Case-reporting of acute hepatitis B and C among injection drug users

Although public health surveillance system data are widely used to describe the epidemiology of communicable disease, occurrence of hepatitis B and C virus (HBV and HCV, respectively) infections may be misrepresented by under-reporting in injection drug users (IDUs). This study was carried out to examine the relationship between HBV and HCV incidence and case-reporting of hepatitis B and C in Seattle IDUs. Names of participants in a Seattle IDU cohort study who acquired HBV or HCV infection over a 12-month follow-up period were compared to a database of persons with acute bepatitis B and C reported to the bealth department surveillance unit over the same period. Of 2,208 IDUs enrolled in the cohort who completed a follow-up visit, 63/759 acquired HBV infection, 53/317 acquired HCV infection, and 3 subjects acquired both HBV and HCV. Of 113 cohort subjects who acquired HBV or HCV, only 2 (1.5%) cases were reported; both bad acute bepatitis B. The upper 95% confidence limit for case-reporting of bepatitis C in the cohort was 5.7%, and for hepatitis B, it was 7.5%. In this study, reporting of acute bepatitis in IDUs was extremely low, raising questions regarding the use of community surveillance data to estimate underlying incidence in that population group.     

注射毒品者丙型肝炎病毒感染率及其危险因素研究

目的了解北京市注射毒品者HCV感染状况及其危险因素,评估注射毒品人群中HIV感染高危行为流行水平,为制定预防和控制艾滋病的策略和措施提供科学依据。方法选择北京市强制戒毒所新收治的注射毒品者和自社区招募的注射毒品者作为研究对象,采用问卷调查的方法进行资料的收集,采集静脉血5ml,实验室检测HCV抗体。资料的分析采用单因素分析、多因素分析。结果北京市注射毒品者的HIV感染率和HCV感染率分别为7.33%和52.59%。多因素分析结果表明HCV感染的危险因素有在强制戒毒所(OR=2.37,95%CI为1.55~5.72)、非北京市户籍(OR=1.94,95%CI为1.05~3.45)和注射次数≥100次(OR=2.60,95%CI为1.54~7.03)。结论北京市注射毒品人群HCV的感染率高达52.59%,标志着HIV感染高危行为在这一人群中广泛存在,应立即采取相应措施控制HIV和HCV感染的进一步扩散。     

Injection drug use and the hepatitis C virus: Considerations for a targeted treatment approach-The case study of Canada

Infection with the hepatitis C virus (HCV) is a major public health burden in Canada and globally. The literature shows that injection drug use is currently the primary transmission route for HCV, and that a majority of injection drug users (IDUs) are currently infected with HCV in Canada. This article first reviews the burden of HCV within IDU populations and the transmission risks and the treatment implications speicifc to IDUs. Traditionally, IDUs have been excluded from HCV treatment unless abstaining from illicit drug use. However, recent research suggests that categorical exclusion is not medically necessary. A series of key questions about the feasibility of offering HCV treatment to IDUs in the specific Canadian context are considered, including concerns related to the motivation of treatment for IDUs, treatment delivery, treatment side effects, HCV reinfection, and the social environment. The article concludes that treatment of HCV-infected illicit drug users is both feasible and may be necessary to reduce transmission and adverse outcomes in this high-risk population.     

静脉吸毒共用注射器具方式和性行为与丙型肝炎病毒感染关系的研究

目的 了解四川省凉山州某地区静脉吸毒人群共用注射器具方式及性行为与丙型肝炎病毒(HCV)感染的关系。方法 以社区为基础使用标准化问卷调查静脉吸毒人群人口学特征和静脉吸毒共用注射器具方式、性行为情况;通过检测研究对象的HCV抗体确定是否感染HCV。结果 在静脉吸毒379人中,静脉吸毒人群HCV感染率为对71.0％(269/379)。单因素分析结果显示近3个月共用针头或注射器和既往感染梅毒在HCV感染方面差异有统计学意义。趋势性检验发现随着共用针头或注射器、共用洗针头或注射器水的频率以及共用注射器具伙伴数的增加HCV的感染率也在增加。多因素分析结果显示,近3个月共用针头或注射器。既往感染梅毒是HCV感染的危险因素,其OR值分别为1.468(95％CI:1.045～2.061)和2.914(95％CI:1.327～6.398)。未见性行为对HCV感染的影响。结论 需考虑采用定群血清流行病学研究来进一步阐明静脉吸毒共用注射器具方式及性行为同HCV感染的关系及其联系强度。     

A computer model of the spread of hepatitis C virus among injecting drug users

A number of behavioural and clinical parameters influence the transmission of an infectious agent through direct contact between two individuals. The behavioural parameters encountered in such situations are also likely to exhibit an enormous amount of variability. With the spread of hepatitis C among injecting drug users, the parameters associated with injecting behaviour play an important role in the modelling of the transmission process. Computer simulation modelling is an ideal approach to deal with a large number of parameters as well as high levels of variability without excessive simplification. The simulation model presented in this paper is tested on data from a cohort of injecting drug users and the results obtained are very encouraging from a public health perspective. The model clearly indicates that the rate at which HCV spreads through a population of injecting drug users is extremely sensitive to the interaction rate and to the probability of infection through a single contact with an infective. At the same time it shows that rate of spread is not very sensitive to initial prevalence, which is very encouraging from a public health perspective.     

Homelessness and HIV risk behaviors among injection drug users

This article uses data from an 8-year study of injection drug users to examine whether homelessness independently influenced the likelihood of engaging in human immunodeficiency virus (HIV) risk behaviors. Fixed effects regression analyses are used to estimate the associations between four different housing contexts and four different behaviours related to transmitting HIV infections. Results showed that 16% of the study group experienced homelessness at some point during the study, and that homelessness was significantly associated with a higher likelihood of frequenting shooting galleries (odds ratio=2.05), but did not have a significant effect on sharing syringes, sharing other injection drug paraphernalia, or participating in paid sex. These results provide limited support for positing homelessness as independently associated with increased levels of HIV-related risk behavior among injection drug users and highlights the need for more research that examines the housing dynamics among this population.     

Hepatitis C virus infection in injection drug users in Bavaria: risk factors for seropositivity

Background: Hepatitis C Virus (HCV) infection is the most common disease among intravenous drug users (IDUs). Patients and method: All patients admitted to the detoxification unit 1991–1997 and meeting ICD-10 diagnosis of opioid dependency were tested for anti-HCV serology. Results: Thousand and forty nine patients were included in the study. About 61.3% of the IDUs were anti-HCV positive. Increasing age (PR: 1.46; 95% CI: 1.34–1.60), living with a significant other drug user (PR: 1.17; 95% CI: 1.05–1.31), history of therapy (PR: 1.62; 95% CI: 1.50–1.74), history of imprisonment (PR: 1.48; 95% CI: 1.36–1.61), history of emergency treatment (PR: 1.23; 95% CI: 1.12–1.35), additional daily consumption of benzodiazepines (PR: 1.10; 95% CI: 1.00–2.21) or alcohol (PR: 1.26; 95% CI: 1.14–1.38), frequency of injecting heroin (daily: PR: 0.86; 95% CI: 0.78–0.96; previously: PR: 1.14; 95% CI: 1.03–1.26) and type of opioid dependency (methadone: PR: 1.26; 95% CI: 1.13–1.41) were significant factors, considered as individual factors, for positive anti-HCV serology. Using multiple logistic regression we found that older age (OR: 3.54, 95% CI: 1.30–9.67), longer duration of opioid use (OR: 5.74; 95% CI: 1.82–18.13), living with a significant other drug user (OR: 1.47; 95% CI: 1.01–2.16), history of therapy (OR: 4.87; 95% CI: 1.67–14.20), history of imprisonment (OR: 1.92; 95% CI: 1.12–3.28), history of emergency treatment (OR: 1.45; 95% CI: 1.06–1.99) and additional daily consumption of alcohol (OR: 1.49; 95% CI: 1.04–2.13) remained independently associated with positive anti-HCV serology. Conclusions: These data support the need for early prevention strategies, namely, education of teachers in schools and further training of counsellors informing IDUs of what they can do to minimise the risk of becoming infected or of transmitting infectious agents to others.     

Hepatitis C virus infection among short-term intravenous drug users in southern Taiwan

The purpose of this study was to determine the correlation between the prevalence of hepatitis C virus (HCV) infection with duration of drug use and other risk factors among drug users. This survey covered 899 male drug users from Kaohsiung Narcotic Abstention Institute and Kaohsiung prison. The prevalence of positive anti-HCV was 67.2% among intravenous drug users (IVDU) and 14.7% among non-intravenous drug users (non-IVDU). Among intravenous (IV) drug users, age and duration of drug use were independently related to HCV seropositivity. Seroprevalence rate for HCV in the IVDU group increased with increasing duration of injection use within the first seven years of drug use. However, the steepest trajectory in seroprevalence of HCV infection occurred within the first four months. Due to the high rate of HCV infection among drug users, investigation of risk behaviors should be routine in such a group. A high frequency of HCV infection was also found among short-term injectors, which indicated that early risk reduction intervention was an important measure in moderating HCV infection.     

我国吸毒人群中艾滋病病毒与丙型肝炎病毒的感染状况

相对其他人群,我国吸毒人群具有较高的艾滋病病毒与丙型肝炎病毒的感染率以及合并感染率,是影响该人群健康的主要问题之一。本文从地区分布、人群分布方面描述和比较了艾滋病病毒与丙型肝炎病毒在我国吸毒人群面的染GZ中的感染以及合并感染的情况,分析了两种病毒通过相互影响,在病毒传播与致病方面产生的危害,并对相应的防治工作提出了建议。     

昆明市静脉注射吸毒人群丙型肝炎病毒基因型分析

目的 研究云南省昆明市静脉注射吸毒人群(IDUs)中丙型肝炎病毒(HCV)基因型的流行特点。方法 2014年4－7月在昆明市连续收集276份IDUs的血浆,其中199份样品为HCV抗体阳性,提取RNA后用巢式PCR对E1E2基因和NS5B基因的部分片段进行扩增。扩增产物经基因序列测定,所得序列通过构建系统进化树确定HCV的分子亚型。结果 结合2 个基因片段,共有125份样品获得了分型结果,3b为主要的亚型,占48.8%(61/125);其他亚型按照比例依次为3a(30.4%,38/125)、6n(14.4%,18/125)、6a(3.2%,4/125)和1b(3.2%,4/125)。各HCV亚型按性别、婚姻、民族和HIV-1抗体是否阳性差异无统计学意义,按年龄分布差异有统计学意义,45岁以下组亚型多样化。分别计算不同亚型在E1E2和NS5B基因区的基因距离,结果显示3a、3b和6a亚型的基因距离大于1b和6n亚型的基因距离。3a、3b、6a 3种亚型中3b亚型毒株的基因距离大于3a亚型毒株。结论 昆明市IDUs人群中HCV存在5种亚型,3b和3a是主要毒株且在该人群中具有较长的流行时间。     

Using a jail-based survey to monitor HIV and risk behaviors among seattle area injection drug users

Routine monitoring of human immunodeficiency virus (HIV) and risk behaviors among injection drug users (IDUs) is difficult outside drug treatment settings. We developed and implemented a survey of recently arrested IDUs to describe the prevalence of HIV, drug use, and sexual behaviors among them. A probability sampling survey was instituted in the King County Correctional Facility in Seattle, Washington, to sample recently arrested IDUs at the time of booking and in the jail health clinic between 1998 and 1999. Following HIV risk assessment and blood draw, additional information on drug use practices was gathered using a standardized questionnaire. Potential participants who were released from jail early could complete the study at a nearby research storefront office. Of the 4,344 persons intercepted at booking, 503 (12%) reported injection drug use, and 201 of the IDUs (40%) participated in the study. An additional 161 IDUs were enrolled in the study from the jail health clinic. Among the 348 unduplicated subjects, HIV prevalence was 2%; in the past 6 months, 69% reported two or more shooting partners, 72% used a cooker after someone else, 60% shared a syringe to divide up drugs, and 62% injected with used needles. Only 37% reported being hepatitis C seropositive, and 8% reported hepatitis B vaccination. It was feasible to conduct a jail-based survey of recently arrested IDUs that yielded useful information. The high prevalence of reported risky drug use practices warrants ongoing monitoring and illustrates the need for improving prevention programs for HIV and hepatitis B and C in this population, including expansion of hepatitis C screening and provision of hepatitis B vaccination at the jail health clinic.     

Assessing geographic and individual level factors associated with arrests among injection drug users in California

Law enforcement strategies to reduce street-based drug activity are often concentrated in neighborhoods with high levels of social and economic disadvantage. Intensive street-level policing is associated with fear and reluctance on the part of injection drug users (IDUs) to utilize syringe exchange programs (SEPs). We aim to build on previous research by analyzing the influence of zip code and individual level factors on the probability of arrest among IDUs in California. Individual characteristics and behaviors were more strongly associated with arrest than zip code characteristics. However, living in a disadvantaged zip code exerted a protective effect against arrest after adjusting for individual level factors (AOR 0.7, 95% 0.5, 0.9). Further efforts to contextualize the circumstances surrounding an arrest, including the characteristics of the geographic setting, may be useful for understanding how law enforcement practices impact the success of SEPs and the health of injection drug users.     

Comparison of HIV infection risk behaviors among injection drug users from East and West Coast US cities

This study assessed whether behavioral differences explained higher human immunodeficiency virus (HIV) seroprevalence among injection drug users (IDUs) in three East Coast versus two West Coast cities in the United States. Sociodemographic, sexual, and injecting information were collected during semiannual face-to-face interviews. Baseline data from New York City; Baltimore, Maryland; and New Haven, Connecticut, were compared with data from Los Angeles, California, and San Jose, California. Among 1,528 East Coast and 1,149 West Coast participants, HIV seroprevalence was 21.5% and 2.3%, respectively (odds ratio [OR] 11.9; 95% confidence interval [CI] 7.9–17.8). HIV risk behaviors were common among IDUs on both coasts, and several were more common among West Coast participants. Adjusting for potential risk factors, East (vs. West) Coast of residence remained highly associated with HIV status (adjusted OR 12.14; 95% CI 7.36–20.00). Differences in HIV seroprevalence between East and West Coast cities did not reflect self-reported injection or sexual risk behavior differences. This suggests that other factors must be considered, such as the probability of having HIV-infected injection or sexual partners. Prevention efforts are needed on the West Coast to decrease HIV-associated risk behaviors among IDUs, and further efforts are also needed to reduce HIV incidence on the East Coast.     

Gender differences in sexual and injection risk behavior among active young injection drug users in San Francisco (the UFO study)

Female injection drug users (IDUs) represent a large proportion of persons infected with HIV in the United States, and women who inject drugs have a high incidence of hepatitis B virus (HBV) and hepatitis C virus (HCV) injection. Therefore, it is important to understand the role of gender in injection risk behavior and the transmission of blood-borne virus. In 2000–2002, 844 young (<30 years old) IDUs were surveyed in San Francisco. We compared self-reported risk behavior between 584 males and 260 female participants from cross-sectional baseline data. We used logistic regression to determine whether demographic, structural, and relationship variables explained increased needle borrowing, drug preparation equipment sharing, and being injected by another IDU among females compared to males. Females were significantly younger than males and were more likely to engage in needle borrowing, ancillary equipment sharing, and being injected by someone else. Females were more likely than males to report recent sexual intercourse and to have IDU sex partners. Females and males were not different with respect to education, race/ethnicity, or housing status. In logistic regression models for borrowing a used needle and sharing drug preparation equipment, increased risk in females was explained by having an injection partner who was also a sexual partner. Injecting risk was greater in the young female compared to male IDUs despite equivalent frequency of injecting. Overlapping sexual and injection partnerships were a key factor in explaining increased injection risk in females. Females were more likely to be injected by another IDU even after adjusting for years injecting, being in a relationship with another IDU, and other potential confounders. Interventions to reduce sexual and injection practices that put women at risk of contracting hepatitis and HIV are needed.     

Hygiene and uncertainty in qualitative accounts of hepatitis C transmission among drug injectors in Serbia

Hepatitis C virus (HCV) infection is a significant cause of mortality and morbidity related to injecting drug use. In Serbia, recent estimates suggest that approximately a third of drug injectors are hepatitis C positive. We undertook the first qualitative study of drug injecting in Serbia with a focus on exploring drug injectors' accounts of hepatitis C risk. Drawing upon 67 qualitative interviews with drug injectors in Belgrade, we explore accounts of hepatitis C risk and its transmission. We find that accounts portray a social context of pervasive risk in relation to hepatitis C. Hepatitis C is characterised as ubiquitous among drug injectors, and as a hardy virus with immense transmission potential. Narratives of hygiene emerge as core to accounts of transmission, in which the virus is linked to dirt, including dirty environments, dirty drugs and dirty injecting equipment. These hygiene narratives not only have symbolic function but also appear to stem from ambiguities in accounts wherein hepatitis C is conflated with the signs, symptoms and transmission routes of hepatitis A. In addition, accounts portrayed hepatitis C risk management as a responsibility of individuals in the absence of secure trust or certainty in knowledge about risk, including in relation to others' disclosed antibody status. Hygiene narratives are a core and symbolic feature of injectors' accounts of hepatitis C transmission. There is an urgent need for health promotion fostering hepatitis C risk awareness and risk avoidance among drug injectors in Serbia.     

Crystal methamphetamine use associated with non-fatal overdose among a cohort of injection drug users in Vancouver

OBJECTIVES: To evaluate the prevalence and correlates of non-fatal overdose among a polysubstance-using cohort of injection drug users (IDU) in Vancouver. STUDY DESIGN/METHODS: We evaluated factors associated with non-fatal overdose among participants enrolled in the Vancouver Injection Drug Users Study (VIDUS) using univariate statistics. Self-reports of the awareness of drugs taken and drug potency, polysubstance use, and assistance received at the time of non-fatal overdose were also recorded. RESULTS: From 1 December 2003 to 1 June 2005, 551 participants who were active injectors were followed. In total, 37 (6.7%) individuals reported experiencing a non-fatal overdose in the previous 6 months. Factors positively associated with non-fatal overdose included public injecting (odds ratio (OR)=4.74, 95% confidence interval (CI) 2.35-9.37, P<0.001), crystal methamphetamine use (OR=4.11) and injection (OR=3.63), morphine injection (OR=3.55), non-injection opiate use (OR=3.30), frequent heroin injection (OR=2.28) and sex trade work (OR=2.12). Factors negatively associated with non-fatal overdose included participation in methadone maintenance therapy (OR=0.31) and injecting alone (OR=0.36). Sixty-two percent of individuals were unaware of drug potency, 64.9% of IDU were taking other drugs at the time of overdosing, with crack being the main drug (37.0%). Fifty-four percent were assisted by ambulance personnel, 56.8% were taken to accident and emergency or hospital, 38.1% left accident and emergency or hospital before being released, and 35.1% were given Naloxone. CONCLUSION: Structural interventions are needed that seek to modify the social and contextual risks for overdose, increased access to treatment programmes, and trials of novel interventions for crystal methamphetamine users.     

Prisoners are at risk for hepatitis C transmission

Objective: Determine the incidence of hepatitis C virus antibodies among a cohort of prisoners. Design: Follow-up study of a random sample of prisoners who participated in a cross-sectional survey in 1996. Setting: 29 correctional centres in New South Wales (Australia). Participants: 181 adult prisoners (163 men and 18 women). Results: The incidence of hepatitis C virus antibody among the 90 inmates who were seronegative at the first test in 1996 was 7.1 per 100 person-years (16 seroconverters). Among the 90 inmates, 37 had re-entered the prison system following release into the community and 53 had been continuously detained. The seroconversion rate was higher among the re-entrants compared with those who had been continuously incarcerated (10.8 vs. 4.5 per 100 person-years, p=0.07). However, when the data was stratified by injecting status, the seroconversion rate in the two groups was similar. Most of the seroconverters had histories of injecting drug users (14/16). The overall incidence among injectors was 19.3 per 100 person years (95% CI: 9.1–29.2). Conclusions: Hepatitis C transmission occurs inside the prison with injecting drug use the likely cause. Among non-injectors, tattooing was the most likely mode of transmission. Harm minimisation measures with proven effectiveness need to be considered for this environment.     

Exploring the contingent reality of biomedicine: Injecting drug users,hepatitis C virus and risk1

Hepatitis C is an emerging theme of contemporary public health discourses related to illicit drug injection practices. Such discourses differentiate injecting from non-injecting users in an actuarial risk logic, targeting drug-injecting users as a population in need of support in the management of risks attributed to their practices. Public health strategies suppose, among other things, that injecting drug users adopt a homogeneous vision of hepatitis C, and of its risk, that is compatible with the reality produced by biomedicine. The majority of studies conducted on hepatitis-related risks in the context of harm reduction strategies are interested in socio-demographic factors to understand the behavioural variations within this targeted population. The meaning given to the virus and to its risk has remained marginal and the diversity of areas of construction of meaning tends to be ignored in the academic literature. Attention to this diversity indicates a complex tissue of social and communicational relations and the contingency of the symbolic instruments that people manipulate in their relation with their body and towards others; a complex tissue in which the reality of biomedicine is one among many alternative realities.