Risk factors for hepatitis C seropositivity among young people who inject drugs in New York City: Implications for prevention

HCV testing and linkage to care for hepatitis C virus infection for marginalized drug user populations attending a harm reduction service in Bologna, Italy

Our aim was to estimate the prevalence of HCV in a highly vulnerable population of substance users living with social difficulties and marginality who came into contact with the mobile harm reduction service in the city of Bologna (Northern Italy). Testing was offered in a van (mobile unit) by using a point-of-care HCV antibody test. For the HCV RNA test, the Xpert HCV Viral Load Fingerstick Test was used. Participants with a detectable HCV RNA were accompanied within two weeks to the Infectious Diseases Department Sant' Orsola Hospital Bologna to start HCV treatment. With regard to the main study findings, 54% reported having never been HCV tested before; a prevalence of HCV RNA of 6% among all participants and 22% among those injecting drugs was found; among the HCV RNA positive participants, 80% were accompanied to treatment. Our study suggests that mobile harm reduction services, in networks with healthcare facilities, are able to offer a continuous HCV screening service and linkage to care for people with drug use living in socially marginalized conditions.

Modeling the impact of the COVID-19 pandemic on achieving HCV elimination amongst young and unstably housed people who inject drugs in San Francisco

BACKGROUND

Young adult (18-30 years) people who inject drugs (PWID) face high hepatitis C virus (HCV) prevalence. In San Francisco, where >60% of PWID lack stable housing, barriers hinder HCV treatment access. We assessed progress towards the World Health Organization's (WHO) HCV elimination goal of an 80% reduction in incidence over 2015-2030, focusing on young (YPWID) and unstably housed PWID in San Francisco.

METHODS

We developed a dynamic HCV transmission model among PWID, parameterized and calibrated using bio-behavioural survey datasets from San Francisco. This included 2018 estimates for the antibody-prevalence among PWID (77%) and care cascade estimates for HCV for YPWID (72% aware of their status and 33% ever initiating treatment). Based on programmatic data, we assumed a 53.8% reduction in testing and 40.7% decrease in treatment from 2020 due to the COVID-19 pandemic, which partially rebounded from April 2021 with testing rates then being 31.1% lower than pre-pandemic rates and treatment numbers being 19.5% lower. We simulated different scenarios of how services changed after the pandemic to project whether elimination goals would be met.

RESULTS

Continuing post-pandemic rates of testing and treatment, the model projects an 83.3% (95% credibility interval [95% CrI]:60.6-96.9%) decrease in incidence among PWID over 2015-2030 to 1.5/100pyrs (95% CrI:0.3-4.4) in 2030. The probability of achieving the elimination goal by 2030 is 62.0%. Among YPWID and unstably housed PWID, the probability of achieving the elimination goal by 2030 is 54.8 and 67.6%, respectively. Importantly, further increasing testing and treatment rates to pre-pandemic levels by 2025 only results in a small increase in the probability (67.5%) of the elimination goal being achieved among all PWID by 2030, while increased coverage of medication for opioid use disorder among YPWID and/or housing interventions results in the probability of achieving elimination increasing to over 75%.

CONCLUSION

The COVID-19 pandemic impeded progress toward achieving HCV elimination. Our findings indicate that existing partial rebounds in HCV testing and treatment may achieve the elimination goal by 2030, with an additional scale-up of interventions aimed at YPWID or unstably housed PWID ensuring San Francisco is likely to achieve elimination by 2030.

Infectious Diseases Among People Experiencing Homelessness: A Systematic Review of the Literature in the United States and Canada, 2003-2022

Homelessness increases the risk of acquiring an infectious disease. We conducted a systematic review of the literature to identify quantitative data related to infectious diseases and homelessness. We searched Google Scholar, PubMed, and SCOPUS for quantitative literature published from January 2003 through December 2022 in English from the United States and Canada. We excluded literature on vaccine-preventable diseases and HIV because these diseases were recently reviewed. Of the 250 articles that met inclusion criteria, more than half were on hepatitis C virus or Mycobacterium tuberculosis. Other articles were on COVID-19, respiratory syncytial virus, Staphylococcus aureus, group A Streptococcus, mpox (formerly monkeypox), 5 sexually transmitted infections, and gastrointestinal or vectorborne pathogens. Most studies showed higher prevalence, incidence, or measures of risk for infectious diseases among people experiencing homelessness as compared with people who are housed or the general population. Although having increased published data that quantify the infectious disease risks of homelessness is encouraging, many pathogens that are known to affect people globally who are not housed have not been evaluated in the United States or Canada. Future studies should focus on additional pathogens and factors leading to a disproportionately high incidence and prevalence of infectious diseases among people experiencing homelessness.

Prevalence and associated risk factors of current hepatitis C infection among U.S. general population and injection drug users aged 20-59 years: NHANES 2009-2018

INTRODUCTION

The people who inject drugs (PWID) are attributed to high-risk groups for transmission of the Hepatitis C virus (HCV). This study assessed the prevalence and associated factors of current HCV infection (CHI) among U.S. general population and PWID of ages between 20 and 59 years old.

METHODS

This study utilized cross-sectional data from the 2009-2018 National Health and Nutrition Examination Survey, conducting separate analyses for the U.S. general population, including PWID and non-PWID, as well as specific analyses focusing solely on PWID. The analytical methods included the estimation of CHI prevalence, Rao-Scott chi-square test to compare CHI-positive and CHI-negative groups, and univariate and multivariable logistic regressions models to evaluate the associated risk factors of CHI.

RESULTS

The prevalence of CHI among general population and PWID were 1% and 19%, respectively. Compared to non-PWID, the odds of CHI were significantly higher among PWID (OR = 32.6, 95% CI = 17.7-60.3) in general population. Among PWID, male vs. female (OR = 2.6, 95% CI = 1.1-5.9), adults aged 40-59 vs. 20-39 years old (OR = 2.9, 95% CI = 1.2-7.3), Non-Hispanic Black vs. White (OR = 4.6, 95% CI = 1.5-13.6), with high school diploma or less educational attainment vs. above college degree (OR = 3.5, 95% CI = 1.4-9.2) showed higher odds of having CHI.

CONCLUSION

The prevalence of CHI was found to be higher among PWID especially those who were male, aged 40-59 years old, Non-Hispanic Black, and had lower educational attainment. Targeted intervention such as screening and awareness program among PWID population is recommended to reduce the burden of new HCV infections in the U.S.

Correlates of overdose among 2711 people who use drugs and live in 7 rural US sites

BACKGROUND

Overdose rates in rural areas have been increasing globally, with large increases in the United States. Few studies, however, have identified correlates of non-fatal overdose among rural people who use drugs (PWUD). The present analysis describes correlates of nonfatal overdose among a large multistate sample of rural PWUD.

METHODS

This is a cross-sectional analysis of data gathered via surveys with PWUD recruited through seven Rural Opioid Initiative (ROI) sites. Descriptive analyses were conducted to assess the prevalence of past 30-day overdose. Generalized estimating equations were used to estimate a series of multivariable models quantifying relationships of select factors to past-month overdose; factors were selected using the Risk Environment Framework.

RESULTS

The multisite sample included 2711 PWUD, 6% of whom reported overdosing in the past 30 days. In the fully adjusted model, houselessness (AOR=2.27, 95%CI[1.48, 3.48]), a positive test result for Hepatitis C infection (AOR=1.73 95%CI[1.18, 2.52]) and heroin/fentanyl use (AOR= 8.58 95%CI [3.01, 24.50]) were associated with an increased risk of reporting past 30-day overdose, while having a high-school education or less was associated with reduced odds of overdose (AOR=0.52, 95% CI[0.37, 0.74]).

CONCLUSION

As in urban areas, houselessness, Hepatitis C infection, and the use of heroin and fentanyl were significant correlates of overdose. Widespread access to overdose prevention interventions - including fentanyl test strips and naloxone - is critical in this rural context, with particular outreach needed to unhoused populations, people living with Hepatitis C, and people using opioids.

Prevalence and associated risk factors of hepatitis C antibody and RNA among people who inject drugs in Puerto Rico

INTRODUCTION

As a public health crisis, hepatitis C viral infection (HCV) is highly prevalent among people who inject drugs (PWID). We aimed to assess factors associated with HCV antibody (Ab) and HCV ribonucleic acid (RNA) positivity among PWID in Puerto Rico.

METHODS

The study recruited a total of 150 persons in rural and peri-urban community settings through the respondent-driven sampling method and administered a structured questionnaire. We conducted HIV and HCV testing using dried blood spots (DBS). We examined correlates of HCV infection with sociodemographics, drug use patterns, and injection practices using regression in bivariate and multivariable analysis.

RESULTS

Of the 150 participants, 89 % were male; 11 % were female; 72 % identified as mixed race; and the median duration of drug injection was 17.8 years. The mean age was 43.1 years, with 64 % of the population being from 23 to 45 years old. Among study participants (n = 150), the prevalence of HCV Ab was 73 %, and HCV RNA was 53 %. Factors significantly associated with HCV Ab and RNA included older age, increasing years of injection, incarceration, injecting other people, and identifying as Black. The belief that syringe air blowing reduces HCV transmission was also independently associated with HCV Ab positivity.

CONCLUSIONS

Our findings regarding risk factors associated with HCV infection show the need to enhance prevention and control strategies for reducing transmission among PWID. Direct-acting antiviral treatment, sustained access to harm reduction, and culturally tailored services will be required to substantially reduce rates of HCV. Community-based treatment models and treatment in correctional settings are needed.

Machine learning for predicting hepatitis B or C virus infection in diabetic patients

Highly prevalent hepatitis B and hepatitis C virus (HBV and HCV) infections have been reported among individuals with diabetes. Given the frequently asymptomatic nature of hepatitis and the challenges associated with screening in some vulnerable populations such as diabetes patients, we conducted an investigation into the performance of various machine learning models for the identification of hepatitis in diabetic patients while also evaluating the significance of features. Analyzing NHANES data from 2013 to 2018, machine learning models were evaluated; random forest (RF), support vector machine (SVM), eXtreme Gradient Boosting (XGBoost), and least absolute shrinkage and selection operator (LASSO) along with stacked ensemble model. We performed hyperparameter tuning to improve the performance of the model, and selected important predictors using the best performance model. LASSO showed the highest predictive performance (AUC-ROC = 0.810) rather than other models. Illicit drug use, poverty, and race were highly ranked as predictive factors for developing hepatitis in diabetes patients. Our study demonstrated that a machine-learning-based model performed optimally in the detection of hepatitis among diabetes patients, achieving high performance. Furthermore, models and predictors evaluated from the current study, we expect, could be supportive information for developing screening or treatment methods for hepatitis care in diabetes patients.

Hepatitis C Cascades: Data to Inform Hepatitis C Elimination in the United States

The United States has a goal to eliminate hepatitis C as a public health threat by 2030. To accomplish this goal, hepatitis C virus (HCV) care cascades (hereinafter, HCV cascades) can be used to measure progress toward HCV elimination and identify disparities in HCV testing and care. In this topical review of HCV cascades, we describe common definitions of cascade steps, review the application of HCV cascades in health care and public health settings, and discuss the strengths and limitations of data sources used. We use examples from the Massachusetts Department of Public Health as a case study to illustrate how multiple data sources can be leveraged to produce HCV cascades for public health purposes. HCV cascades in health care settings provide actionable data to improve health care quality and delivery of services in a single health system. In public health settings at jurisdictional and national levels, HCV cascades describe HCV diagnosis and treatment for populations, which can be challenging in the absence of a single data source containing complete, comprehensive, and timely data representing all steps of a cascade. Use of multiple data sources and strategies to improve interoperability of health care and public health data systems can advance the use of HCV cascades and speed progress toward HCV elimination.

Prevalence of injecting drug use and HIV, hepatitis B, and hepatitis C in people who inject drugs in the Eastern Mediterranean region: a systematic review and meta-analysis

BACKGROUND

Considerable disease burden is attributed to injecting drug use (IDU). This regional systematic review and meta-analysis aimed to assess the prevalence of IDU and the characteristics of people who inject drugs in the 22 countries of the WHO Eastern Mediterranean region.

METHODS

We conducted a systematic review and meta-analysis on the prevalence of IDU, estimation of the population size of people who inject drugs, the characteristics of people who inject drugs, commonly injected drugs, the prevalence of HIV, hepatitis C virus, and hepatitis B virus in people who inject drugs, and opioid agonist treatment and needle and syringe programme services. We searched PubMed, Web of Science, Scopus, Embase, and the Index Medicus for the Eastern Mediterranean Region for documents published between Jan 1, 2010, and April 17, 2022, with no language restrictions. We also searched government reports, civil society information, and UN websites and databases for grey literature published between Jan 1, 2010, and April 17, 2022. Documents were eligible if they reported or estimated an indicator of interest, or reported enough data to permit calculation of the indicator. We extracted data from the eligible documents and calculated national and regional estimates.

FINDINGS

We identified 38 283 documents and included 201 documents in the systematic review. A total of 115 documents were included for the four outcomes for which meta-analyses were performed. The number of people who inject drugs was estimated as 864 597 (95% CI 641 909-1 205 255), amounting to a prevalence of 20·0 per 10 000 adults (95% CI 14·9-27·9) in the region. Among people who inject drugs, the prevalence of HIV was estimated as 19·22% (95% CI 12·86-26·36), hepatitis C virus as 44·82% (29·32-61·16), and hepatitis B virus as 2·66% (0·84-7·26). Countries varied greatly regarding the variables of interest and the availability of relevant data. Nine countries provided needle and syringe programme services and seven countries provided opioid agonist treatment services, mostly with very low, low, or unclear coverage.

INTERPRETATION

The prevalence of IDU in the Eastern Mediterranean region is lower than the global mean, particularly among women. The HIV infection rate is higher than the global mean, and the hepatitis C virus infection rate is lower than the global mean. Harm-reduction services are underdeveloped. Data collection on IDU and provision of services need improvement in the region.

FUNDING

World Health Organization.

TRANSLATIONS

For the Arabic, Farsi and French translations of the abstract see Supplementary Materials section.

Hepatitis Risk in Diabetes Compared to Non-Diabetes and Relevant Factors: A Cross-Sectional Study with National Health and Nutrition Examination Survey (NHANES), 2013-2018

This study aimed to identify the development of hepatitis B or C infection in diabetes patients compared to those without and to elucidate factors associated with the prevalence of hepatitis B or C infection in diabetes. We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) 2013-2018. As evaluation factors, we included variables such as age, race, illicit drug use, and poverty. The diabetic group had a significantly higher prevalence of hepatitis B or C infection than the non-diabetic group (odds ratio (OR) = 1.73; 95% confidence interval (CI), 1.36-2.21, p < 0.01). In multivariate Cox regression, non-poverty and non-illicit drug use were lower risk factors contributing to hepatitis development in diabetes (hazard ratio (HR) = 0.50; 95% CI, 0.32-0.79, p < 0.01, and HR = 0.05; 95% CI, 0.03-0.08, p < 0.01, respectively). Logistic regression also showed that these factors were significant contributors to hepatitis development in the diabetic group (p < 0.01). In patients with diabetes, the development of hepatitis was higher than that in those without, and hepatitis development was influenced by poverty and illicit drug use. This may provide supporting evidence of response strategies for diabetes to care for hepatitis development in advance.

Factors associated with sharing equipment among people who inject drugs: The role of community attachment in harm reduction and health promotion

INTRODUCTION

Sharing injecting equipment is a major route of transmission for blood borne viruses such as hepatitis C and HIV. Although needle and syringe programs are widely available throughout metropolitan Australia, rates of sharing equipment have not significantly changed in recent years. This study aimed to identify factors associated with recent equipment sharing among people who inject drugs in Australia.

METHODS

A paper-based survey was distributed via peer-based organisations between June and November 2018 and was completed by 603 participants. Survey questions addressed recent injecting experiences, equipment sharing, community attachment, stigma and wellbeing. Participants who had recently shared injecting equipment were compared with those who had not shared any equipment using multivariable logistic regression.

RESULTS

Recent equipment sharing was associated with recent heroin use, experiencing any past-year stigma related to injecting drug use, and higher levels of attachment to a community of people who inject drugs. An interaction effect showed increased community attachment was associated with increased odds of sharing equipment among young participants, but with decreased odds of sharing equipment among older participants.

DISCUSSION AND CONCLUSIONS

Community networks of people who inject drugs can play important roles in harm reduction initiatives. While being connected with a community of people who inject drugs increased the odds of sharing injecting equipment, this community connection also increases opportunities for social support, sharing information and mitigating the negative effects of stigma. Collaboratively and meaningfully engaging with communities of people who inject drugs has the potential to increase the reach and effectiveness of health promotion services.

Epidemiology of injecting drug use, prevalence of injecting-related harm, and exposure to behavioural and environmental risks among people who inject drugs: a systematic review

BACKGROUND

People who inject drugs are exposed to various and changing risk environments and are at risk of multiple harms related to injecting drug use (IDU). We aimed to undertake a global systematic review of the prevalence of IDU, key IDU-related harms (including HIV, hepatitis C virus [HCV], and hepatitis B virus [HBV] infection and overdose), and key sociodemographic characteristics and risk exposures for people who inject drugs.

METHODS

We systematically searched for data published between Jan 1, 2017, and March 31, 2022, in databases of peer-reviewed literature (MEDLINE, Embase, and PsycINFO) and grey literature as well as various agency or organisational websites, and disseminated data requests to international experts and agencies. We searched for data on the prevalence, characteristics, and risks of people who inject drugs, including gender, age, sexuality, drug-use patterns, HIV, HCV, and HBV infections, non-fatal overdose, depression, anxiety, and injecting-related disease. Additional data were extracted from studies identified in our previous review. Meta-analyses were used to pool the data where multiple estimates were available for a country. We present country, regional, and global estimates for each variable examined.

FINDINGS

We screened 40 427 reports published between 2017 and 2022, and the 871 eligible reports identified were added to the 1147 documents from the previous review. Evidence of IDU was documented in 190 of 207 countries and territories, and 14·8 million people (95% uncertainty interval [UI] 10·0-21·7) aged 15-64 years globally were estimated to inject drugs. Existing evidence suggests that there might be 2·8 million (95% UI 2·4-3·2) women and 12·1 million (95% UI 11·0-13·3) men who inject drugs globally, and that 0·4% (95% CI 0·3-1·3) of people who inject drugs identify as transgender. The amount of available data on key health and social risks among people who inject drugs varied widely across countries and regions. We estimated that 24·8% (95% CI 19·5-31·6) of people who inject drugs globally had experienced recent homelessness or unstable housing, 58·4% (95% CI 52·0-64·8) had a lifetime history of incarceration, and 14·9% (95% CI 8·1-24·3) had recently engaged in sex work, with substantial geographical variation. Injecting and sexual risk behaviour varied considerably geographically, as did risks of harms. Globally, we estimated that 15·2% (95% CI 10·3-20·9) of people who inject drugs are living with HIV, 38·8% (95% CI 31·4-46·9) have current HCV infection, 18·5% (95% CI 13·9-24·1) have recently overdosed, and 31·7% (95% CI 23·6-40·5) have had a recent skin or soft tissue infection.

INTERPRETATION

IDU is being identified in a growing number of countries and territories that comprise more than 99% of the global population. IDU-related health harms are common, and people who inject drugs continue to be exposed to multiple adverse risk environments. However, quantification of many of these exposure and harms is inadequate and must be improved to allow for better targeting of harm-reduction interventions for these risks.

FUNDING

Australian National Health and Medical Research Council.

Trends and distinct profiles of persons who inject drugs in the United States, 2015-2019

Drug injection represents a major health problem in the US, with severe health consequences including the transmission of blood-borne infections. An examination of the most recent trends in drug injection is warranted by the fast-evolving drug epidemic and recent policy changes such as the federal funding ban on needle exchange programs. This research examines current drug injection trends, patterns, and socioeconomic and behavioral profiles of people who inject drugs (PWID). Data were derived from the 2002 to 2019 National Survey on Drug Use and Health (NSDUH). After examining the annual prevalence of drug injection since 2002, a latent class analysis was conducted to identify drug injection and other substance misuse patterns among PWID using the latest (2015-2019) NSDUH datasets. Associations between class membership and behavioral health comorbidities and treatment receipt were also assessed. The drug injection prevalence among US adults aged 18-64 increased from 0.21% in 2002/2004 to 0.36% in 2017/2019. Three distinctive groups were identified: the heroin injection group (45.2%), the methamphetamine injection group (28.0%), and the multi-drug injection group (26.8%). The methamphetamine injection group reported greater risks of experiencing serious psychological distress, suicidality, and limited substance use treatment. Special attention is needed for those who primarily injected methamphetamine. Programs to promote harm reduction and increase access to addiction treatment need to be expanded in at-risk communities while accounting for their distinct socioeconomic and drug use/misuse profiles.

Factors Associated With Severe Bacterial Infections in People Who Inject Drugs: A Single-center Observational Study

BACKGROUND

People who inject drugs are at increased risk for several bacterial infections such as bacteremia, endocarditis, and osteomyelitis resulting in severe morbidity and high care costs. Limited data exist surrounding the injection drug use practices and behaviors that may increase the risk of these infections.

METHODS

Individuals admitted to a single hospital in New York City with severe bacterial infection, between August 2020 and June 2021, were recruited to partake in an in-depth survey examining potential factors, both demographic and injection drug use behavioral, associated with severe bacterial infections.

RESULTS

Thirty-four participants were recruited with injection drug use-associated severe bacterial infection. The mean age was 36.5 years; 21 (62%) were currently homeless, with 19 (56%) patients admitted for infective endocarditis. The mean length of hospital stay of all participants was 32.2 days; 94% received medication for opioid use disorder while admitted, whereas 35% left before treatment completion with a patient-directed discharge or elopement. Eight-two percent of participants were injected daily in the prior 30 days, with an average of 276 injections per participant. Fifty percent of participants reported requiring multiple sticks per injection event "always" or "very often," with 94% reporting reuse of syringes in the prior month.

CONCLUSIONS

Severe bacterial infections in people who inject drugs resulted in prolonged and complex hospitalization that culminate in suboptimal outcomes despite aggressive measures to engage patients in medication for opioid use disorder. Numerous nonsterile injection drug use practices were identified, indicating a gap in current infection prevention harm reduction messaging.

Investigating the sociodemographic and behavioural factors associated with hepatitis C virus testing amongst people who inject drugs in England, Wales and Northern Ireland: A quantitative cross-sectional analysis

BACKGROUND

Hepatitis C virus (HCV) transmission in the UK is driven by injecting drug use. We explore HCV testing uptake amongst people who inject drugs (PWID) in England, Wales and Northern Ireland, and identify factors associated with i) ever having an HCV test amongst people who have ever injected drugs, and ii) recently having an HCV test (within the current or previous year) amongst people who currently inject drugs (reported injecting drugs within the last year).

METHODS

We analysed data from the 2019 'Unlinked Anonymous Monitoring Survey' of PWID, using logistic regression.

RESULTS

Of 3,127 PWID, 2,065 reported injecting drugs within the last year. Most (86.7%) PWID had a lifetime history of HCV testing. In multivariable analysis, higher odds of ever testing were associated with: female sex (aOR=1.54; 95%CI 1.11-2.14), injecting duration ≥3 years (aOR=2.94; 95%CI 2.13-4.05), ever receiving used needles/syringes (aOR=1.74; 95%CI 1.29-2.36), ever being on opioid agonist treatment (aOR=2.91; 95%CI 2.01-4.21), ever being imprisoned (aOR=1.86; 95%CI 1.40-2.48) and ever being homeless (aOR=1.54; 95%CI 1.14-2.07). Amongst PWID who had injected drugs within the last year, 49.9% had recently undertaken an HCV test. After adjustment, factors associated with higher odds of undertaking a recent HCV test included: injecting crack in the last year (aOR=1.29; 95%CI 1.03-1.61), experiencing a non-fatal overdose in the last year (aOR=1.39; 95%CI 1.05-1.85), ever being on opioid agonist treatment (aOR=1.48; 95%CI 0.97-2.25), receiving HCV information in the last year (aOR=1.99; 95%CI 1.49-2.65) and using a healthcare service in the last year (aOR=1.80; 95%CI 1.21-2.67).

CONCLUSION

Results suggest that PWID who have experienced homelessness and incarceration - amongst the most vulnerable and marginalised in the PWID population - are engaging with HCV testing, but overall there remain missed testing opportunities. Recent initiates to injecting have highest HCV infection risk but lower odds of testing, and peer-education may help target this group.

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.

Hepatitis C antibody prevalence, correlates and barriers to care among people who inject drugs in Central California

Hepatitis C (HCV) infection among people who inject drugs (PWID) is a major public health concern. We examined correlates of HCV antibody (anti-HCV) seropositivity and characteristics of prior HCV testing and treatment among PWID in Fresno, California, which has among the highest prevalence of injection drug use (IDU) in the United States. We surveyed 494 peer-recruited PWID (≥18 years of age) in 2016 about their experiences with HCV testing and treatment, and conducted HCV and HIV antibody testing for all participants. Bivariate analyses and multivariable logistic regressions were used to identify correlates of anti-HCV seropositivity. A majority (65%) tested positive for anti-HCV, with 32% of those being unaware of their HCV status. Anti-HCV seroprevalence was independently and positively associated with older age (AOR = 1.11 per year, 95% CI = 1.06, 1.17), years injecting (AOR = 1.08 per year, 95% CI = 1.03, 1.13), distributive syringe sharing (AOR = 2.76, 95% CI = 1.29, 5.94), having syringes confiscated by police (AOR = 2.65, 95% CI = 1.22, 5.74), ever trading sex (AOR = 3.51, 95% CI = 1.40, 8.81) and negatively associated with being Black/African American (non-Hispanic) (AOR = 0.06, 95% CI = 0.01, 0.47). Prior HCV testing was associated with older age, ever getting syringes from a syringe services program, and having interactions with police. For those aware of their anti-HCV seropositivity, only 11% had initiated treatment; reasons for not seeing a physician regarding diagnosis included not feeling sick (23%), currently using drugs/alcohol (19%) and not knowing where to go for HCV medical care (19%). Our findings highlight the importance of expanding community-based access to sterile syringes alongside HCV testing and treatment services, particularly at syringe service programs where PWID may be more comfortable seeking testing and treatment.

Can Telemedicine Optimize the HCV Care Cascade in People Who Use Drugs? Features of an Innovative Decentralization Model and Comparison with Other Micro-Elimination Strategies

People who use drugs (PWUDs) are a crucial population in the global fight against viral hepatitis. The difficulties in linkage to care, the low adherence to therapy, the frequent loss to follow-up and the high risk of re-infection make the eradication process of the hepatitis C virus (HCV) really hard in this viral reservoir. Several management and treatment models have been tested with the aim of optimizing the HCV care cascade in PWUDs. Models of decentralization of the care process and integration of services seem to provide the highest success rates. Giving this, telemedicine could favor the decentralization of diagnostic-therapeutic management, key for the implementation of linkage to care, reduction of waiting times, optimization of adherence and results and reduction of the costs. The purpose of this literature review is to examine the role and possible impact of telemedicine in optimizing the HCV care cascade, comparing the different care models that have shown to improve the linkage to care and therapeutic adherence in this special population.

Severe bacterial infections in people who inject drugs: the role of injection-related tissue damage

Background

In the context of the current U.S. injection drug use epidemic, targeted public health harm reduction strategies have traditionally focused on overdose prevention and reducing transmission of blood-borne viral infections. Severe bacterial infections (SBI) associated with intravenous drug use have been increasing in frequency in the U.S. over the last decade. This qualitative study aims to identify the risk factors associated with SBI in hospitalized individuals with recent injection drug use.

Methods

Qualitative analysis (n = 15) was performed using an in-depth, semi-structured interview of participants admitted to Bellevue Hospital, NYC, with SBI and recent history of injection drug use. Participants were identified through a referral from either the Infectious Diseases or Addition Medicine consultative services. Interviews were transcribed, descriptively coded, and analyzed for key themes.

Results

Participants reported a basic understanding of prevention of blood-borne viral transmission but limited understanding of SBI risk. Participants described engagement in high risk injection behaviors prior to hospitalization with SBI. These practices included polysubstance use, repetitive tissue damage, nonsterile drug diluting water and multipurpose use of water container, lack of hand and skin hygiene, re-use of injection equipment, network sharing, and structural factors leading to an unstable drug injection environment. Qualitative analysis led to the proposal of an Ecosocial understanding of SBI risk, detailing the multi-level interplay between individuals and their social and physical environments in producing risk for negative health outcomes.

Conclusions

Structural factors and injection drug use networks directly impact drug use, injection drug use practices, and harm reduction knowledge, ultimately resulting in tissue damage and inoculation of bacteria into the host and subsequent development of SBI. Effective healthcare and community prevention efforts targeted toward reducing risk of bacterial infections could prevent long-term hospitalizations, decrease health care expenditures, and reduce morbidity and mortality.

Characteristics associated with HIV and hepatitis C seroprevalence among sexual and injecting partners of HIV positive persons who inject drugs in Nairobi and coastal Kenya

Background

Persons who inject drugs (PWID) have higher HIV and hepatitis C virus (HCV) seroprevalence than the general population in many parts of sub-Saharan Africa (SSA). The seroprevalences of HIV and HCV are also higher in coastal Kenya than in Nairobi. Understanding drivers of regional HIV and HCV variation among PWID in Kenya may inform population-specific prevention interventions.

Methods

Using a cross-sectional study, we defined HIV and HCV seroprevalence among persons identified as sexual or injecting partners of HIV positive PWID in two regions of Kenya and used logistic regression to identify demographic and behavioral characteristics associated with higher seroprevalence.

Results

Among 2386 partners, 469 (19.7%) tested HIV positive and 297(12.4%) tested HCV antibody positive. Partners on the Coast were more likely to live with HIV (seroprevalences: Coast = 23.8%, Nairobi = 17.1%; p < 0.001) and be HCV antibody positive (seroprevalences: Coast = 17.0%, Nairobi = 8.6%; p < 0.001). After adjusting for sex, age, and years injecting and accounting for clustering by site, the higher prevalence of both diseases in the Coast remained significant for HIV (OR 1.68, 95% CI 1.13–2.51) but not for HCV (OR 1.72, 95% CI 0.84–3.74). Compared to those recruited in Nairobi, partners on the Coast were older (Coast = 35 years, Nairobi = 31 years; p < 0.001), more likely to be male (Coast = 77.6%, Nairobi = 61.7%; p < 0.001), to have paid (Coast = 59.2%, Nairobi = 32.8%; p < 0.001) or received (Coast = 44.2%, Nairobi 35.4%; p < 0.001) money for sex, or to have had sex with someone they knew to be HIV positive (Coast 22.0%, Nairobi 10.8%; p < 0.001). Partners who had injected for five or more years had 1.48 times greater odds (95% CI 1.20–1.82) of living with HIV compared to partners who injected less than 5 years and more than twice the odds of HCV (95% CI 1.84–4.11).

Conclusion

HIV and HCV seroprevalence among sexual and injecting partners of PWID was, respectively, 5 times and > 12 times greater than is reported among the general population in Kenya (4% and < 1%, respectively). Providing resources and education will be crucial to reduce exposure and to maintain the lower needle and equipment sharing that we observed compared to other studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07036-8.

Drug use-related stigma, safer injection norms, and hepatitis C infection among a network-based sample of young people who inject drugs

BACKGROUND

Identifying risk for hepatitis C (HCV) infection is important for understanding recent increases in HCV incidence among young people who inject drugs (PWID) in suburban and rural areas; and for refining the targeting of effective HCV preventive interventions. Much of the extant research has focused on individual health behaviors (e.g., risky drug injection behaviors) as predictors of HCV infection. The present study examines two social factors (substance use-related stigma and injection-related social norms), and the interaction between these factors, as predictors of HCV infection.

METHODS

Baseline data were used from an ongoing longitudinal study of young PWID (N = 279; mean age = 30.4 years) from the Chicago suburbs and their injection risk network members. Adjusted logistic regression models were used to examine relationships among substance use-related stigma, safer injection norms, and HCV infection.

RESULTS

Despite a marginal bivariate association between less safe injection norms and HCV infection (OR = 0.74; 95 % CI[0.39, 1.02]; p = .071), a significant stigma X norms interaction (AOR = 0.68; 95 % CI[0.51, 0.90]) suggested that at high levels of stigma, probability of HCV infection was high regardless of injection norms.

CONCLUSIONS

Findings suggest that social factors - specifically, substance use-related stigma and injection norms - are important predictors of HCV infection risk. The interaction found between these social factors suggests that intervening only to change injection norms or behaviors is likely insufficient to reduce risk for HCV infection in high-stigma settings or among high-stigma populations. Future research should develop and evaluate stigma-reduction interventions in combination with safer-injection interventions in order to maximize HCV risk reduction.

Hepatitis C testing and treatment uptake among young people who use opioids in New York City: A cross-sectional study

Young people who use drugs have a rising hepatitis C (HCV) incidence in the United States, but they may face barriers to testing and treatment adoption due to stigma. We conducted a cross-sectional study of New York City residents aged 18-29 years who reported non-medical prescription opioid and/or heroin use in the past 30 days. Participants were recruited from the community between 2014-2016 via respondent-driven sampling. Participants completed an in-person structured survey that included questions about HCV testing and treatment and received HCV antibody testing. There were 539 respondents: 353 people who inject drugs (PWID) and 186 non-PWID. For PWID, median age was 25 years, 65% were male and 73% non-Hispanic White. For non-PWID, median age was 23 years, 73% were male and 39% non-Hispanic White. 20% of PWID and 54% of non-PWID had never been tested for HCV (P < .001). Years since first injection (aOR 1.16, CI: 1.02-1.32, P = .02) and history of substance use treatment (aOR 3.17, CI: 1.53-6.61, P = .02) were associated with prior testing among PWID. The seroprevalence of HCV among PWID was 25%, adjusted for sampling weights. Of the 75 who were aware of their HCV-positive status, 53% had received HCV-related medical care, and 28% had initiated treatment. HCV prevalence among young PWID is high, and many have never been tested. Injection experience and treatment engagement is associated with testing. Interventions to increase testing earlier in injection careers, and to improve linkage to HCV treatment, will be critical for young PWID.

Hepatitis C Virus Prevalence and Incidence in a Large Nationwide Sample of Patients in Opioid Substitution Treatment in Germany: A Prospective Cohort Study

BACKGROUND

Hepatitis C virus (HCV) infection is highly prevalent among people who inject drugs (PWID). Accurate data on HCV prevalence and incidence rates among patients receiving opioid substitution treatment (OST) are needed to estimate the current and future burden of HCV infections in this high-risk population.

METHODS

Baseline data from routine care were collected between October 2014 and June 2016 from randomly selected OST facilities in Germany. The primary outcome measure was the HCV status (antibody and RNA prevalence). Patients who were HCV antibody-negative at baseline were followed up after 12 months to calculate the HCV incidence rate.

RESULTS

Sixty-three facilities from 14 German Federal States provided clinical data for a total of 2466 OST patients. HCV antibody and HCV RNA prevalence were 58.8% (95% confidence interval [CI], 56.8%-60.8%) and 27.3% (95% CI, 25.5%-29.2%), respectively. At baseline, a total of 528 patients (21.4%) had previously undergone antiviral treatment. Moreover, lower HCV RNA prevalence was associated with female gender, employment, younger age, and shorter duration of OST and opioid dependence. The HCV incidence rate was 2.5 cases per 100 person-years.

CONCLUSIONS

The low HCV RNA prevalence and HCV incidence rates confirm that OST in Germany is an effective setting both for treating chronic HCV infections and for preventing new infections among PWID. Scaling up the provision of OST, HCV testing, and HCV treatment among OST patients are important public health strategies for reducing HCV infections in this high-risk population.

HCV and HIV co-infection among people who inject drugs in Vietnam

INTRODUCTION

HIV/HCV co-infection in people who inject drugs (PWID) continues to be a major challenge for health care systems and the PWID themselves. PWID have driven the HIV epidemic in Vietnam but information on HIV/HCV co-infection is limited.

METHODS

A cross-sectional study was conducted with 509 PWID recruited in Hanoi from February 2016 to April 2017. Four mutually exclusive groups were defined based on the presence of detectable HCV RNA and positive HIV confirmation. Multiple logistic regression analyses were performed to explore life-time risk behaviors of HCV mono-infection and HIV/HCV co-infection.

RESULTS

The overall prevalence of HIV and HCV infection was 51.08% and 61.69%, respectively. The prevalence of HCV mono-infection and HIV/HCV co-infection was 22.59% and 39.1%, respectively. We found that engaging in methadone maintenance treatment (MMT) was positively associated with HCV mono-infection (aOR = 2.38, 95% Confidential Interval [CI] 1.07 to 5.28) and with at least either HIV or HCV infection (aOR = 2.22, 95% CI 1.08 to 4.56). Ever being incarcerated was significantly associated with HCV mono-infection (aOR = 2.56, 95% CI 1.33 to 4.90) and HIV/HCV co-infection (aOR = 1.90, 95% CI 1.04 to 3.46). Those who had ever shared with and reused syringes/needles were more likely to have HIV/HCV co-infection (aORs = 5.17 and 2.86, P < 0001, respectively) and have either HIV or HCV infection (aORs = 3.42 and 2.37, P < 0001, respectively).

CONCLUSION

Correlates for HCV mono-infection and HIV/HCV co-infection highlight the need to address risk behaviors, expand MMT programs, and establish HCV sentinel surveillance. The high prevalence of HCV and/or HIV co-infection shows a need for access to HCV treatment.

Evolving trends in the prevalence of hepatitis C virus antibody positivity among HIV-infected men in a community-based primary care setting

Hepatitis C virus (HCV) infections in the United States occurred mostly among those born between 1945 and 1965. However, new infections continue to increase in recent years. To understand the changes in the prevalence and risk factors of HCV infection in different age and risk groups among men living with HIV, we performed a retrospective cross-sectional analyses of 1948 HIV-infected men at a multisite community health centre in urban/suburban and rural Maryland from 2003 through 2014. We used multivariate logistic regression to determine factors associated with HCV antibody (anti-HCV) positivity and restricted cubic spline method to model trends in anti-HCV prevalence over time. The overall anti-HCV prevalence was 24.2%. The annual prevalence declined in the full cohort, from 38% in 2003 to 24% in 2014, and among those ≥ 40 years old. However, the annual prevalence increased initially and then stabilized in the groups of men who were younger (<40 years old) or had injection-drug use and/or sex with men. Among the younger injection-drug users, the prevalence rose from 33% in 2003 to 79% in 2009 and then stabilized. The independent predictors for anti-HCV positivity differed between the men with and without injection-drug use and between those < 40 and ≥ 40 years old. Notably, a high prevalence of anti-HCV was observed among the younger, white injection-drug users residing in rural areas. Thus, the HCV epidemic continued unabated among high-risk individuals in this diverse population of HIV-infected men. The ongoing HCV transmission among young HIV-infected men poses a challenge en route to HCV eradication.

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.

Recommendations for Implementing Hepatitis C Virus Care in Homeless Shelters: The Stakeholder Perspective

Compared with the general population, homeless individuals are at higher risk of hepatitis C infection (HCV) and may face unique barriers in receipt of HCV care. This study sought the perspectives of key stakeholders toward establishing a universal HCV screening, testing, and treatment protocol for individuals accessing homeless shelters. Four focus groups were conducted with homeless shelter staff, practice providers, and social service outreach workers (n = 27) in San Francisco, California, and Minneapolis, Minnesota. Focus groups evaluated key societal, system, and individual-level facilitators and barriers to HCV testing and management. Interviews were transcribed and analyzed thematically. The societal-level barriers identified were lack of insurance, high-out-of-pocket expenses, restriction of access to HCV treatment due to active drug and/or alcohol use, and excessive paperwork required for HCV treatment authorization from payers. System-level barriers included workforce constraints and limited health care infrastructure, HCV stigma, low knowledge of HCV treatment, and existing shelter policies. At the individual level, client barriers included competing priorities, behavioral health concerns, and health attitudes. Facilitators at the system level for HCV care service integration in the shelter setting included high acceptability and buy in, and linkage with social service providers. Conclusion: Despite societal, system, and individual-level barriers identified with respect to the scale-up of HCV services in homeless shelters, there was broad support from key stakeholders for increasing capacity for the provision of HCV services in shelter settings. Recommendations for the scale-up of HCV services in homeless shelter settings are discussed.

A systematic review and meta-analysis of the prevalence of hepatitis C virus infection in people who inject drugs in Iran

BACKGROUND

Hepatitis C virus (HCV) infection is one of the major public health challenges generating a relevant burden. High-risk groups, including people who inject drugs (PWID), are at serious risk for developing HCV. In recent years, several investigations have been conducted in Iran to assess the prevalence e of HCV among PWID. The aim of the present study was to synthesize the literature performing a comprehensive search and meta-analysis.

METHODS

A comprehensive literature search was carried out from January 2000 to September 2019. Several international databases, namely Scopus, PubMed/MEDLINE, Embase, ISI/Web of Science, PsycINFO, CINAHL, the Cochrane Library and the Directory of Open Access Journals (DOAJ), as well as Iranian databases (Barakathns, SID and MagIran), were consulted. Eligible studies were identified according to the following PECOS (population, exposure, comparison/comparator, outcome and study type) criteria: i) population: Iranian population; ii) exposure: injection drug users; iii) comparison/comparator: type of substance injected and level of substance use, iv) outcome: HCV prevalence; and v) study type: cross-sectional study. After finding potentially related studies, authors extracted relevant data and information based on an ad hoc Excel spreadsheet. Extracted data included the surname of the first author, the study journal, the year of publication, the number of participants examined, the type of diagnostic test performed, the number of positive HCV patients, the number of participants stratified by gender, the reported prevalence, the duration of drug injection practice and the history of using a shared syringe.

RESULTS

Forty-two studies were included. 15,072 PWID were assessed for determining the prevalence of HCV. The overall prevalence of HCV among PWID in Iran was computed to be 47% (CI 95: 39-56). The prevalence ranged between 7 and 96%. Men and subjects using a common/shared syringe were 1.46 and 3.95 times more likely to be at risk, respectively.

CONCLUSION

The findings of the present study showed that the prevalence of HCV among PWIDs in Iran is high. The support and implementation of ad hoc health-related policies and programs that reduce this should be put into action.

Accessibility of Needle and Syringe Programs and Injecting and Sharing Risk Behaviors in High Hepatitis C Virus Prevalence Settings

Background: Access to healthcare services is a basic human right. Objective: The main purpose of this study is to assess the association between accessibility of needle and syringe programs (NSP) and injecting and sharing risk behaviors. Methods: A cross-sectional study employed respondent-driving sampling (RDS) to recruit a sample of 634 people who inject drugs (PWID) from three provinces, Golestan, Ardabil, and Sistan and Baluchestan, in Iran between November 2018 and February 2019. Participants completed a questionnaire based on the WHO Drug Injecting Study Phase II survey. Results: Participants reported their accessibility of NSP services as low (6%), middle (19%), and high (75%) in the past 2 months at the time of the survey. PWID who had increased access to NSP services were less likely to report utilization of used cooker (aOR = 1.40; CI 95% 0.99-1.82), cotton (aOR = 1.30; CI 95% 0.79-1.81), and water (aOR = 1.07; CI 95% 0.89-1.26), receptive needle/syringe sharing (aOR= 1.86, 95% CI 1.69-2.03), and distributive needle/syringe sharing (aOR= 1.09, 95% CI 0.81-1.37). Conclusions/Importance: There is evidence of inequality in PWID's access to health care as they relate to the prevention of HCV transmission. An understanding of both the social determinants and prevention of injecting and sharing risk behaviors seeks to connect HCV risk reduction within the context of human rights and vulnerability.

From risk to care: the hepatitis C screening and diagnostic cascade in a primary health care clinic in Karachi, Pakistan-a cohort study

BACKGROUND

In the high-prevalence setting of Pakistan, screening, diagnosis and treatment services for chronic hepatitis C (CHC) patients are commonly offered in specialized facilities. We aimed to describe the cascade of care in a Médecins Sans Frontières primary health care clinic offering CHC care in an informal settlement in Karachi, Pakistan.

METHODS

This was a retrospective cohort analysis using routinely collected data. Three different screening algorithms were assessed among patients with one or more CHC risk factors.

RESULTS

Among the 87 348 patients attending the outpatient clinic, 5003 (6%) presented with one or more risk factors. Rapid diagnostic test (RDT) positivity was 38% overall. Approximately 60% of the CHC patients across all risk categories were in the early stage of the disease, with an aspartate aminotransferase:platelet ratio index score <1. The sequential delays in the cascade differed between the three groups, with the interval between screening and treatment initiation being the shortest in the cohort tested with GeneXpert onsite.

CONCLUSIONS

Delays between screening and treatment can be reduced by putting in place more patient-centric testing algorithms. New strategies, to better identify and treat the hidden at-risk populations, should be developed and implemented.

HCV incidence is associated with injecting partner age and HCV serostatus mixing in young adults who inject drugs in San Francisco

BACKGROUND

HCV incidence is increasing in the US, notably among younger people who inject drugs (PWID). In a cohort of young adult (age<30 years) PWID in San Francisco we examined whether 'injecting partner mixing' factors, i.e. age of partner and knowledge of their HCV serostatus, were associated with HCV transmission.

METHODS

In 448 susceptible PWID studied prospectively. All participants were asked to report characteristics and behaviors they engaged in with up to 3 injecting partners defined as "people whom you injected the most with" in the past month". These partnerships did not specify that drugs or injecting equipment was shared. HCV incidence was estimated by age of up to 3 injecting partners, categorized as: (i) all <30; (ii) mixed-age (<&≥30); and (iii) all ≥30 years and perceived knowledge of the HCV status of participants' injecting partners' HCV status. Interaction was evaluated between partnership age categories and perceived HCV status of partners.

RESULTS

Between 2006-2018, overall HCV incidence (/100 person years observation [pyo]) was 19.4 (95% CI: 16.4, 22.9). Incidence was highest in those with mixed-age partnerships: 28.5 (95% CI: 21.8, 37.1) and those whose partners were all <30 (23.9; 95% CI: 18.8, 30.4), and lowest if partners were ≥30 (7.5; 95% CI: 4.8, 11.8). In a multivariable analyses adjusting for age, sex (of index), injection frequency, and injection partnership 'monogamy', we found evidence for an interaction: the highest HCV incidence was seen in PWID whose partners were all <30 and who knew at least one of their partners was HCV-positive (58.9, 95% CI: 43.3, 80.0; p<0.01).

CONCLUSIONS

Younger injectors are more likely to acquire HCV from their similarly-aged peers, than older injecting partners. Protective seroadaptive behavior may contribute to reduce incidence. These findings can inform new HCV prevention approaches for young PWID needed to curb the HCV epidemic.

Assessing individual-level needle and syringe coverage parameters and the measurement of coverage in Melbourne, Australia: methods and impacts

Background

To assess the structure of individual-level needle and syringe coverage measurement formula, and to estimate the impact of coverage-related behaviours/parameters (instances of syringe acquisition, total syringes acquired, peer-to-peer syringe distribution, injecting frequency) on overall coverage.

Methods

Data are drawn from the Melbourne (Australia) injecting drug user cohort study, 2010-16. Data from 518 participants were analysed. We used correlations to explore the relationships between coverage parameters; pooled multiple-linear regression to estimate the effect of each parameter on coverage over time; and exploratory factor analysis to assess the relevance of each parameter within the coverage formula.

Results

A 1-unit increase in injecting frequency over time reduced coverage by 10.93 percentage points, almost twice as much as other coverage parameters. Factor analysis results indicated potential improvements to coverage formula structure.

Conclusions

Our results suggest that reducing injecting frequency amongst people who inject drugs has the largest improvement in coverage levels, indicating harm reduction services should prioritize it. We also demonstrate that coverage measurement has been inconsistent to date. We sought to refine the method to assist in generating comparable research.

Foot drop with a popliteal artery aneurysm due to heroin use: A case report

Drug addiction has become an important problem worldwide, and the number of heroin users has been rapidly increasing. There are serious complications related to intravenous drug use. Sharing injectors and using them multiple times cause septic and infective complications. Another important aspect of intravenous drug use is that it potentiates vascular damage. Contaminated injectors may induce pseudoaneurysms when applied directly into the vessel, endothelium, or surrounding tissues. Infected pseudoaneurysms may provoke necrosis, rupture, bleeding, and some dramatic results such as loss of extremity or death. Herein, we report a female case who had a history of long-term substance abuse in whom foot drop developed with a popliteal artery aneurysm.

Age-Related Differences in Past or Present Hepatitis C Virus Infection Among People Who Inject Drugs: National Human Immunodeficiency Virus Behavioral Surveillance, 8 US Cities, 2015

BACKGROUND

Historically, older people who inject drugs (PWID) have had the highest hepatitis C virus (HCV) burden; however, young PWID now account for recent increases. We assessed factors associated with past or present HCV infection (HCV antibody [anti-HCV] positive) among young (≤35 years) and older (>35 years) PWID.

METHODS

We calculated adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) to examine sociodemographic and past 12-month injection behaviors associated with HCV infection.

RESULTS

Of 4094 PWID, 55.2% were anti-HCV positive. Among young PWID, anti-HCV prevalence was 42.1% and associated with ≤high school diploma/General Education Development diploma (GED) (aPR, 1.17 [95% CI, 1.03-1.33]), receptive syringe sharing (aPR, 1.37 [95% CI, 1.21-1.56]), sharing injection equipment (aPR, 1.16 [95% CI, 1.01-1.35]), arrest history (aPR, 1.14 [95% CI, 1.02-1.29]), and injecting speedball (aPR, 1.37 [95% CI, 1.16-1.61]). Among older PWID, anti-HCV prevalence was 62.2% and associated with ≤high school diploma/GED (aPR, 1.08 [95% CI, 1.02-1.15]), sharing injection equipment (aPR, 1.08 [95% CI, 1.02-1.15]), high injection frequency (aPR, 1.16 [95% CI, 1.01-1.34]), and injecting speedball (aPR, 1.09 [95% CI, 1.01-1.16]).

CONCLUSIONS

Anti-HCV prevalence is high among PWID and varies with age. Scaling up direct-acting antiviral treatment, syringe service programs, and medication-assisted therapy is critical to mitigating transmission risk and infection burden.

Evaluation of contingency management as a strategy to improve HCV linkage to care and treatment in persons attending needle and syringe programs: A pilot study

BACKGROUND

A greater proportion of HCV-infected people who inject drugs (PWID) need to be linked to care for HCV antiviral treatment. This study sets out to evaluate the efficacy of contingency management (CM) for improving HCV linkage to care, treatment initiation, adherence, and cure for PWID recruited from a needle and syringe program.

METHODS

Between March 2015 and April 2016, 20 participants were enrolled into the CM arm, and then subsequently enrolled 20 participants in the enhanced standard of care (eSOC) arm. Participants in the eSOC arm received an expedited appointment and a round-trip transit card. Participants enrolled in the CM arm received eSOC plus $25 for up to ten HCV clinical visits and $10 for each returned weekly medication blister pack. Adherence was measured via electronic blister packs.

RESULTS

Overall the median age was 47 years; most were men (67%) and Hispanic (69%). There were no significant differences in demographic characteristics between participants in the study arms. In the CM arm 74% were linked to HCV care, compared to 30% in the eSOC arm (p = 0.01). In the CM arm, 75% (9/12) of treatment eligible participants initiated treatment, compared to 100%(4/4) in the eSOC arm (p = 0.53). All patients (9/9) achieved cure in the CM arm, as compared to 75% (3/4) of patients in the eSOC arm. There were no differences in adherence between study arms.

CONCLUSIONS

In this pilot study, contingency management led to higher rates of HCV linkage to care for PWID, as compared to standard of care. CM should be considered as a possible intervention to improve the HCV treatment cascade for PWID.

Prevalence of and risk factors for hepatitis C virus antibody among people who inject drugs in Cambodia: a national biological and behavioral survey

BACKGROUND

Hepatitis C virus (HCV) is a significant global health concern. Despite evidence of the relationship between injecting drug use and HCV, studies on HCV among people who inject drugs in developing countries remain scarce. To address this need, we conducted this study to explore the prevalence of and factors associated with HCV antibody positivity among people who inject drugs in Cambodia.

METHODS

Data used for this study were collected as part of the National Integrated Biological and Behavioral Survey among people who use and inject drugs conducted in 2017. We used the respondent-driven sampling method to recruit participants in 12 provinces for face-to-face interviews and HIV and HCV antibody testing. Weighted multivariable logistic regression analysis was conducted to identify risk factors associated with HCV antibody positivity.

RESULTS

This study included 286 people who inject drugs with a mean age of 31.6 (SD = 7.5) years. The prevalence of HCV antibody among participants in this study was 30.4%, of whom 31.0% were co-infected with HIV. After adjustment for other covariates, the odds of HCV antibody positivity was significantly higher among participants who were in the older age group of 25 to 34 (AOR = 1.85, 95% CI = 1.06-7.92) and ≥ 35 (AOR = 2.67, 95% CI = 1.24-5.71), were in Vietnamese ethnic group (AOR = 5.44, 95% CI = 2.25-13.14), were living on the streets (AOR = 3.01, 95% CI = 1.29-704), had been sent to a drug rehabilitation center in the past 12 months (AOR = 2.67, 95% CI = 1.21-5.90), had received methadone maintenance therapy in the past 12 months (AOR = 3.02, 95% CI = 1.32-6.92), and were tested positive for HIV (AOR = 3.80, 95% CI = 1.58-9.12) compared to their respective reference group.

CONCLUSION

The prevalence of HCV antibody among people who inject drugs in Cambodia is high, particularly in older and more vulnerable subgroups. Tailor-made interventions are required to increase access to culturally sensitive harm reduction interventions to prevent primary HCV infection and reinfection. In addition, there is an opportunity to expand screening, diagnosis, and treatment with new directly acting antiviral agents.

Hepatitis C virus prevalence and estimated incidence among new injectors during the opioid epidemic in New York City, 2000-2017: Protective effects of non-injecting drug use

OBJECTIVE

Assess hepatitis C virus (HCV) prevalence and incidence among person who began injecting drugs during the opioid epidemic in New York City (NYC) and identify possible new directions for reducing HCV infection among persons who inject drugs.

METHODS

846 persons who began injecting drugs between 2000 and 2017 were recruited from persons entering Mount Sinai Beth Israel substance use treatment programs. A structured interview was administered and HCV antibody testing conducted. Protective effects of non-injecting drug use were examined among persons who "reversed transitioned" to non-injecting drug use and persons who used non-injected heroin in addition to injecting.

RESULTS

Participants were 79% male, 41% White, 15% African-American, 40% Latinx, with a mean age of 35. Of those who began injecting in 2000 or later, 97 persons (11%) "reverse transitioned" back to non-injecting drug use. Reverse transitioning was strongly associated with lower HCV seroprevalence (30% versus 47% among those who continued injecting, p < 0.005). Among those who continued injecting, HCV seropositivity was inversely associated with current non-injecting heroin use (AOR = 0.72, 95%CI 0.52-0.99). HCV incidence among persons continuing to inject was estimated as 13/100 person-years. HCV seropositive persons currently injecting cocaine were particularly likely to report behavior likely to transmit HCV.

CONCLUSIONS

Similar to other locations in the US, NYC is experiencing high rates of HCV infection among persons who have begun injecting since 2000. New interventions that facilitate substitution of non-injecting for injecting drug use and that reduce transmission behavior among HCV seropositives may provide additional methods for reducing HCV transmission.

Analysis of time of drug use according to needle and syringe program operating hours in Melbourne, Australia: Effects on individual-level needle and syringe coverage

BACKGROUND

Restricted needle and syringe program (NSP) operating hours in Australia have been reported as a barrier to access for people who inject drugs (PWID). We explored the prevalence of drug use occurring outside NSP operating hours with a particular focus on its impacts on individual-level needle and syringe coverage.

METHODS

Using data from 584 participants in a cohort of PWID in Melbourne, Australia, we analyzed time and day of drug use for heroin, methamphetamine and pharmaceutical opioids. We related this drug use to the typical operating times of Melbourne's fixed-site NSPs, categorizing drug use as either "in-hours" or "out-of-hours". We explored associations with out-of-hours drug use using a generalized linear mixed model of pooled longitudinal data.

RESULTS

23% of heroin use and 50% of methamphetamine use occurred out-of-hours. In regression analysis, males and those injecting in public locations had significantly reduced odds of out-of-hours drug use. Those currently employed and those using methamphetamine (compared to heroin) had significantly increased odds of out-of-hours drug use. There was no significant association between individual-level needle and syringe coverage and hours of drug use.

CONCLUSIONS

Deficiencies in individual-level needle and syringe coverage may not be due to restricted NSP operating hours. Instead, insufficient coverage may be the result of other factors in the lives of PWID or other NSP access difficulties. These preliminary results suggest improvements to coverage in Australia may not result from increased hours of NSP operation, but instead via improvements to client targeting.

Risk factors for acquiring HCV at a healthcare center in Hidalgo, Mexico

INTRODUCTION AND AIMS

The approach to HCV infection begins with the directed search for risk factors linked to its acquisition. Therefore, our primary aim was to identify the prevalence of risk factors associated with HCV infections in insured individuals seen at the Hidalgo delegation of the IMSS.

MATERIALS AND METHODS

An observational, descriptive, cross-sectional study was conducted through validated surveys that identified major and minor risk factors. In cases of major risk factors, the Advanced Quality™ RAPID-ANTI-HCV TEST Accutrack^® tests were applied to detect anti-HCV. Patients with positive tests were referred to the Hepatology service for the diagnostic-therapeutic approach. Statistical analysis was performed through measures of central tendency and percentages.

RESULTS

A total of 528 insured individuals were surveyed (95%CI with a 5% margin of error). Two hundred eighty-two rapid tests were performed. Five of them were positive (0.94%) and belonged to the patients in the dialysis/hemodialysis group. A total of 71.2% persons had positive risk factors. The association of 2 or more factors varied from 2 to 8 factors present at the same time. Of the entire study population, 6.25% presented with 4 risk factors and 4.35% presented with 5 risk factors at the same time.

CONCLUSIONS

Nearly three quarters of the individuals surveyed were exposed to HCV acquisition. The association of 2 or more risk factors in patients demonstrated their collective potentiality for acquiring HCV. We identified persons receiving treatment with dialysis/hemodialysis and those with high-risk sexual practices as vulnerable groups for HCV infection and suggest that they receive promotion and prevention activities, as well as public policy management.

Potential geographic "hotspots" for drug-injection related transmission of HIV and HCV and for initiation into injecting drug use in New York City, 2011-2015, with implications for the current opioid epidemic in the US

OBJECTIVE

We identified potential geographic "hotspots" for drug-injecting transmission of HIV and hepatitis C virus (HCV) among persons who inject drugs (PWID) in New York City. The HIV epidemic among PWID is currently in an "end of the epidemic" stage, while HCV is in a continuing, high prevalence (> 50%) stage.

METHODS

We recruited 910 PWID entering Mount Sinai Beth Israel substance use treatment programs from 2011-2015. Structured interviews and HIV/ HCV testing were conducted. Residential ZIP codes were used as geographic units of analysis. Potential "hotspots" for HIV and HCV transmission were defined as 1) having relatively large numbers of PWID 2) having 2 or more HIV (or HCV) seropositive PWID reporting transmission risk-passing on used syringes to others, and 3) having 2 or more HIV (or HCV) seronegative PWID reporting acquisition risk-injecting with previously used needles/syringes. Hotspots for injecting drug use initiation were defined as ZIP codes with 5 or more persons who began injecting within the previous 6 years.

RESULTS

Among PWID, 96% injected heroin, 81% male, 34% White, 15% African-American, 47% Latinx, mean age 40 (SD = 10), 7% HIV seropositive, 62% HCV seropositive. Participants resided in 234 ZIP codes. No ZIP codes were identified as potential hotspots due to small numbers of HIV seropositive PWID reporting transmission risk. Four ZIP codes were identified as potential hotspots for HCV transmission. 12 ZIP codes identified as hotspots for injecting drug use initiation.

DISCUSSION

For HIV, the lack of potential hotspots is further validation of widespread effectiveness of efforts to reduce injecting-related HIV transmission. Injecting-related HIV transmission is likely to be a rare, random event. HCV prevention efforts should include focus on potential hotspots for transmission and on hotspots for initiation into injecting drug use. We consider application of methods for the current opioid epidemic in the US.

Global prevalence of injecting drug use and sociodemographic characteristics and prevalence of HIV, HBV, and HCV in people who inject drugs: a multistage systematic review

BACKGROUND

Sharing of equipment used for injecting drug use (IDU) is a substantial cause of disease burden and a contributor to blood-borne virus transmission. We did a global multistage systematic review to identify the prevalence of IDU among people aged 15-64 years; sociodemographic characteristics of and risk factors for people who inject drugs (PWID); and the prevalence of HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV) among PWID.

METHODS

Consistent with the GATHER and PRISMA guidelines and without language restrictions, we systematically searched peer-reviewed databases (MEDLINE, Embase, and PsycINFO; articles published since 2008, latest searches in June, 2017), searched the grey literature (websites and databases, searches between April and August, 2016), and disseminated data requests to international experts and agencies (requests sent in October, 2016). We searched for data on IDU prevalence, characteristics of PWID, including gender, age, and sociodemographic and risk characteristics, and the prevalence of HIV, HCV, and HBV among PWID. Eligible data on prevalence of IDU, HIV antibody, HBsAg, and HCV antibody among PWID were selected and, where multiple estimates were available, pooled for each country via random effects meta-analysis. So too were eligible data on percentage of PWID who were female; younger than 25 years; recently homeless; ever arrested; ever incarcerated; who had recently engaged in sex work, sexual risk, or injecting risk; and whose main drugs injected were opioids or stimulants. We generated regional and global estimates in line with previous global reviews.

FINDINGS

We reviewed 55 671 papers and reports, and extracted data from 1147 eligible records. Evidence of IDU was recorded in 179 of 206 countries or territories, which cover 99% of the population aged 15-64 years, an increase of 31 countries (mostly in sub-Saharan Africa and the Pacific Islands) since a review in 2008. IDU prevalence estimates were identified in 83 countries. We estimate that there are 15·6 million (95% uncertainty interval [UI] 10·2-23·7 million) PWID aged 15-64 years globally, with 3·2 million (1·6-5·1 million) women and 12·5 million (7·5-18·4 million) men. Gender composition varied by location: women were estimated to comprise 30·0% (95% UI 28·5-31·5) of PWID in North America and 33·4% (31·0-35·6) in Australasia, compared with 3·1% (2·1-4·1) in south Asia. Globally, we estimate that 17·8% (10·8-24·8) of PWID are living with HIV, 52·3% (42·4-62·1) are HCV-antibody positive, and 9·0% (5·1-13·2) are HBV surface antigen positive; there is substantial geographic variation in these levels. Globally, we estimate 82·9% (76·6-88·9) of PWID mainly inject opioids and 33·0% (24·3-42·0) mainly inject stimulants. We estimate that 27·9% (20·9-36·8) of PWID globally are younger than 25 years, 21·7% (15·8-27·9) had recently (within the past year) experienced homelessness or unstable housing, and 57·9% (50·5-65·2) had a history of incarceration.

INTERPRETATION

We identified evidence of IDU in more countries than in 2008, with the new countries largely consisting of low-income and middle-income countries in Africa. Across all countries, a substantial number of PWID are living with HIV and HCV and are exposed to multiple adverse risk environments that increase health harms.

FUNDING

Australian National Drug and Alcohol Research Centre, Australian National Health and Medical Research Council, Open Society Foundation, World Health Organization, the Global Fund, and UNAIDS.