Incidence of HIV among injection drug users entering drug treatment programs in four US cities

We estimated seroincidence of human immunodeficiency virus (HIV) and prevalence of risk behaviors among injection drug users (IDUs) who accepted voluntary HIV testing on entry to drug treatment. Record-based incidence studies were conducted in 12 drug treatment programs in New York City (n = 890); Newark, New Jersey (n = 521); Seattle, Washington (n = 1,256); and Los Angeles, California (n = 733). Records of confidential HIV tests were abstracted for information on demographics, drug use, and HIV test results. More detailed data on risk behaviors were obtained by a standardized questionnaire. Although overall incidence rates were relatively low in this population (<1/100 person-years), there was a high prevalence of risk behaviors. Needle sharing was reported by more than one-third of the participants in each of the cities. HIV seroincidence rates were up to three-fold higher among younger ID Us. We found that HIV continued to be transmitted among ID Us who had received both drug treatment and HIV counseling and testing. HIV/AIDS (acquired immunodeficiency syndrome) prevention education should continue to be an important component of drug treatment.     

HIV seroprevalence among street-recruited injection drug and crack cocaine users in 16 US municipalities.

OBJECTIVES: This study deter- mined human immunodeficiency virus (HIV) seroprevalence and factors associated with HIV infection among street-recruited injection drug users and crack cocaine smokers. METHODS: An analysis was performed on HIV serologies and risk behaviors of 6402 injection drug users and 3383 crack smokers in 16 US municipalities in 1992 and 1993. RESULTS: HIV seroprevalence was 12.7% among injection drug users and 7.5% among crack smokers. Most high-seroprevalence municipalities (>25%) were located along the eastern seaboard of the United States. In high-seroprevalence municipalities, but not in others, HIV seroprevalence was higher for injection drug users than for crack smokers. Among injection drug users, cocaine injection, use of speedballs (cocaine or amphetamines with heroin), and sexual risk behaviors were independently associated with HIV infection. Among crack smokers, sexual risk behaviors were associated with HIV infection. CONCLUSIONS: Injection drug users and crack smokers are at high risk for HIV infection.     

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.     

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.     

Risk of hepatitis C virus infection among young adult injection drug users who share injection equipment

Designing studies to examine hepatitis C virus (HCV) transmission via the shared use of drug injection paraphernalia other than syringes is difficult because of saturation levels of HCV infection in most samples of injection drug users (IDUs). The authors measured the incidence of HCV infection in a large cohort of young IDUs from Chicago, Illinois, and determined the risk of HCV seroconversion associated with specific forms of sharing injection paraphernalia. From 1997 to 1999, serum samples obtained from 702 IDUs aged 18-30 years were screened for HCV antibodies; prevalence was 27%. Seronegative participants were tested for HCV antibodies at baseline, at 6 months, and at 12 months. During 290 person-years of follow-up, 29 participants seroconverted (incidence: 10.0/100 person-years). The adjusted relative hazard of seroconversion, controlling for demographic and drug-use covariates, was highest for sharing "cookers" (relative hazard = 4.1, 95% confidence interval: 1.4, 11.8), followed by sharing cotton filters (relative hazard = 2.4, 95% confidence interval: 1.1, 5.0). Risks associated with syringe-sharing and sharing of rinse water were elevated but not significant. After adjustment for syringe-sharing, sharing cookers remained the strongest predictor of seroconversion (relative hazard = 3.5, 95% confidence interval: 1.3, 9.9). The authors conclude that sharing of injection equipment other than syringes may be an important cause of HCV transmission between IDUs.     

HIV among injection drug users in large US metropolitan areas, 1998

This article estimates HIV prevalence rates among injection drug users (IDUs) in 95 large US metropolitan areas to facilitate social and policy analyses of HIV epidemics. HIV prevalence rates among IDUs in these metropolitan areas were calculated by taking the mean of two estimates: (1) estimates based on regression adjustments to Centers for Disease Control and Prevention (CDC) Voluntary HIV Counseling and Testing data and (2) estimates based on the ratio of the number of injectors living with HIV to the number of injectors living in the metropolitan area. The validity of the resulting estimates was assessed. HIV prevalence rates varied from 2 to 28% (median 5.9%; interquartile range 4.0–10.2%). These HIV prevalence rates correlated with similar estimates calculated for 1992 and with two theoretically related phenomena: laws against over-the-counter purchase of syringes and income inequality. Despite limitations in the accuracy of these estimates, they can be used for structural analyses of the correlates, predictors and consequences of HIV prevalence rates among drug injectors in metropolitan areas and for assessing and targeting the service needs for drug injectors.     

High HCV seroprevalence and HIV drug use risk behaviors among injection drug users in Pakistan

Introduction  

HIV and HCV risk behaviors among injection drug users (IDUs) in two urban areas in Pakistan were identified.     

HIV and hepatitis C virus infections among hanka injection drug users in central Ukraine: a cross-sectional survey

Background  

Ukraine has experienced an increase in injection drug use since the 1990s. An increase in HIV and hepatitis C virus infections has followed, but not measures of prevalence and risk factors. The purposes of this study are to estimate the prevalence of HIV, HCV, and co-infection among injection drug users (IDUs) in central Ukraine and to describe risk factors for HIV and HCV.     

An epidemic of hepatitis B virus infection among intravenous drug users in Iceland

This study describes an outbreak of hepatitis B primarily among intravenous drug users in Iceland which has a population with a very low incidence of hepatitis B virus infection. The incidence of acute hepatitis B is generally low in the Nordic Countries, in the order of one to five cases per 100,000 people per year. Between 1989 and 1992 there was an outbreak of hepatitis B virus infection primarily among the intravenous drug user (IVDU) population in Iceland. At the Department of Medical Virology, University of Iceland there were 44 cases of acute hepatitis B identified during the peak year 1990, an incidence of 16.9 cases of acute hepatitis B per 100,000 people. 63.6% of these were known to be IVDUs. The seroprevalence of the hepatitis B core antibody (anti-HBc) marker was assessed among 1100 randomly selected individuals. The average prevalence of this marker was 2.9% and rose from zero at the age of 15 and younger to 6.5% at the age of 65 and older. Among IVDUs attending a detoxification clinic in 1990 the prevalence of the anti-HBc was 32%. In contrast, those attending the same clinic, due to alcoholism only, did not have a significantly higher prevalence of anti-HBc than the group used for comparison.     

HIV, hepatitis C, and hepatitis B infections and associated risk behavior in injection drug users, Kabul, Afghanistan

Limited prevalence data for HIV, hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) exist for Afghanistan. We studied a cross-sectional sample of adult injection drug users (IDUs) in Kabul, Afghanistan, from June 2005 through June 2006. Study participants completed interviewer-administered questionnaires and underwent testing for HIV, antibody to HCV, and HBsAg. Overall prevalences of HIV, HCV, and HBsAg were 3.0% (95% confidence interval [CI] 1.7%-5.1%), 36.6% (95% CI 32.2%-41.0%), and 6.5% (95% CI 4.2%-8.7%), respectively (N = 464). Among male IDUs (n = 463), risky behavior, including sharing syringes (50.4%), paying women for sex (76.2%), and having sex with men or boys (28.3%), were common. Needle sharing, injecting for > or = 3 years, and receiving injections from nonmedical providers were independently associated with increased risk for HCV infection. The high prevalence of risky behavior indicate that Kabul is at risk for an HIV epidemic. Scale-up of harm-reducing interventions is urgently needed.     

Epidemiology of hepatitis C virus infection among injecting drug users in Australia.

STUDY OBJECTIVE: To review the epidemiology of hepatitis C virus (HCV) infection among injecting drug users (IDUs) in Australia, and consider needs for further research and prevention policies and programmes. DESIGN: (1) Review of the results of surveillance for HCV; (2) review of published literature on prevalence, incidence, and risk factors for HCV among IDUs; and (3) reconstruction of incidence rates from prevalence studies of HCV in IDUs. SETTING AND PARTICIPANTS: Field and clinic based studies of IDUs in Australia. MAIN RESULTS: HCV has been present at high prevalences (of the order of 60-70%) in populations of Australian IDUs since at least 1971. Duration of injecting and main drug injected were the main predictors of seropositivity, the latter possibly a surrogate for frequency of injecting and both together as surrogate for cumulative numbers of times injected. Risk of infection begins with first injection and continues as long as injecting does. Current incidence is approximately 15 per 100 person years, and up to 40 per 100 person years in some subpopulations. Incidence may have decreased through the 1980s as a result of behaviour change in relation to HIV, as it has for hepatitis B, but not significantly so. CONCLUSIONS: Control of HCV infection in Australia will depend on effectiveness of measures to control HCV spread among IDUs. This will be a greater challenge than the control of HIV in this population has been. Needs identified include improved surveillance, especially for recently acquired infection, better understanding of exact transmission modes, and urgent improvement in prevention strategies.     

Coinfections by HIV, hepatitis B and hepatitis C in imprisoned injecting drug users

In order to know the prevalence and risk factors for coinfections by human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among injecting drug users (IDUs), a cross-sectional study was carried out in two prisons of the province of Cantabria, northern Spain. Three hundred and sixty-two IDU inmates were recruited. All inmates were interviewed and their blood tested for HIV, HBV and HCV. Crude and multiple risk factor adjusted for (by polychotomous logistic regression) odds ratios were calculated. Prevalence of HBV-HCV coinfection (42.5%) was higher than HIV-HBV-HCV coinfection (37.3%), whereas monoinfections were very uncommon (overall: 13%). Long-term injectors and reincarceration were the foremost risk factors for both coinfections, showing a trend between the degree of association and the number of viruses infecting a patient. No significant relationship between coinfection status and sexual practices was observed. The results related to coinfections are consistent with previous studies of prevalence and risk factors for HIV, HBV and HCV, in indicating that the high rates of coinfections among IDU inmates emphasise the need to harm-reduction policy across prisons in Spain.     

Variability in the incidence of human immunodeficiency virus,hepatitis B virus,and hepatitis C virus infection among young injecting drug users in New York City

Cohort studies of young (aged 18-30 years) injecting drug users recruited in 1997-1999 in the Harlem and Lower East Side areas of New York City, New York, were used to assess the incidence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). The authors found that HIV incidence was low at both sites: 0.8/100 person-years at the Harlem site and 0/100 person-years at the Lower East Side site. In contrast, HBV incidence was moderate (12.2/100 person-years) at the Harlem site and high (30.7/100 person-years) at the Lower East Side site. Similarly, HCV incidence was moderate (9.3/100 person-years) at the Harlem site and high (34.0/100 person-years) at the Lower East Side site. Results show that high rates of HBV and HCV transmission do not imply high rates of HIV transmission, even within an area of high HIV seroprevalence.     

佛山市吸毒人群艾滋病、乙型肝炎、丙型肝炎及梅毒感染状况调查

目的 了解佛山市吸毒人群HIV、肝炎和梅毒的感染情况,为预防、控制和治疗提供参考依据。方法 对佛山市2003年部分在押吸毒人员进行HIV、HBV、HCV和梅毒血清学检测。结果 706名吸毒者血液标本中,抗-HIV、HBsAg、抗-HCV及梅毒抗体阳性率分别为3．5％、21．1％、60．1％和5．9％。在检出的25例HIV感染者中,HIV／HBV、HIV／HCV、HIV／TP双重感染率分别为32．0％(8／25)、40．0％(10／25)和4．0％(1／25),HIV／HBV／HCV三重感染率为28．0％(7／25),未发现四重感染的现象。结论 应加大对吸毒人群的监测和防病知识宣传力度,开展干预措施,降低HIV等疾病在高危人群中扩散和传播的危险性。     

Hepatitis C virus infection among injection drug users: survival analysis of time to seroconversion

BACKGROUND: Time to hepatitis C virus (HCV) seroconversion in initially seronegative injection drug users has not been directly measured, and public health planning would benefit from specifying the window of opportunity for prevention of infection, and factors that affect timing of infection. METHODS: Four hundred eighty-four HCV antibody-negative injection drug users in Seattle, Washington were followed a median of 2.1 years to observe seroconversion. We examined time to HCV seroconversion in relation to subject characteristics using the Kaplan-Meier method and Cox proportional hazards regression. A weighted-average time to HCV seroconversion was calculated among new injectors (injecting < or = 2 years) using seroprevalence and seroincidence data. RESULTS: There were 134 HCV seroconversions (11.6 per 100 person-years at risk; the 25th percentile of time to seroconversion was 26.2 months). Injection with a syringe used by another injector (adjusted hazards ratio = 1.8; 95% confidence interval = 1.3-3.0) and sharing a cooker or cotton (1.8; 1.0-3.1) were associated with time to HCV seroconversion. Using the estimate of the mean time to seroconversion from first injection in new injectors who were HCV antibody-negative at enrollment (5.4 years), and the midpoint between first injection and study enrollment in new injectors who were HCV antibody-positive at enrollment (0.6 years), the weighted-average time to seroconversion after beginning to inject was estimated to be 3.4 years. CONCLUSION: The period of susceptibility to HCV infection in the majority of drug injectors appears to be long enough to justify the allocation of substantial resources toward interventions to reduce injection-related risk behavior in these individuals.     

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。     

Sexual risk for hepatitis B virus infection among hepatitis C virus-negative heroin and cocaine users

Hepatitis C virus (HCV) and hepatitis B virus (HBV) are highly prevalent, often co-occurring infections among drug users. We examined HBV prevalence and risk behaviour patterns among a group of HCV-negative heroin and/or cocaine users in order to understand HBV risk and prevention opportunities among this unique group. Of 164 people enrolled, 44% had injected drugs. Overall, 24% of participants tested positive for exposure to HBV; drug injectors (28%) were only slightly and not significantly (P=0.287) more likely to test positive than those who had never injected drugs (21%). HBV exposure was significantly associated with multiple indicators of greater sex risk. HBV status was not associated with any demographic characteristic, but participants who reported longer duration of cocaine use were significantly less likely to test positive to exposure for HBV. It appears that HBV risk among HCV-negative drug users in this cohort is primarily due to sexual behaviour.