High HIV and hepatitis C prevalence amongst injecting drug users in Mauritius: findings from a population size estimation and respondent driven sampling survey

Background

Mauritius, an Indian Ocean Island nation of approximately 1,000,000 people, has a large number of injecting drug users (IDUs), many of whom are infected with HIV and HCV. Mauritius has been expanding harm reduction and HIV services based in the belief that HIV prevalence amongst IDUs is somewhere between 30 and 60% and the IDU population size is around 20,000. In 2009, the government of Mauritius conducted a survey to estimate the infection prevalence and risk factors and to estimate the population size of IDUs in order to more effectively expand programmes.

Methods

Men and women aged >15 years living in Mauritius and injecting illicit drugs in the past three months were recruited using respondent driven sampling (RDS). Consenting participants were interviewed about HIV-risk behaviours and tested for HIV, syphilis, HCV and HBV. Six multipliers were collected from service data and by the ‘unique identifier’ method in conjunction with the RDS survey. Proportions were calculated using the RDS analysis tool.

Results

511 IDUs enrolled in the survey; 61.2% reported injecting 2-3 times/day and 29.3% reported past month injection with a previously used needle. Amongst the 60% of IDUs who reported having sexual intercourse in the past three months, 39.5% did so with ≥2 partners. Almost all IDUs (98.1%) reported inconsistent condom use in the past 12 months. HIV prevalence was 47.4%, HCV 97.3%, HBV 9.0%, and syphilis 2.7%; 99.7% of those infected with HIV were also infected with HCV. Our population size estimates put the number of IDUs in Mauritius at around 9500, lower than previous estimates.

Conclusions

We observed high rates of HCV and HIV infection amongst IDUs in Mauritius. The scale up of targeted HCV and HIV prevention, care and treatment services for IDUs should be a high priority.     

Treatment costs of hepatitis C infection among injection drug users in Canada, 2006-2026

Background

Canadian injection drug users (IDUs) are at high risk of hepatitis C virus infection (HCV). However, little is known about the costs associated with their HCV-related medical treatment. We estimated the medical costs of treating HCV-infected IDUs from 2006 to 2026.

Methods

We employed a Markov model of entry through birth or immigration to exposure-related behaviours or experiences, HCV infection, progression to HCV sequelae and mortality for active and ex-IDUs in Canada. We estimated direct and indirect treatment costs using data from the Ontario Case Costing Initiative (OCCI).

Result

Approximately 137,000 IDUs will suffer from HCV-related disease each year until 2026. Applying the OCCI cost data to the prevalence of HCV-related disease from 2006 to 2026 yielded an estimated cost of $3.96 billion CND to treat HCV-infected IDUs.

Conclusions

Substantial costs are associated with the treatment of HCV-related disease among Canadian IDUs. Given the lack of effective HCV prevention strategies in Canada, we must develop targeted evidence-based responses to prevent HCV transmission and ensure appropriate allocation of medical resources to meet the present and future treatment needs of HCV-infected IDUs.     

Risk of Hepatitis C virus re-infection following spontaneous viral clearance in injecting drug users: a systematic review

Background

In order to develop new ways to prevent Hepatitis C virus (HCV) transmission amongst injecting drug users (IDUs), it is necessary to fully understand the dynamics of this disease. We reviewed the evidence on three key areas of HCV transmission in this population: the rate of acute HCV infection amongst IDUs who have spontaneously resolved a previous infection, the rate of chronic HCV infection amongst IDUs who have spontaneously resolved a previous infection, and the ability of IDUs to be re-infected with either the same or a different HCV genotype.

Methods

A literature search of PUBMED (January 1950 to January 2009), EMBASE (January 1980 to January 2009) and PsycINFO (January 1967 to January 2009) for English language, primary research papers was undertaken to identify longitudinal studies examining HCV re-infection following spontaneous viral clearance amongst IDUs.

Results

The systematic review identified three studies that satisfied the inclusion and exclusion criteria. Regarding the risk of acute HCV infection amongst IDUs, the findings from the three studies were conflicting and thus provided no compelling evidence in support of an increased or decreased risk of acute infection amongst IDUs who have spontaneously resolved compared to those previously uninfected. Limited evidence was found from two studies to support a reduced risk of subsequent chronic HCV infection in those who have previously spontaneously resolved an infection. Further, two studies found IDUs who spontaneously resolved an infection can be re-infected (with comparable proportions) with either the same or a different HCV genotype.

Conclusion

The limited, and sometimes contradictory, evidence published in the worldwide literature highlights the need for more longitudinal studies of IDUs to fully understand the dynamics of the disease in this population.     

Chronic hepatitis C virus infection and increases in viral load in a prospective cohort of young, HIV-uninfected injection drug users

Background

Chronic hepatitis C (HCV) infection, defined as persistent RNA (viral load) for at least 6 months, accounts for up to 50% of all cirrhosis, end-stage liver disease and liver cancer cases. Moreover, elevated HCV viral load is consistently associated with high infectivity and poor therapy response. This study aims to identify modifiable behavioral correlates both chronic HCV infection and increases in viral load over time among injection drug users (IDUs).

Methods

Cross-sectional and longitudinal analyses were performed using self-interview and serological data from a prospective cohort study (2002-2006) among young (age 18-35), HIV-negative, HCV therapy-naïve IDUs (n = 113) from metropolitan Chicago, Illinois, USA.

Results

After adjustment for age, gender and race/ethnicity, using drugs measured or mixed in someone else's syringe (odds ratio = 2.7, 95% confidence interval: 1.1, 6.7) was associated with chronic (n = 75, 66%) versus resolved (n = 38, 34%) HCV infection status. Among chronically-infected IDUs, injecting with a new, sterile syringe infrequently (<1/2 half the time when injecting) compared to frequently (1/2 the time or more when injecting) was associated with increases in viral load over time after adjusting for age, gender, race/ethnicity and time effects.

Conclusions

Reductions in risky injection-related practices among young IDUs may ameliorate both the burden of chronic HCV infection-related liver disease and elevated viral load-related poor treatment response.     

Hospitalisation for an alcohol-related cause among injecting drug users in Scotland: Increased risk following diagnosis with hepatitis C infection

Background

The rate of hepatitis C (HCV) related liver disease progression is known to be strongly associated with alcohol consumption, yet there are very few data on alcohol use in injecting drug users (IDUs), who represent 90% of Scotland's HCV-diagnosed population. To investigate the extent of alcohol use in IDUs, we used hospitalisation with an alcohol-related diagnosis as an indicator for problematic consumption levels, and compared admission rates pre- and post-HCV diagnosis.

Methods

Data for 41,062 current/former IDUs attending drug treatment/support services in Scotland from April 1995 to March 2006 were linked to the national hospital discharge database to retrieve alcohol-related episodes, and to the national HCV Diagnosis database to determine HCV-diagnosed status. Relative risks were estimated using Cox proportional hazards regression for recurrent events.

Results

The proportion of IDUs with ≥1 alcohol-related admission following first attendance at drug services was greater among those diagnosed with HCV by the end of follow-up (16%) compared with those who were not (6%). For the 9145 IDUs who had been diagnosed with HCV by 31 March 2006, there was a 1.5-fold increased relative risk of an alcohol-related admission >30 days post-HCV diagnosis (95% CI: 1.2-1.7) compared with >30 days pre-HCV diagnosis, adjusted for sex, age, and deprivation.

Conclusions

IDUs diagnosed with HCV infection have an increased risk of subsequent hospital admission for an alcohol-related cause. Because of the synergistic effect of HCV infection and excessive alcohol intake on the development of cirrhosis, it is imperative that alcohol intake is addressed in the management of chronic HCV infection in this population.     

Performance and coverage of HIV interventions for injection drug users: Insights from triangulation of programme, field and surveillance data from Pakistan

Introduction

Nearly 20% of the estimated 84,000 injecting drug users in Pakistan are HIV infected. Non-governmental organisations have implemented HIV interventions for IDUs in 7 cities in Pakistan. Here we report on the performance, coverage and costs of these interventions.

Methods

National HIV bio-behavioural surveillance data were used to measure effectiveness of interventions by comparing HIV prevalence and behavioural trends in intervention and non-intervention cities. Coverage was measured by comparing the supply of syringes with the total syringe need and intervention cost per IDU served per year was calculated.

Results

The NGOs registered 20,640 IDUs (original targets: <10,000); provided 66% of new syringes for all registered IDUs and 75% for all estimated street-based IDUs. This compared to a national coverage of about 13%. Intervention cities had higher baseline HIV prevalence, reflecting their choice as intervention sites. More IDUs from intervention cities (59% vs. 27%) reported always using a clean syringe. Condom use with last sexual partner (24% vs. 11%) and HIV prevention knowledge were also higher amongst this group (all at p < 0.001). HIV prevalence in intervention cities remained unchanged in Faisalabad (13%) and Quetta (10%) but increased in Karachi (26-30%) and Lahore (4-7%). Coverage of sterile syringes for intervention cities was 30% compared to 13% nationwide. However within city, coverage varied from 30 to 99%. The costs of services varied widely by NGOs from USD 146 to 403.

Conclusions

IDUs interventions are performing well in some Pakistani cities. However, considerable expansion is needed to increase nationwide coverage.     

Injection behaviors among injection drug users in treatment: the role of hepatitis C awareness

Background

Injection drug use (IDU) is a primary vector for blood-borne infections. Awareness of Hepatitis C virus (HCV) infection status may affect risky injection behaviors. This study determines the prevalence of risky injection practices and examines associations between awareness of positive HCV status and risky injection behaviors.

Methods

We surveyed individuals seeking treatment for substance use at 12 community treatment programs as part of a national HIV screening trial conducted within the National Drug Abuse Treatment Clinical Trials Network. Participants reported socio-demographic characteristics, substance use, risk behaviors, and HCV status. We used multivariable logistic regression to test associations between participant characteristics and syringe/needle sharing.

Results

The 1281 participants included 244 (19.0%) individuals who reported injecting drugs in the past 6 months and 37.7% of IDUs reported being HCV positive. During the six months preceding baseline assessment, the majority of IDUs reported obtaining sterile syringes from pharmacies (51.6%) or syringe exchange programs (25.0%), but fewer than half of IDUs always used a sterile syringe (46.9%). More than one-third (38.5%) shared syringe/needles with another injector in the past 6 months. Awareness of positive HCV vs. negative/unknown status was associated with increased recent syringe/needle sharing (aOR 2.37, 95% CI 1.15, 4.88) in multivariable analysis.

Conclusions

Risky injection behaviors remain prevalent and awareness of HCV infection was associated with increased risky injection behaviors. New approaches are needed to broadly implement HCV prevention interventions for IDUs seeking addiction treatment.     

Modelling the prevalence of HCV amongst people who inject drugs: An investigation into the risks associated with injecting paraphernalia sharing

Background

In order to prevent the spread of the hepatitis C virus (HCV) amongst people who inject drugs (PWID), it is imperative that any injecting risk behaviour which may contribute to the transmission of disease has its role quantified. To inform public health organisations, mathematical modelling techniques were used to explore the risk of HCV infection through the sharing of injecting paraphernalia (including filters, cookers and water).

Methods

A mathematical model was developed for the spread of HCV based on the injecting behaviour of PWID in Scotland, with transmission occurring through the sharing of needles/syringes and other injecting paraphernalia. Numerical simulations were used to estimate the transmission probability for HCV through the sharing of injecting paraphernalia such that the modelled endemic HCV prevalence fitted with that observed amongst PWID in Scotland.

Results

The transmission probability of HCV through injecting paraphernalia was modelled to be over 8 times lower than that through needles/syringes (approximately 0.19–0.30% and 2.5%, respectively), assuming transmission occurs through a combination of at least filters and cookers. In the context of reported needle/syringe and paraphernalia sharing rates in Scotland, it is estimated that 38% and 62% of HCV infections are contributed by these practices, respectively. If needle/syringe sharing rates were to be twice those reported, the contributions would be 70% and 30%, respectively.

Conclusion

Given that the sharing of injecting paraphernalia among PWID is common, HCV transmission through this route could be contributing to the growing healthcare burden associated with this chronic disease. Every effort should therefore be made to establish (a) the contribution that paraphernalia sharing is making to the spread of HCV, and (b) the effectiveness of services providing sterile paraphernalia in preventing infection.     

The relationship between social network factors, HIV, and Hepatitis C among injection drug users in Chennai, India

Objective

The purpose of this study was to examine whether social network factors predict HIV and Hepatitis C (HCV) serostatus after controlling for individual-level factors at baseline among a cohort of male injection drug users in Chennai, India.

Methods

The sample, which was recruited through street outreach, consists of 1078 males who reported having injected drugs in the last 6 months.

Results

The participants reported 3936 social support and risk network members. HIV and HCV positive serostatus were negatively associated with network member providing emotional support, and positively associated with network member providing material support. In addition, HCV positivity was associated with network member being an active drug user known for more than 10 years and network member being male kin networks, even after adjusting for individual demographic factors and risk behaviors.

Conclusions

These findings suggest that social network factors are significantly linked to HIV and HCV status among IDUs in Southern India and highlight the mixed effects of social capital on health. Future HIV/HCV prevention efforts should incorporate IDU peers to alter drug network injection risk norms. For drug users who have minimal network support, support groups and other informal and formal support mechanisms may be need to help them with health care and psychological support needs for dealing with HIV/HCV.     

Gender differences in hepatitis C antibody prevalence and risk behaviours amongst people who inject drugs in Australia 1998–2008

BackgroundGlobal prevalence of hepatitis C virus (HCV) is estimated to be around 3% with approximately 170 million people affected. In Australia, and in many other resource rich countries, injecting drug use is the single most important risk factor for acquiring HCV, with around a third of diagnoses occurring in women. This study aims to assess gender differences in hepatitis C antibody prevalence and associated risk behaviours amongst a large sample of PWID in Australia.MethodsDuring a one to two week period in October, PWID attending selected NSP sites are invited to participate in the Australian NSP Survey. Between 1998 and 2008, approximately 16,000 individuals completed a self-administered questionnaire and provided a capillary blood sample for HIV and HCV antibody testing. We stratified our sample by time since onset of injecting and analysed the demographic characteristics, injecting behaviours and antibody test results to determine gender differences.ResultsWomen were found to be at increased risk of exposure to hepatitis C in all duration of injection categories except those injecting for 17 or more years. In the early years of injecting, women also reported higher rates of receptive sharing of needles and syringe and ancillary equipment when compared to men. Last injecting heroin, methadone or buprenorphine was significantly associated with HCV antibody prevalence amongst both males and females injecting for less than 5 years.ConclusionFindings indicate that women are at greater risk than men of HCV infection during the early years of injection through higher rates of receptive sharing of needles and syringes and/or ancillary equipment. Our results suggest that women who are new to injecting, and Indigenous women in particular, should be identified as priority populations when developing and implementing harm reduction strategies that target people who inject illicit drugs.     

Can intranasal drug use reduce HCV infection among injecting drug users?

Background

Preventing HCV infection among people who inject drugs is a difficult public health challenge. We examined the potential role of intranasal drug use in reducing HCV acquisition.

Methods

Subjects were recruited from IDUs entering the Beth Israel drug detoxification program from 2005 to 2010. A structured interview was administered and serum samples were collected for HCV testing.

Results

726 active injecting drug users were recruited from 2005 to 2010. HCV prevalence was 71%, 90% reported recent heroin injection and 44% reported recent intranasal heroin use. In a multiple logistic regression analysis, being HCV seropositive was associated with more years injecting, Latino ethnicity, previous testing for HCV, and recent injection of speedball, and negatively associated with recent intranasal use of heroin (AOR = 0.52, 95% CI 0.33-0.82) and intranasal use of speedball (AOR = 0.41, 95% CI 0.31-0.80). The association between intranasal heroin use and lower HCV seroprevalance was observed among both new injectors and persons with long injecting histories (16+ years since first injection).

Conclusion

Encouraging intranasal use as an alternative to injection among persons currently injecting drugs may be a viable strategy for reducing HCV transmission.     

Drug use and risk behaviour profile,and the prevalence of HIV,hepatitis C and hepatitis B among people with methamphetamine use in Iran

BackgroundStimulants substances use, particularly methamphetamine use, is increasing globally, including in Iran. This study assessed the drug use and risk behaviour profile, and prevalence of HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV) among a large population using methamphetamine as their primary drug in Iran.MethodsThis cross-sectional study was conducted in eight provinces of Iran. Individuals using methamphetamine for ≥3 months during the past three years, with no life-time history of injecting opioid drugs were enrolled. Drug use and risk behaviour data were collected through interviews. Blood samples were tested for HIV antibodies (HIV Ab), HCV antibodies (HCV Ab), and HBV surface antigen (HBs Ag).ResultAmong 567 participated, 84% were men and mean age was 36 years. Smoking with pipe was the most common method of methamphetamine use (53%), while 13% had a history of injecting methamphetamine, among whom 30% shared needles or syringes. Among those having sex during intoxication phase (n = 270), 48% never used condom. The prevalence of HIV Ab, HCV Ab and HBs Ag was 6.7% (95%CI: 4.7–9.1), 19.4% (95%CI: 16.2–22.9) and 1.4% (95%CI: 0.6–2.7), respectively. Age ≥ 30 years (adjusted OR [aOR]: 2.10, 95%CI: 1.18–3.76), lower education (high school vs. tertiary education, aOR: 13.95, 95%CI: 1.90–102.60), and injecting methamphetamine (aOR: 1.92, 95%CI 1.10–3.35) were significantly associated with HCV exposure. No factor was found associated with HIV infection. Among those reporting no potential injecting or sexual risk factors, 19.8% and 6.8% have HCV Ab positive and HIV Ab positive, respectively.ConclusionHigh prevalence of injecting and sexual risk behaviours, HIV infection and HCV exposure were found among individuals using methamphetamine as their primary drug, demonstrating them as an emerging population at risk of HIV and HCV in Iran. Targeted screening and harm reduction programs for this population are required.     

Moderate/heavy alcohol use and HCV infection among injection drug users in two Russian cities

Background

In Russia, injection drug use and transmission of blood-borne pathogens such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV) are inextricably linked, however the burden of alcohol use remains unexplored among injection drug users (IDUs).

Methods

Individuals who were 18 years of age and older and had injected drugs in the previous 30 days were recruited in the cities of Novosibirsk and Ivanovo by respondent driven sampling. Consenting individuals were administered a quantitative survey instrument and provided blood samples for serological testing.

Results

In Novosibirsk and Ivanovo, 29% and 35% of respondents were categorized as moderate/heavy drinkers, respectively. Individuals reported problems related to alcohol use that affected their physical health (23%), family (55%), and induced financial hardships (43%). In the multivariate analysis, we found that methamphetamine injection in the past 12 months was a strong and significant correlate of moderate/heavy drinking in Novosibirsk (aOR = 5.63 95% CI: [1.01–31.47]) and Ivanovo (aOR = 3.81 95% CI: [2.20–6.62]). There was poor agreement between self-reported HCV status and HCV test results (κ = −0.05 and 0.26 in Novosibirsk and Ivanovo, respectively). IDUs who correctly knew their HCV seropositive status in Novosibirsk and IDUs who correctly knew their HCV seronegative status in Ivanovo were significantly more likely to be moderate/heavy drinkers.

Conclusion

Alcohol use is problematic among IDUs who are at high risk for HCV. Future interventions should target IDUs who are moderate/heavy drinkers in order to prevent liver complications resulting from HCV infection.     

HIV/hepatitis coinfection in eastern Europe and new pan-European approaches to hepatitis prevention and management

ISSUES: HIV/hepatitis coinfection in Europe; WHO European clinical protocols on the management of people coinfected with HIV/AIDS and hepatitis B or C (HBV or HCV); stakeholder recommendations for better HCV services. INTRODUCTION: The increasing availability of highly active antiretroviral therapy throughout Europe and central Asia has changed comorbidity and mortality patterns among people living with HIV/AIDS (PLWHA) as liver disease has increasingly replaced AIDS as the cause of death in PLWHA in western European countries. The average prevalence of HCV among PLWHA is 40 per cent, and much higher in countries where the HIV epidemic is driven by injecting drug use. Access to hepatitis treatment for PLWHA and IDUs is still very limited in Europe due to a lack of clear clinical management guidelines for HIV/hepatitis coinfections, high costs and a national failure to recognise hepatitis as a critical health issue. DESCRIPTION: In October 2006, the WHO Regional Office for Europe issued protocols for the clinical management of HIV/HCV and HIV/HBV coinfections. They include diagnostic algorithms adjusted for resource availability, and guidelines for the management of patients who do not yet need treatment, those who need only hepatitis or only HIV/AIDS treatment, and those who need both. Though the protocols should provide practical guidelines for physicians and assist in the development of national treatment standards, there is still a need for targeted prevention, treatment and care interventions. To expand access to hepatitis prevention and treatment, public awareness needs to be raised and national political leaders need to address hepatitis as a public health issue. Effective public health measures include price reductions for anti-hepatitis drugs; targeted testing, counselling and prevention activities; increased access to hepatitis B and C treatment and to HBV vaccination for the populations most at risk.     

Human rights abuses and suicidal ideation among male injecting drug users in Delhi, India

Background

Human rights abuses, denial of care, police surveillance, and violence directed at IDUs have been found to impact HIV prevention efforts due to decreased attendance in harm reduction programs. The association of mental health status with rights abuses has not been examined extensively among drug users. In India, drug control laws are often in conflict with harm reduction policies, thus increasing the likelihood of rights abuses against IDUs. The purpose of this study was to describe human rights abuses occurring among IDUs in Delhi and examine their association with suicidal ideation.

Methods

343 IDUs were recruited in two research sites in Delhi through respondent driven sampling and were interviewed with a cross sectional survey questionnaire that included items on human rights and socio demographics.

Results

IDUs in the study experienced many human rights abuses. Notably among these were denial of admission into hospital (38.5%), denial of needles and syringes (20%), police arrests for carrying needles and using drugs (85%), verbal abuse (95%) and physical abuse (88%). Several human rights abuses were associated with suicidal ideation. These include being denied needles and syringes (OR: 7.28, 95% CI: 3.03-17.49); being arrested by police for carrying needles and using drugs (OR: 2.53, 95% CI: 1.06-6.03), and being physically abused (OR: 1.66, 95% CI: 1.05-2.23). The likelihood of suicidal ideation is also strongly related to the cumulative number of abuses.

Conclusions

These findings demonstrate that there is a high prevalence of human rights abuses among IDUs in Delhi. Given the alarming rate of suicidal ideation and its close relationship with human rights abuses it is essential that IDU interventions are executed within a rights-based framework.     

Prevalence of HIV/HCV/HBV infections and drug-related risk behaviours amongst IDUs recruited through peer-driven sampling in Iran

BackgroundThe control of blood-borne infections including HIV and hepatitis C (HCV) amongst injecting drug users (IDUs) is a challenge for health authorities in Iran. Hence, more reliable estimates of the levels of blood-borne infections and their associated factors are critically needed.MethodsActive IDUs were recruited using peer-driven sampling in a bio-behavioural survey in 2008. Over 8 weeks, data were collected from adults living in a city in Isfahan Province who had injected drugs in the past month. Participants provided a whole blood sample and answered questions on sexual and drug-related risk characteristics. Participants were provided post-test counselling and a non-monetary incentive for their participation. Excluding two inactive cases, the initial recruits resulted in 2–8 waves of recruitment.ResultsOverall, 118 IDUs including three females participated. The estimated population proportions of HIV, hepatitis B, and HCV infections were 0.7% (95% CI, 0.6–2.3), 0.7% (95% CI, 0.1–2.1), and 59.4% (95% CI, 47.4–68.7), respectively. Responses indicated that 31% (95% CI, 20–44.5) of the IDUs ever shared a needle/syringe for drug injection, and 77% (95% CI, 65–84) had ever injected an addictive solution marketed widely as Temgesic. Multivariate analyses revealed that the high prevalence of HCV infection amongst IDUs is associated with the lifetime duration of drug injection (AOR, 1.17; 95% CI, 1.01–1.34) and with having injected Temgesic (AOR, 4.73; 95% CI, 1.52–14.69).ConclusionOur experience in Iran indicates that IDUs can be recruited effectively in a bio-behavioural survey through peer-driven sampling and using only a single primary incentive. The high prevalence of HCV associated with injecting Temgesic is important evidence for harm-reduction policies in Iran.     

High dead-space syringes and the risk of HIV and HCV infection among injecting drug users

This study examines the association between using and sharing high dead-space syringes (HDSSs)—which retain over 1000 times more blood after rinsing than low dead-space syringes (LDSSs)—and prevalent HIV and hepatitis C virus (HCV) infections among injecting drug users (IDUs). A sample of 851 out-of-treatment IDUs was recruited in Raleigh–Durham, North Carolina, between 2003 and 2005. Participants were tested for HIV and HCV antibodies. Demographic, drug use, and injection practice data were collected via interviews. Data were analyzed using multiple logistic regression analysis. Participants had a mean age of 40 years and 74% are male, 63% are African American, 29% are non-Hispanic white, and 8% are of other race/ethnicity. Overall, 42% of participants had ever used an HDSS and 12% had shared one. HIV prevalence was 5% among IDUs who had never used an HDSS compared with 16% among IDUs who had shared one. The HIV model used a propensity score approach to adjust for differences between IDUs who had used an HDSS and those who had never used one. The HCV models included all potential confounders as covariates. A history of sharing HDSSs was associated with prevalent HIV (odds ratio = 2.50; 95% confidence interval = 1.01, 6.15). Use and sharing of HDSSs were also associated with increased odds of HCV infection. Prospective studies are needed to determine if sharing HDSSs is associated with increased HIV and HCV incidence among IDUs.     

HIV transmission from drug injectors to partners who do not inject,and beyond: Modelling the potential for a generalized heterosexual epidemic in St. Petersburg,Russia

Background

HIV infection is prevalent among drug injectors in St. Petersburg and their non-injecting heterosexual partners (PIDUs). There are fears that sexual transmission of HIV from IDUs to PIDUs may portend a self-sustaining, heterosexual epidemic in Russia.

Methods

Our model combines a network model of sexual partnerships of IDUs and non-IDUs to represent sexual transmission of HIV and a deterministic model for parenteral transmission among IDUs. Behavioural parameters were obtained from a survey of St. Petersburg IDUs and their sexual partners. We based our model fits on two scenarios for PIDU prevalence in 2006 (5.6% and 15.1%, calculated excluding and including HCV co-infected PIDUs respectively) and compared predictions for the general population HIV prevalence.

Results

Results indicate that sexual transmission could sustain a non-IDU HIV epidemic. The model indicates that general population prevalence may be greater than current estimates imply. Parenteral transmission drives the epidemic and the PIDU bridge population plays a crucial role transferring infection to non-IDUs. The model indicates that the high PIDU prevalence is improbable because of the high risk behaviour this implies; the lower prevalence is possible.

Conclusion

The model implies that transmission through PIDUs will sustain a heterosexual epidemic, if prevalence among IDUs and PIDUs is as high as survey data suggest. We postulate that current estimates of population prevalence underestimate the extent of the HIV epidemic because they are based on the number of registered cases only. Curtailing transmission among injectors and PIDUs will be vital in controlling heterosexual transmission.     

High prevalence but low awareness of hepatitis C virus infection among heroin users who received methadone maintenance therapy in Taiwan

Background

This study investigates the prevalence and correlates of hepatitis C virus (HCV) infections among heroin dependent individuals who received methadone maintenance therapy in Taiwan. Also, we investigate users' awareness of HCV.

Methods

Participants were 773 heroin users entering the methadone maintenance treatment (MMT) program at Tsaotun Psychiatric Center in Taiwan. The presence of HCV antibodies was detected. Multivariate logistic regression was used to identify the relationship between HCV infection and correlates.

Results

The prevalence of HCV infection was 90.8%. All participants who were HIV-positive were also infected with HCV. Multivariate logistic regression analysis showed that the route of heroin administration (injection), HIV-infection, and criminal records were significantly related to HCV infection. Few (34.8%) HCV positive heroin users were aware of their infection.

Conclusion

An extremely high prevalence of HCV infection but low awareness of their infection status was found among MMT patients in Taiwan. These findings highlight the importance of education regarding risky behaviors and the necessity for HCV treatment for this population in Taiwan.