People Who Inject Drugs Population Research Articles

Empirical evidence of recruitment bias in a network study of people who inject drugs

ABSTRACTBackground: Epidemiologic surveys of people who inject drugs (PWID) can be difficult to conduct because potential participants may fear exposure or legal repercussions. Respondent-driven sampling (RDS) is a procedure in which subjects recruit their eligible social contacts. The statistical validity of RDS surveys of PWID and other risk groups depends on subjects recruiting at random from among their network contacts.Objectives: We sought to develop and apply a rigorous definition and statistical tests for uniform network recruitment in an RDS survey.Methods: We undertook a detailed study of recruitment bias in a unique RDS study of PWID in Hartford, CT, the USA in which the network, individual-level covariates, and social link attributes were recorded. A total of participants (402 male, 123 female, and two individuals who did not specify their gender) within a network of 2626 PWID were recruited.Results: We found strong evidence of recruitment bias with respect to age, homelessness, and social relationship characteristics. In the discrete model, the estimated hazard ratios regarding the significant features of recruitment time and choice of recruitee were: alter’s age 1.03 [1.02, 1.05], alter’s crack-using status 0.70 [0.50, 1.00], homelessness difference 0.61 [0.43, 0.87], and sharing activities in drug preparation 2.82 [1.39, 5.72]. Under both the discrete and continuous-time recruitment regression models, we reject the null hypothesis of uniform recruitment.Conclusions: The results provide the evidence that for this study population of PWID, recruitment bias may significantly alter the sample composition, making results of RDS surveys less reliable. More broadly, RDS studies that fail to collect comprehensive network data may not be able to detect biased recruitment when it occurs.

Increasing importance of European lineages in seeding the hepatitis C virus subtype 1a epidemic in Spain.

BackgroundReducing the burden of the hepatitis C virus (HCV) requires large-scale deployment of intervention programmes, which can be informed by the dynamic pattern of HCV spread. In Spain, ongoing transmission of HCV is mostly fuelled by people who inject drugs (PWID) infected with subtype 1a (HCV1a).AimOur aim was to map how infections spread within and between populations, which could help formulate more effective intervention programmes to halt the HCV1a epidemic in Spain.MethodsEpidemiological links between HCV1a viruses from a convenience sample of 283 patients in Spain, mostly PWID, collected between 2014 and 2016, and 1,317, 1,291 and 1,009 samples collected abroad between 1989 and 2016 were reconstructed using sequences covering the NS3, NS5A and NS5B genes. To efficiently do so, fast maximum likelihood-based tree estimation was coupled to a flexible Bayesian discrete phylogeographic inference method.ResultsThe transmission network structure of the Spanish HCV1a epidemic was shaped by continuous seeding of HCV1a into Spain, almost exclusively from North America and European countries. The latter became increasingly relevant and have dominated in recent times. Export from Spain to other countries in Europe was also strongly supported, although Spain was a net sink for European HCV1a lineages. Spatial reconstructions showed that the epidemic in Spain is diffuse, without large, dominant within-country networks.ConclusionTo boost the effectiveness of local intervention efforts, concerted supra-national strategies to control HCV1a transmission are needed, with a strong focus on the most important drivers of ongoing transmission, i.e. PWID and other high-risk populations.

Geo-spatial analysis of individual-level needle and syringe coverage in Melbourne, Australia.

Distance to health services is known to be negatively associated with usage and needle and syringe programs (NSPs) for people who inject drugs (PWID) are no different. Australia has a mixture of NSP modalities (primary or secondary fixed-site NSPs), which may present unique barriers to access. In this study, we explore 1) the effect of distance to NSPs on individual-level needle and syringe coverage, and 2) differences in coverage dependent on NSP modality. Using data from 219 PWID in an ongoing cohort study in Melbourne, Australia, we measured the straight-line distance from participants’ residence to their nearest primary or secondary fixed-site NSP. We analysed the relationship between geographical distance and coverage via regression analysis. The median distance to any type of NSP was 1872 metres. Regardless of service type, 52% of participants lived within 2 kms of a fixed-site NSP and 87% lived within 5 kms. We found no association between distance to NSPs and syringe coverage or a significant difference in coverage by nearest service type. Our findings suggest that the number and distribution of NSPs in Melbourne, Australia caters adequately for the population of PWID.

Commentary on Grebely et al. (2019): Ending HCV epidemics among people who inject drugs.

The new direct-acting antiretroviral drugs for treating hepatitis C have generated considerable momentum for treating HCV infection among people who inject drugs and perhaps ‘ending the HCV epidemic’. There are, however, important epidemiological and behavior research problems that need to be addressed before ‘ending the HCV epidemic’ will be possible. The development of direct-acting antivirals (DAAs) that cure HCV infection in more than 90% of patients with minimal side effects has led to calls for ‘eliminating HCV infection’ or ‘ending HCV epidemics’ among people who inject drugs (PWID) 1. Some of the calls for eliminating HCV infection have included substantial allocations of new funds, e.g. New York State 2. Grebely et al. 3 have estimated the number and prevalence of people with a recent history (within past year) of injecting drug use who are living with hepatitis C virus (HCV) viremia and the proportion of people with recent injecting drug use among all people living with HCV infection at the global, regional and national levels. A major value of this study is its potential contribution as a baseline for ‘eliminating HCV’. While DAAs and the lessons from successfully controlling HIV among PWID in many areas 4 should certainly be useful in controlling HCV among PWID, the data presented in Grebely et al. illustrate that there is still a major amount of epidemiological and behavioral science that will be needed before ‘eliminating’ (or even ‘controlling’) HCV among PWID can be accomplished. First, what would ‘elimination/ending the epidemic’ of HCV among PWID look like? From early in the HIV epidemic among PWID, we had multiple examples, e.g. Glasgow, Scotland, Lund, Sweden, Sydney, Australia and Tacoma, WA, USA, where large-scale implementation of syringe access programs have kept HIV prevalence stable at less than 5% 5. The Grebely et al. data do not provide many (if any) examples of areas where HCV viremia has been stabilized at ‘ending the epidemic’ levels. Would 5% viremia in the local PWID population be a realistic goal? What sort of HCV combined prevention and care programs would be needed to stabilize HCV at 5% or less in a PWID population? Such a system would need to detect and treat existing cases of HCV infection as rapidly as new infections were occurring. Secondly, how will we develop better estimates of the size of PWID populations and the percentage of PWID who are HCV viremic? The uncertainty intervals in the Grebely et al. estimates are rather large, typically almost as large as the estimates themselves. Uncertainty in the estimates of the PWID population size and the percentage of PWID who are HCV viremic would create difficult problems for local officials who would have the task of allocating resources and planning logistical operations for rapidly scaling-up treatment for HCV-infected PWID. Thirdly, what new interventions can be developed to reduce HCV transmission behavior among viremic PWID? One of the important factors in HIV prevention was that PWID who learned that they were HIV-seropositive greatly reduced transmission behavior (passing their used needles and syringes to others) well before antiretroviral therapy (ART) was available 6. We have not yet seen the equivalent reductions in transmission behaviors among PWID who know that they are HCV-seropositive 7. How do we successfully encourage HCV viremic PWID to reduce transmission behavior? Fourthly, what interventions can be developed and implemented to reduce the very high HCV incidence rates among people who have recently begun injecting drugs 8? Many new injectors typically do not identify as ‘drug injectors’, and thus do not utilize HIV/HCV safer injection programs 9. Fifthly, what interventions will be implemented to reduce the rates that drug users transition to injecting drug use? There have been calls for more research on this topic 10, and there are current research studies addressing this subject. However, the objective should be to develop an evidence base for reducing initiation into injecting drug use that is comparable to the evidence base for medication assisted treatment and for syringe access programs. The new DAAs certainly give us the capability of treating very large numbers of HCV infected people who use drugs and greatly reduce morbidity and mortality, and programs to provide access to HCV treatment should be scaled-up in high-, middle- and low-income countries as quickly as feasible, and the additional research needed to learn how to ‘end HCV epidemics’ among PWID should be funded. Finally, and perhaps most importantly, while the above may be considered scientific tasks, it is important to emphasize that the research should be conducted in full collaboration with PWID and drug-user organizations. Such collaboration should not only greatly improve the quality of the research, but also greatly improve the likelihood that the findings will be incorporated into public health programs that could ‘end the HCV epidemic’ among people who use drugs. None.

Prevalence of hepatitis C virus in young people who inject drugs in four Colombian cities: A cross-sectional study using Respondent Driven Sampling

BackgroundColombia has a growing population of young people who inject drugs (PWID). Despite the previously reported association of injection drug use with hepatitis c virus (HCV) in other countries, studies on HCV prevalence in PWID in Colombia are lacking. The objective of this study is to determine the prevalence, demographics, and correlations of risky injection behaviours in HCV seropositive PWID in four Colombian cities (Armenia, Bogotá, Cúcuta and Pereira). MethodsThis was a cross-sectional study carried out between January and June of 2014 that included 918 PWID from four Colombian cities, recruited by Respondent Driven Sampling. A survey was administered to each participant, and blood samples were collected. Binary logistic regression and multivariate analyses for each city were conducted. ResultsAverage participant age was 26 years (SD 6.5). Of all participants, 27.3% of PWID were HCV seropositive, of which 52% were 25 years old or younger. In Pereira, increased risk of HCV infection was found for PWID that: had a history of injection drug use of 5 years or more (AOR: 3.0, CI: 1.7–7.8); were between 25 and 28 years of age (AOR: 5.2, CI: 1.0–26.3); had higher injection frequency (AOR: 2.5, CI: 1.4–4.2), and daily use of gifted, sold, or rented needles or syringes (AOR: 4.5, CI: 1.0–7.1). Additionally, in Cucuta, being HIV seropositive appeared to be greatly associated with risk of HCV seropositivity (AOR: 16.9, CI: 3.5–81.5). ConclusionAlthough prevalence of HCV in PWID in Colombia is lower than that reported for other countries, the described demographic characteristics and diverse risky injection behaviors on each city, in the context of a young PWID population with a short injection drug use history, should be taken into account in order to guide efforts towards preventing and reducing risk of HCV infection in PWID in Colombia.

Incidence and spontaneous clearance of hepatitis C virus (HCV) in people who inject drugs at the Stockholm Needle Exchange-Importance for HCV elimination.

The major transmission route for hepatitis C virus (HCV) is through sharing of unsterile injection equipment among people who inject drugs (PWID). The WHO strategy for HCV elimination by 2030 proposes increased efforts to treat PWID populations that drive the HCV epidemic. Among participants in the Stockholm needle exchange programme (NEP), the HCV prevalence is 60%. We aimed to study HCV incidence, spontaneous HCV clearance rate, and predictors associated with new HCV infections and reinfections in NEP participants. All 2320 patients enrolled in the programme between 8 April 2013 and 23 September 2016 were tested for HCV at baseline, and responded to a questionnaire regarding sociodemographic data and injection risk behaviour. Tests for HCV were repeated at an interval of 3-6months. The anti-HCV prevalence in the NEP participants at baseline was 77%, and the prevalence of HCV RNA was 57%. 24% of the anti-HCV positive were HCV RNA negative with a spontaneously cleared HCV infection. The overall HCV incidence rate was 22/100 PY. The HCV incidence rate in the HCV naive group was 26/100 PY, and in the spontaneously cleared group 19/100. Although there were no significant differences in becoming HCV infected between the two groups (31% vs 29%), the rate of spontaneous HCV clearance was significantly lower in the HCV naive group, 20% vs 44%, (P<0.05). A high HCV incidence rate was noted among the PWID indicating that treatment needs to be scaled up in conjunction with harm reduction measures to achieve HCV elimination goals set by WHO. This includes high coverage needle exchange programmes and effective addiction treatment for substance users, including opiate substitution treatment.

A Bayesian approach to synthesize estimates of the size of hidden populations: the Anchored Multiplier.

The multiplier method is one of the most frequently used population size estimation (PSE) methods for key populations, yet estimates from this method are often inconsistent with each other, other PSE methods and local knowledge. We developed a novel Bayesian approach, the 'Anchored Multiplier', which synthesizes estimates from multipliers coupled to an a priori estimate to arrive at a single consensus estimate and credible range. Data for size estimation were collected from three cross-sectional bio-behavioural surveillance studies of people who inject drugs (PWID) in San Francisco, CA, USA (2005, 2009 and 2012). We demonstrate the application of the Anchored Multiplier and a Variance Adjusted-Anchored Multiplier using PSE produced by multipliers in the three surveys and the literature for the USA. Size estimates were compared with estimates from other available PSE methods. Using the Anchored Multiplier, we estimated the PWID population made up 2.41% [95% credible interval (CI): 1.9-2.85] of the adult population in 2005, 2.1% (95% CI: 1.8-2.48) in 2009 and 2.3% (95% CI: 2.03-2.61) in 2012. The Variance Adjusted-Anchored Multiplier calculated similar point estimates, with wider 95% credible intervals. Credible intervals from both approaches were substantially narrower than from other standard PSE methods and, unlike other methods, indicated that the prevalence of PWID was stable over time. The Anchored Multiplier is a promising new approach to size estimation, which generates a single estimate to inform programmatic strategies to counter the HIV epidemic, and provides a robust denominator to quantify the burden of disease for key populations.

Risk behaviours of NPS users in Hungary and the possibility of harm reduction

Introduction. In recent years, the use of injectable new psychoactive substances (NPS) has become a widespread phenomenon. Aim. The aim of this paper was to investigate NPS-related risk behaviours in the context of infectious diseases. Material and methods. Our survey was conducted as a part of a low threshold HCV, HIV, syphilis screening intervention which allowed to reach the people who inject drugs (PWID) population otherwise invisible for the healthcare system, and investigate their injecting and sexual risk behaviours. The survey was based on a risk assessment questionnaire which was a part of a quick screening and counselling intervention provided on site in four cities in Hungary. Results. Injecting NPS is a risk factor – NPSs are injected more frequently than amphetamines or heroin. The limited access to needle exchange programmes with the recent rise in HCV prevalence in the Hungarian PWID population combined with equipment sharing, could lead to a serious public health problem. Conclusions. Scaling up harm reduction interventions is essential to prevent further risks to the population.

Identifying injection drug use and estimating population size of people who inject drugs using healthcare administrative datasets

BackgroundLarge linked healthcare administrative datasets could be used to monitor programs providing prevention and treatment services to people who inject drugs (PWID). However, diagnostic codes in administrative datasets do not differentiate non-injection from injection drug use (IDU). We validated algorithms based on diagnostic codes and prescription records representing IDU in administrative datasets against interview-based IDU data. MethodsThe British Columbia Hepatitis Testers Cohort (BC-HTC) includes ∼1.7 million individuals tested for HCV/HIV or reported HBV/HCV/HIV/tuberculosis cases in BC from 1990 to 2015, linked to administrative datasets including physician visit, hospitalization and prescription drug records. IDU, assessed through interviews as part of enhanced surveillance at the time of HIV or HCV/HBV diagnosis from a subset of cases included in the BC-HTC (n = 6559), was used as the gold standard. ICD-9/ICD-10 codes for IDU and injecting-related infections (IRI) were grouped with records of opioid substitution therapy (OST) into multiple IDU algorithms in administrative datasets. We assessed the performance of IDU algorithms through calculation of sensitivity, specificity, positive predictive, and negative predictive values. ResultsSensitivity was highest (90–94%), and specificity was lowest (42–73%) for algorithms based either on IDU or IRI and drug misuse codes. Algorithms requiring both drug misuse and IRI had lower sensitivity (57–60%) and higher specificity (90–92%). An optimal sensitivity and specificity combination was found with two medical visits or a single hospitalization for injectable drugs with (83%/82%) and without OST (78%/83%), respectively. Based on algorithms that included two medical visits, a single hospitalization or OST records, there were 41,358 (1.2% of 11–65 years individuals in BC) recent PWID in BC based on health encounters during 3- year period (2013–2015). ConclusionAlgorithms for identifying PWID using diagnostic codes in linked administrative data could be used for tracking the progress of programing aimed at PWID. With population-based datasets, this tool can be used to inform much needed estimates of PWID population size.

Model projections on the impact of HCV treatment in the prevention of HCV transmission among people who inject drugs in Europe

Prevention of hepatitis C virus (HCV) transmission among people who inject drugs (PWID) is critical for eliminating HCV in Europe. We estimated the impact of current and scaled-up HCV treatment with and without scaling up opioid substitution therapy (OST) and needle and syringe programmes (NSPs) across Europe over the next 10 years. We collected data on PWID HCV treatment rates, PWID prevalence, HCV prevalence, OST, and NSP coverage from 11 European settings. We parameterised an HCV transmission model to setting-specific data that project chronic HCV prevalence and incidence among PWID. At baseline, chronic HCV prevalence varied from <25% (Slovenia/Czech Republic) to >55% (Finland/Sweden), and <2% (Amsterdam/Hamburg/Norway/Denmark/Sweden) to 5% (Slovenia/Czech Republic) of chronically infected PWID were treated annually. The current treatment rates using new direct-acting antivirals (DAAs) may achieve observable reductions in chronic prevalence (38-63%) in 10 years in Czech Republic, Slovenia, and Amsterdam. Doubling the HCV treatment rates will reduce prevalence in other sites (12-24%; Belgium/Denmark/Hamburg/Norway/Scotland), but is unlikely to reduce prevalence in Sweden and Finland. Scaling-up OST and NSP to 80% coverage with current treatment rates using DAAs could achieve observable reductions in HCV prevalence (18-79%) in all sites. Using DAAs, Slovenia and Amsterdam are projected to reduce incidence to 2 per 100 person years or less in 10 years. Moderate to substantial increases in the current treatment rates are required to achieve the same impact elsewhere, from 1.4 to 3 times (Czech Republic and France), 5-17 times (France, Scotland, Hamburg, Norway, Denmark, Belgium, and Sweden), to 200 times (Finland). Scaling-up OST and NSP coverage to 80% in all sites reduces treatment scale-up needed by 20-80%. The scale-up of HCV treatment and other interventions is needed in most settings to minimise HCV transmission among PWID in Europe. Measuring the amount of HCV in the population of PWID is uncertain. To reduce HCV infection to minimal levels in Europe will require scale-up of both HCV treatment and other interventions that reduce injecting risk (especially OST and provision of sterile injecting equipment).

Hepatitis C virus dynamics among intravenous drug users suggest that an annual treatment uptake above 10% would eliminate the disease by 2030.

In Switzerland, the prevalence of hepatitis C virus (HCV) among people who inject drugs (PWID) has been decreasing owing to active harm reduction efforts and an aging population. Recent advances in HCV therapeutics may provide an opportunity to direct treatment to high-risk populations, with a goal of reducing HCV prevalence and preventing new infections. In order to guide these efforts, the current project was undertaken with the following aims: (1) to develop a simple model to estimate the number of new HCV infections using available data on PWID; (2) to examine the impact of intervention strategies (prevention and treatment) on new and total HCV infections among PWID. A dynamic HCV transmission model was used to track HCV incidence and prevalence among active PWID according to their harm reduction status. The relative impact of treating 1, 5, 10 or 15% of HCV+ PWID with new oral direct acting antivirals was considered. In 2015, there were an estimated 10 160 active PWID in Switzerland, more than 85% of whom were engaged in harm reduction programmes. Approximately 42% of active PWID were HCV-RNA+, with 55 new viraemic infections occurring annually. By 2030, a 60% reduction in the HCV+ PWID population would be expected. In the absence of behavioural changes, the number of secondary infections would increase under all treatment scenarios. With high level treatment, the number of secondary infections would peak and then drop, corresponding to depletion of the viral pool. In Switzerland, 5% treatment of the 2015 HCV+ PWID population per year would result in a 95% reduction in total cases by 2030, whereas ≥10% treatment would result in a >99% reduction. Timely treatment of hepatitis C virus among people who inject drugs is necessary to reduce the prevalence and prevent new infections in Switzerland.

Epidemic dispersion of HIV and HCV in a population of co-infected Romanian injecting drug users.

Co-infections with HIV and HCV are very frequent among people who inject drugs (PWID). However, very few studies comparatively reconstructed the transmission patterns of both viruses in the same population. We have recruited 117 co-infected PWID during a recent HIV outbreak in Romania. Phylogenetic analyses were performed on HIV and HCV sequences in order to characterize and compare transmission dynamics of the two viruses. Three large HIV clusters (2 subtype F1 and one CRF14_BG) and thirteen smaller HCV transmission networks (genotypes 1a, 1b, 3a, 4a and 4d) were identified. Eighty (65%) patients were both in HIV and HCV transmission chains and 70 of those shared the same HIV and HCV cluster with at least one other patient. Molecular clock analysis indicated that all identified HIV clusters originated around 2006, while the origin of the different HCV clusters ranged between 1980 (genotype 1b) and 2011 (genotypes 3a and 4d). HCV infection preceded HIV infection in 80.3% of cases. Coincidental transmission of HIV and HCV was estimated to be rather low (19.65%) and associated with an outbreak among PWID during detention in the same penitentiary. This study has reconstructed and compared the dispersion of these two viruses in a PWID population.

Improving Cascade of Hepatitis C Care Through Linkage to C Care Program (LTC)

Introduction: The epidemic of injectable drug use accounts for at least 75% of new HCV infections in the United States; most of whom fail to seek treatment for this curable illness. The Center for Disease Control (CDC) recommends targeted HCV testing in the people who inject drugs (PWID) population. Therefore, increasing education, screening, and linkage to care by working through environments which cater to this audience such as methadone clinics, Sober Living Homes, and drug rehabilitation centers. One challenge in testing PWID is the inability of these individuals to follow through with linkage to careand treatment following a positive test. Our aim is to screen the PWID population and link individuals that are HCV RNA positive to care, and utilize our online patient database management system (PDMS) with our Substance Abuse Treatment Center partners to fulfill the linkage portion. Methods: Longitudinal prospective cohort study with HCV screening at the above centers and utilization of a HIPPA compliant online patient database management system (PDMS) (http://www.linkagetocare.com). A centrally located Linkage to Care Specialist (LTCS) is notified immediately when an individual is entered in the system by the treatment center or is self-referred. The LTCS educates the individual and proceeds to link that person to care. Results: January 2017 - May 2017, 289 HCV RNA positive patients referred (31% self-referred and 54% referred from 24 facilities in 15 states); 66% patients were uninsured; Median age of patients 41 (19-77); 58% males. 246 (85%) patients were contacted by LTCS; 173 (70%) HCV patients referred by the LTCS to a medical provider; patients were contacted within 2 days after referral. On average, patients were contacted twice before scheduling their first appointment. 120 (49%) patients made it to their first appointment and 30 (25%) of them initiated HCV treatment; 9 (30%) patients finished therapy. 70% of patients were from sober living; 71% seen in office vs. 14% through telemedicine. Conclusion: Targeting PWID is an effective way of reducing the prevalence of HCV infection and ultimately eliminating HCV in high risk communities. The LTC model results in an increase in patient compliance as compared to the failed cycle of current care models. The continued goal of this project will be to enhance HCV identification amongst at-risk populations, further education; providing a link to care for all patients affected by HCV.

Direct-acting antiviral agents for HCV infection affecting people who inject drugs.

Globally, 12 million people are estimated to have injected drugs in the past year, 50% of whom have chronic HCV infection, with people who have previously injected drugs presenting an additional large reservoir of infection. The availability of simple and tolerable interferon-free direct-acting antiviral agents (DAAs) for HCV infection, which have a cure rate of >95% represents one of the most exciting advances in clinical medicine in the past few decades. Adherence and response to DAA therapy among people who inject drugs (PWID) receiving opioid substitution therapy (OST) in clinical trials are comparable to populations without a history of injecting drugs. Further data are required among current PWID not receiving OST. Given the potential prevention benefits of treatment, DAAs have enhanced cost-effectiveness among PWID. As HCV therapy is expanded to populations of PWID with high-risk behaviours for re-exposure, acknowledgement that HCV reinfection will occur is crucial, and appropriate strategies must be in place to maximize prevention of reinfection and offer retreatment for reinfection. This Review will also discuss essential components for broadening access to HCV care for PWID as we strive for the global elimination of HCV infection.

Recovery of Infectious Hepatitis C Virus From Injection Paraphernalia: Implications for Prevention Programs Serving People Who Inject Drugs.

Controlling hepatitis C virus (HCV) transmission among people who inject drugs (PWID) has focused on preventing sharing syringes and drug preparation paraphernalia, but it is unclear whether HCV incidence linked to sharing paraphernalia reflects contamination of the paraphernalia or syringe-mediated contamination when drugs are shared. In experiments designed to replicate real-world injection practices when drugs are shared, the residual contents of HCV-contaminated syringes with detachable or fixed needled were passed through the "cookers" and filters used by PWID in preparing drugs for injection and then introduced into a second syringe. All items were tested for the presence of infectious HCV using a chimeric HCV with a luciferase gene. Hepatitis C virus could not be recovered from cookers regardless of input syringe type or cooker design. Recovery was higher when comparing detachable needles to fixed needles for residue in input syringes (73.8% vs 0%), filters (15.4% vs 1.4%), and receptive syringes (93.8% vs 45.7%). Our results, consistent with the hypothesis that sharing paraphernalia does not directly result in HCV transmission but is a surrogate for transmissions resulting from sharing drugs, have important implications for HCV prevention efforts and programs that provide education and safe injection supplies for PWID populations.

Using a programmatic mapping approach to plan for HIV prevention and harm reduction interventions for people who inject drugs in three South African cities

BackgroundStigma, criminalisation and a lack of data on drug use contribute to the “invisibility” of people who inject drugs (PWID) and make HIV prevention and treatment service delivery challenging. We aimed to confirm locations where PWID congregate in Cape Town, eThekwini and Tshwane (South Africa) and to estimate PWID population sizes within selected electoral wards in these areas to inform South Africa’s first multi-site HIV prevention project for PWID.MethodsField workers (including PWID peers) interviewed community informants to identify suspected injecting locations in selected electoral wards in each city and then visited these locations and interviewed PWID. Interviews were used to gather information about the accessibility of sterile injecting equipment, location coordinates and movement patterns. We used the Delphi method to obtain final population size estimates for the mapped wards based on estimates from wisdom of the crowd methods, the literature and programmatic data.ResultsBetween January and April 2015, we mapped 45 wards. Tshwane teams interviewed 39 PWID in 12 wards, resulting in an estimated number of accessible PWID ranging from 568 to 1431. In eThekwini, teams interviewed 40 PWID in 15 wards with an estimated number of accessible PWID ranging from 184 to 350. The Cape Town team interviewed 61 PWID in 18 wards with an estimated number of accessible PWID ranging between 398 and 503. Sterile needles were only available at one location. Almost all needles were bought from pharmacies. Between 80 and 86% of PWID frequented more than one location per day. PWID who reported movement visited a median of three locations a day.ConclusionsProgrammatic mapping led by PWID peers can be used effectively to identify and reach PWID and build relationships where access to HIV prevention commodities for PWID is limited. PWID reported limited access to sterile injecting equipment, highlighting an important HIV prevention need. Programmatic mapping data show that outreach programmes should be flexible and account for the mobile nature of PWID populations. The PWID population size estimates can be used to develop service delivery targets and as baseline measures.

Delivering direct acting antiviral therapy for hepatitis C to highly marginalised and current drug injecting populations in a targeted primary health care setting

BackgroundThe Kirketon Road Centre (KRC) is a community-based public health facility in Sydney, Australia, that provides healthcare to people who inject drugs (PWID), including hepatitis C virus (HCV) treatment. From March 2016, the Australian Government has provided access to direct-acting antivirals (DAA) for adults with chronic HCV, without liver disease stage or drug and alcohol use restrictions. The aim of this study was to report DAA treatment outcomes among highly marginalised PWID treated at KRC. MethodsAll individuals initiating DAA treatment at KRC and due for sustained virological response (SVR12) testing by end 2016 were included. Demographic, drug use behaviour, clinical parameters, adherence support and HCV treatment outcomes, including SVR12 were recorded. Factors associated with SVR12, loss-to-follow-up (LTFU) and delayed SVR12 testing (>SVR16) were assessed by multivariate analysis. SVR12 was assessed by intention-to-treat (ITT) and modified ITT, the latter excluding individuals with an end-of-treatment response (ETR) but no SVR12 assessment, or who postponed their SVR12 date due to treatment interruption. ResultsA total of 72 individuals commencing DAAs were included, of whom 67% were male, 30% homeless, and 32% Aboriginal. All had a lifetime history of injecting drug use, with 75% having injected within the last six months, and 44% injecting at least weekly; 25% were also enrolled in opioid substitution therapy. Twenty-five (35%) individuals elected to receive an enhanced adherence-support package. Fifty-nine of 72 (82%) individuals due for SVR12 attended for testing, of whom 59/59 (100%) achieved SVR, providing an ITT SVR of 82%. A further six individuals had undetectable HCV RNA at ETR, but no SVR12 assessment, and one interrupted treatment, providing a mITT SVR of 91%. Homelessness was associated with delayed SVR12 testing (OR 24.9 95%CI 2.9–212.8, p=0.003). There was no association between LTFU and frequency of drug injection, last drug injected, or planned treatment duration. ConclusionThis study confirms that PWID can be successfully treated for HCV in a real-world setting using an integrated primary health care model. It also demonstrates feasibility to upscale DAA therapy in high-risk PWID populations, with potential individual and population-level public health benefits. Enhanced efforts are required to optimise post-treatment follow-up.

Chronic hepatitis C and individuals with a history of injecting drugs in Spain: population assessment, challenges for successful treatment.

In Spain, there is a need to improve chronic hepatitis C care among people who inject drugs (PWID). Injecting drug use is an important risk behaviour for hepatitis C virus (HCV) infection. Review of 28 sources of the relevant published literature mapped the size of the addiction-HCV population in Spain. Experts in opioid use disorder (OUD) treatment in Spain completed a consensus to define the population size, HCV prevalence and access or barriers to hepatitis C treatment for PWID populations. In Spain, over 300 000 individuals have a lifetime history of injecting drugs. Currently, 150 000 individuals in Spain have OUD; many have injected drugs. Each year, 80 000 individuals engage with treatment services for OUD. A proportion of this group continues to inject drugs. There is a high HCV prevalence in PWID - estimates of 60-80% in Spain. Uptake of hepatitis C therapy in PWID in Spain is limited; barriers include awareness of treatment pathways, advocacy for regular screening and effective joint care. There is an urgent need to address barriers to effective hepatitis C care for PWID in Spain. Practical and specific strategies including peer-led solutions, patient buddy systems and joint working models at the local level can make important short-term differences.

Impact of opioid substitution therapy on the HIV prevention benefit of antiretroviral therapy for people who inject drugs.

A recent meta-analysis suggested that opioid substitution therapy (OST) increased uptake of antiretroviral treatment (ART) and HIV viral suppression. We modelled whether OST could improve the HIV prevention benefit achieved by ART among people who inject drugs (PWID). We modelled how introducing OST could improve the coverage of ART across a PWID population for different baseline ART coverage levels. Using existing data on how yearly HIV-transmission risk is related to HIV plasma viral load, changes in the level of viral suppression across the population were used to project the relative reduction in yearly HIV-transmission risk achieved by ART, with or without OST, compared with if there was no ART - defined here as the prevention effectiveness of ART. Owing to OST use increasing the chance of being on ART and achieving viral suppression if on ART, the prevention effectiveness of ART for PWID on OST (compared with PWID not on OST) increases by 44, 31, or 20% for a low (20%), moderate (40%), or high (60%) baseline ART coverage, respectively. Improvements in the population-level prevention effectiveness of ART are also achieved across all PWID, compared with if OST was not introduced. For instance, if OST is introduced at 40% coverage, the population-level prevention effectiveness of ART could increase by 27, 20, or 13% for a low (20%), moderate (40%), or high (60%) baseline ART coverage, respectively. OST could improve the HIV prevention benefit of ART; supporting strategies that aim to concurrently scale-up OST with ART.

Behavioral characteristics and injection practices associated with skin and soft tissue infections among people who inject drugs: A community-based observational study

ABSTRACTBackground: People who inject drugs (PWID) are at increased risk for bacterial skin and soft tissue infections (SSTIs). Although SSTIs pose significant health risks, little is known about their prevalence and characteristics in the population of PWID in the United States. This study investigates whether behavioral factors related to skin and equipment hygiene and tissue-damaging injection practices are associated with recent SSTIs among PWID. Methods: Active PWID were recruited using targeted sampling in San Francisco in 2011–2013. Interviewers collected information on behavioral risk factors of past-month self-reported SSTIs. Inferential analyses used multivariate logistic regression methods (i.e., generalized linear model) to characterize risk factors for past-month SSTIs. Results: The self-reported prevalence of lifetime, past-year, and past-month SSTI was 70%, 29%, and 11%, respectively. Several factors were significantly associated with past-month SSTIs in bivariate analysis, including injecting nonpowder drugs (odds ratio [OR] = 3.57; 95% confidence interval [CI] = 1.23, 10.35; P = .01), needle-licking before injection (OR = 3.36; 95% CI = 1.28, 8.81; P = .01), injecting with someone else's preused syringe/needle (OR = 7.97; 95% CI = 2.46, 25.83; P < .001), being injected by another person (OR = 2.63; 95% CI = 1.02, 6.78; P = .04), infrequent skin cleaning before injection (OR = 2.47; 95% CI = 1.00, 6.10; P = .04), and frequent injections (P = .02). In multivariate analysis, only syringe/needle sharing (adjusted OR = 6.38; 95% CI = 1.90, 21.46) remained statistically significant. Conclusion: SSTIs are common among PWID. These data highlight the importance of clinical and public health screening efforts to reduce SSTIs. Needle exchange programs may be good venues for SSTIs screening and treatment.