (SEP) in the US. Initiated on O'ahu in 1990, CHOW expanded statewide in 1993. The purpose of this study is to estimate the prevalences of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infection, and to characterize risk behaviors associated with infection among clients of a long-standing SEP through the analysis of the 2012 CHOW evaluation data.

METHODS

A cross-sectional sample of 130 CHOW Project clients was selected from January 1, 2012 through December 31, 2012. Questionnaires captured self-reported exposure information. HIV and HCV antibodies were detected via rapid, point-of-care FDA-approved tests. Log-binomial regressions were used to estimate prevalence proportion ratios (PPRs). A piecewise linear log-binomial regression model containing 1 spline knot was used to fit the age-HCV relationship.

RESULTS

The estimated seroprevalence of HCV was 67.7% (95% confidence interval [CI]=59.5-75.8%). HIV seroprevalence was 2.3% (95% CI=0-4.9%). Anti-HCV prevalence demonstrated age-specific patterns, ranging from 31.6% through 90.9% in people who inject drugs (PWID) <30 to ≥60 years respectively. Age (continuous/year) prior to spline knot at 51.5 years (adjusted PPR [APPR]=1.03; 95% CI=1.02-1.05) and months exchanging syringes (quartiles) (APPR=1.92; 95% CI=1.3-3.29) were independently associated with anti-HCV prevalence.

CONCLUSION

In Hawai'i, HCV prevalence among PWID is hyperendemic demonstrating age- and SEP duration-specific trends. Relatively low HIV prevalence compared with HCV prevalence reflects differences in transmissibility of these 2 blood-borne pathogens and suggests much greater efficacy of SEP for HIV prevention.

Racial/Ethnic Disparities at the End of an HIV Epidemic: Persons Who Inject Drugs in New York City, 2011-2015

OBJECTIVES

To examine whether racial/ethnic disparities persist at the "end of the HIV epidemic" (prevalence of untreated HIV infection < 5%; HIV incidence < 0.5 per 100 person-years) among persons who inject drugs (PWID) in New York City.

METHODS

We recruited 2404 PWID entering New York City substance use treatment in 2001 to 2005 and 2011 to 2015. We conducted a structured interview, and testing for HIV and herpes simplex virus 2 (HSV-2; a biomarker for high sexual risk). We estimated incidence by using newly diagnosed cases of HIV. Disparity analyses compared HIV, untreated HIV, HIV-HSV-2 coinfection, HIV monoinfection, and estimated HIV incidence among Whites, African Americans, and Latinos.

RESULTS

By 2011 to 2015, Whites, African Americans, and Latino/as met both criteria of our operational "end-of-the-epidemic" definition. All comparisons that included HIV-HSV-2-coinfected persons had statistically significant higher rates of HIV among racial/ethnic minorities. No comparisons limited to HIV monoinfected persons were significant.

CONCLUSIONS

"End-of-the-epidemic" criteria were met among White, African American, and Latino/a PWID in New York City, but elimination of disparities may require a greater focus on PWID with high sexual risk.

HCV prevalence and risk behaviours among injectors of new psychoactive substances in a risk environment in Hungary-An expanding public health burden

BACKGROUND

In Hungary a large increase in injecting new psychoactive substances (NPS) coincided with decreasing harm reduction efforts and rising HCV infection. We describe these, and assess changes in HCV prevalence and risk behaviours, 2011-2014, among NPS injectors, using 2011-2015 syringe exchange programme (SEP) data as a key contextual ('risk environment') variable.

METHODS

We conducted repeated national sero-behavioural surveys in people who inject drugs (PWID) injecting in the last month and attending SEPs or drug treatment centres (n=399, 2011; 384, 2014), using face-to-face interviews and dried blood-spot samples. Prevalence of injected drugs and SEP coverage (2011-2015) were assessed through our national SEP monitoring system and using population size estimates.

RESULTS

NPS injecting tripled among PWID attending SEPs in Hungary (2011: 26%; 2015: 80%). Among NPS injectors, HCV prevalence, sharing syringes and sharing any injecting equipment (last month), doubled (2011-2014: 37%-74%, 20%-48%, 42%-71%, respectively), significantly exceeding prevalence in other PWID groups. Among young NPS injectors (aged<25), HCV prevalence increased 7-fold (12%-76%), among new injectors (injecting<2years) 4-fold (13%-42%), coupled with high levels of equipment sharing (79% and 72% respectively). Not using a condom at last intercourse (79%), ever-imprisonment (65%) and last-year homelessness (57%) were highly prevalent among NPS injectors (2014). The number of syringes distributed per estimated PWID nationally fell from 114 to 81 (2011-2014) and dropped to 28 in 2015.

CONCLUSION

NPS injectors in Hungary are at severe risk of blood-borne infections due to high levels of injecting and sexual risk behaviours within a high-risk environment, including continuously low SEP provision, imprisonment and homelessness. An HIV outbreak cannot be excluded. Stronger investment in evidence-based prevention measures, with special focus on young and new injectors, and expansion of hepatitis C treatment are urgently needed.

Estimating the burden of disease attributable to injecting drug use as a risk factor for HIV, hepatitis C, and hepatitis B: findings from the Global Burden of Disease Study 2013

BACKGROUND

Previous estimates of the burden of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) among people who inject drugs have not included estimates of the burden attributable to the consequences of past injecting. We aimed to provide these estimates as part of the Global Burden of Disease (GBD) Study 2013.

METHODS

We modelled the burden of HBV and HCV (including cirrhosis and liver cancer burden) and HIV at the country, regional, and global level. We extracted United Nations data on the proportion of notified HIV cases by transmission route, and estimated the contribution of injecting drug use (IDU) to HBV and HCV disease burden by use of a cohort method that recalibrated individuals' history of IDU, and accumulated risk of HBV and HCV due to IDU. We estimated data on current IDU from a meta-analysis of HBV and HCV incidence among injecting drug users and country-level data on the incidence of HBV and HCV between 1990 and 2013. We calculated estimates of burden of disease through years of life lost (YLL), years of life lived with disability (YLD), deaths, and disability-adjusted life-years (DALYs), with 95% uncertainty intervals (UIs) calculated for each metric.

FINDINGS

In 2013, an estimated 10·08 million DALYs were attributable to previous exposure to HIV, HBV, and HCV via IDU, a four-times increase since 1990. In total in 2013, IDU was estimated to cause 4·0% (2·82 million DALYs, 95% UI 2·4 million to 3·8 million) of DALYs due to HIV, 1·1% (216 000, 101 000-338 000) of DALYs due to HBV, and 39·1% (7·05 million, 5·88 million to 8·15 million) of DALYs due to HCV. IDU-attributable HIV burden was highest in low-to-middle-income countries, and IDU-attributable HCV burden was highest in high-income countries.

INTERPRETATION

IDU is a major contributor to the global burden of disease. Effective interventions to prevent and treat these important causes of health burden need to be scaled up.

FUNDING

Bill & Melinda Gates Foundation and Australian National Health and Medical Research Council.

HIV Risk Behavior Among Methamphetamine Users Entering Substance Abuse Treatment in Cape Town, South Africa

South Africa is experiencing a growing methamphetamine problem, and there is concern that methamphetamine use may accelerate HIV transmission. There has been little research on the HIV prevention needs of methamphetamine users receiving substance abuse treatment in South Africa. This study assessed the prevalence and correlates of HIV risk behaviors among 269 methamphetamine users entering substance abuse treatment in two clinics in Cape Town. The prevalence of sexual risk behaviors was high among sexually active participants: 34 % multiple partners, 26 % unprotected intercourse with a casual partner, and 24 % sex trading for money/methamphetamine. The strongest predictor of all sexual risk behaviors was concurrent other drug use. Over half had not been HIV tested in the past year, and 25 % had never been tested, although attitudes toward HIV testing were overwhelmingly positive. This population of primarily heterosexual, non-injecting methamphetamine users is a high-risk group in need of targeted HIV prevention interventions. Substance abuse treatment is an ideal setting in which to reach methamphetamine users for HIV services.

Overlapping substance using high-risk groups and infectious diseases: how dynamic modelling can evaluate risk and target HIV prevention

It’s difficult to develop infectious disease interventions (such as for HIV) for overlapping high-risk populations such as people who inject drugs, men who have sex with men, and female sex workers, where there are multiple transmission routes. Recent advances in dynamic modelling of coinfection epidemics could disentangle the contributions of different risk groups and behaviours to help develop more efficient and effective prevention interventions.

T Cell Distribution in Relation to HIV/HBV/HCV Coinfections and Intravenous Drug Use

Intravenous drug use (IDU) is one of the most important transmission routes for blood borne viruses, including human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). These infections alter the subset distributions of T cells; however, knowledge of such effects during HIV, HBV, and or HCV coinfection is limited. Therefore, we aimed to evaluate any associations between T cell distribution and the presence of HIV, HBV, and HCV coinfections among persons who inject drugs (PWID). Blood samples from 88 Caucasian PWID (mean age 30; 82% male) and 47 age-matched subjects negative for all three infections (mean age of 29; 83% male) were analyzed. The T cell markers CD3, CD4, CD8, CD45RA, CCR7, HLA-DR, and CCR5 were assessed using flow cytometry. Of the PWID, 40% were HIV+HBV+HCV+, 20% HBV+HCV+, 19% HCV+, and 13% negative for all three infections. The HIV+HBV+HCV+ PWID had lower percentages of CD4⁺ and higher percentages of CD8⁺ cells compared to triple negative PWID (p < 0.001 in all cases). The only difference between HBV+HCV+ with triple negative PWID was the lower CD4⁺ cell percentages among the former (52.1% and 58.6%, p = 0.021). Triple negative PWID had higher immune activation and number of CCR5⁺ cells compared to the controls. We suggest that the altered T cell subset distribution among PWID is mainly triggered by HIV infection and or IDU, while HBV and or HCV seropositivity has minimal additional effects on CD4⁺ cell distribution.

HCV/HIV coinfection among people who inject drugs and enter opioid substitution treatment in Greece: prevalence and correlates

Background

HCV/HIV coinfection in people who inject drugs is a public health issue, which presents a variety of challenges to healthcare providers. The determinants of HCV/HIV coinfection in this population are nonetheless not well known. The aim of the present study is to identify the factors associated with HCV/HIV coinfection in people who inject drugs and enter drug-related treatment.

Methods

Linked serological and behavioral data were collected from people who entered 38 opioid substitution treatment clinics in central and southern Greece between January and December 2013. Three mutually exclusive groups were defined based on the presence of HCV and HIV antibodies. Group 1 clients had neither infection, Group 2 had HCV but not HIV, and Group 3 had HCV/HIV coinfection. Multinomial logistic regression analyses identified differences between groups according to socio-demographic, drug use and higher-risk behavioral characteristics.

Results

Our study population consisted of 580 people who injected drugs in the past 12 months (79.8 % males, with median age 36 years).79.4 % were HCV and 15.7 % HIV infected. Of those with complete serological data in both HCV and HIV indicators, 20.4 % were uninfected, 64.0 % HCV monoinfected, and 14.9 % HCV/HIV coinfected. HCV infection with or without HIV coinfection was positively associated with living alone or with a spouse/partner without children, prior incarceration, drug injecting histories of ≥10 years, and syringe sharing in the past 12 months, and negatively associated with never having previously been tested for HCV. HCV/HIV coinfection, but not HCV infection alone, was positively associated with residence in urban areas (relative risk ratio [RRR] = 4.8, 95 % confidence interval [CI]: 1.7–13.7, p = 0.004) and averaging >3 injections a day in the past 30 days (RRR = 4.5, 95 % CI: 1.6–12.8, p = 0.005), and negatively associated with using a condom in the last sexual intercourse.

Conclusions

People who inject drugs and live in urban areas and inject frequently have higher risk of coinfection. Findings highlight the need for scaling-up needle and syringe programs in inner city areas and promoting access of this population to screening and treatment, especially in prisons. The protective role of living with parents and children could inform the implementation of indicated interventions.

Prevalence and burden of HCV co-infection in people living with HIV: a global systematic review and meta-analysis

BACKGROUND

At global level, there are 37 million people infected with HIV and 115 million people with antibodies to hepatitis C virus (HCV). Little is known about the extent of HIV-HCV co-infection. We sought to characterise the epidemiology and burden of HCV co-infection in people living with HIV.

METHODS

In this systematic review and meta-analysis we searched MEDLINE, Embase, CINAHL+, POPLINE, Africa-wide Information, Global Health, Web of Science, and the Cochrane Library and WHO databases for studies measuring prevalence of HCV and HIV, published between Jan 1, 2002, and Jan 28, 2015. We included studies in HIV population samples of more than 50 individuals and recruited patients based on HIV infection status or other behavioural characteristics. We excluded editorials or reviews containing no primary data, samples of HCV or HIV-HCV co-infected individuals, or samples relying on self-reported infection status. We also excluded samples drawn from populations with other comorbidities or undergoing interventions that put them at increased risk of co-infection. Populations were categorised according to HIV exposure, with the regional burden of co-infection being derived by applying co-infection prevalence estimates to published numbers of HIV-infected individuals. We did a meta-analysis to estimate the odds of HCV in HIV-infected individuals compared with their HIV-negative counterparts.

FINDINGS

From 31 767 citations identified, 783 studies met the inclusion criteria, resulting in 902 estimates of the prevalence of HIV-HCV co-infection. In HIV-infected individuals, HIV-HCV co-infection was 2·4% (IQR 0·8-5·8) within general population samples, 4·0% (1·2-8·4) within pregnant or heterosexually exposed samples, 6·4% (3·2-10·0) in men who have sex with men (MSM), and 82·4% (55·2-88·5) in people who inject drugs (PWID). Odds of HCV infection were six times higher in people living with HIV (5·8, 95% CI 4·5-7·4) than their HIV-negative counterparts. Worldwide, there are approximately 2 278 400 HIV-HCV co-infections (IQR 1 271 300-4 417 000) of which 1 362 700 (847 700-1 381 800) are in PWID, equalling an overall co-infection prevalence in HIV-infected individuals of 6·2% (3·4-11·9).

INTERPRETATION

We noted a consistently higher HCV prevalence in HIV-infected individuals than HIV-negative individuals  across all risk groups and regions, but especially in PWID. This study highlights the importance of routine HCV testing in all HIV-infected individuals, but especially in PWID. There is also a need to improve country-level surveillance of HCV prevalence across different population groups in all regions.

FUNDING

WHO.

Public health and international drug policy

In September 2015, the member states of the United Nations endorsed sustainable development goals (SDG) for 2030 that aspire to human rights-centered approaches to ensuring the health and well-being of all people. The SDGs embody both the UN Charter values of rights and justice for all and the responsibility of states to rely on the best scientific evidence as they seek to better humankind. In April 2016, these same states will consider control of illicit drugs, an area of social policy that has been fraught with controversy, seen as inconsistent with human rights norms, and for which scientific evidence and public health approaches have arguably played too limited a role.

The previous UN General Assembly Special Session (UNGASS) on drugs in 1998 – convened under the theme “a drug-free world, we can do it!” – endorsed drug control policies based on the goal of prohibiting all use, possession, production, and trafficking of illicit drugs. This goal is enshrined in national law in many countries. In pronouncing drugs a “grave threat to the health and well-being of all mankind,” the 1998 UNGASS echoed the foundational 1961 convention of the international drug control regime, which justified eliminating the “evil” of drugs in the name of “the health and welfare of mankind.” But neither of these international agreements refers to the ways in which pursuing drug prohibition itself might affect public health. The “war on drugs” and “zero-tolerance” policies that grew out of the prohibitionist consensus are now being challenged on multiple fronts, including their health, human rights, and development impact.

The Johns Hopkins – Lancet Commission on Drug Policy and Health has sought to examine the emerging scientific evidence on public health issues arising from drug control policy and to inform and encourage a central focus on public health evidence and outcomes in drug policy debates, such as the important deliberations of the 2016 UNGASS on drugs.

The Johns Hopkins-Lancet Commission is concerned that drug policies are often colored by ideas about drug use and drug dependence that are not scientifically grounded. The 1998 UNGASS declaration, for example, like the UN drug conventions and many national drug laws, does not distinguish between drug use and drug abuse. A 2015 report by the UN High Commissioner for Human Rights, by contrast, found it important to emphasize that “[d]rug use is neither a medical condition nor does it necessarily lead to drug dependence.” The idea that all drug use is dangerous and evil has led to enforcement-heavy policies and has made it difficult to see potentially dangerous drugs in the same light as potentially dangerous foods, tobacco, alcohol for which the goal of social policy is to reduce potential harms.

Injecting drug use: A vector for the introduction of new hepatitis C virus genotypes

Hepatitis C virus (HCV) genotypes’ monitoring allows real-time insight into the dynamic changes that occur in the global epidemiological picture of HCV infection. Intravenous drug use is currently the primary driver for HCV transmission in developed and developing countries. The distribution of HCV genotypes/subtypes differs significantly between people who inject drugs (PWID) and the general population. HCV genotypes that previously exhibited a limited geographical distribution (3a, 4) are becoming more prevalent in this high-risk group. Immigration from HCV-endemic countries and the evolving networks of HCV transmission in PWID influence HCV genotypes distribution in Europe. Social vulnerabilities (e.g., unemployment, homelessness, and limited access to social and healthcare insurances systems) are important triggers for illicit drug use, which increases the associated risks of HCV infection and the frequent emergence of less prevalent genotypes. Genotype/subtype determination bears important clinical consequences in the progression of liver disease, susceptibility to antiviral therapies and the emergence of resistance-associated variants. An estimated half of the chronically HCV-infected PWID are unaware of their infection, and only one in ten of those diagnosed enter treatment. Nevertheless, PWID exhibit high response rates to new antiviral regimens, and the level of HCV reinfection is unexpectedly low. The focus of the healthcare system must be on the early detection and treatment of infection, to avoid late presentations that are associated with high levels of viremia and liver fibrosis, which may diminish the therapeutic success rate.

Treatment of Acute Hepatitis C Infection with Pegylated Interferon and Ribavirin in Patients Coinfected with Human Immunodeficiency Virus: A Systematic Review and Meta-Analysis

BACKGROUND/AIMS

Of the 35 million human immunodeficiency virus (HIV)-positive patients worldwide, 10-40% are coinfected with chronic hepatitis C virus (HCV). Compared to HCV-monoinfected patients, those coinfected experience decreased spontaneous HCV clearance, accelerated liver fibrosis, and a decreased response to anti-HCV therapy. We conducted a meta-analysis to estimate the efficacy of treating acute HCV in HIV-positive patients with peginterferon and ribavirin combination therapy.

METHODS

Two authors independently searched MEDLINE and EMBASE (2014) for English articles, and reviewed bibliographies and abstracts from major liver and HIV conferences (2011-2013). Original studies featuring at least 10 treatment-naive, HIV-positive adults infected with acute HCV and treated with peginterferon and ribavirin were included. Analyses were calculated using a random-effects model. Heterogeneity was assessed using the Cochrane Q test (p < 0.05) and the I(2) statistic (>50%).

RESULTS

From 12 studies (450 patients), the pooled sustained virological response (SVR) was 71.4% (95% CI 64.7-77.4; Q statistic = 22.20, p = 0.023, I(2) = 50.44). The rapid virological response (RVR; 7 studies, 196 patients) was 47.4% (95% CI 40.6-54.7), and the early virological response (EVR; 9 studies, 283 patients) was 82.8% (95% CI 67.0-92.0). The probability of an SVR was 93.1% (95% CI 84.9-97.0) in those who obtained an RVR (6 studies, 82 patients) and 85.9% (95% CI 78.7-91.0) if an EVR (7 studies, 168 patients) was reached.

CONCLUSION

Peginterferon with ribavirin is an effective option for treating acute HCV in HIV-positive patients, especially if they achieve an RVR or an EVR.

Modeling hepatitis C virus transmission among people who inject drugs: Assumptions, limitations and future challenges

The discovery of highly effective hepatitis C virus (HCV) treatments has led to discussion of elimination and intensified interest in models of HCV transmission. In developed settings, HCV disproportionally affects people who inject drugs (PWID), and models are typically used to provide an evidence base for the effectiveness of interventions such as needle and syringe programs, opioid substitution therapy and more recently treating PWID with new generation therapies to achieve specified reductions in prevalence and / or incidence. This manuscript reviews deterministic compartmental S-I, deterministic compartmental S-I-S and network-based transmission models of HCV among PWID. We detail typical assumptions made when modeling injecting risk behavior, virus transmission, treatment and re-infection and how they correspond with available evidence and empirical data.

Global Epidemiology of HIV Among Women and Girls Who Use or Inject Drugs: Current Knowledge and Limitations of Existing Data

BACKGROUND

Women and girls who use and inject drugs are a critical population at risk of HIV. In this article, we review data on the epidemiology of drug use and injection among women globally and HIV prevalence among women and girls who use and inject drugs.

RESULTS

Women and girls comprise one-third of people who use and inject drugs globally. There is substantial variation in HIV prevalence in this population, between and within countries. There is a pronounced lack of data examining HIV risk among particularly vulnerable subpopulations of women who use and inject drugs, including women who have sex with women, transgender women, racial and ethnic minority women, and young women. Women who use and inject drugs experience stigma and discrimination that affect access to services, and high levels of sexual risk exposures.

CONCLUSIONS

There are significant gaps in our understanding of the epidemiology of drug use and injecting among women and girls and HIV risk and prevalence in this population. Women are frequently underrepresented in studies of drug use and HIV risk and prevalence among people who inject drugs, limiting our understanding of possible sex differences in this population. Most research originates from developed countries and may not be generalizable to other settings. A great deal of work is needed to improve understanding of HIV among particularly vulnerable subpopulations, such as transgender women who use drugs. Better data are critical to efforts to advocate for the needs of women and girls who use and inject drugs.

Human rights and access to hepatitis C treatment for people who inject drugs

BACKGROUND

People who inject drugs (PWID) achieve adherence to and outcomes from hepatitis C virus (HCV) treatment comparable to other patients. Nonetheless, this population has been excluded from treatment by regulation or practice. Approval of safer and more effective oral HCV medicines should offer greater treatment options for PWID, although high medicine prices have led to continued treatment rationing and exclusion in developed countries. In middle-income countries (MICS), treatment is largely unavailable and unaffordable for most PWID.

METHODS

Human rights analysis, with its emphasis on the universal and interconnected nature of the economic, social and political spheres, offers a useful framework for HCV treatment reform. Using peer-reviewed and grey literature, as well as community case reports, we discuss barriers to treatment, correlate these barriers to rights violations, and highlight examples of community advocacy to increase treatment for PWID.

RESULTS

Structural drivers of lack of treatment access for PWID include stigma in health settings; drug use status as a criterion for treatment exclusion; requirements for fees or registration by name as a drug user prior to treatment initiation; and incarceration/detention in prisons and rehabilitation centers where treatment is unavailable. High medicine prices force further exclusion of PWID, with cost containment masked as concern about treatment adherence. These barriers correlate to multiple rights violations, including of the rights to privacy; non-discrimination; health; freedom of information; fair trial; and freedom from cruel, inhuman and degrading treatment.

CONCLUSIONS

Needed reforms include decriminalization of drug use, possession of drugs and drug injecting equipment; removal of exclusionary or discriminatory treatment protocols; approaches to strengthen links between health providers and increase participation of PWID in treatment design and implementation; and measures to increase transparency in government/pharmaceutical company negotiations and reduce treatment price.

Will "Combined Prevention" Eliminate Racial/Ethnic Disparities in HIV Infection among Persons Who Inject Drugs in New York City?

It has not been determined whether implementation of combined prevention programming for persons who inject drugs reduce racial/ethnic disparities in HIV infection. We examine racial/ethnic disparities in New York City among persons who inject drugs after implementation of the New York City Condom Social Marketing Program in 2007. Quantitative interviews and HIV testing were conducted among persons who inject drugs entering Mount Sinai Beth Israel drug treatment (2007–2014). 703 persons who inject drugs who began injecting after implementation of large-scale syringe exchange were included in the analyses. Factors independently associated with being HIV seropositive were identified and a published model was used to estimate HIV infections due to sexual transmission. Overall HIV prevalence was 4%; Whites 1%, African-Americans 17%, and Hispanics 4%. Adjusted odds ratios were 21.0 (95% CI 5.7, 77.5) for African-Americans to Whites and 4.5 (95% CI 1.3, 16.3) for Hispanics to Whites. There was an overall significant trend towards reduced HIV prevalence over time (adjusted odd ratio = 0.7 per year, 95% confidence interval (0.6–0.8). An estimated 75% or more of the HIV infections were due to sexual transmission. Racial/ethnic disparities among persons who inject drugs were not significantly different from previous disparities. Reducing these persistent disparities may require new interventions (treatment as prevention, pre-exposure prophylaxis) for all racial/ethnic groups.

Increasing prevalence of HIV infection among first time clients in Italian drug treatment services - is it sexual transmission?

BACKGROUND

Over the last two decades, the proportion of people who inject drugs among newly reported HIV cases in Italy has been continuously declining. This trend is reflected in the prevalence of HIV infection among problem drug users followed in drug treatment services. We report nationwide trends in the prevalence of HIV and HCV among tested clients in charge to drug addiction services from 2005 to 2011.

METHODS

Data on the prevalence of HIV and HCV among drug users from public drug treatment services across Italy were collected and analyzed for the period from 2005 to 2011. Prevalence of HIV and HCV were compared between clients returning to treatment and those entering treatment for the first time, and by gender. Due to the high percentage of missing data, the "inverse probability weight" method was used. Trends in testing uptake were also analysed.

RESULTS

A significant decrease of HIV and HCV prevalence is observed among all PDUs entering treatment (from 14.7% to 11.1% and from 61.6% to 50%, respectively, in 2005-2011). By contrast, among those entering the services for the first time, after an initial decline the prevalence of HIV infection steadily increased in both sexes, from 2.2% in 2009 to 5.3% in 2011. Self-reported injecting rates in this group decreased over time, and in 2011 the proportion reporting drug injecting was lower among new clients than in people returning to services (14.5 vs. 34.4%). We also observed a progressive and significant reduction in HIV and HCV testing in drug treatment services.

CONCLUSIONS

Changes in injection practice and type of drugs used, coupled with a concurrent reduction in HCV prevalence, do not support drug injection as the main explanation for an increased HIV transmission in people entering drug treatment services for the first time. While reductions in testing rates raise concerns over data quality, the possibility of increased sexual transmission needs to be considered.

Modeling the effect of HIV coinfection on clearance and sustained virologic response during treatment for hepatitis C virus

BACKGROUND

HIV/hepatitis C (HCV) coinfection is a major concern in global health today. Each pathogen can exacerbate the effects of the other and affect treatment outcomes. Understanding the within-host dynamics of these coinfecting pathogens is crucial, particularly in light of new, direct-acting antiviral agents (DAAs) for HCV treatment that are becoming available.

METHODS AND FINDINGS

In this study, we construct a within-host mathematical model of HCV/HIV coinfection by adapting a previously published model of HCV monoinfection to include an immune system component in infection clearance. We explore the effect of HIV-coinfection on spontaneous HCV clearance and sustained virologic response (SVR) by building in decreased immune function with increased HIV viral load. Treatment is modeled by modifying HCV burst-size, and we use clinically-relevant parameter estimates. Our model replicates real-world patient outcomes; it outputs infected and uninfected target cell counts, and HCV viral load for varying treatment and coinfection scenarios. Increased HIV viral load and reduced CD4(+) count correlate with decreased spontaneous clearance and SVR chances. Treatment efficacy/duration combinations resulting in SVR are calculated for HIV-positive and negative patients, and crucially, we replicate the new findings that highly efficacious DAAs reduce treatment differences between HIV-positive and negative patients. However, we also find that if drug efficacy decays sufficiently over treatment course, SVR differences between HIV-positive and negative patients reappear.

CONCLUSIONS

Our model shows theoretical evidence of the differing outcomes of HCV infection in cases where the immune system is compromised by HIV. Understanding what controls these outcomes is especially important with the advent of efficacious but often prohibitively expensive DAAs. Using a model to predict patient response can lend insight into optimal treatment design, both in helping to identify patients who might respond well to treatment and in helping to identify treatment pathways and pitfalls.

HIV and HCV coinfection: prevalence, associated factors and genotype characterization in the Midwest Region of Brazil

A cross-sectional study on prevalence, associated factors and genotype distribution of HCV infection was conducted among 848 HIV-infected patients recruited at reference centers in the Midwest Region of Brazil. The prevalence rate of HIV-HCV coinfection was 6.9% (95% CI: 5.2 to 8.6). In multivariable analysis, increasing age, use of illicit drugs (injection and non-injection), a history of blood transfusion before 1994, and the absence of a steady partnership were significant independent associated factors for HIV-HCV coinfection. The phylogenetic analysis based on the NS5B region revealed the presence of two major circulating genotypes of HCV: genotypes 1 (58.3%) and 3 (41.7%). The prevalence of HIV-HCV coinfection was lower than those reported in studies conducted with HIV-infected patients in different regions of Brazil, due to the fact that illicit drug use is not a frequent mode of HIV transmission in this region of Brazil. Serologic screening of HIV-patients for HCV before initiating antiretroviral treatment, a comprehensive identification of associated factors, and the implementation of effective harm reduction programs are highly recommended to provide useful information for treatment and to prevent HCV coinfection in these patients.

Is the promise of methadone Kenya's solution to managing HIV and addiction? A mixed-method mathematical modelling and qualitative study

BACKGROUND AND OBJECTIVES

Promoted globally as an evidence-based intervention in the prevention of HIV and treatment of heroin addiction among people who inject drugs (PWID), opioid substitution treatment (OST) can help control emerging HIV epidemics among PWID. With implementation in December 2014, Kenya is the third Sub-Saharan African country to have introduced OST. We combine dynamic mathematical modelling with qualitative sociological research to examine the 'promise of methadone' to Kenya.

METHODS, SETTING AND PARTICIPANTS

We model the HIV prevention impact of OST in Nairobi, Kenya, at different levels of intervention coverage. We draw on thematic analyses of 109 qualitative interviews with PWID, and 43 with stakeholders, to chart their narratives of expectation in relation to the promise of methadone.

RESULTS

The modelled impact of OST shows relatively slight reductions in HIV incidence (5-10%) and prevalence (2-4%) over 5 years at coverage levels (around 10%) anticipated in the planned roll-out of OST. However, there is a higher impact with increased coverage, with 40% coverage producing a 20% reduction in HIV incidence, even when accounting for relatively high sexual transmissions. Qualitative findings emphasise a culture of 'rationed expectation' in relation to access to care and a 'poverty of drug treatment opportunity'. In this context, the promise of methadone may be narrated as a symbol of hope-both for individuals and community-in relation to addiction recovery.

CONCLUSIONS

Methadone offers HIV prevention potential, but there is a need to better model the effects of sexual HIV transmission in mediating the impact of OST among PWID in settings characterised by a combination of generalised and concentrated epidemics. We find that individual and community narratives of methadone as hope for recovery coexist with policy narratives positioning methadone primarily in relation to HIV prevention. Our analyses show the value of mixed methods approaches to investigating newly-introduced interventions.

Dynamic modelling of hepatitis C virus transmission among people who inject drugs: a methodological review

Equipment sharing among people who inject drugs (PWID) is a key risk factor in infection by hepatitis C virus (HCV). Both the effectiveness and cost-effectiveness of interventions aimed at reducing HCV transmission in this population (such as opioid substitution therapy, needle exchange programmes or improved treatment) are difficult to evaluate using field surveys. Ethical issues and complicated access to the PWID population make it difficult to gather epidemiological data. In this context, mathematical modelling of HCV transmission is a useful alternative for comparing the cost and effectiveness of various interventions. Several models have been developed in the past few years. They are often based on strong hypotheses concerning the population structure. This review presents compartmental and individual-based models to underline their strengths and limits in the context of HCV infection among PWID. The final section discusses the main results of the papers.

Potential for human immunodeficiency virus parenteral transmission in the Middle East and North Africa: An analysis using hepatitis C virus as a proxy biomarker

The Middle East and North Africa (MENA) region has endured several major events of infection parenteral transmission. Recent work has established the utility of using hepatitis C virus (HCV) as a proxy biomarker for assessing the epidemic potential for human immunodeficiency virus (HIV) parenteral transmission. In this review, we use data on the prevalence of HCV infection antibody (seroprevalence) among general population and high risk population groups to assess the potential for HIV parenteral transmission in MENA. Relatively low prevalence of HCV infection in the general population groups was reported in most MENA countries indicating that parenteral HIV transmission at endemic levels does not appear to be a cause for concern. Nonetheless, there could be opportunities for localized HIV outbreaks and transmission of other blood-borne infections in some settings such as healthcare facilities. Though there have been steady improvements in safety measures related to parenteral modes of transmission in the region, these improvements have not been uniform across all countries. More precautions, including infection control training programs, surveillance systems for nosocomial infections and wider coverage and evaluation of hepatitis B virus immunization programs need to be implemented to avoid the unnecessary spread of HIV, HCV, and other blood-borne pathogens along the parenteral modes of transmission.

The geographic distribution patterns of HIV-, HCV- and co-infections among drug users in a national methadone maintenance treatment program in Southwest China

Background

HIV-, HCV- and HIV/HCV co-infections among drug users have become a rapidly emerging global public health problem. In order to constrain the dual epidemics of HIV/AIDS and drug use, China has adopted a methadone maintenance treatment program (MMTP) since 2004. Studies of the geographic heterogeneity of HIV and HCV infections at a local scale are sparse, which has critical implications for future MMTP implementation and health policies covering both HIV and HCV prevention among drug users in China. This study aimed to characterize geographic patterns of HIV and HCV prevalence at the township level among drug users in a Yi Autonomous Prefecture, Southwest of China.

Methods

Data on demographic and clinical characteristics of all clients in the 11 MMTP clinics of the Yi Autonomous Prefecture from March 2004 to December 2012 were collected. A GIS-based geographic analysis involving geographic autocorrelation analysis and geographic scan statistics were employed to identify the geographic distribution pattern of HIV-, HCV- and co-infections among drug users.

Results

A total of 6690 MMTP clients was analyzed. The prevalence of HIV-, HCV- and co-infections were 25.2%, 30.8%, and 10.9% respectively. There were significant global and local geographic autocorrelations for HIV-, HCV-, and co-infection. The Moran’s I was 0.3015, 0.3449, and 0.3155, respectively (P < 0.0001). Both the geographic autocorrelation analysis and the geographic scan statistical analysis showed that HIV-, HCV-, and co-infections in the prefecture exhibited significant geographic clustering at the township level. The geographic distribution pattern of each infection group was different.

Conclusion

HIV-, HCV-, and co-infections among drug users in the Yi Autonomous Prefecture all exhibited substantial geographic heterogeneity at the township level. The geographic distribution patterns of the three groups were different. These findings imply that it may be necessary to inform or invent site-specific intervention strategies to better devote currently limited resource to combat these two viruses.