Prevalence and incidence of HCV infection among Vietnam heroin users with recent onset of injection

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 We contacted authors of identified studies for unpublished or updated data.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 Including 28 unpublished records, 125 records met the inclusion criteria.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.

Reported Low Uptake of HCV Testing among People Who Inject Drugs in Urban Vietnam

Background

HCV testing is an important first step for treatment and prevention, particularly for those who are highly vulnerable to HCV infection such as people who inject drugs (PWID). In settings where direct-acting antiretroviral medicines are becoming more available, limited information exists about who and where to target to increase the prevalence of HCV testing among PWID. This study is aimed at understanding the prevalence of HCV testing uptake and its determinants of medical services and risk behaviors.

Methods

From February 2016 to April 2017, a sample of 509 PWID was interviewed using a structured questionnaire on their history of HCV testing, confirmation, services using in the previous year as well as HCV-related knowledge, and risk behaviors. Multiple logistic regression identified factors associated with ever being tested for HCV before enrollment in the program.

Results

Approximately 33% reported ever testing for HCV. Most cited sources of testing are public hospitals and general clinics (68.9%) and outpatient clinics (18.9%). Having ever tested for HCV was positively associated with accessing health services within the prior 12 months (aOR = 2.25; 95% CI 1.11-4.58), being currently enrolled in a methadone treatment program (aOR = 2.35; 95% CI 1.34-4.08), and/or on ART treatment (aOR = 2.30; 95% CI 1.30-4.08). Those who ever delayed in seeking healthcare services for any reason were less likely to get tested for HCV (aOR = 0.54; 95% CI 0.35-0.84).

Conclusion

HCV testing prevalence is low among PWID in Hanoi despite a very high prevalence of HCV infection. To improve the cascade of HCV testing, it is critical that intervention programs scale up linkages among methadone, outpatient clinics, and HCV services, take steps to reduce stigma and discrimination in both community and, especially, in health care settings, and increase awareness of HCV for PWID by integrating HCV into routine counseling at health care services.

Towards HCV elimination among people who inject drugs in Hai Phong, Vietnam: study protocol for an effectiveness-implementation trial evaluating an integrated model of HCV care (DRIVE-C: DRug use & Infections in ViEtnam-hepatitis C)

INTRODUCTION

In Vietnam, people who inject drugs (PWID), who are the major population infected by hepatitis C virus (HCV), remain largely undiagnosed and unlinked to HCV prevention and care despite recommended universal hepatitis C treatment. The data on the outcomes of HCV treatment among PWID also remain limited in resource-limited settings. The DRug use & Infections in ViEtnam-hepatitis C (DRIVE-C) study examines the effectiveness of a model of hepatitis C screening and integrated care targeting PWID that largely uses community-based organisations (CBO) in Hai Phong, Vietnam. In a wider perspective, this model may have the potential to eliminate HCV among PWID in this city.

METHODS AND ANALYSIS

The model of care comprises large community-based mass screening, simplified treatment with direct-acting antivirals (DAAs) and major involvement of CBO for PWID reaching out, linkage to care, treatment adherence and prevention of reinfection. The effectiveness of DAA care strategy among PWID, the potential obstacles to widespread implementation and its impact at population level will be assessed. A cost-effectiveness analysis is planned to further inform policy-makers. The enrolment target is 1050 PWID, recruited from the DRIVE study in Hai Phong. After initiation of pan-genotypic treatment consisting of sofosbuvir and daclatasvir administrated for 12 weeks, with ribavirin added in cases of cirrhosis, participants are followed-up for 48 weeks. The primary outcome is the proportion of patients with sustained virological response at week 48, that will be compared with a theoretical expected rate of 70%.

ETHICS AND DISSEMINATION

The study was approved by Haiphong University of Medicine and Pharmacy's Ethics Review Board and the Vietnamese Ministry of Health. The sponsor and the investigators are committed to conducting this study in accordance with ethics principles contained in the World Medical Association's Declaration of Helsinki (Ethical Principles for Medical Research Involving Human Subjects). Informed consent is obtained before study enrolment. The data are anonymised and stored in a secure database. The study is ongoing. Results will be presented at international conferences and submitted to international peer-review journals.

TRIAL REGISTRATION NUMBER

NCT03537196.

Prevalence and Correlates of Providing and Receiving Assistance With the Transition to Injection Drug Use

Preventing the transition to injection drug use is an important public health goal, as people who inject drugs (PWID) are at high risk for overdose and acquisition of infectious disease. Initiation into drug injection is primarily a social process, often involving PWID assistance. A better understanding of the epidemiology of this phenomenon would inform interventions to prevent injection initiation and to enhance safety when assistance is provided. We conducted a systematic review of the literature to 1) characterize the prevalence of receiving (among injection-naive persons) and providing (among PWID) help or guidance with the first drug injection and 2) identify correlates associated with these behaviors. Correlates were organized as substance use behaviors, health outcomes (e.g., human immunodeficiency virus infection), or factors describing an individual's social, economic, policy, or physical environment, defined by means of Rhodes' risk environments framework. After screening of 1,164 abstracts, 57 studies were included. The prevalence of receiving assistance with injection initiation (help or guidance at the first injection) ranged 74% to 100% (n = 13 estimates). The prevalence of ever providing assistance with injection initiation varied widely (range, 13%-69%; n = 13 estimates). Injecting norms, sex/gender, and other correlates classified within Rhodes' social risk environment were commonly associated with providing and receiving assistance. Nearly all PWID receive guidance about injecting for the first time, whereas fewer PWID report providing assistance. Substantial clinical and statistical heterogeneity between studies precluded meta-analysis, and thus local-level estimates may be necessary to guide the implementation of future psychosocial and sociostructural interventions. Further, estimates of providing assistance may be downwardly biased because of social desirability factors.

HIV control programs reduce HIV incidence but not HCV incidence among people who inject drugs in HaiPhong, Vietnam

In Vietnam, harm reduction programs to control HIV among people who inject drugs (PWID) were implemented approximately 10 years ago. Since then, the HIV prevalence has declined in this population, however, the impact of these programs on the rate of new HIV and Hepatitis C (HCV) infections remains unknown as high mortality can exceed the rate of new infections. We evaluated HIV and HCV incidences in a cohort of active PWID in HaiPhong in 2014, who were recruited from a community-based respondent driven sampling (RDS) survey and followed for 1 year. Only HIV-negative or HCV-negative participants not on medication assisted treatment (MAT) were eligible. HIV/HCV serology was tested at enrollment and at 32- and 64-week follow-up visits. Among 603 RDS participants, 250 were enrolled in the cohort, including 199 HIV seronegative and 99 HCV seronegative PWID. No HIV seroconversion was reported during the 206 person-years (PY) of follow-up (HIV incidence of 0/100PY, one-sided 97.5%CI:0-1.8/100 PY). Eighteen HCV seroconversions were reported for an incidence of 19.4/100 PY (95%CI;11.5-30.7). In multivariate analysis, "Injecting more than twice daily" was associated with HCV seroconversion with an adjusted odds ratio of 5.8 (95%CI;1.8-18.1). In Hai Phong, in a context that demonstrates the effectiveness of HIV control programs, the HCV incidence remains high. New strategies such as mass access to HCV treatment should be evaluated in order to tackle HCV transmission among PWID.

Management of acute HCV infection in the era of direct-acting antiviral therapy

The management of acute HCV infection has not been standardized following the availability of direct-acting antiviral agents (DAAs) for chronic HCV infection, and substantial uncertainty exists regarding the optimal treatment regimen and duration. Despite the lack of direct evidence, the 2016 American Association for the Study of Liver Diseases (AASLD)-Infectious Diseases Society of America (IDSA) guidelines supported "the same regimens for acute HCV as recommended for chronic HCV infection … owing to high efficacy and safety", whereas the 2016 European Association for the Study of the Liver (EASL) guidelines recommended sofosbuvir-ledipasvir, sofosbuvir-velpatasvir or sofosbuvir plus daclatasvir for 8 weeks in acute HCV infection, with a longer duration of 12 weeks recommended for those infected with HIV and/or baseline HCV RNA levels >1,000,000 IU/ml. This Review outlines the epidemiology, natural history and diagnosis of acute HCV infection and provides contemporary information on DAAs for acute and recent HCV infection. The Review also discusses the 2016 AASLD-IDSA and EASL recommendations for acute HCV infection management in light of available evidence and highlights key differences in study populations and design that influence interpretation. We focus on populations at high risk of HCV transmission and acquisition, including people who inject drugs and HIV-positive men who have sex with men, and highlight the potential effects of diagnosis and treatment of acute HCV infection in contributing to HCV elimination.

The impact of HCV therapy in a high HIV-HCV prevalence population: A modeling study on people who inject drugs in Ho Chi Minh City, Vietnam

BACKGROUND

Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) coinfection is a major global health problem especially among people who inject drugs (PWID), with significant clinical implications. Mathematical models have been used to great effect to shape HIV care, but few have been proposed for HIV/HCV.

METHODS

We constructed a deterministic compartmental ODE model that incorporated layers for HIV disease progression, HCV disease progression and PWID demography. Antiretroviral therapy (ART) and Methadone Maintenance Therapy (MMT) scale-ups were modeled as from 2016 and projected forward 10 years. HCV treatment roll-out was modeled beginning in 2026, after a variety of MMT scale-up scenarios, and projected forward 10 years.

RESULTS

Our results indicate that scale-up of ART has a major impact on HIV though not on HCV burden. MMT scale-up has an impact on incidence of both infections. HCV treatment roll-out has a measurable impact on reductions of deaths, increasing multifold the mortality reductions afforded by just ART/MMT scale-ups.

CONCLUSION

HCV treatment roll-out can have major and long-lasting effects on averting PWID deaths on top of those averted by ART/MMT scale-up. Efficient intervention scale-up of HCV alongside HIV interventions is critical in Vietnam.

Current challenges and possible solutions to improve access to care and treatment for hepatitis C infection in Vietnam: a systematic review

Background

Hepatitis C infection is a major public health concern in low- and middle-income countries where an estimated 71.1 million individuals are living with chronic infection. The World Health Organization (WHO) has recently released new guidance for hepatitis C virus (HCV) treatment programs, which include improving the access to new direct-acting antiviral agents. In Vietnam, a highly populated middle-income country, the seroprevalence of HCV infection is approximately 4% and multiple genotypes co-circulate in the general population. Here we review what is currently known regarding the epidemiology of HCV in Vietnam and outline options for reducing the significant burden of morbidity and mortality in our setting.

Methods

We performed a systematic review of the currently available literature to evaluate what has been achieved to date with efforts to control HCV infection in Vietnam.

Results

This search retrieved few publications specific to Vietnam indicating a significant gap in baseline epidemiological and public health data. Key knowledge gaps identified included an understanding of the prevalence in specific high-risk groups, characterization of circulating HCV genotypes in the population and likely response to treatment, and the extent to which HCV treatment is available, accessed and utilized.

Conclusions

We conclude that there is an urgent need to perform up to date assessments of HCV disease burden in Vietnam, especially in high-risk groups, in whom incidence is high and cross infection with multiple genotypes is likely to be frequent. Coordinating renewed surveillance measures with forthcoming HCV treatment studies should initiate the traction required to achieve the WHO goal of eliminating HCV as a public health threat by 2030, at least in this region.

Exploratory social network analysis and gene sequencing in people who inject drugs infected with hepatitis C virus

Social networks facilitate the transmission of hepatitis C virus (HCV) in people who inject drugs (PWID). The aim of this study was to assess how certain network structural characteristics are related to HCV infections in PWID and to determine the most susceptible individuals for HCV transmission in a network of PWID. PWID (N = 80) from central China were recruited from a previous follow-up case-control study. Demographic and behavioural information was obtained from a computerized database for each group. HCV RNA was extracted from blood specimens. Sequences were used to construct a phylogenetic tree and to determine genetic distances. Socio-metric social links were established between participants. Network measures were calculated using UCINET. Three HCV genotypes were identified, covering five subtypes. The density of the social networks for the whole sample (N = 80), case group (n = 31) and control group (n = 49) was 0.038, 0.054 and 0.008, respectively. PWID infected with HCV were in frequent contact with others within their group. There were four pairs of nodes with genotypic distances of 0.000 that were identified and clustered in subtypes 6a and 1b; each subject pair was linked and found in one clique. Three of the five most active nodes were infected with HCV. These three nodes served as a bridge, contributing to the connection of other nodes. These findings identify susceptible individuals for HCV transmission in PWID based on their frequent contact with others in the network. These results provide data that could be used for modelling HCV transmission patterns and in public health policies.

High Proportion of HIV-HCV Coinfected Patients with Advanced Liver Fibrosis Requiring Hepatitis C Treatment in Haiphong, Northern Vietnam (ANRS 12262)

Rationale and Aims

Screening and treatment for chronic hepatitis C are very limited in Vietnam and clinical data on HCV-related liver disease in HIV-coinfected people are almost inexistent. This study aimed to assess the severity of liver fibrosis and its risk factors in HIV-HCV coinfected patients in Haiphong, Northern Vietnam.

Methods

A cross-sectional study was conducted at a HIV outpatient clinic. Consecutive HIV treated adults with positive HCV serology completed a standardised epidemiological questionnaire and had a comprehensive liver assessment including hepatic elastography (Fibroscan^®, Echosens).

Results

From February to March 2014, 104 HIV-HCV coinfected patients receiving antiretroviral therapy (ART) were prospectively enrolled (99 males, median age: 35.8 (32.7–39.6) years, median CD4 count: 504 (361–624) /mm³. Of them, 93 (89.4%) had detectable HCV RNA (median 6.19 (4.95–6.83 Log₁₀ IU/mL). Patients were mainly infected with genotypes 1a/1b (69%) and genotypes 6a/6e (26%). Forty-three patients (41.3%) had fibrosis ≥F2 including 24 patients (23.1%) with extensive fibrosis (F3) and/or cirrhosis (F4). In univariate analysis, excessive alcohol consumption, estimated time duration from HCV infection, nevirapine and lopinavir-based ARV regimen and CD4 nadir were associated factors of extensive fibrosis/cirrhosis. Alcohol abuse was the only independent factor of extensive fibrosis in multivariate analysis. Using Fibroscan^® as a gold standard, the high thresholds of AST-to-platelet ratio index (APRI) and fibrosis-4 score (FIB-4) had very good performances for the diagnosis of extensive fibrosis/cirrhosis (Se: 90 and 100%, Sp:84 and 81%, AUROCs = 0.93, 95%CI: 0.86–0.99 and 0.96 (0.92–0.99), respectively).

Conclusion

In this study, nearly 25% of HIV-HCV coinfected patients successfully treated with ART have extensive fibrosis or cirrhosis, and therefore require urgently HCV treatment.

An international perspective on using opioid substitution treatment to improve hepatitis C prevention and care for people who inject drugs: Structural barriers and public health potential

People who inject drugs (PWID) are central to the hepatitis C virus (HCV) epidemic. Opioid substitution treatment (OST) of opioid dependence has the potential to play a significant role in the public health response to HCV by serving as an HCV prevention intervention, by treating non-injection opioid dependent people who might otherwise transition to non-sterile drug injection, and by serving as a platform to engage HCV infected PWID in the HCV care continuum and link them to HCV treatment. This paper examines programmatic, structural and policy considerations for using OST as a platform to improve the HCV prevention and care continuum in 3 countries-the United States, Estonia and Viet Nam. In each country a range of interconnected factors affects the use OST as a component of HCV control. These factors include (1) that OST is not yet provided on the scale needed to adequately address illicit opioid dependence, (2) inconsistent use of OST as a platform for HCV services, (3) high costs of HCV treatment and health insurance policies that affect access to both OST and HCV treatment, and (4) the stigmatization of drug use. We see the following as important for controlling HCV transmission among PWID: (1) maintaining current HIV prevention efforts, (2) expanding efforts to reduce the stigmatization of drug use, (3) expanding use of OST as part of a coordinated public health approach to opioid dependence, HIV prevention, and HCV control efforts, (4) reductions in HCV treatment costs and expanded health system coverage to allow population level HCV treatment as prevention and OST as needed. The global expansion of OST and use of OST as a platform for HCV services should be feasible next steps in the public health response to the HCV epidemic, and is likely to be critical to efforts to eliminate or eradicate HCV.

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.

Prevalence and correlates of HCV monoinfection and HIV and HCV coinfection among persons who inject drugs in Vietnam

BACKGROUND

Vietnam bears a high burden of hepatitis C virus (HCV) and HIV infection among persons who inject drugs (PWID). The high prevalence of HCV and HIV occurs in a context of stigma and limited preventive interventions for PWID.

OBJECTIVES

This study aims to estimate the prevalence of HCV, HIV, and HIV/HCV coinfection among PWID and to explore their associations with lifetime injection behaviors.

METHODS

A total of 1434 PWID were recruited from the Thai Nguyen Province of Vietnam between 2005 and 2007. Participants responded to a structured questionnaire and provided blood samples at baseline. A cross-sectional analysis of data collected at baseline was carried out. Factors associated with HCV monoinfection and HIV/HCV coinfection were evaluated by multinomial logistic regression.

RESULTS

The prevalences of HIV and HCV were 35.1 and 88.8%, respectively, and the prevalences of HIV/HCV coinfection and HCV monoinfection were 34.8 and 53.9%, respectively. After adjusting for confounders in multivariate analysis, ever reusing a syringe and needle was found to be significantly associated with HIV monoinfection [adjusted odds ratio (AOR), 3.13; 95% confidence interval (CI), 1.99-4.94] and HIV/HCV coinfection (AOR, 3.34; 95% CI, 2.02-5.51). Ever sharing diazepam or novocaine was also found to be significantly associated with HIV monoinfection (AOR, 2.14; 95% CI, 1.38-3.32) and HIV/HCV coinfection (AOR, 2.47; 95% CI, 1.57-3.90).

CONCLUSION

Our findings demonstrate a high burden of HIV and HCV infection among PWID in Vietnam. Lifetime injection behaviors, including sharing of diazepam or novocaine, may account for the high prevalence of HIV and HCV. Improving prevention and ensuring access to care remain critically important for this vulnerable population.

Injection and sexual risk practices among young heroin users in Hanoi, Vietnam

Epidemiological data in Vietnam shows high HIV prevalence rates among injection drug users, especially in urban centres. However, there are limited data on specific practices used to prepare and inject drugs or on sexual practices among Vietnamese injectors. A street-based cross-sectional interview was conducted with 862 heroin injectors in Hanoi, Vietnam, to collect such data. Variability was seen in both injection and sexual risk, with 12.9% of current injectors reporting at least one unsafe method of drug sharing and 57.1% reporting unsafe sex in the past 30 days. These risks were strongly associated with those who engaged in unsafe injection significantly more likely to engage in unsafe sex (69.4% vs. 55.3%) and those engaging in unsafe sex significantly more likely to engage in unsafe injection (15.7% vs. 9.2%). These findings highlight the overlap of injection and sexual risk practices among Vietnamese heroin users and suggest the need for strong, broadly targeted HIV prevention activities among this population.

Associations between prescription opioid injection and Hepatitis C virus among young injection drug users

OBJECTIVE

Hepatitis C virus (HCV) incidence has been increasing among young injection drug users (IDUs). This analysis examined whether the emerging practice of prescription opioid (PO) injection is associated with self-reported HCV among young IDUs.

METHODS

Young IDUs (n = 162) aged 18-25-years-old who indicated recent misuse of prescription drugs were sampled in New York and Los Angeles during 2009-2011. Participants reported lifetime PO injection history and results from their most recent HCV test as well as demographic characteristics and lifetime drug use. Bivariate analyses examined relationships between covariates and both lifetime PO injection and HCV positivity. Poisson regression examined the associations between lifetime PO injection, HCV positivity, and significant covariates.

RESULTS

A majority reported lifetime PO injection (72.2%) and 30.9% self-reported being HCV positive. Lifetime PO injectors were nearly three times more likely to report being HCV positive than non-PO injectors (adjusted incidence rate ratio (AIRR): 2.69, p<0.05) after controlling for socio-demographic and other drug use variable. Additionally, substituting POs for heroin (AIRR: 2.27, p<0.05), growing up in a lower social class (AIRR: 1.67, p<0.05), age (AIRR: 1.12, p<0.05), age of injection initiation (AIRR: 0.87, p<0.001), and history of being prescribed stimulants (AIRR: 0.64, p<0.05) were independently associated with HCV positivity.

CONCLUSIONS

Findings suggest that PO injection should be given further consideration as a contributing factor to rising HCV infection among young adults in the US.

Substance use disorders and HIV in Vietnam since Doi Moi (Renovation): an overview

Drawing from published and gray literature, this manuscript focuses on the following topics: (1) changing patterns of substance use and abuse in Vietnam since the early 1990s; (2) the roles of substance use in the HIV epidemic; (3) the responses of the Vietnamese government and other entities (both domestic and international) to substance use disorders (SUDs) and HIV; and (4) the current research capacity in Vietnam and ways in which furthering research in Vietnam could enrich our knowledge of the linkages between SUDs and HIV and of effective measures to reduce their public health consequences. A growing number of studies during the past two decades show dynamic and still evolving twin epidemics of SUDs and HIV in Vietnam, including a shift from consumption of opium to heroin and amphetamine-type stimulants, the concurrent use of drugs, and the increasing embrace by the government of internationally recognized effective responses (including harm reduction and methadone substitution therapy). And yet, remaining issues, such as the rapid ascendance of amphetamine-type stimulant use among the country's most vulnerable populations, the lack of effective integration of SUD and HIV services for HIV-infected drug users, and the reliance on international resources for maintaining quality services, among others, are posing challenges for building sustainable Vietnamese responses. Therefore, building local research and training capacity is a crucial foundation to meet these challenges.

Decreased injecting is associated with increased alcohol consumption among injecting drug users in northern Vietnam

BACKGROUND

Reducing injecting frequency may reduce the risk of HIV infection and improve health outcomes among injection drug users (IDUs). However, the reduction of one risk behavior may be associated with an increase in other risk behaviors, including the use of other risk-associated substances. Our objective was to determine if an association exists between a reduction in injecting and level of alcohol use among IDU.

METHODS

We conducted a longitudinal analysis of data collected for a randomized controlled trial examining the efficacy of a peer education intervention in reducing HIV risk among IDU and their network members in Thai Nguyen, Vietnam. Our analysis included active male injectors (n = 629) who were study participants and attended both baseline and 3-month visits. Frequency of alcohol consumption was assessed as the number of alcoholic drinks in the past 30 days. Change in risk and outcome behaviors was calculated as the difference in frequencies of behaviors between baseline and 3-month follow-up visits. The outcome of interest was concurrent decreased drug injection and increased alcohol consumption.

RESULTS

The mean difference between baseline and 3-month follow-up of alcohol consumption and injection frequency in the past 30 days was 19.03 drinks (93.68 SD) and 20.22 injections (35.66 SD), respectively. Participants who reported reduced injection frequency were almost three times as likely to report increased alcohol consumption (OR 2.8; 95% CI, 2.0, 4.0). The proportion that both decreased injecting and increased alcohol by any amount in the past 30 days was 35.6%. In multivariate analysis higher education was significantly associated with an increase in alcohol and decrease in injecting of any amount.

CONCLUSION

Male IDU may be at risk for increasing alcohol consumption when they reduce injection frequency. Interventions with male IDU that encourage reduction of injection may need to review specific strategies to limit alcohol consumption.

Systematic review: Asian patients with chronic hepatitis C infection

BACKGROUND

Chronic hepatitis C (CHC) infection is a risk factor for both the development of end-stage liver disease and hepatocellular carcinoma (HCC). Globally, approximately 170 million people are chronically infected with the hepatitis C virus (HCV), and the majority of these individuals come from the western Pacific and Southeast Asia regions (94.6 million persons combined). CHC is an understudied and underappreciated health problem in many Asian countries and in the US, where Asians represent one of the fastest growing groups of new Americans.

AIM

To perform a systematic review of the current literature on the epidemiology, diagnosis and screening, clinical characteristics and response to anti-viral therapy of Asians with CHC.

METHODS

Using a PubMed search of 'hepatitis C' and 'Asia,' 341 original manuscripts published in peer-reviewed journals were identified, and 99 were selected based on their relevance.

RESULTS

Many Asian CHC patients do not have easily identifiable risk factors and may be underdiagnosed. Rates of HCV infection in Asians on community screening in the US are unexpectedly high, and there is a high prevalence of HCV genotype 6 in Southeast Asia and Southern China. HCV-infected Asians tend to present at older age and may have higher risk of HCC; however, they respond better to anti-viral therapy than non-Asians across all HCV genotypes.

CONCLUSIONS

Given the high HCV endemicity in Asia, lack of identifiable risk factors and favourable treatment response rates in Asians, we advocate the screening for HCV infection of all Asians who come from areas where HCV prevalence is ≥2%.

All-cause and liver-related mortality in hepatitis C infected drug users followed for 33 years: a controlled study

BACKGROUND & AIMS

The course of chronic hepatitis C virus (HCV) in injecting drug users (IDUs) has not been well described. The aim of this study was to compare long-term all-cause and liver-related mortality among anti-HCV positive IDUs with and without persisting HCV infection.

METHODS

A retrospective-prospective controlled cohort design was applied. All IDUs admitted to resident drug treatment (1970-1984) and with available stored sera were screened for anti-HCV antibody. Anti-HCV positive individuals were further tested for the presence of HCV RNA. All-cause and liver-related mortality was compared between HCV RNA positive (n=328) and HCV RNA negative individuals (n=195). The observation was accomplished through register linkage to national registers. Mean observation time was 33 years.

RESULTS

All-cause mortality rate was 1.85 (95% CI 1.62-2.11) per 100 person-years, male 2.11 (95% CI 1.84-2.46), female 1.39 (95% CI 1.07-1.79). Mortality rates were not influenced by persisting HCV infection. Main causes of death were intoxications (45.0%), suicide (9.1%), and accidents (8.2%). Liver disease was the cause of death in 7.5% of deaths among HCV RNA positive subjects. Five of 13 deaths among male IDUs with persisting HCV infection occurring after the age of 50 years were caused by liver disease.

CONCLUSIONS

The all-cause mortality in IDUs is high and with no difference between HCV RNA positive and HCV RNA negative individuals, the first three decades after HCV transmission. However, among IDUs with chronic HCV infection who have survived until 50years of age, HCV infection emerges as the main cause of death.

Prevalences and associated risk factors of HCV/HIV co-infection and HCV mono-infection among injecting drug users in a methadone maintenance treatment program in Taipei, Taiwan

BACKGROUND

Injecting drug users (IDUs) in Taiwan contributed significantly to an HIV/AIDS epidemic in 2005. In addition, studies that identified risk factors of HCV/HIV co-infection among IDUs were sparse. This study aimed to identify risk factors of HCV/HIV co-infection and HCV mono-infection, as compared with seronegativity, among injecting drug users (IDUs) at a large methadone maintenance treatment program (MMTP) in Taipei, Taiwan.

METHODS

Data from enrollment interviews and HCV and HIV testing completed by IDUs upon admission to the Taipei City Hospital MMTP from 2006-2010 were included in this cross-sectional analysis. HCV and HIV testing was repeated among re-enrollees whose HCV or HIV test results were negative at the preceding enrollment. Backward stepwise multinomial logistic regression was used to identify risk factors associated with HCV/HIV co-infection and HCV mono-infection.

RESULTS

Of the 1,447 IDUs enrolled, the prevalences of HCV/HIV co-infection, HCV mono-infection, and HIV mono-infection were 13.1%, 78.0%, and 0.4%, respectively. In backward stepwise multinomial regression analysis, after controlling for potential confounders, syringe sharing in the 6 months before MMTP enrollment was significantly positively associated with HCV/HIV co-infection (adjusted odds ratio [AOR]=27.72, 95% confidence interval [CI] 13.30-57.76). Incarceration was also significantly positively associated with HCV/HIV co-infection (AOR=2.01, 95% CI 1.71-2.37) and HCV mono-infection (AOR=1.77, 95% CI 1.52-2.06), whereas smoking amphetamine in the 6 months before MMTP enrollment was significantly inversely associated with HCV/HIV co-infection (AOR=0.44, 95% CI 0.25-0.76) and HCV mono-infection (AOR=0.49, 95% CI 0.32-0.75). HCV seroincidence was 45.25/100 person-years at risk (PYAR; 95% CI 24.74-75.92/100 PYAR) and HIV seroincidence was 0.53/100 PYAR (95% CI 0.06-1.91/100 PYAR) among re-enrolled IDUs who were HCV- or HIV-negative at the preceding enrollment.

CONCLUSIONS

IDUs enrolled in Taipei MMTPs had very high prevalences of HCV/HIV co-infection and HCV mono-infection. Interventions such as expansion of syringe exchange programs and education regarding HCV/HIV prevention should be implemented for this high-risk group of drug users.

Hepatitis C virus in Vietnam: high prevalence of infection in dialysis and multi-transfused patients involving diverse and novel virus variants

Hepatitis C virus (HCV) is a genetically diverse pathogen infecting approximately 2–3% of the world's population. Herein, we describe results of a large, multicentre serological and molecular epidemiological study cataloguing the prevalence and genetic diversity of HCV in five regions of Vietnam; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. Individuals (n = 8654) with varying risk factors for infection were analysed for the presence of HCV Ab/Ag and, in a subset of positive specimens, for HCV RNA levels (n = 475) and genotype (n = 282). In lower risk individuals, including voluntary blood donors, military recruits and pregnant women, the prevalence of infection was 0.5% (n = 26/5250). Prevalence rates were significantly higher (p<0.001) in intravenous drug users (IDUs; 55.6%, n = 556/1000), dialysis patients (26.6%, n = 153/575) commercial sex workers (CSWs; 8.7%, n = 87/1000), and recipients of multiple blood transfusions (6.0%, n = 32/529). The prevalence of HCV in dialysis patients varied but remained high in all regions (11–43%) and was associated with the receipt of blood transfusions [OR: 2.08 (1.85–2.34), p = 0.001], time from first transfusion [OR: 1.07 (1.01–1.13), p = 0.023], duration of dialysis [OR: 1.31 (1.19–1.43), p<0.001] and male gender [OR: 1.60 (1.06–2.41), p = 0.026]. Phylogenetic analysis revealed high genetic diversity, particularly amongst dialysis and multi-transfused patients, identifying subtypes 1a (33%), 1b (27%), 2a (0.4%), 3a (0.7%), 3b (1.1%), 6a (18.8%), 6e (6.0%), 6h (4.6%), 6l (6.4%) and 2 clusters of novel genotype 6 variants (2.1%). HCV genotype 1 predominated in Vietnam (60%, n = 169/282) but the proportion of infections attributable to genotype 1 varied between regions and risk groups and, in the Southern part of Vietnam, genotype 6 viruses dominated in dialysis and multi-transfused patients (73.9%). This study confirms a high prevalence of HCV infection in Vietnamese IDUs and, notably, reveals high levels of HCV infection associated with dialysis and blood transfusion.

The Cedar Project: high incidence of HCV infections in a longitudinal study of young Aboriginal people who use drugs in two Canadian cities

Background

Factors associated with HCV incidence among young Aboriginal people in Canada are still not well understood. We sought to estimate time to HCV infection and the relative hazard of risk factors associated HCV infection among young Aboriginal people who use injection drugs in two Canadian cities.

Methods

The Cedar Project is a prospective cohort study involving young Aboriginal people in Vancouver and Prince George, British Columbia, who use illicit drugs. Participants’ venous blood samples were drawn and tested for HCV antibodies. Analysis was restricted to participants who use used injection drugs at enrolment or any of follow up visit. Cox proportional hazards regression was used to identify independent predictors of time to HCV seroconversion.

Results

In total, 45 out of 148 participants seroconverted over the study period. Incidence of HCV infection was 26.3 per 100 person-years (95% Confidence Interval [CI]: 16.3, 46.1) among participants who reported using injection drugs for two years or less, 14.4 per 100 person-years (95% CI: 7.7, 28.9) among participants who had been using injection drugs for between two and five years, and 5.1 per 100 person-years (95% CI: 2.6,10.9) among participants who had been using injection drugs for over five years. Independent associations with HCV seroconversion were involvement in sex work in the last six months (Adjusted Hazard Ratio (AHR): 1.59; 95% CI: 1.05, 2.42) compared to no involvement, having been using injection drugs for less than two years (AHR: 4.14; 95% CI: 1.91, 8.94) and for between two and five years (AHR: 2.12; 95%CI: 0.94, 4.77) compared to over five years, daily cocaine injection in the last six months (AHR: 2.47; 95% CI: 1.51, 4.05) compared to less than daily, and sharing intravenous needles in the last six months (AHR: 2.56; 95% CI: 1.47, 4.49) compared to not sharing.

Conclusions

This study contributes to the limited body of research addressing HCV infection among Aboriginal people in Canada. The HCV incidence rate among Cedar Project participants who were new initiates of injection drug use underscores an urgent need for HCV and injection prevention and safety strategies aimed at supporting young people surviving injection drug use and sex work in both cities. Young people must be afforded the opportunity to provide leadership and input in the development of prevention programming.

Correlates and contexts of US injection drug initiation among undocumented Mexican migrant men who were deported from the United States

Preventing the onset of injection drug use is important in controlling the spread of HIV and other blood borne infections. Undocumented migrants in the United States face social, economic, and legal stressors that may contribute to substance abuse. Little is known about undocumented migrants' drug abuse trajectories including injection initiation. To examine the correlates and contexts of US injection initiation among undocumented migrants, we administered quantitative surveys (N = 309) and qualitative interviews (N = 23) on migration and drug abuse experiences to deported male injection drug users in Tijuana, Mexico. US injection initiation was independently associated with ever using drugs in Mexico pre-migration, younger age at first US migration, and US incarceration. Participants' qualitative interviews contextualized quantitative findings and demonstrated the significance of social contexts surrounding US injection initiation experiences. HIV prevention programs may prevent/delay US injection initiation by addressing socio-economic and migration-related stressors experienced by undocumented migrants.

Epidemiology, responses, and way forward: the silent epidemic of viral hepatitis and HIV coinfection in Vietnam

Viral hepatitis is a disease of great concern to public health that is now met by a favorable momentum to combat the global epidemic. This article is intended to highlight the importance of viral hepatitis in the Vietnam population as well in the group of people living with HIV/AIDS (PLWHA). We reviewed available data on epidemiology and response on hepatitis B virus (HBV) and hepatitis C virus (HCV) and HIV coinfection in Vietnam. The hepatitis B surface antigen (HBsAg) prevalence in the general population ranged from 5.7% to 24.7%. The anti-HCV prevalence ranged from 0.38% to 4.3% in the general population, while among people who inject drugs (PWIDs) it ranged from 31% to 97.2%. The HBV prevalence among PLWHA is similar to the general population, while HCV/HIV coinfection is concentrated in some groups. Anti-HCV prevalence among HIV-infected PWIDs can be as high as 98.5%. Developing policies for diagnosis and treatment of chronic HBV and HCV infections are critical priorities in order to prevent clinical progression to cirrhosis and liver cancer.

Treatment of hepatitis C as prevention: a modeling case study in Vietnam

BACKGROUND

Treatment of hepatitis C (HCV) is very effective, achieving a cure in 50-90% of patients. Besides its own good for individuals, this most likely translates in reduced transmission, but this phenomenon has yet to be fully explored.

METHODS AND FINDINGS

In this mathematical modeling study done in the context of Vietnam, we estimated the public health benefit that HCV therapy for injecting drug users (IDUs) may achieve. Treatment coverage of 25, 50 and 75% of chronically HCV-infected IDUs (4 years into infection) is predicted to reduce the chronic HCV viremia prevalence respectively by 21, 37 and 50%, 11 years after full scale up to the intended coverage. At a constant 50% coverage level, earlier treatment, 3, 2, and 1 year into infection is predicted to reduce the chronic HCV viremia prevalence by 46, 60 and 85%. In these later 3 scenarios, for every 100 treatment courses provided, a total of respectively 50, 61 and 94 new infections could be averted. These benefits were projected in the context of current low coverage of methadone maintenance therapy and needles/syringes exchange programs, and these services expansion showed complementary preventive benefits to HCV therapy. The program treatment commitment associated with the various scenarios is deemed reasonable. Our model projections are robust under adjustment for uncertainty in the model parameter values.

CONCLUSIONS

In this case study in Vietnam, we project that treatment of HCV for injecting drug users will have a preventative herd effect in addition to curing patients in need for therapy, achieving a substantial reduction in HCV transmission and prevalence.

Accelerated transition to injection among male heroin initiates in Hanoi, Vietnam: implications for early harm reduction interventions

This paper examines changes in the interval between first heroin smoking and onset of injection in a large, out-treatment sample of male heroin users in Hanoi, Vietnam (n = 1,115). Mean age at initiation of heroin use (smoking) was 18.4 and mean age of onset of heroin injection was 20.9 years. Full multivariate analysis indicates that the interval between first heroin use (smoking) and first heroin injection has been significantly attenuated among more recent heroin initiates (P = 0.0043), suggesting that heroin users in Vietnam may be at increased risk for exposure to HIV relatively soon after onset of heroin use, highlighting the need for behavioral interventions that target heroin smokers. Critical intervention goals include delaying the onset of injection and improved education about safer drug sharing and drug injection practices.

Liver disease in Viet Nam: screening, surveillance, management and education: a 5-year plan and call to action

Despite a high prevalence of liver disease in Viet Nam, there has been no nationwide approach to the disease and no systematic screening of at-risk individuals. Risk factors include chronic hepatitis B (estimated prevalence of 12%), chronic hepatitis C (at least 2% prevalence), and heavy consumption of alcohol among men. This combination of factors has resulted in liver cancer being the most common cause of cancer death in Viet Nam. There is a general lack of understanding by both the general public and health-care providers about the major risk to health that liver disease represents. We report here the initial steps taken as part of a comprehensive approach to liver disease that will ultimately include nationwide education for health-care providers, health educators, and the public; expansion of nationwide screening for hepatitis B and C followed by hepatitis B virus vaccination or treatment of chronic hepatitis B and/or hepatitis C; education about alcoholic liver disease; long-term surveillance for liver cancer; reduction of infection transmission related to medical, commercial, and personal re-use of contaminated needles, syringes, sharp instruments, razors, and inadequately sterilized medical equipment; and ongoing collection and analysis of data about the prevalence of all forms of liver disease and the results of the expanded screening, vaccination, and treatment programs. We report the beginning results of our pilot hepatitis B screening program. We believe that this comprehensive nationwide approach could substantially reduce the morbidity and mortality from liver disease and greatly lessen the burden in terms of both lives lost and health-care costs.

Knowledge of HIV seropositivity is a predictor for initiation of illicit drug use: incidence of drug use initiation among female sex workers in a high HIV-prevalence area of China

BACKGROUND

Drug use and sex work have had facilitative roles in the transmission of HIV/AIDS in China. Stopping drug use among sex workers may help to control the growth of the HIV/AIDS epidemic among Chinese sex workers.

METHODS

From March 2006 to November 2009, female sex workers (FSW) in Kaiyuan City, Yunnan, China were recruited into an open cohort study. Participants were interviewed and tested for drug use and HIV/sexually transmitted infection (STI) prevalence. Follow-up surveys were conducted every six months. Multivariate Cox proportional hazards regression model with time dependent variables was used to measure the associations between independent variables and drug initiation.

RESULTS

During the course of the study, 66 (8.8%) FSWs initiated drug use yielding an overall incidence of 6.0 per 100 person years (PY) (95% confidence interval [CI], 4.67-7.58). In the multivariate Cox proportional hazards regression model, being HIV-positive and aware of positive serostatus (adjusted hazard ratio [AHR] 2.6, 95% CI 1.24-5.55), age at initiation of commercial sex work <20 years (AHR 1.8, 95% CI 1.12-3.01), and working in a high-risk establishment (AHR 1.9, 95% CI 1.14-3.04) were associated with illicit drug initiation.

CONCLUSIONS

Being HIV-positive and aware of positive serostatus was the most salient predictor for the initiation of illicit drug use. Interventions offering sources of education, treatment, support, and counseling to HIV-positive FSWs need to be implemented in order to help promote self-efficacy and safe behaviors among this group of high-risk women.