Incidence of hepatitis C in drug injectors: the role of homelessness, opiate substitution treatment, equipment sharing, and community size

Association of spatial proximity to fixed-site syringe services programs with HCV serostatus and injection equipment sharing practices among people who inject drugs in rural New England, United States

BACKGROUND

Hepatitis C virus (HCV) disproportionately affects rural communities, where health services are geographically dispersed. It remains unknown whether proximity to a syringe services program (SSP) is associated with HCV infection among rural people who inject drugs (PWID).

METHODS

Data are from a cross-sectional sample of adults who reported injecting drugs in the past 30 days recruited from rural counties in New Hampshire, Vermont, and Massachusetts (2018-2019). We calculated the road network distance between each participant's address and the nearest fixed-site SSP, categorized as ≤ 1 mile, 1-3 miles, 3-10 miles, and > 10 miles. Staff performed HCV antibody tests and a survey assessed past 30-day injection equipment sharing practices: borrowing used syringes, borrowing other used injection equipment, and backloading. Mixed effects modified Poisson regression estimated prevalence ratios (aPR) and 95% confidence intervals (95% CI). Analyses were also stratified by means of transportation.

RESULTS

Among 330 PWID, 25% lived ≤ 1 mile of the nearest SSP, 17% lived 1-3 miles of an SSP, 12% lived 3-10 miles of an SSP, and 46% lived > 10 miles from an SSP. In multivariable models, compared to PWID who lived within 1 mile of an SSP, those who lived 3 to 10 miles away had a higher prevalence of HCV seropositivity (aPR: 1.25, 95% CI 1.06-1.46), borrowing other used injection equipment (aPR: 1.23, 95% CI 1.04-1.46), and backloading (aPR: 1.48, 95% CI 1.17-1.88). Similar results were observed for PWID living > 10 miles from an SSP: aPR [HCV]: 1.19, 95% CI 1.01-1.40; aPR [borrowing other used equipment]:1.45, 95% CI 1.29-1.63; and aPR [backloading]: 1.59, 95% CI 1.13-2.24. Associations between living 1 to 3 miles of an SSP and each outcome did not reach statistical significance. When stratified by means of transportation, associations between distance to SSP and each outcome (except borrowing other used injection equipment) were only observed among PWID who traveled by other means (versus traveled by automobile).

CONCLUSIONS

Among PWID in rural New England, living farther from a fixed-site SSP was associated with a higher prevalence of HCV seropositivity, borrowing other used injection equipment, and backloading, reinforcing the need to increase SSP accessibility in rural areas. Means of transportation may modify this relationship.

Accessing hepatitis C direct acting antivirals among people living with hepatitis C: a qualitative study

BACKGROUND

Hepatitis C is curable with direct-acting antivirals (DAAs). However, treatment uptake remains low among marginalized populations such as people who inject drugs. We sought to understand challenges to treatment uptake with DAAs among people living with hepatitis C and compare treatment experiences between people who do and do not inject prescription and/or unregulated drugs.

METHODS

We conducted a qualitative study using focus groups with 23 adults aged 18 years and over who completed DAA treatment or were about to begin such treatment at the time of the study. Participants were recruited from hepatitis C treatment clinics across Toronto, Ontario. We drew upon stigma theory to interpret participants' accounts.

RESULTS

Following analysis and interpretation, we generated five theoretically-informed themes characterizing the experiences of individuals accessing DAAs: "being 'worthy' of the cure", "spatially enacted stigma", "countering social and structural vulnerability: the importance of peers", "identity disruption and contagion: attaining a 'social cure'" and "challenging stigma with population-based screening". Overall, our findings suggest that structural stigma generated and reproduced through healthcare encounters limits access to DAAs among people who inject drugs. Peer-based programs and population-based screening were proposed by participants as mechanisms for countering stigma within health care settings and 'normalizing' hepatitis C among the general population.

CONCLUSIONS

Despite the availability of curative therapies, access to such treatment for people who inject drugs is limited by stigma enacted in and structured within healthcare encounters. Developing novel, low-threshold delivery programs that remove power differentials and attend to the social and structural determinants of health and reinfection are needed to facilitate further scale up of DAAs and support the goal of eradicating hepatitis C as a public health threat.

Incidence of HIV and hepatitis C virus among people who inject drugs, and associations with age and sex or gender: a global systematic review and meta-analysis

BACKGROUND

Measuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender.

METHODS

In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle-Ottawa scale. This study is registered with PROSPERO, CRD42020220884.

FINDINGS

Our updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987-2021 for HIV and 1992-2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3-2·3; I2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0-14·6; I2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2-1·8; I2=66·9%) and HCV (1·5, 1·3-1·8; I2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1-1·6; I2=55·3%) and HCV (1·2, 1·1-1·3; I2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6-7), indicating moderate risk.

INTERPRETATION

Although sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs.

FUNDING

Canadian Institutes of Health Research, Fonds de recherche du Québec-Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO.

HCV serostatus and injection sharing practices among those who obtain syringes from pharmacies and directly and indirectly from syringe services programs in rural New England

BACKGROUND

Among people who inject drugs (PWID), obtaining syringes via syringe services programs (SSPs) and pharmacies reduces injection sharing practices associated with hepatitis C virus (HCV). Whether indirect use of SSPs via secondary exchange confers a similar benefit remains unknown, particularly in rural settings. We compared HCV serostatus and injection sharing practices by primary syringe source among a sample of rural PWID.

METHODS

Data are from a cross-sectional study of adults who use drugs recruited from eleven rural counties in New Hampshire, Vermont, and Massachusetts using respondent-driven sampling (2018-2019). Study staff performed HCV antibody testing. An audio computer-assisted self-interview assessed sociodemographic characteristics, past 30-day injection practices, and past 30-day primary syringe source. Primary syringe source was classified as direct SSP, pharmacy, indirect SSP (secondary exchange), or "other" (friend/acquaintance, street seller, partner/relative, found them). Mixed effects modified Poisson models assessed the association of primary syringe source with HCV seroprevalence and injection sharing practices.

RESULTS

Among 397 PWID, the most common primary syringe source was "other" (33%), then pharmacies (27%), SSPs (22%), and secondary exchange (18%). In multivariable models, compared with those obtaining most syringes from "other" sources, those obtaining most syringes from pharmacies had a lower HCV seroprevalence [adjusted prevalence ratio (APR):0.85, 95% confidence interval (CI) 0.73-0.9985]; however, the upper bound of the 95% CI was close to 1.0. Compared with those obtaining most syringes from other sources, PWID obtaining most syringes directly from SSPs or pharmacies were less likely to report borrowing used syringes [APR(SSP):0.60, 95% CI 0.43-0.85 and APR(Pharmacies):0.70, 95% CI 0.52-0.93], borrowing used injection equipment [APR(SSP):0.59, 95% CI 0.50-0.69 and APR (Pharmacies):0.81, 95% CI 0.68-0.98], and backloading [APR(SSP):0.65, 95% CI 0.48-0.88 and APR(Pharmacies):0.78, 95% CI 0.67-0.91]. Potential inverse associations between obtaining most syringes via secondary exchange and injection sharing practices did not reach the threshold for statistical significance.

CONCLUSIONS

PWID in rural New England largely relied on informal syringe sources (i.e., secondary exchange or sources besides SSPs/pharmacies). Those obtaining most syringes from an SSP or pharmacy were less likely to share injection equipment/syringes and had a lower HCV seroprevalence, which suggests using these sources reduces the risk of new HCV infections or serves as proxy for past injection behavior.

Direct-acting antiviral retreatment patterns for hepatitis C

BACKGROUND: Despite the strong efficacy of direct-acting antivirals (DAAs) against the hepatitis C virus, many patients require a second regimen of DAA treatment. However, limited research exists to characterize rates of retreatment across different DAA agents or potential factors that may increase retreatment risk. OBJECTIVE: To characterize patterns and predictors of DAA retreatment among a large, generalizable, commercially insured US population of patients. METHODS: Using the IBM MarketScan Commercial Claims and Encounters data source, this retrospective cohort study examined retreatment patterns among patients receiving DAAs between 2013 and 2019. Descriptive statistics were used to compare patient characteristics predictive of retreatment risk and to examine rates of retreatment in patients initiating different DAA treatments. RESULTS: Among 31,553 DAA users, a total of 1,017 (3.2%) required DAA retreatment. Among the 1,017 patients re-treated, 44 (4.3%) received a third treatment regimen and 2 patients received a fourth treatment regimen. The average total cost for a retreatment regimen was $109,683, with patient out-of-pocket costs totaling $1,287 Patients requiring retreatment had higher rates of hypertension (32.0% vs 26.7%; P < 0.001), diabetes (16.9% vs 11.9%; P < 0.001), coagulopathy (9.9% vs 4.5%; P < 0.001), deficiency anemia (11.1% vs 7.4%; P < 0.001), alcohol abuse (3.3% vs 2.3%; P = 0.038), prior liver transplantation (3.4% vs 2.3%; P = 0.024), and hepatocellular carcinoma (6.1% vs 1.9%; P < 0.001) compared with patients not requiring retreatment. CONCLUSIONS: Although uncommon, some patients receiving DAAs require a second regimen of DAA treatment at substantial cost to both health plans and patients. These patients tend to have more comorbidities and markers of hepatic disease severity. Patients with high retreatment risk may benefit from careful monitoring for occurrences of retreatment.

Hepatitis C virus risk among young people who inject drugs

Background

Injection drug use (IDU) is the leading risk factor for hepatitis C virus (HCV) transmission in the U.S. While the general risk factors for HCV transmission are known, there is limited work on how these factors interact and impact young people who inject drugs (YPWID).

Methods

Project data were drawn from a study of 539 New York City (NYC) residents ages 18-29 who were recruited via Respondent-Driven Sampling and, reported past-month non-medical use of prescription opioids and/or heroin. Analyses are based on a subsample of 337 (62%) who reported injecting any drug in the past 12 months. All variables were assessed via self-report, except HCV status, which was established via rapid antibody testing. Integrating the observed statistical associations with extant literature on HCV risk, we also developed a qualitative system dynamics (SD) model to use as a supplemental data visualization tool to explore plausible pathways and interactions among key risk and protective factors for HCV.

Results

Results showed a 31% HCV antibody prevalence with an overall incidence of 10 per 100 person-years. HCV status was independently correlated with having shared cookers with two or more people (AOR = 2.17); injected drugs 4–6 years (AOR = 2.49) and 7 or more years (AOR = 4.95); lifetime homelessness (AOR = 2.52); and having been incarcerated two or more times (AOR = 1.99). These outcomes along with the extant literature on HCV risk were used to develop the qualitative SD model, which describes a causal hypothesis around non-linearities and feedback loop structures underlying the spread of HCV among YPWID.

Conclusions

Despite ongoing harm reduction efforts, close to a third of YPWID in the community sample have been exposed to HCV, have risks for injection drug use, and face challenges with structural factors that may be preventing adequate intervention. The qualitative SD model explores these issues and contributes to a better understanding of how these various risk factors interact and what policies could potentially be effective in reducing HCV infections.

Availability of opioid agonist treatment and critical incidents in Forensic Clinics for Dependency Diseases in Germany

BACKGROUND

Prevalence of substance use disorders, especially opioid use disorders, is high in patients admitted into forensic psychiatric settings. Opioid agonist treatment is a safe, well-established, and effective treatment option for patients that suffer from opioid dependence. Surprisingly, data on the availability and practice of opioid agonist treatment (OAT) options in German Forensic Clinics for Dependency Diseases is rare. Furthermore, essential data on the prevalence of critical incidents such as violent behavior, relapse, or escape from the clinic are missing for this particular treatment setting.

MATERIALS AND METHODS

We conducted an observational study on all forensic addiction treatment units in Germany (Sect. 64 of the German Criminal Code). A questionnaire on the availability and practice of OAT was sent to all Forensic Clinics for Dependency Diseases in Germany. Following items were assessed: availability and the total number of patients that received an OAT in 2018, available medication options, specific reasons for start and end of OAT, number of treatments terminated without success, number of successful treatments, and critical incidents such as violent behavior, relapse, escape and reoffending. We compared the forensic clinics that offered OAT with those that did not offer this treatment option. The data were analyzed descriptively. Mean and standard deviation was calculated for metric scaled variables. For categorical variables, absolute and relative frequencies were calculated. The two groups (OAT vs. Non-OAT institutions) were compared concerning the given variables by either using Fishers exact test (categorical variables), t-test (normally distributed metric variables), or Wilcoxon-test (metric variables not normally distributed).

RESULTS

In total, 15 of 46 Forensic Clinics for Dependency Diseases participated in the study (33%). In total, 2,483 patients were treated in the participating clinics, 18% were relocated into prison due to treatment termination, and 15% were discharged successfully in 2018. 275 critical incidents were reported: violence against a patient (4%), violence against staff (1.6%), escape (4.7%) and reoffending in (0.5%). In seven clinics treating 1,153 patients, an OAT was available. OAT options in forensic clinics were buprenorphine/naloxone, buprenorphine, methadone, and levomethadone. Regarding critical incidents and successful discharge, no differences were detected in the clinics with or without an OAT. In the clinics that offered an OAT, we found a significantly higher rate of treatment termination without success (p < 0.007) in comparison to clinics without an OAT program. Ninety-nine patients received an OAT, and this treatment was ended due to illegal drug abuse (57%), refusal to give a urine drug sample (71%), and cases where the OAT was given away to other patients (85%).

CONCLUSION

In Forensic Clinics for Dependency Diseases in Germany, OAT is not available in every institution, and thus, access is limited. Critical incidents such as violent behavior against staff or patients and escape are not uncommon in these forensic treatment settings. Further studies are needed to enhance the understanding of OAT practice and the risks for patients and staff.

Cost-effectiveness of syringe service programs, medications for opioid use disorder, and combination programs in hepatitis C harm reduction among opioid injection drug users: a public payer perspective using a decision tree

BACKGROUND: The hepatitis C virus (HCV) prevalence rate among injection drug users (IDUs) in North America is 55.2%, with 1.41 million individuals estimated to be HCV-antibody positive. Studies have shown the effectiveness of syringe service programs (SSPs) alone, medications for opioid use disorder (MOUD) alone, or SSP+MOUD combination in reducing HCV transmission among opioid IDUs. OBJECTIVE: To evaluate the cost-effectiveness of SSP alone, MOUD alone, and SSP + MOUD combination in preventing HCV cases among opioid IDUs in the United States. METHODS: We used a decision tree analysis model based on published literature and publicly available data. Effectiveness was presented as the number of HCV cases avoided per 100 opioid IDUs. A micro-costing approach was undertaken and included both direct medical and nonmedical costs. Cost-effectiveness was assessed from a public payer perspective over a 1-year time horizon. It was expressed as an incremental cost-effectiveness ratio (ICER) and an incremental cost savings per HCV case avoided per 100 opioid IDUs compared with cost savings with "no intervention." Costs were standardized to 2019 U.S. dollars. RESULTS: The incremental cost savings per HCV case avoided per 100 opioid IDUs compared with no intervention were as follows: SSP + MOUD combination = $347,573; SSP alone = $363,821; MOUD alone = $317,428. The ICER for the combined strategy was $4,699 compared with the ICER for the SSP group. Sensitivity analysis showed that the results of the base-case cost-effectiveness analysis were sensitive to variations in the probabilities of injection-risk behavior for the SSP and SSP + MOUD combination groups, probability of no HCV with no intervention, and costs of MOUD and HCV antiviral medications. CONCLUSIONS: The SSP + MOUD combination and SSP alone strategies dominate MOUD alone and no intervention strategies. SSP had the largest incremental cost savings per HCV case avoided per 100 opioid IDUs compared with the no intervention strategy. Public payers adopting the SSP + MOUD combination harm-reduction strategy instead of SSP alone would have to pay an additional $4,699 to avoid an additional HCV case among opioid IDUs. Although these harm-reduction programs will provide benefits in a 1-year time frame, the largest benefit may become evident in the years ahead. DISCLOSURES: This research had no external funding. The authors declare no financial interests in this article. Ijioma is a Health Economics and Outcomes Research (HEOR) postdoctoral Fellow with Virginia Commonwealth University and Indivior. Indivior is a pharmaceutical manufacturer of opioid addiction treatment drugs but was not involved in the design, analysis, or write-up of the manuscript.

Elimination of hepatitis C among HIV-positive population in Asia: old and new challenges

Hepatitis C virus (HCV) prevalence is high among people living with HIV co-infected with HCV, people who inject drugs, men who have sex with men and inmates in correctional settings. The barriers to eliminate HCV among these key populations include diagnosis challenges, lack of awareness, discrimination and stigmatization. In addition, scaling up of HCV treatment has been a challenge in Asia–Pacific with the lack of national policies, targets and unavailability of appropriate direct-acting antivirals regimens. In order to achieve HCV micro elimination within these high-risk populations, novel strategies to improve the cascade of care from diagnosis to treatment with direct-acting antivirals, complemented by behavioral change interventions, harm reduction services for people who inject drugs, civil society led advocacy and policies from the government, will be necessary.

The Relationship Between Hepatitis C Virus Rates and Office-Based Buprenorphine Access in Ohio

Background

The United States is experiencing an epidemic of hepatitis C virus (HCV) infections due to injection drug use, primarily of opioids and predominantly in rural areas. Buprenorphine, a medication for opioid use disorder, may indirectly prevent HCV transmission. We assessed the relationship of HCV rates and office-based buprenorphine prescribing in Ohio.

Methods

We conducted an ecological study of the county-level (n = 88) relationship between HCV case rates and office-based buprenorphine prescribing in Ohio. We fit adjusted negative binomial models between the county-level acute and total HCV incidence rates during 2013–2017 and 1) the number of patients in each county that could be served by office-based buprenorphine (prescribing capacity) and 2) the number served by office-based buprenorphine (prescribing frequency) from January–March, 2018.

Results

For each 10% increase in acute HCV rate, office-based buprenorphine prescribing capacity differed by 1% (95% CI: –1%, 3%). For each 10% increase in total HCV rate, office-based buprenorphine prescribing capacity was 12% (95% CI: 7%, 17%) higher. For each 10% increase in acute HCV rate, office-based buprenorphine prescribing frequency was 1% (95% CI: –1%, 3%) higher. For each 10% increase in total HCV rate, office-based buprenorphine prescribing frequency was 14% (95% CI: 7%, 20%) higher.

Conclusions

Rural counties in Ohio have less office-based buprenorphine and higher acute HCV rates versus urban counties, but a similar relationship between office-based buprenorphine prescribing and HCV case rates. To adequately prevent and control HCV rates, certain rural counties may need more office-based buprenorphine prescribing in areas with high HCV case rates.

Homelessness, unstable housing, and risk of HIV and hepatitis C virus acquisition among people who inject drugs: a systematic review and meta-analysis

BACKGROUND

People who inject drugs (PWID) are at increased risk for HIV and hepatitis C virus (HCV) infection and also have high levels of homelessness and unstable housing. We assessed whether homelessness or unstable housing is associated with an increased risk of HIV or HCV acquisition among PWID compared with PWID who are not homeless or are stably housed.

METHODS

In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies published between Jan 1, 2000, and June 13, 2017. Using the same strategy as for this existing database, we searched MEDLINE, Embase, and PsycINFO for studies, including conference abstracts, published between June 13, 2017, and Sept 14, 2020, that estimated HIV or HCV incidence, or both, among community-recruited PWID. We only included studies reporting original results without restrictions to study design or language. We contacted authors of studies that reported HIV or HCV incidence, or both, but did not report on an association with homelessness or unstable housing, to request crude data and, where possible, adjusted effect estimates. We extracted effect estimates and pooled data using random-effects meta-analyses to quantify the associations between recent (current or within the past year) homelessness or unstable housing compared with not recent homelessness or unstable housing, and risk of HIV or HCV acquisition. We assessed risk of bias using the Newcastle-Ottawa Scale and between-study heterogeneity using the I2 statistic and p value for heterogeneity.

FINDINGS

We identified 14 351 references in our database search, of which 392 were subjected to full-text review alongside 277 studies from our existing database. Of these studies, 55 studies met inclusion criteria. We contacted the authors of 227 studies that reported HIV or HCV incidence in PWID but did not report association with the exposure of interest and obtained 48 unpublished estimates from 21 studies. After removal of duplicate data, we included 37 studies with 70 estimates (26 for HIV; 44 for HCV). Studies originated from 16 countries including in North America, Europe, Australia, east Africa, and Asia. Pooling unadjusted estimates, recent homelessness or unstable housing was associated with an increased risk of acquiring HIV (crude relative risk [cRR] 1·55 [95% CI 1·23-1·95; p=0·0002]; I2= 62·7%; n=17) and HCV (1·65 [1·44-1·90; p<0·0001]; I2= 44·8%; n=28]) among PWID compared with those who were not homeless or were stably housed. Associations for both HIV and HCV persisted when pooling adjusted estimates (adjusted relative risk for HIV: 1·39 [95% CI 1·06-1·84; p=0·019]; I2= 65·5%; n=9; and for HCV: 1·64 [1·43-1·89; p<0·0001]; I2= 9·6%; n=14). For risk of HIV acquisition, the association for unstable housing (cRR 1·82 [1·13-2·95; p=0·014]; n=5) was higher than for homelessness (1·44 [1·13-1·83; p=0·0036]; n=12), whereas no difference was seen between these outcomes for risk of HCV acquisition (1·72 [1·48-1·99; p<0·0001] for unstable housing, 1·66 [1·37-2·00; p<0·0001] for homelessness).

INTERPRETATION

Homelessness and unstable housing are associated with increased risk of HIV and HCV acquisition among PWID. Our findings support the development of interventions that simultaneously address homelessness and unstable housing and HIV and HCV transmission in this population.

FUNDING

National Institute for Health Research, National Institute on Drug Abuse, National Institute of Allergy and Infectious Diseases, and Commonwealth Scholarship Commission.

Changes in substance supply and use characteristics among people who use drugs (PWUD) during the COVID-19 global pandemic: A national qualitative assessment in Canada

BACKGROUND

People who use drugs (PWUD) may be at an increased risk of experiencing negative effects related to COVID-19. Border and non-essential service closures may have placed PWUD at an increased risk of experiencing unintended consequences regarding drug consumption and supply patterns, as well as related outcomes. However, the extent of these effects upon this population is unknown. The current study examined how COVID-19 has impacted substance use supply and use characteristics among a national cohort of PWUD in Canada.

METHODS

We conducted semi-structured one-on-one telephone-based interviews with 200 adult PWUD across Canada who were currently using a licit or illicit psychoactive substance at least weekly, and/or currently receiving opioid agonist treatment (OAT). Thematic analyses were conducted using qualitative software.

RESULTS

PWUD attributed adverse changes to their substance use frequency, supply, use patterns, and risk behaviors and outcomes to COVID-19. Many participants noted supply disruptions with the majority indicating a decrease in potency and availability, and an increase in the price of substances since COVID-19. Nearly half of participants specified that they had increased their substance use, with some experiencing relapses. In terms of changes to risk level, many participants perceived they were at a greater risk for experiencing an overdose.

CONCLUSION

This study demonstrated the impacts of COVID-19 on PWUD, including a significant disruption substance supply. For many, these changes led to increased use and substitution for toxic and adulterated substances, which ultimately amplified PWUD's risk for experiencing related harms, including overdoses. These findings warrant the need for improved supports and services, as well as accessibility of safe supply programs, take home naloxone kits, and novel approaches to ensure PWUD have the tools necessary to mitigate risk when using substances.

Low Hepatitis C Reinfection Following Direct-acting Antiviral Therapy Among People Who Inject Drugs on Opioid Agonist Therapy

BACKGROUND

Direct-acting antiviral (DAA) therapy is highly effective in people who inject drugs (PWID); however, rates, specific injection behaviors, and social determinants associated with hepatitis C virus (HCV) reinfection following DAA therapy among PWID on opioid agonist therapy (OAT) are poorly understood.

METHODS

PREVAIL was a randomized controlled trial that assessed models of HCV care for 150 PWID on OAT. Those who achieved sustained virologic response (SVR) (n = 141; 94%) were eligible for this extension study. Interviews and assessments of recurrent HCV viremia occurred at 6-month intervals for up to 24 months following PREVAIL. We used survival analysis to analyze variables associated with time to reinfection.

RESULTS

Of 141 who achieved SVR, 114 had a least 1 visit in the extension study (62% male; mean age, 52 years). Injection drug use (IDU) was reported by 19% (n = 22) in the extension study. HCV reinfection was observed in 3 participants. Over 246 person-years of follow-up, the incidence of reinfection was 1.22/100 person-years (95% CI, 0.25-3.57). All reinfections occurred among participants reporting ongoing IDU. The incidence of reinfection in participants reporting ongoing IDU (41 person-years of follow-up) was 7.4/100 person-years (95% CI, 1.5-21.6). Reinfection was associated with reporting ongoing IDU in the follow-up period (P < .001), a lack confidence in the ability to avoid contracting HCV (P < .001), homelessness (P = .002), and living with a PWID (P = .007).

CONCLUSIONS

HCV reinfection was low overall, but more common among people with ongoing IDU following DAA therapy on OAT, as well as those who were not confident in the ability to avoid contracting HCV, homeless, or living with a PWID. Interventions to mediate these risk factors following HCV therapy are warranted.

Housing Stability and Hepatitis C Infection for Young Adults Who Inject Drugs: Examining the Relationship of Consistent and Intermittent Housing Status on HCV Infection Risk

Housing status affects drug using behaviors, but less is known about the relationship between housing patterns and hepatitis C virus (HCV) infection. HCV-negative young people who inject drugs (PWID) were enrolled into a prospective cohort (2003-2019) with quarterly study visits. We used Cox regression to estimate the independent association of recent housing status (housed vs. unhoused, housing stability, and housing trajectory) on HCV incidence. Among 712 participants, 245 incident HCV infections occurred over 963.8 person-years (py) (cumulative incidence 24.4/100 py). An inverse relationship between time housed and HCV incidence was observed (always unhoused 45.0/100 py, 95% confidence interval (CI) 37.1, 54.5; variably housed 18.0/100 py, 95% CI 15.0, 21.3; and always housed 7.0/100 py, 95% CI 3.0, 17.3). In Cox regression models controlling for confounders, those unhoused versus housed at baseline had a 1.9-fold increased infection risk (95% CI 1.4, 2.6). Those always unhoused versus always housed had a 1.5 times greater risk of HCV (95% CI 1.0, 2.3), and those spending a portion of time in stable housing a lower risk (adjusted relative hazard 0.05, 95% CI 0.3, 0.9) with a similar trend for those being housed for less time. Young adult PWID experiencing both recent and chronic states of being unhoused are at elevated risk for HCV infection. Importantly for this group of PWID, our findings indicate that some frequency of residential housing significantly reduces HCV infection risk.

Understanding the crisis in harm reduction funding in Central and Eastern Europe

Background

The harm reduction (HR) approach to injecting drug use was rapidly adopted in Central Europe following the fall of the Iron Curtain. The associated social and economic transformation had significant consequences for drug policies in the region. A large number of emerging services have been dependent on funding from a wide range of national and/or local funding programmes, which continue to be unstable, and closely associated with political decisions and insufficient institution building. A sharp distinction is made between health and social services, often without regard to client input. The main objective of the paper is to identify the causes of the funding problems currently faced by HR services in the context of their history of institution building which represents a major threat to the future of HR services in the region.

Methods

Qualitative content analysis of documents was conducted in the development of two case studies of the Czech and Slovak Republics. The body of documentation under study comprised policy documents, including National Drug Strategies, Action Plans, ministerial documents, and official budgets and financial schedules, as well as documents from the grey literature and expert opinions.

Results

The insufficient investments in finalising the process of the institution building of HR services have resulted in a direct threat to their sustainability. An unbalanced inclination to the institutionalisation of HR within the domain of social services has led to a misperception of their integrity, as well as to their funding and long-term sustainability being endangered. In addition, this tendency has had a negative impact on the process of the institutionalisation of HR within the system of healthcare.

Conclusion

The case study revealed a lack of systemic grounding of HR services as interdisciplinary health-social services. The aftermath of the financial crisis in 2008 fully revealed the limitations of the funding system established ad hoc in the 1990s, which remains present until today, together with all its weak points. The entire situation is responsible for the dangerous erosion of the interpretation of the concept of harm reduction, which is supported by various stereotypes and false, or ideological, interpretations of the concept.

Prevalence of Opioid Dependence and Opioid Agonist Treatment in the Berlin Custodial Setting: A Cross-Sectional Study

BACKGROUND

Among people living in detention, substance use is highly prevalent, including opioid dependence. Opioid agonist treatment (OAT) has been established as an evidence-based, first-line treatment for opioid dependence. Despite high prevalence of opioid dependence, conclusive data regarding its prevalence and the OAT practice in German prisons is scarce; rather, the existing data widely diverges concerning the rates of people in detention receiving OAT.

MATERIALS AND METHODS

We conducted a cross-sectional survey of all detention facilities in Berlin. On the date of data collection, a full census of the routine records was completed based on the medical documentation system. For each opioid dependent individual, we extracted sociodemographic data (i.e., age, sex, and non-/German nationality, whether people experienced language-related communication barriers), information about OAT, comorbidities (HIV, hepatitis C, schizophrenia), and the detention center, as well as the anticipated imprisonment duration and sentence type. The data was first analyzed descriptively and secondly in an evaluative-analytical manner by analyzing factors that influence the access to OAT of people living in detention.

RESULTS

Among the 4,038 people in detention in the Berlin custodial setting under investigation, we identified a 16% prevalence of opioid dependence. Of the opioid-dependent individuals, 42% received OAT; 31% were treated with methadone, 55% were treated with levomethadone, and 14% were treated with buprenorphine. Access to OAT seemed mainly dependent upon initial receipt of OAT at the time of imprisonment, detention duration, the prisons in which individuals were detained, German nationality, and sex. The overall prevalence of HIV was 4-8%, hepatitis C was 31-42%, and schizophrenia was 5%.

CONCLUSIONS

The prevalence of opioid dependence and access to OAT remains a major health issue in the custodial setting. OAT implementation must be especially intensified among male, non-German, opioid-dependent individuals with a short detention period. Treatment itself must be diversified regarding the substances used for OAT, and institutional treatment differences suggest the need for a consistent treatment approach and the standardized implementation of treatment guidelines within local prison's standard operating procedures. Testing for infectious diseases should be intensified among opioid-dependent people living in detention to address scarcely known infection statuses and high infection rates.

Community Screening, Identification, and Referral to Primary Care, for Hepatitis C, B, and HIV Among Homeless Persons in Los Angeles

People experiencing homelessness are disproportionally affected by drug and alcohol use and by their serious health consequences. In this study, 137 adults from the "UCLA/ARG/RAND Homeless Hepatitis Study" who were sampled from shelters and meal programs in the Skid Row of Los Angeles and screened for HIV or HCV or HBV infection. Those who tested positive for these infections were counseled about their infections and referred to primary care. They were followed-up at 1 month with interviews to identify rates, and predictors, of seeking primary care. Participants were 87.5% male, mean age of 48.6 years (SD: 8.2); most were Black (77.4%) and were chronically homeless (> 12 months). A majority (70%) had a regular source of care; 78% were lifetime marijuana users, 56% were lifetime cocaine users and 51% had injected intravenously during the past year. Among this sample, 118 participants (86.1%) tested seropositive for HCV infection, 79 (57.7%) HBV infection and 18 (13.1%) HIV infection. At 1-month follow-up, 102 participants (74.5%) attended the clinic they were referred to. The only variable associated with attending the clinic was having slept in a shelter during the previous night versus other sleeping conditions [Odds ratio (95% CI): 3 .0 (1.07-8.42), p = 0.03]. This model offers a simple and efficacious approach to seeking, testing, counseling, and referral to treatment of community-based adults experiencing homelessness with HIV, HCV and/or HBV infection and linking them to primary care. Being sheltered may be the key facilitator for homeless seeking primary care.

Hepatitis C virus testing, liver disease assessment and direct-acting antiviral treatment uptake and outcomes in a service for people who are homeless in Sydney, Australia: The LiveRLife homelessness study

People who are homeless have increased hepatitis C virus (HCV) infection risk, and are less likely to access primary healthcare. We aimed to evaluate HCV RNA prevalence, liver disease burden, linkage to care and treatment uptake and outcomes among people attending a homelessness service in Sydney. Participants were enrolled in an observational cohort study with recruitment at a homelessness service over eight liver health campaign days. Finger-stick whole-blood samples for Xpert® HCV Viral Load and venepuncture blood samples were collected. Participants completed a self-administered survey and received transient elastography and clinical assessment by a general practitioner or nurse. Clinical follow-up was recommended 2-12 weeks after enrolment. For participants initiating direct-acting antiviral (DAA) therapy, medical records were audited retrospectively and treatment outcome data were collected. Among 202 participants (mean age, 48 years), 82% were male (n = 165), 39% (n = 78) reported ever injecting drugs, of whom 63% (n = 49) injected in the previous month. Overall, 23% (n = 47) had detectable HCV RNA and 6% (n=12) had cirrhosis. HCV RNA prevalence among participants with either injecting or incarceration history was 35% (37/105), compared to 4% (3/73) among participants without these risk factors. Among those with detectable HCV RNA, 23 (49%) commenced therapy, of whom 65% (n = 15) achieved sustained virological response, while the remainder had no available treatment outcome. No participant had documented virological failure. HCV DAA treatment uptake among people attending a homelessness service was encouraging, but innovative models of HCV care are required to improve linkage to care and treatment uptake among this highly marginalized population.

The distribution and socioeconomic burden of Hepatitis C virus in South Australia: a cross-sectional study 2010-2016

Background

Hepatitis C virus infection (HCV) is a communicable disease of increasing global importance with 1.75 million new infections and 400,000 related deaths annually. Until recently, treatment options have had low uptake and most infected people remain untreated. New Direct Acting Antiviral medications can clear the virus in around 95% of cases, with few side-effects. These medications are restricted in most countries but freely accessible in Australia, yet most people still remain untreated. This study applies a cross-sectional research design to investigate the socio-spatial distribution of HCV in South Australia, to identify vulnerable populations, and examine epidemiological factors to potentially inform future targeted strategies for improved treatment uptake.

Method

HCV surveillance data were sourced from South Australia’s Communicable Diseases Control Branch and socio-economic population data from the Australian Bureau of Statistics from January 2010 to December 2016 inclusive. HCV cases were spatially mapped at postcode level. Multivariate logistic regression identified independent predictors of demographic risks for HCV notification and notification source.

Results

HCV notifications (n = 3356) were seven times more likely to be from people residing in the poorest areas with high rates of non-employment (75%; n = 1876) and injecting drug use (74%; n = 1862) reported. Notifications among Aboriginal and Torres Strait Islander people were around six times that of non-Indigenous people. HCV notifications negatively correlated (Spearman’s rho − 0.426; p < 0.001) with socio-economic status (residential postcode socio-economic resources Index). History of imprisonment independently predicted HCV diagnoses in lesser economically-resourced areas (RR1.5; p < 0.001). Independent predictors of diagnosis elsewhere than in general practices were non-employment (RR 4.6; p = 0.028), being male (RR 2.5; p < 0.001), and younger than mean age at diagnosis (RR 2.1; p = 0.006).

Conclusions

Most people diagnosed with HCV were from marginalised sub-populations. Given general practitioners are pivotal to providing effective HCV treatment for many people in Australia a most concerning finding was that non-employed people were statistically less likely to be diagnosed by general practitioners. These findings highlight a need for further action aimed at improving healthcare access and treatment uptake to help reduce the burden of HCV for marginalised people, and progress the vision of eliminating HCV as a major public health threat.

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

Background

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.

Methods

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.

Results

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%).

Conclusions

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.

Incarceration history and risk of HIV and hepatitis C virus acquisition among people who inject drugs: a systematic review and meta-analysis

BACKGROUND

People who inject drugs (PWID) experience a high prevalence of incarceration and might be at high risk of HIV and hepatitis C virus (HCV) infection during or after incarceration. We aimed to assess whether incarceration history elevates HIV or HCV acquisition risk among PWID.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, and PsycINFO databases for studies in any language published from Jan 1, 2000 until June 13, 2017 assessing HIV or HCV incidence among PWID. We included studies that measured HIV or HCV incidence among community-recruited PWID. We included only studies reporting original results and excluded studies that evaluated incident infections by self-report. We contacted authors of cohort studies that met the inclusion or exclusion criteria, but that did not report on the outcomes of interest, to request data. We extracted and pooled data from the included studies using random-effects meta-analyses to quantify the associations between recent (past 3, 6, or 12 months or since last follow-up) or past incarceration and HIV or HCV acquisition (primary infection or reinfection) risk among PWID. We assessed the risk of bias of included studies using the Newcastle-Ottawa Scale. Between-study heterogeneity was evaluated using the I2 statistic and the P-value for heterogeneity.

FINDINGS

We included published results from 20 studies and unpublished results from 21 studies. These studies originated from Australasia, western and eastern Europe, North and Latin America, and east and southeast Asia. Recent incarceration was associated with an 81% (relative risk [RR] 1·81, 95% CI 1·40-2·34) increase in HIV acquisition risk, with moderate heterogeneity between studies (I2=63·5%; p=0·001), and a 62% (RR 1·62, 95% CI 1·28-2·05) increase in HCV acquisition risk, also with moderate heterogeneity between studies (I2=57·3%; p=0·002). Past incarceration was associated with a 25% increase in HIV (RR 1·25, 95% CI 0·94-1·65) and a 21% increase in HCV (1·21, 1·02-1·43) acquisition risk.

INTERPRETATION

Incarceration is associated with substantial short-term increases in HIV and HCV acquisition risk among PWID and could be a significant driver of HCV and HIV transmission among PWID. These findings support the need for developing novel interventions to minimise the risk of HCV and HIV acquisition, including addressing structural risks associated with drug laws and excessive incarceration of PWID.

FUNDING

Engineering and Physical Sciences Research Council, National Institute for Health Research, National Institutes of Health.

A comparison of two biological markers of recent hepatitis C virus (HCV) infection: implications for the monitoring of interventions and strategies to reduce HCV transmission among people who inject drugs

BackgroundMonitoring hepatitis C virus (HCV) incidence is important for assessing intervention impact. Longitudinal studies of people who inject drugs (PWID), using repeated biological tests, are costly; alternatively, incidence can be estimated using biological markers of recent infection in cross-sectional studies.AimWe aimed to compare incidence estimates obtained from two different biological markers of recent infection in a cross-sectional study to inform monitoring approaches for HCV elimination strategies.MethodSamples from an unlinked anonymous bio-behavioural survey of PWID were tested for two recent infection markers: HCV RNA with anti-HCV negative ('RNA') and low-avidity anti-HCV with HCV RNA present ('avidity'). These two markers were used separately and in combination to estimate HCV incidence.ResultsBetween 2011 and 2013, 2,816 anti-HIV-negative PWID (25% female) who had injected during the preceding year were either HCV-negative or had one of the two markers of recent infection: 57 (2.0%) had the RNA marker and 90 (3.2%) the avidity marker. The two markers had similar distributions of risk and demographic factors. Pooled estimated incidence was 12.3 per 100 person-years (pyrs) (95% credible interval: 8.8-17.0) and not significantly different to avidity-only (p = 0.865) and RNA-only (p = 0.691) estimates. However, the RNA marker is limited by its short duration before anti-HCV seroconversion and the avidity marker by uncertainty around its duration.ConclusionBoth markers have utility in monitoring HCV incidence among PWID. When HCV transmission is high, one marker may provide an accurate estimate of incidence; when it is low or decreasing, a combination may be required.

Hepatitis C among vulnerable populations: A seroprevalence study of homeless, people who inject drugs and prisoners in London

Injecting drugs substantially increases the risk of hepatitis C virus (HCV) infection and is common in the homeless and prisoners. Capturing accurate data on disease prevalence within these groups is challenging but is essential to inform strategies to reduce HCV transmission. The aim of this study was to estimate the prevalence of HCV in these populations. We conducted a cross-sectional study between May 2011 and June 2013 in London and, using convenience sampling, recruited participants from hostels for the homeless, drug treatment services and a prison. A questionnaire was administered and blood samples were tested for hepatitis C. We recruited 491 individuals who were homeless (40.7%), 205 drug users (17%) and 511 prisoners (42.3%). Eight per cent of patients (98/1207, 95% CI: 6.7%-9.8%) had active HCV infection and 3% (38/1207, 95% CI: 2.3%-4.3%) past HCV infection. Overall, one quarter (51/205) of people recruited in drug treatment services, 13% (65/491) of people from homeless residential sites and 4% (20/511) prisoners in this study were anti-HCV positive. Seventy-seven of the 136 (56.6%, 95% CI: 47.9%-65%) of HCV infected participants identified had a history of all three risk factors (homelessness, imprisonment and drug use), 27.3% (95% CI: 20.1%-35.6%) had 2 overlapping risk factors, and 15.4% (95% CI: 10.6%-23.7%) one risk factor. Drug treatment services, prisons and homelessness services provide good opportunities for identifying hepatitis C-infected individuals. Effective models need to be developed to ensure case identification in these settings that can lead to an effective treatment and an efficient HCV prevention.

Impact of current and scaled-up levels of hepatitis C prevention and treatment interventions for people who inject drugs in three UK settings-what is required to achieve the WHO's HCV elimination targets?

AIMS

To estimate the impact of existing high-coverage needle and syringe provision (HCNSP, defined as obtaining more than one sterile needle and syringe per injection reported) and opioid substitution therapy (OST) on hepatitis C virus (HCV) transmission among people who inject drugs (PWID) in three UK settings and to determine required scale-up of interventions, including HCV treatment, needed to reach the World Health Organization (WHO) target of reducing HCV incidence by 90% by 2030.

DESIGN

HCV transmission modelling using UK empirical estimates for effect of OST and/or HCNSP on individual risk of HCV acquisition.

SETTING AND PARTICIPANTS

Three UK cities with varying chronic HCV prevalence (Bristol 45%, Dundee 26%, Walsall 19%), OST (72-81%) and HCNSP coverage (28-56%).

MEASUREMENTS

Relative change in new HCV infections throughout 2016-30 if current interventions were stopped. Scale-up of HCNSP, OST and HCV treatment required to achieve the WHO elimination target.

FINDINGS

Removing HCNSP or OST would increase the number of new HCV infections throughout 2016 to 2030 by 23-64 and 92-483%, respectively. Conversely, scaling-up these interventions to 80% coverage could achieve a 29 or 49% reduction in Bristol and Walsall, respectively, whereas Dundee may achieve a 90% decrease in incidence with current levels of intervention because of existing high levels of HCV treatment (47-58 treatments per 1000 PWID). If OST and HCNSP are scaled-up, Walsall and Bristol can achieve the same impact by treating 14 or 40 per 1000 PWID annually, respectively (currently two and nine treatments per 1000 PWID), while 18 and 43 treatments per 1000 PWID would be required if OST and HCNSP are not scaled-up.

CONCLUSIONS

Current opioid substitution therapy and high-coverage needle and syringe provision coverage is averting substantial hepatitis C transmission in the United Kingdom. Maintaining this coverage while getting current drug injectors onto treatment can reduce incidence by 90% by 2030.

Understanding and addressing hepatitis C reinfection in the oral direct-acting antiviral era

The availability of effective, simple, well-tolerated oral direct-acting antiviral (DAA) hepatitis C regimens has raised optimism for hepatitis C virus (HCV) elimination at the population level. HCV reinfection in key populations such as people who inject drugs (PWID) and HIV-infected men who have sex with men (MSM) however threatens the achievement of this goal from a patient, provider and population perspective. The goal of this review was to synthesize our current understanding of estimated rates and factors associated with HCV reinfection. This review also proposes interventions to aid understanding of and reduce hepatitis C reinfection among PWID and HIV-infected MSM in the oral direct-acting antiviral era.

Needle and syringe programmes and opioid substitution therapy for preventing HCV transmission among people who inject drugs: findings from a Cochrane Review and meta-analysis

AIMS

To estimate the effects of needle and syringe programmes (NSP) and opioid substitution therapy (OST), alone or in combination, for preventing acquisition of hepatitis C virus (HCV) in people who inject drugs (PWID).

METHODS

Systematic review and meta-analysis. Bibliographic databases were searched for studies measuring concurrent exposure to current OST (within the last 6 months) and/or NSP and HCV incidence among PWID. High NSP coverage was defined as regular NSP attendance or ≥ 100% coverage (receiving sufficient or greater number of needles and syringes per reported injecting frequency). Studies were assessed using the Cochrane risk of bias in non-randomized studies tool. Random-effects models were used in meta-analysis.

RESULTS

We identified 28 studies (n = 6279) in North America (13), United Kingdom (five), Europe (four), Australia (five) and China (one). Studies were at moderate (two), serious (17) critical (seven) and non-assessable risk of bias (two). Current OST is associated with 50% [risk ratio (RR) =0.50, 95% confidence interval (CI) = 0.40-0.63] reduction in HCV acquisition risk, consistent across region and with low heterogeneity (I2  = 0, P = 0.889). Weaker evidence was found for high NSP coverage (RR = 0.79, 95% CI = 0.39-1.61) with high heterogeneity (I2  = 77%, P = 0.002). After stratifying by region, high NSP coverage in Europe was associated with a 56% reduction in HCV acquisition risk (RR = 0.44, 95% CI = 0.24-0.80) with low heterogeneity (I2  = 12.3%, P = 0.337), but not in North America (RR = 1.58, I2  = 89.5%, P = < 0.001). Combined OST/NSP is associated with a 74% reduction in HCV acquisition risk (RR = 0.26, 95% CI = 0.07-0.89, I2  = 80% P = 0.007). According to Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria, the evidence on OST and combined OST/NSP is low quality, while NSP is very low.

CONCLUSIONS

Opioid substitution therapy reduces risk of hepatitis C acquisition and is strengthened in combination with needle and syringe programmes (NSP). There is weaker evidence for the impact of needle syringe programmes alone, although stronger evidence that high coverage is associated with reduced risk in Europe.

Incidence and Risk Factors for Hepatitis C Virus Infection among Illicit Drug Users in Italy

So far, only three small outdated studies have investigated hepatitis C virus (HCV) incidence and risk factors among illicit drug users (DUs) in Italy. Thus, during 2007-2010, we conducted a prospective cohort study among DUs attending 17 Italian rehabilitation centers serving urban areas. Two hundred eighty-four HCV-uninfected DUs were prospectively followed by interview and anti-HCV antibody and RNA testing every 6 months. Incidence was calculated using the person-years method. Infection predictors were assessed by time-dependent Cox analysis. Participants were mostly male (83.4%), under opioid substitution therapy (OST) (78.9%), non-injecting DUs (67.9%), and with a mean age of 30.8. Ninety-one of 224 DUs initially under OST interrupted treatment during the follow-up. Overall HCV incidence was 5.83/100 person-years at risk (PYAR) [95% confidence intervals (CI), 3.63-9.38]. The incidence did not significantly differ according the participants' sociodemographic characteristics or the degree of urbanization of the towns involved in the study. The incidence was higher for DUs under than for those not under OST (6.23 vs 4.50/100 PYAR; p = 0.681). Incidence was also higher for those with than for those without OST interruption (7.17 vs 5.04/100 PYAR; p = 0.55). However, all these differences were non-significant. At last follow-up visit, a significant decrease in frequency of sharing equipment for preparation/using drugs (by injection or not) was observed by analyzing either the whole cohort or DUs under OST only. Anti-HCV seroconversion resulted independently associated with sharing drug preparation/use equipment, backloading, having a HCV-positive sexual partner, or household and (marginally) intravenous injection. In this study, HCV incidence was non-negligible and OST seemed to lack effectiveness in reducing it. In Italy, implementation of combined harm reduction interventions and antiviral treatment of chronically infected DUs would be needed.

Needle syringe programmes and opioid substitution therapy for preventing hepatitis C transmission in people who inject drugs

BACKGROUND

Needle syringe programmes and opioid substitution therapy for preventing hepatitis C transmission in people who inject drugsNeedle syringe programmes (NSP) and opioid substitution therapy (OST) are the primary interventions to reduce hepatitis C (HCV) transmission in people who inject drugs. There is good evidence for the effectiveness of NSP and OST in reducing injecting risk behaviour and increasing evidence for the effectiveness of OST and NSP in reducing HIV acquisition risk, but the evidence on the effectiveness of NSP and OST for preventing HCV acquisition is weak.

OBJECTIVES

To assess the effects of needle syringe programmes and opioid substitution therapy, alone or in combination, for preventing acquisition of HCV in people who inject drugs.

SEARCH METHODS

We searched the Cochrane Drug and Alcohol Register, CENTRAL, the Cochrane Database of Systematic Reviews (CDSR), the Database of Abstracts of Reviews of Effects (DARE), the Health Technology Assessment Database (HTA), the NHS Economic Evaluation Database (NHSEED), MEDLINE, Embase, PsycINFO, Global Health, CINAHL, and the Web of Science up to 16 November 2015. We updated this search in March 2017, but we have not incorporated these results into the review yet. Where observational studies did not report any outcome measure, we asked authors to provide unpublished data. We searched publications of key international agencies and conference abstracts. We reviewed reference lists of all included articles and topic-related systematic reviews for eligible papers.

SELECTION CRITERIA

We included prospective and retrospective cohort studies, cross-sectional surveys, case-control studies and randomised controlled trials that measured exposure to NSP and/or OST against no intervention or a reduced exposure and reported HCV incidence as an outcome in people who inject drugs. We defined interventions as current OST (within previous 6 months), lifetime use of OST and high NSP coverage (regular attendance at an NSP or all injections covered by a new needle/syringe) or low NSP coverage (irregular attendance at an NSP or less than 100% of injections covered by a new needle/syringe) compared with no intervention or reduced exposure.

DATA COLLECTION AND ANALYSIS

We followed the standard Cochrane methodological procedures incorporating new methods for classifying risk of bias for observational studies. We described study methods against the following 'Risk of bias' domains: confounding, selection bias, measurement of interventions, departures from intervention, missing data, measurement of outcomes, selection of reported results; and we assigned a judgment (low, moderate, serious, critical, unclear) for each criterion.

MAIN RESULTS

We identified 28 studies (21 published, 7 unpublished): 13 from North America, 5 from the UK, 4 from continental Europe, 5 from Australia and 1 from China, comprising 1817 incident HCV infections and 8806.95 person-years of follow-up. HCV incidence ranged from 0.09 cases to 42 cases per 100 person-years across the studies. We judged only two studies to be at moderate overall risk of bias, while 17 were at serious risk and 7 were at critical risk; for two unpublished datasets there was insufficient information to assess bias. As none of the intervention effects were generated from RCT evidence, we typically categorised quality as low. We found evidence that current OST reduces the risk of HCV acquisition by 50% (risk ratio (RR) 0.50, 95% confidence interval (CI) 0.40 to 0.63, I2 = 0%, 12 studies across all regions, N = 6361), but the quality of the evidence was low. The intervention effect remained significant in sensitivity analyses that excluded unpublished datasets and papers judged to be at critical risk of bias. We found evidence of differential impact by proportion of female participants in the sample, but not geographical region of study, the main drug used, or history of homelessness or imprisonment among study samples.Overall, we found very low-quality evidence that high NSP coverage did not reduce risk of HCV acquisition (RR 0.79, 95% CI 0.39 to 1.61) with high heterogeneity (I2 = 77%) based on five studies from North America and Europe involving 3530 participants. After stratification by region, high NSP coverage in Europe was associated with a 76% reduction in HCV acquisition risk (RR 0.24, 95% CI 0.09 to 0.62) with less heterogeneity (I2 =0%). We found low-quality evidence of the impact of combined high coverage of NSP and OST, from three studies involving 3241 participants, resulting in a 74% reduction in the risk of HCV acquisition (RR 0.26 95% CI 0.07 to 0.89).

AUTHORS' CONCLUSIONS

OST is associated with a reduction in the risk of HCV acquisition, which is strengthened in studies that assess the combination of OST and NSP. There was greater heterogeneity between studies and weaker evidence for the impact of NSP on HCV acquisition. High NSP coverage was associated with a reduction in the risk of HCV acquisition in studies in Europe.

Assessing the impact and cost-effectiveness of needle and syringe provision and opioid substitution therapy on hepatitis C transmission among people who inject drugs in the UK: an analysis of pooled data sets and economic modelling

Background

There is limited evidence of the impact of needle and syringe programmes (NSPs) and opioid substitution therapy (OST) on hepatitis C virus (HCV) incidence among people who inject drugs (PWID), nor have there been any economic evaluations.

Objective(s)

To measure (1) the impact of NSP and OST, (2) changes in the extent of provision of both interventions, and (3) costs and cost-effectiveness of NSPs on HCV infection transmission.

Design

We conducted (1) a systematic review; (2) an analysis of existing data sets, including collating costs of NSPs; and (3) a dynamic deterministic model to estimate the impact of differing OST/NSP intervention coverage levels for reducing HCV infection prevalence, incidence and disease burden, and incremental cost-effectiveness ratios to measure the cost-effectiveness of current NSP provision versus no provision.

Setting

Cost-effectiveness analysis and impact modelling in three UK sites. The pooled analysis drew on data from the UK and Australia. The review was international.

Participants

PWID.

Interventions

NSP coverage (proportion of injections covered by clean needles) and OST.

Outcome

New cases of HCV infection.

Results

The review suggested that OST reduced the risk of HCV infection acquisition by 50% [rate ratio (RR) 0.50, 95% confidence interval (CI) 0.40 to 0.63]. Weaker evidence was found in areas of high (≥ 100%) NSP coverage (RR 0.77, 95% CI 0.38 to 1.54) internationally. There was moderate evidence for combined high coverage of NSPs and OST (RR 0.29, 95% CI 0.13 to 0.65). The pooled analysis showed that combined high coverage of NSPs and OST reduced the risk of HCV infection acquisition by 29–71% compared with those on minimal harm reduction (no OST, ≤ 100% NSP coverage). NSPs are likely to be cost-effective and are cost-saving in some settings. The impact modelling suggest that removing OST (current coverage 81%) and NSPs (coverage 54%) in one site would increase HCV infection incidence by 329% [95% credible interval (CrI) 110% to 953%] in 2031 and at least double (132% increase; 95% CrI 51% to 306%) the number of new infections over 15 years. Increasing NSP coverage to 80% has the largest impact in the site with the lowest current NSP coverage (35%), resulting in a 27% (95% CrI 7% to 43%) decrease in new infections and 41% (95% CrI 11% to 72%) decrease in incidence by 2031 compared with 2016. Addressing homelessness and reducing the harm associated with the injection of crack cocaine could avert approximately 60% of HCV infections over the next 15 years.

Limitations

Findings are limited by the misclassification of NSP coverage and the simplified intervention definition that fails to capture the integrated services that address other social and health needs as part of this.

Conclusions

There is moderate evidence of the effectiveness of OST and NSPs, especially in combination, on HCV infection acquisition risk. Policies to ensure that NSPs can be accessed alongside OST are needed. NSPs are cost-saving in some sites and cost-effective in others. NSPs and OST are likely to prevent considerable rates of HCV infection in the UK. Increasing NSP coverage will have most impact in settings with low coverage. Scaling up other interventions such as HCV infection treatment are needed to decrease epidemics to low levels in higher prevalence settings.

Future work

To understand the mechanisms through which NSPs and OST achieve their effect and the optimum contexts to support implementation.

Funding

The National Institute for Health Research Public Health Research programme.

Development and validation of a novel scale for measuring interpersonal factors underlying injection drug using behaviours among injecting partnerships

BACKGROUND

People who inject drugs with sexual partners or close friends have high rates of syringe/ancillary equipment sharing and HIV and hepatitis C virus (HCV) infection. Although evidence suggests that interpersonal factors underlie these higher risk profiles, there is no quantitative measure of how interpersonal factors operate within injecting relationships. We aimed to develop and validate a quantitative scale to assess levels of injecting drug-related interpersonal factors associated with risky injecting behaviours within injecting partnerships.

METHODS

We conducted qualitative interviews with 45 people who inject drugs (PWID) who reported having injecting partners to inform item development, and tested these items in a quantitative study of 140 PWID from San Francisco, USA, to assess internal reliability (Cronbach's alpha) and validity (convergent, and discriminant validity).

RESULTS

With results from the qualitative interview data, we developed the Interpersonal Dynamics in Injecting Partnerships (IDIP) scale with 54 final items for 5 subscales of injecting-related interpersonal factors. Exploratory factor analysis revealed 5 factors ("trust", "power", "risk perception", "intimacy", and "cooperation") with eigenvalues of 14.32, 6.18, 3.55, 2.46, and 2.14, explaining 57% of the variance, and indicating good internal reliability (alpha: 0.92-0.68). Strong convergent validity was observed in bivariate logistic regression models where higher levels of trust, intimacy, and cooperation within partnerships were positively associated with partners sharing needles and injecting equipment, whereas higher levels of power and risk perception were negatively associated with partners sharing needles and injecting equipment.

CONCLUSIONS

These findings offer strong evidence that the IDIP scale provides a psychometrically sound measure of injecting drug-related interpersonal dynamics. This measurement tool has the potential to facilitate additional investigations into the individual and collective impact of trust, intimacy, power, cooperation, and risk perception on injection drug using behaviours and engagement in HIV and HCV testing and treatment among PWID in a variety of settings.

Prevalence and predictors of HCV among a cohort of opioid treatment patients in Dar es Salaam, Tanzania

BACKGROUND

The government of Tanzania launched an opioid treatment program (OTP), using methadone, in Dar es Salaam in February of 2011. Hepatitis C virus (HCV) is a leading cause of morbidity and mortality globally, especially among people who inject drugs (PWID). We conducted a cross-sectional study among PWID engaged in OTP in Dar es Salaam to describe the prevalence and predictors of HCV antibody serostatus.

METHODS

Routine programmatic data on patients enrolled in Muhimbili National Hospital's OTP clinic from February 2011 to January 2013 were utilized. Multivariable Poisson regression was used to examine factors associated with HCV antibody serostatus.

RESULTS

A total of 630 PWID enrolled into the OTP clinic during the study period, seven percent of which were women. The overall seroprevalence of HCV antibody was 57% (95% Confidence interval: 53-61%). In adjusted analysis, methadone patients who used heroin for 5-10 years (adjusted prevalence ratio; aPR=1.41; 95% CI: 1.10-1.81) and >10years (aPR=1.48; 95% CI: 1.17-1.88) were more likely to be HCV antibody positive, compared to patients who used heroin for <5years. Patients who reported sharing needles or other equipment at their last injection (aPR=1.20; 95% CI: 1.01-1.41; p=0.022), being arrested (aPR=1.20; 95% CI: 1.04-1.40; p=0.012) and who were HIV-positive (aPR=1.84; 95% CI: 1.56-2.16; p<0.001) were also more likely to be HCV antibody positive than their counterparts.

CONCLUSION

Our observed HCV antibody prevalence among PWID engaged in OTP is higher than previously reported estimates in Dar es Salaam. Predictors of HCV antibody serostatus in this sample were similar to those found among PWID in many other settings. Integrating HCV care and treatment into OTP clinics should be considered, leveraging lessons learned from the integration of HIV services into OTP. Global efforts to develop HCV care and treatment programs in low and middle-income countries are critical, especially among PWID who have a high burden of HCV.

Are the testing needs of key European populations affected by hepatitis B and hepatitis C being addressed? A scoping review of testing studies in Europe

Aim

To investigate whether or not key populations affected by hepatitis B and hepatitis C are being tested sufficiently for these diseases throughout the European region.

Methods

We searched MEDLINE and EMBASE for studies on HBV and HCV testing in the 53 Member States of the World Health Organization European Region following PRISMA criteria.

Results

136 English-language studies from 24 countries published between January 2007 and June 2013 were found. Most studies took place in 6 countries: France, Germany, Italy, the Netherlands, Turkey, and the United Kingdom. 37 studies (27%) addressed HBV, 46 (34%) HCV, and 53 (39%) both diseases. The largest categories of study populations were people who use drugs (18%) and health care patient populations (17%). Far fewer studies focused on migrants, prison inmates, or men who have sex with men.

Conclusions

The overall evidence base on HBV and HCV testing has considerable gaps in terms of the countries and populations represented and validity of testing uptake data. More research is needed throughout Europe to guide efforts to provide testing to certain key populations.

Age- and time-dependent prevalence and incidence of hepatitis C virus infection in drug users in France, 2004-2011: model-based estimation from two national cross-sectional serosurveys

Hepatitis C virus (HCV) infection is a public health issue worldwide. Injecting drug use remains the major mode of transmission in developed countries. Monitoring the HCV transmission dynamic over time is crucial, especially to assess the effect of harm reduction measures in drug users (DU). Our objective was to estimate the prevalence and incidence of HCV infection in DU in France using data from a repeated cross-sectional survey conducted in 2004 and 2011. Age- and time-dependent HCV prevalence was estimated through logistic regression models adjusted for HIV serostatus or injecting practices. HCV incidence was estimated from a mathematical model linking prevalence and incidence. HCV prevalence decreased from 58·2% [95% confidence interval (CI) 49·7-66·8] in 2004 to 43·2% (95% CI 38·8-47·7) in 2011. HCV incidence decreased from 7·9/100 person-years (95% CI 6·4-9·4) in 2004 to 4·4/100 person-years (95% CI 3·3-5·9) in 2011. HCV prevalence and incidence were significantly associated with age, calendar time, HIV serostatus and injecting practices. In 2011, the highest estimated incidence was in active injecting DU (11·2/100 person-years). Given the forthcoming objective of generalizing access to new direct antiviral agents for HCV infection, our results contribute to decision-making and policy development regarding treatment scale-up and disease prevention in the DU population.

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.

Epidemiology of hepatitis C virus infection among people receiving opioid substitution therapy (ECHO): study protocol

BACKGROUND

Hepatitis C virus infection is highly prevalent among people who inject drugs. Opioid substitution therapy, the standard treatment for opioid dependence, provides an excellent opportunity for the treatment of hepatitis C virus infection due to the close and regular contact between patients and clinicians. However, there is little research on the impact of opioid substitution therapy on the prevalence of the hepatitis C virus at a national level. This paper describes the protocol for the Epidemiology of Hepatitis C Virus Infection among People Receiving Opioid Substitution Therapy (ECHO) study. The aim of this study is to estimate the national prevalence and incidence of hepatitis C virus infection among people receiving opioid substitution therapy in Germany and to describe factors associated with hepatitis C treatment uptake and seroconversion.

METHODS/DESIGN

An observational, longitudinal, multicentre study is being conducted between 2014 and 2016 in a representative sample of approximately 2500 people receiving opioid substitution therapy from about 100 clinicians providing opioid substitution therapy in Germany. Data will be collected during routine patient care and by means of patient and clinician questionnaires at baseline and 12-month follow-up. Stratified sampling will be performed to obtain a representative sample of clinicians providing opioid substitution therapy. The strata will be constructed based on the distribution of the total sample of clinicians providing opioid substitution therapy in Germany according to German Federal State and the number of patients per clinician.

DISCUSSION

Opioid substitution therapy may be an important strategy to prevent the spread of hepatitis C virus in opioid dependent populations, but its effectiveness may be diminished by our limited understanding of factors associated with treatment uptake and seroconversion. The present study will provide important information for developing strategies to address hepatitis C virus-related disease burden in people receiving opioid substitution therapy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02395198.

A longitudinal study of hepatitis C virus testing and infection status notification on behaviour change in people who inject drugs

BACKGROUND

Hepatitis C virus (HCV) testing and counselling have the potential to impact individual behaviour and transmission dynamics at the population level. Evidence of the impact of an HCV-positive status notification on injection risk reduction is limited. The objective of our study was to (1) assess drug and alcohol use and injection risk behaviours following notification; (2) to compare behaviour change in people who inject drugs (PWID) who received a positive test result and those who remained negative; and (3) to assess the effect of age on risk behaviour.

METHODS

Data from the International Collaboration of Incident HIV and HCV Infection in Injecting Cohorts (InC3 Study) were analysed. Participants who were initially HCV seronegative were followed prospectively with periodic HCV blood testing and post-test disclosure and interview-administered questionnaires assessing drug use and injection behaviours. Multivariable generalised estimating equations were used to assess behavioural changes over time.

RESULTS

Notification of an HCV-positive test was independently associated with a small increase in alcohol use relative to notification of a negative test. No significant differences in postnotification injection drug use, receptive sharing of ancillary injecting equipment and syringe borrowing postnotification were observed between diagnosis groups. Younger PWID receiving a positive HCV test notification demonstrated a significant increase in subsequent alcohol use compared with younger HCV negative.

CONCLUSIONS

The proportion of PWID reporting alcohol use increased among those receiving an HCV-positive notification, increased the frequency of alcohol use postnotification, while no reduction in injection drug use behaviours was observed between notification groups. These findings underscore the need to develop novel communication strategies during post-test notification to improve their impact on subsequent alcohol use and risk behaviours.

Enhancing the detection and management of acute hepatitis C virus infection

Acute HCV infection refers to the 6-month period following infection acquisition, although this definition is somewhat arbitrary. While spontaneous clearance occurs in approximately 25%, the majority will develop chronic HCV infection with the potential for development of cirrhosis, end stage liver disease and hepatocellular carcinoma. Detection of acute HCV infection has been hampered by its asymptomatic or non-specific presentation, lack of specific diagnostic tests and the inherent difficulties in identifying and following individuals at highest risk of transmitting and acquiring HCV infection, such as people who inject drugs (PWID). However, recognition of those with acute infection may have individual and population level benefits and could represent an ideal opportunity for intervention. Despite demonstration that HCV treatment is feasible and successful in PWID, treatment uptake remains low with multiple barriers to care at an individual and systems level. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment, treatment and prevention in this group are urgently needed. As the therapeutic landscape of chronic HCV management is revolutionised by the advent of simple, highly effective directly-acting antiviral (DAA) therapy, similar opportunities may exist in acute infection. This review will discuss issues surrounding improving the detection and management of acute HCV infection, particularly in PWID.

The undiagnosed chronically-infected HCV population in France. Implications for expanded testing recommendations in 2014

BACKGROUND

Recent HCV therapeutic advances make effective screening crucial for potential HCV eradication. To identify the target population for a possible population-based screening strategy to complement current risk-based testing in France, we aimed to estimate the number of adults with undiagnosed chronic HCV infection and age and gender distribution at two time points: 2004 and 2014.

METHODS

A model taking into account mortality, HCV incidence and diagnosis rates was applied to the 2004 national seroprevalence survey.

RESULTS

In 2014, an estimated 74,102 individuals aged 18 to 80 were undiagnosed for chronic HCV infection (plausible interval: 64,920-83,283) compared with 100,868 [95%CI: 58,534-143,202] in 2004. Men aged 18-59 represented approximately half of the undiagnosed population in 2014. The proportion of undiagnosed individuals in 2004 (43%) varied from 21.9% to 74.1% in the 1945-1965 and 1924-1944 birth cohorts. Consequently, age and gender distributions between the chronically-infected (diagnosed and undiagnosed) and undiagnosed HCV populations were different, the 1945-1965 birth cohort representing 48.9% and 24.7%, respectively.

CONCLUSIONS

Many individuals were still undiagnosed in 2014 despite a marked reduction with respect to 2004. The present work contributed to the 2014 recommendation of a new French complementary screening strategy, consisting in one-time simultaneous HCV, HBV and HIV testing in men aged 18-60. Further studies are needed to assess the cost-effectiveness and feasibility of such a strategy. We also demonstrated that data on the undiagnosed HCV population are crucial to help adapt testing strategies, as the features of the chronically-infected HCV population are very distinct.

The impact of methadone maintenance therapy on hepatitis C incidence among illicit drug users

AIMS

To determine the relationship between methadone maintenance therapy (MMT) and hepatitis C (HCV) seroconversion among illicit drug users.

DESIGN

A generalized estimating equation model assuming a binomial distribution and a logit-link function was used to examine for a possible protective effect of MMT use on HCV incidence.

SETTING

Data from three prospective cohort studies of illicit drug users in Vancouver, Canada between 1996 and 2012.

PARTICIPANTS

A total of 1004 HCV antibody-negative illicit drug users stratified by exposure to MMT.

MEASUREMENTS

Baseline and semi-annual HCV antibody testing and standardized interviewer-administered questionnaire soliciting self-reported data relating to drug use patterns, risk behaviors, detailed socio-demographic data and status of active participation in an MMT program.

FINDINGS

One hundred and eighty-four HCV seroconversions were observed for an HCV incidence density of 6.32 [95% confidence interval (CI) = 5.44-7.31] per 100 person-years. After adjusting for potential confounders, MMT exposure was protective against HCV seroconversion [adjusted odds ratio (AOR) = 0.47; 95% CI = 0.29-0.76]. In subanalyses, a dose-response protective effect of increasing MMT exposure on HCV incidence (AOR = 0.87; 95% CI = 0.78-0.97) per increasing 6-month period exposed to MMT was observed.

CONCLUSION

Participation in methadone maintenance treatment appears to be highly protective against hepatitis C incidence among illicit drug users. There appears to be a dose-response protective effect of increasing methadone exposure on hepatitis C incidence.

Opioid substitution therapy protects against hepatitis C virus acquisition in people who inject drugs: the HITS-c study

OBJECTIVE

To estimate hepatitis C virus (HCV) incidence and identify associated risk and protective factors among people who inject drugs (PWID) in Sydney, New South Wales.

DESIGN, SETTING AND PARTICIPANTS

Community-based prospective observational study of serologically confirmed HCV antibody-negative PWID enrolled in six Sydney neighbourhoods located in three distinct regions between 10 November 2008 and 31 October 2011.

MAIN OUTCOME MEASURES

Serologically confirmed HCV incidence per person-years (py); and self-reported demographic and behavioural risk factors for HCV infection.

RESULTS

The overall incidence of HCV infection was 7.9/100 py. Risk factors independently associated with incident HCV infection were younger age (adjusted hazard ratio [AHR] for age < 27 years, 5.66; 95% CI, 1.69-18.95; P = 0.005) and daily or more frequent injecting (AHR, 4.06; 95% CI, 1.15-14.30; P = 0.03). Opioid substitution therapy (OST) was protective against HCV seroconversion and was associated with a reduced risk of incident infection among those who mainly injected heroin or other opioids (AHR for those not receiving OST while mainly injecting heroin or other opioids, 5.64; 95% CI, 1.30-24.42; P = 0.02).

CONCLUSION

The observed HCV incidence was substantially lower than the incidence of 30.8/100 py observed a decade earlier in a similar NSW-based cohort, suggesting a decline in HCV incidence among PWID. This is likely due to increased coverage of OST, combined with a probable decrease in the population of PWID.

Factors associated with recently acquired hepatitis C virus infection in people who inject drugs in England, Wales and Northern Ireland: new findings from an unlinked anonymous monitoring survey

Monitoring infections and risk in people who inject drugs (PWID) is important for informing public health responses. In 2011, a novel hepatitis C antibody (anti-HCV) avidity-testing algorithm to identify samples compatible with recent primary infection was introduced into a national surveillance survey. PWID are recruited annually, through >60 needle-and-syringe programmes and prescribing services. Of the 980 individuals that could have been at risk of HCV infection, there were 20 (2%) samples that were compatible with recent primary infection. These were more common among: those imprisoned ⩾5 times [8/213; adjusted odds ratio (aOR) 8·7, 95% confidence interval (CI) 2·04-37·03]; women (8/230; aOR 3·8, 95% CI 1·41-10·38); and those ever-infected with hepatitis B (5/56; aOR 6·25, 95% CI 2·12-18·43). This study is the first to apply this algorithm and to examine the risk factors associated with recently acquired HCV infection in a national sample of PWID in the UK. These findings highlight underlying risks and suggest targeted interventions are needed.

Assessing the feasibility of hepatitis C virus vaccine trials: results from the Hepatitis C Incidence and Transmission Study-community (HITS-c) vaccine preparedness study

Efficacy trials of preventive hepatitis C virus (HCV) vaccine candidates raise challenging scientific and ethical issues. Based on data from the first 3 years of a community-based prospective observational study - the Hepatitis C Incidence and Transmission Study-community (HITS-c) - this paper examines the feasibility of conducting trials of candidate HCV vaccines with people who inject drugs (PWID) in Sydney, Australia. Of the 166 PWID confirmed HCV antibody negative and eligible for enrolment, 156 (94%) completed baseline procedures. Retention was high, with 89% of participants retained at 48 weeks and 76% of participants completing at least 75% of study visits within 2 weeks of schedule. The rate of primary HCV infection was 7.9/100 py (95% CI 4.9, 12.7). Of the 17 incident cases, 16 completed at least one follow-up assessment and 12 (75%) had evidence of chronic viraemia with progression to chronic HCV infection estimated to be 6/100 py. Power calculations suggest a chronic HCV infection rate of at least 12/100 py (primary HCV infection rate 16/100 py) will be required for stand-alone trials of highly efficacious candidates designed to prevent chronic infection. However, elevated primary HCV infection was observed among participants not receiving opioid substitution therapy who reported heroin as the main drug injected (26.9/100 py, 95% CI 14.5, 50.0) and those who reported unstable housing (23.5/100 py, 95% CI 7.6, 72.8), daily or more frequent injecting (22.7/100 py, 95% CI 12.2, 42.2) and receptive syringe sharing (23.6/100 py, 95% CI 9.8, 56.7) in the 6 months prior to baseline. These data suggest that it is possible to recruit and retain at-risk PWID who adhere to study protocols and that modification of eligibility criteria may identify populations with sufficiently high HCV incidence. Results support the feasibility of large multi-centre HCV vaccine trials, including in the Australian setting.

Rapid decline in HCV incidence among people who inject drugs associated with national scale-up in coverage of a combination of harm reduction interventions

Background

Government policy has precipitated recent changes in the provision of harm reduction interventions – injecting equipment provision (IEP) and opiate substitution therapy (OST) – for people who inject drugs (PWID) in Scotland. We sought to examine the potential impact of these changes on hepatitis C virus (HCV) transmission among PWID.

Methods and Findings

We used a framework to triangulate different types of evidence: ‘group-level/ecological’ and ‘individual-level’. Evidence was primarily generated from bio-behavioural cross-sectional surveys of PWID, undertaken during 2008-2012. Individuals in the window period (1–2 months) where the virus is present, but antibodies have not yet been formed, were considered to have recent infection. The survey data were supplemented with service data on the provision of injecting equipment and OST. Ecological analyses examined changes in intervention provision, self-reported intervention uptake, self-reported risk behaviour and HCV incidence; individual-level analyses investigated relationships within the pooled survey data. Nearly 8,000 PWID were recruited in the surveys. We observed a decline in HCV incidence, per 100 person-years, from 13.6 (95% CI: 8.1–20.1) in 2008–09 to 7.3 (3.0–12.9) in 2011–12; a period during which increases in the coverage of OST and IEP, and decreases in the frequency of injecting and sharing of injecting equipment, were observed. Individual-level evidence demonstrated that combined high coverage of needles/syringes and OST were associated with reduced risk of recent HCV in analyses that were unweighted (AOR 0.29, 95%CI 0.11–0.74) and weighted for frequency of injecting (AOR_w 0.05, 95%CI 0.01–0.18). We estimate the combination of harm reduction interventions may have averted 1400 new HCV infections during 2008–2012.

Conclusions

This is the first study to demonstrate that impressive reductions in HCV incidence can be achieved among PWID over a relatively short time period through high coverage of a combination of interventions.

Hepatitis C virus infection epidemiology among people who inject drugs in Europe: a systematic review of data for scaling up treatment and prevention

BACKGROUND

People who inject drugs (PWID) are a key population affected by hepatitis C virus (HCV). Treatment options are improving and may enhance prevention; however access for PWID may be poor. The availability in the literature of information on seven main topic areas (incidence, chronicity, genotypes, HIV co-infection, diagnosis and treatment uptake, and burden of disease) to guide HCV treatment and prevention scale-up for PWID in the 27 countries of the European Union is systematically reviewed.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE and Cochrane Library for publications between 1 January 2000 and 31 December 2012, with a search strategy of general keywords regarding viral hepatitis, substance abuse and geographic scope, as well as topic-specific keywords. Additional articles were found through structured email consultations with a large European expert network. Data availability was highly variable and important limitations existed in comparability and representativeness. Nine of 27 countries had data on HCV incidence among PWID, which was often high (2.7-66/100 person-years, median 13, Interquartile range (IQR) 8.7-28). Most common HCV genotypes were G1 and G3; however, G4 may be increasing, while the proportion of traditionally 'difficult to treat' genotypes (G1+G4) showed large variation (median 53, IQR 43-62). Twelve countries reported on HCV chronicity (median 72, IQR 64-81) and 22 on HIV prevalence in HCV-infected PWID (median 3.9%, IQR 0.2-28). Undiagnosed infection, assessed in five countries, was high (median 49%, IQR 38-64), while of those diagnosed, the proportion entering treatment was low (median 9.5%, IQR 3.5-15). Burden of disease, where assessed, was high and will rise in the next decade.

CONCLUSION

Key data on HCV epidemiology, care and disease burden among PWID in Europe are sparse but suggest many undiagnosed infections and poor treatment uptake. Stronger efforts are needed to improve data availability to guide an increase in HCV treatment among PWID.

Higher risk of incident hepatitis C virus among young women who inject drugs compared with young men in association with sexual relationships: a prospective analysis from the UFO Study cohort

BACKGROUND

Female injection drug users (IDUs) may report differences in injection behaviours that put them at greater risk for hepatitis C virus (HCV). Few studies have examined these in association with HCV incidence.

METHODS

Longitudinal data from a cohort of 417 HCV-uninfected IDU aged 30 or younger were analysed. Cox proportional hazards was used to model female sex as a predictor of new HCV infection. General estimating equation (GEE) analysis was used to model female sex as a predictor of HCV-associated risk behaviour prospectively.

RESULTS

Women were significantly more likely than men to become infected with HCV during study follow-up (HR 1.4, p<0.05), and were also more likely than men to report high-risk injecting behaviours, especially in the context of sexual and injecting relationships. Sex differences in injecting behaviours appeared to explain the relationship between sex and HCV infection.

CONCLUSIONS

Young women's riskier injection practices lead to their higher rates of HCV infection. Further study on the impact of intimate partnership on women's risk behaviour is warranted.

The long-term effectiveness of methadone maintenance treatment in prevention of hepatitis C virus among illicit drug users: a modeling study

Background:

Chronic infection with hepatitis C virus (HCV) is increasingly recognized as a major global health problem. Illicit injection drug use is an important risk factor for the rising hepatitis C virus (HCV) prevalence in IR Iran.

Objectives:

The objective of this study was to determine the long-term effectiveness (total quality adjusted life years (QALYs) gained) of methadone maintenance treatment (MMT program) in prevention of HCV infection among injecting drug users (IDUs).

Materials and Methods:

A number of Markov models were developed to model morbidity and mortality among IDUs. The input data used in modeling were collected by a self-reported method from 259 IDUs before registration and one year after MMT and also from previous studies. One way and probabilistic sensitivity analyses were done to show the effects of uncertainty in parameters on number of life years and QALYs saved. The expected consequences were estimated using a life-time time horizon for the two strategies including implementation and not implementation of the MMT program.

Results:

Our model estimated that total number of discounted life years lived per IDU with and without the MMT program would be 5.15 (5.05 - 5.25) and 4.63 (4.42 - 4.81), respectively. The model also estimated that total number of discounted QALYs lived per IDU with and without the MMT program would be 4.11 (3.86 - 4.41) and 2.45 (2.17 - 2.84). Simulation results indicated that all differences in life years and QALYs lived between the two strategies were statistically significant (p < 0.001). Based on our model, total discounted life years and QALYs saved in a cohort of 1000 IDUs were 1790 (1520 - 2090) and 1590 (1090- 2090), respectively.

Conclusions:

Considering the high prevalence of illicit injecting drug use in Iran and MMT effectiveness in prevention of HCV infection, it is necessary to develop MMT centers at regional and national levels.

High rates of hepatitis C virus reinfection and spontaneous clearance of reinfection in people who inject drugs: a prospective cohort study

Hepatitis C virus reinfection and spontaneous clearance of reinfection were examined in a highly characterised cohort of 188 people who inject drugs over a five-year period. Nine confirmed reinfections and 17 possible reinfections were identified (confirmed reinfections were those genetically distinct from the previous infection and possible reinfections were used to define instances where genetic differences between infections could not be assessed due to lack of availability of hepatitis C virus sequence data). The incidence of confirmed reinfection was 28.8 per 100 person-years (PY), 95%CI: 15.0-55.4; the combined incidence of confirmed and possible reinfection was 24.6 per 100 PY (95%CI: 16.8-36.1). The hazard of hepatitis C reinfection was approximately double that of primary hepatitis C infection; it did not reach statistical significance in confirmed reinfections alone (hazard ratio [HR]: 2.45, 95%CI: 0.87-6.86, p=0.089), but did in confirmed and possible hepatitis C reinfections combined (HR: 1.93, 95%CI: 1.01-3.69, p=0.047) and after adjustment for the number of recent injecting partners and duration of injecting. In multivariable analysis, shorter duration of injection (HR: 0.91; 95%CI: 0.83-0.98; p=0.019) and multiple recent injecting partners (HR: 3.12; 95%CI: 1.08-9.00, p=0.035) were independent predictors of possible and confirmed reinfection. Time to spontaneous clearance was shorter in confirmed reinfection (HR: 5.34, 95%CI: 1.67-17.03, p=0.005) and confirmed and possible reinfection (HR: 3.10, 95%CI: 1.10-8.76, p-value=0.033) than primary infection. Nonetheless, 50% of confirmed reinfections and 41% of confirmed or possible reinfections did not spontaneously clear.

Conclusions: Hepatitis C reinfection and spontaneous clearance of hepatitis C reinfection were observed at high rates, suggesting partial acquired natural immunity to hepatitis C virus. Public health campaigns about the risks of hepatitis C reinfection are required.

Hepatitis C avoidance in injection drug users: a typology of possible protective practices

Introduction

Hepatitis C virus (HCV) represents a serious public health concern. People who inject drugs (PWID) are at particular risk and nearly half (45%) of PWID in England may be infected. HCV prevention interventions have only had moderate impact on the prevalence of HCV in this population. Using qualitative methods, we sought to detail the protective practices potentially linked to HCV avoidance among PWID, and explore the motivations for these.

Methods

The study used a life history approach allowing participants to detail their lived experience both before and during the course of their injecting careers. Thirty-seven participants were recruited from drug services in London, and from referrals within local injecting networks. A baseline and follow-up in-depth qualitative interview was carried out with each participant, and for half, a third interview was also undertaken. All underwent testing for HCV antibody. Analyses focused on developing a descriptive typology of protective practices potentially linked to HCV avoidance.

Results

Practices were deemed to be protective against HCV if they could be expected a priori to reduce the number of overall injections and/or the number of injections using shared injecting equipment. Participants reported engaging in various protective practices which fell into three categories identified through thematic analysis: principles about injecting, preparedness, and flexibility.

Conclusions

All participants engaged in protective practices irrespective of serostatus. It is important to consider the relative importance of different motivations framing protective practices in order to formulate harm reduction interventions which appeal to the situated concerns of PWID, especially given that these protective practices may also help protect against HIV and other blood borne infections.

Factors associated with uptake, adherence, and efficacy of hepatitis C treatment in people who inject drugs: a literature review

INTRODUCTION AND METHODS

Hepatitis C virus (HCV) infections are highly prevalent amongst people who inject drugs (PWID). Despite well documented evidence of its effectiveness, suggested cost-effectiveness, and potential to reduce HCV prevalence rates, the uptake of antiviral HCV treatment by PWID is low. This nonsystematic literature review describes factors associated with the uptake, adherence, and efficacy of HCV treatment among PWID and discusses strategies to increase their uptake of treatment.

RESULTS

Low HCV treatment uptake among PWID is associated with a number of patient-related and provider-related barriers. Beliefs and fears about low efficacy and adverse effects on the patient's part are common. A substantial number of factors are associated with the chaotic lifestyle and altered social functioning of PWID, which are often associated with decompensation or relapsing into drug addiction. This may lead to perceived low adherence with treatment and low efficacy on the provider's part too, where lack of support, inadequate management of addiction, and other drug-related problems and poor treatment of side effects have been described. Practical issues such as the accessibility of treatment and finances also play a role. Strategies to improve the HCV treatment rate among PWID involve pretreatment management and assessment, a multidisciplinary approach, management of side effects, and enhanced education and counseling.

CONCLUSION

Specific factors are associated with poorer treatment outcomes in PWID on the side of both the patient and the treatment system. However, given that PWID can achieve treatment adherence and sustained virologic response rates comparable with those in nondrug users, drug use per se should not be considered a criterion for exclusion from treatment. Further development of measures leading to higher uptake of treatment and adherence in PWID and appropriate adaptation of HCV treatment guidelines represent important tools in this regard.