Estimates of the Population Prevalence of Injection Drug Users among Hispanic Residents of Large US Metropolitan Areas

Little information exists on the population prevalence or geographic distribution of injection drug users (IDUs) who are Hispanic in the USA. Here, we present yearly estimates of IDU population prevalence among Hispanic residents of the 96 most populated US metropolitan statistical areas (MSAs) for 1992–2002. First, yearly estimates of the proportion of IDUs who were Hispanic in each MSA were created by combining data on (1) IDUs receiving drug treatment services in Substance Abuse and Mental Health Services Administration (SAMHSA)’s Treatment Entry Data System, (2) IDUs being tested in the Centers for Disease Control and Prevention (CDC) HIV-Counseling and Testing System, and (3) incident AIDS diagnoses among IDUs, supplemented by (4) data on IDUs who were living with AIDS. Then, the resulting proportions were multiplied by published yearly estimates of the number of IDUs of all racial/ethnic groups in each MSA to produce Hispanic IDU population estimates. These were divided by Hispanic population data to produce population prevalence rates. Time trends were tested using mixed-effects regression models. Hispanic IDU prevalence declined significantly on average (1992 mean = 192, median = 133; 2002 mean = 144, median = 93; units are per 10,000 Hispanics aged 15–64). The highest prevalence rates across time tended to be in smaller northeastern MSAs. Comparing the last three study years to the first three, prevalence decreased in 82% of MSAs and increased in 18%. Comparisons with data on drug-related mortality and hepatitis C mortality supported the validity of the estimates. Generally, estimates of Hispanic IDU population prevalence were higher than published estimates for non-Hispanic White residents and lower than published estimates for non-Hispanic Black residents. Further analysis indicated that the proportion of IDUs that was Hispanic decreased in 52% and increased in 48% of MSAs between 2002 and 2007. The estimates resulting from this study can be used to investigate MSA-level social and economic factors that may have contributed to variations across MSAs and to help guide prevention program planning for Hispanic IDUs within MSAs. Future research should attempt to determine to what extent these trends are applicable to Hispanic national origin subgroups.     

Estimating the Prevalence of Injection Drug Use among Black and White Adults in Large U.S. Metropolitan Areas over Time (1992–2002): Estimation Methods and Prevalence Trends

No adequate data exist on patterns of injection drug use (IDU) prevalence over time within racial/ethnic groups in U.S. geographic areas. The absence of such prevalence data limits our understanding of the causes and consequences of IDU and hampers planning efforts for IDU-related interventions. Here, we (1) describe a method of estimating IDU prevalence among non-Hispanic Black and non-Hispanic White adult residents of 95 large U.S. metropolitan statistical areas (MSAs) annually over an 11-year period (1992–2002); (2) validate the resulting prevalence estimates; and (3) document temporal trends in these prevalence estimates. IDU prevalence estimates for Black adults were calculated in several steps: we (1) created estimates of the proportion of injectors who were Black in each MSA and year by analyzing databases documenting injectors’ encounters with the healthcare system; (2) multiplied the resulting proportions by previously calculated estimates of the total number of injectors in each MSA and year (Brady et al., 2008); (3) divided the result by the number of Black adults living in each MSA each year; and (4) validated the resulting estimates by correlating them cross-sectionally with theoretically related constructs (Black- and White-specific prevalences of drug-related mortality and of mortality from hepatitis C). We used parallel methods to estimate and validate White IDU prevalence. We analyzed trends in the resulting racial/ethnic-specific IDU prevalence estimates using measures of central tendency and hierarchical linear models (HLM). Black IDU prevalence declined from a median of 279 injectors per 10,000 adults in 1992 to 156 injectors per 10,000 adults in 2002. IDU prevalence for White adults remained relatively flat over time (median values ranged between 86 and 97 injectors per 10,000 adults). HLM analyses described similar trends and suggest that declines in Black IDU prevalence decelerated over time. Both sets of IDU estimates correlated cross-sectionally adequately with validators, suggesting that they have acceptable convergent validity (range for Black IDU prevalence validation: 0.27 < r < 0.61; range for White IDU prevalence: 0.38 < r < 0.80). These data give insight, for the first time, into IDU prevalence trends among Black adults and White adults in large U.S. MSAs. The decline seen here for Black adults may partially explain recent reductions in newly reported cases of IDU-related HIV evident in surveillance data on this population. Declining Black IDU prevalence may have been produced by (1) high AIDS-related mortality rates among Black injectors in the 1990s, rates lowered by the advent of HAART; (2) reduced IDU incidence among Black drug users; and/or (3) MSA-level social processes (e.g., diminishing residential segregation). The stability of IDU prevalence among White adults between 1992 and 2002 may be a function of lower AIDS-related mortality rates in this population; relative stability (and perhaps increases in some MSAs) in initiating IDU among White drug users; and social processes. Future research should investigate the extent to which these racial/ethnic-specific IDU prevalence trends (1) explain, and are explained by, recent trends in IDU-related health outcomes, and (2) are determined by MSA-level social processes. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.

HIV Prevalence Rates among Injection Drug Users in 96 Large US Metropolitan Areas, 1992–2002

This research presents estimates of HIV prevalence rates among injection drug users (IDUs) in large US metropolitan statistical areas (MSAs) during 1992–2002. Trend data on HIV prevalence rates in geographic areas over time are important for research on determinants of changes in HIV among IDUs. Such data also provide a foundation for the design and implementation of structural interventions for preventing the spread of HIV among IDUs. Our estimates of HIV prevalence rates among IDUs in 96 US MSAs during 1992–2002 are derived from four independent sets of data: (1) research-based HIV prevalence rate estimates; (2) Centers for Disease Control and Prevention Voluntary HIV Counseling and Testing data (CDC CTS); (3) data on the number of people living with AIDS compiled by the CDC (PLWAs); and (4) estimates of HIV prevalence in the US. From these, we calculated two independent sets of estimates: (1) calculating CTS-based Method (CBM) using regression adjustments to CDC CTS; and (2) calculating the PLWA-based Method (PBM) by taking the ratio of the number of injectors living with HIV to the numbers of injectors living in the MSA. We take the mean of CBM and PBM to calculate over all HIV prevalence rates for 1992–2002. We evaluated trends in IDU HIV prevalence rates by calculating estimated annual percentage changes (EAPCs) for each MSA. During 1992–2002, HIV prevalence rates declined in 85 (88.5%) of the 96 MSAs, with EAPCs ranging from −12.9% to −2.1% (mean EAPC = −6.5%; p < 0.01). Across the 96 MSAs, collectively, the annual mean HIV prevalence rate declined from 11.2% in 1992 to 6.2 in 2002 (EAPC, −6.4%; p < 0.01). Similarly, the median HIV prevalence rate declined from 8.1% to 4.4% (EAPC, −6.5%; p < 0.01). The maximum HIV prevalence rate across the 11 years declined from 43.5% to 22.8% (EAPC, −6.7%; p < 0.01). Declining HIV prevalence rates may reflect high continuing mortality among infected IDUs, as well as primary HIV prevention for non-infected IDUs and self-protection efforts by them. These results warrant further research into the population dynamics of disease progression, access to health services, and the effects of HIV prevention interventions for IDUs. Electronic supplementary material   The online version of this article doi: contains supplementary material, which is available to authorized users.

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.     

Estimating numbers of injecting drug users in metropolitan areas for structural analyses of community vulnerability and for assessing relative degrees of service provision for injecting drug users

This article estimates the population prevalence of current injection drug users (IDUs) in 96 large US metropolitan areas to facilitate structural analyses of its predictors and sequelae and assesses the extent to which drug abuse treatment and human immunodeficiency virus (HIV) counseling and testing are made available to drug injectors in each metropolitan area. We estimated the total number of current IDUs in the United States and then allocated the large metropolitan area total among large metropolitan areas using four different multiplier methods. Mean values were used as best estimates, and their validity and limitations were assessed. Prevalence of drug injectors per 10,000 population varied from 19 to 173 (median 60; interquartile range 42–87). Proportions of drug injectors in treatment varied from 1.0% to 39.3% (median 8.6%); and the ratio of HIV counseling and testing events to the estimated number of IDUs varied from 0.013 to 0.285 (median 0.082). Despite limitations in the accuracy of these estimates, they can be used for structural analyses of the correlates and predictors of the population density of drug injectors in metropolitan areas and for assessing the extent of service delivery to drug injectors. Although service provision levels varied considerably, few if any metropolitan areas seemed to be providing adequate levels of services.     

Prevalence of Children with Special Health Care Needs in Metropolitan and Micropolitan Statistical Areas in the United States

Objectives We estimate the prevalence of children with special health care needs (CSHCN) in 70 metropolitan and four micropolitan statistical areas across the United States. Methods The data are from the 2001 National Survey of CSHCN, which was sponsored by the Maternal and Child Health Bureau and conducted by the National Center for Health Statistics. Prevalence estimates were generated for 74 metropolitan and micropolitan statistical areas (M/MSAs) and 45 individual counties that were represented by at least 1,000 children in the sample. To generate the estimates, the child-level sample weights (representative at the national and state level) were recalibrated within each M/MSA and county to match Census 2000 counts of the child population by age, sex, and Hispanic ethnicity. Results M/MSA-level and county-level prevalence of CSHCN are compared with national- and state-level prevalence, and within M/MSAs and counties, prevalence is reported by age, sex and race/ethnicity. Most, but not all, M/MSA- or county-level prevalence estimates did not differ significantly from state-level estimates. Some M/MSAs and counties that did not differ from their states in overall prevalence of CSHCN did show some differences in prevalence for certain demographic subgroups. Conclusions Metropolitan health departments and Maternal and Child Health agencies that serve urban areas may find these new small area estimates useful for program planning purposes. This study demonstrates the importance of assessing whether state estimates may approximate local area estimates of the prevalence of CSHCN.     

Injecting drug use is associated with HIV risk perception among Mexican Americans in the Rio Grande Valley of South Texas, USA

OBJECTIVES: Injecting drug use (IDU) remains an actual risk variable in human immunodeficiency virus (HIV) infection in most ethnic populations, and the association between actual risk and individual perception of HIV risk varies across studies and samples. This study aimed to examine the relationship between IDU and HIV risk perception among Mexican Americans residing in Rio Grande Valley, South Texas. STUDY DESIGN: A cross-sectional study of IDU as a predictor of HIV risk perception. METHODS: Two hundred and seventy-five participants [IDUs 11.9%, non-IDUs 88.1%] were assessed for an association between IDU and individual risk perception for HIV infection, as well as history of drug use and HIV risk perception, using Chi-squared statistic for independence and a logistic regression model for the prevalence odds ratio (POR). RESULTS: There was no statistically significant difference between IDUs and non-IDUs with respect to the sociodemographic variables, except for income and gender (P<0.05). The results indicated a statistically significant decrease in HIV risk perception among IDUs compared with non-IDUs, after adjustment for age, gender, sexual preference, history of drug use and marital status [POR 0.26, 95% confidence intervals (CI) 0.11-0.65]. Likewise, history of drug use was associated with decreased HIV risk perception (POR 0.44, 95% CI 0.22-0.98). CONCLUSIONS: These results suggest an inverse correlation between actual risk of HIV infection, such as IDU, and HIV risk perception. Therefore, assessment of HIV risk perception, which is a significant determinant of behaviour change, is essential to reduce the prevalence of HIV infection in the targeted population.     

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.     

Place matters: variation in the black/white very preterm birth rate across U.S. metropolitan areas, 2002-2004

OBJECTIVE: We reported on the distribution of very preterm (VPT) birth rates by race across metropolitan statistical areas (MSAs). METHODS: Rates of singleton VPT birth for non-Hispanic white, non-Hispanic black, and Hispanic women were calculated with National Center for Health Statistics 2002-2004 natality files for infants in 168 MSAs. Subanalysis included stratification by parity, age, smoking, maternal education, metropolitan size, region, proportion of MSA that was black, proportion of black population living below the poverty line, and indices of residential segregation. RESULTS: The mean metropolitan-level VPT birth rate was 12.3, 34.8, and 15.7 per 1,000 live births for white, black, and Hispanic women, respectively. There was virtually no overlap in the white and black distributions. The variation in mean risk across cities was three times greater for black women compared with white women. The threefold disparity in mean rate, and two- to threefold increased variation as indicated by standard deviation, was maintained in all subanalyses. CONCLUSION: Compared with white women, black women have three times the mean VPT birth risk, as well as three times the variance in city-level rates. The racial disparity in VPT birth rates was composed of characteristics that were constant across MSAs, as well as factors that varied by MSA. The increased sensitivity to place for black women was unexplained by measured maternal and metropolitan factors. Understanding determinants of differences in both the mean risk and the variation of risk among black and white women may contribute to reducing the disparity in risk between races.     

Estimation of injecting drug users in the City of Edinburgh, Scotland, and number infected with human immunodeficiency virus

OBJECTIVES: To estimate (1) the number of current and former injecting drug users (IDU) infected with human immunodeficiency virus (HIV) alive in Edinburgh, and (2) the total number of current injectors in the city. METHODS: The number of infected IDU was estimated using a local register of HIV infections with correction for incompleteness of the register. The number of injectors was estimated by two independent methods, one based on the HIV register, the other by log-linear modelling of four lists of IDU interviewed in a city-wide survey, and/or attending drug treatment agencies and family doctors because of drug use. MAIN OUTCOME MEASURES: Estimates for the period 1992-1994 of number of IDU infected with HIV, total number of IDU, and prevalence of injecting. RESULTS: The HIV register indicated that 371 infected drug users who had ever injected were alive and resident in Edinburgh. In all, 95% of infected survey respondents appeared in the register, leading to a corrected estimate of 472 infected ever injectors. From this the number of IDU currently injecting (i.e. in the previous 6 months) was estimated to be 1770 (95% CI: 1340-2240), and the prevalence of injecting as 8.0 (95% CI: 4.8-10.8) per 1000 Edinburgh residents aged 15-59 years. Log-linear modelling gave an estimate of 2070 (95% CI: 1360-2800) current injectors. CONCLUSIONS: The number of HIV-infected IDU in Edinburgh was estimated to be twice that in the larger nearby city of Glasgow, where a higher proportion of young adults currently injected drugs. Knowledge of the high prevalence of HIV in Edinburgh IDU (19.3%), the prescribing of oral substitutes, and counselling by doctors and drug workers are perceived reasons for the reduction in the prevalence of injecting which has occurred in Edinburgh in recent years. Such measures need to be continued to encourage further reduction of injecting.     

An HIV prevalence-based model for estimating urban risk populations of injection drug users and men who have sex with men

Issues of cost and complexity have limited the study of the population sizes of men who have sex with men (MSM) and injection drug users (IDUs), two groups at clearly increased risk for human immunodeficiency virus (HIV) and other acute and chronic diseases. We developed a prototypical, easily applied estimation model for these populations and applied it to Miami, Florida. This model combined HIV prevalence estimates, HIV seroprevalence rates, and census data to make plausible estimates of the number and proportion of MSM and IDUs under a number of assumptions. Sensitivity analyses were conducted to test the robustness of the model. The model suggests that approximately 9.5% (plausible range 7.7%–11.3%) of Miami males aged 18 years or older are MSM (point estimate, N=76,500), and 1.4% (plausible range 0.9%–1.9%) of the total population aged 18 years or older are IDUs (point estimate, N=23,700). Males may be about 2.5 times more likely than females to be IDUs. The estimates were reasonably robust to biases. The model was used to develop MSM and IDU population estimates in selected urban areas across Florida and should be replicable in other medium-to-large urban areas. Such estimates could be useful for behavioral surveillance and resource allocation, including enhanced targeting of community-based interventions for primary and secondary HIV prevention. Dr. Friedman is with National Development Research Institutes, Inc. Dr. Gates is with the Urban Institute.     

Use of fake identification to purchase alcohol amongst 15-16 year olds: a cross-sectional survey examining alcohol access,consumption and harm

Objectives

Injection drug users (IDUs) are at high risk for HIV, hepatitis, overdose and other harms. Greater drug treatment availability has been shown to reduce these harms among IDUs. Yet, little is known about changes in drug treatment availability for IDUs in the U.S. This paper investigates change in drug treatment coverage for IDUs in 90 metropolitan statistical areas (MSAs) during 1993-2002.

Methods

We define treatment coverage as the percent of IDUs who are in treatment. The number of IDUs in drug treatment is calculated from treatment entry data and treatment census data acquired from the Substance Abuse and Mental Health Service Administration, divided by our estimated number of IDUs in each MSA.

Results

Treatment coverage was low in 1993 (mean 6.7%; median 6.0%) and only increased to a mean of 8.3% and median of 8.0% coverage in 2002.

Conclusions

Although some MSAs experienced increases in treatment coverage over time, overall levels of coverage were low. The persistence of low drug treatment coverage for IDUs represents a failure by the U.S. health care system to prevent avoidable harms and unnecessary deaths in this population. Policy makers should expand drug treatment for IDUs to reduce blood-borne infections and community harms associated with untreated injection drug use.     

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.     

Factors contributing to practice variation in post-stroke rehabilitation.

OBJECTIVE: To analyze geographic variability in the utilization and cost of post-stroke medical care using multiple linear regression. DATA SOURCES/STUDY SETTING: A 20 percent random sample of Medicare beneficiaries with an admission to an acute care hospital for stroke during the first six months of 1991, supplemented by data from their Medicare claims and beneficiary records, the Medicare Cost Reports for hospitals and nursing homes, and the Area Resource File. STUDY DESIGN: Weighted least squares regression is used to analyze variations in post-stroke practice patterns across 151 MSAs (Metropolitan Statistical Areas). Average post-stroke costs, utilization rates, and facility lengths of stay are regressed on patient and market characteristics. DATA COLLECTION/EXTRACTION METHODS: For a six-month post-stroke interval, beneficiary-level post-stroke costs and service utilization are averaged by MSA. Variables describing market conditions are then added to these MSA-level records. PRINCIPAL FINDINGS: Patient variables rarely explain more than a third of practice variation, and often they explain substantially less than that. Market variables (with some exception) tend to be relatively less important. Finally, one-half to two-thirds of the practice variation across MSAs is unexplained by the patient and market factors measured in our data. CONCLUSIONS: A substantial portion of inter-MSA variability in utilization and intensity of post-stroke rehabilitation services cannot be explained by differences in patient characteristics. Given the large practice differences observed across MSAs, it seems unlikely that unmeasured patient differences can account for much more of the practice differences.     

Characterizing the drug-injecting networks of cocaine and heroin injectors in Montreal

BACKGROUND: There is little understanding about how the social networks of cocaine injectors are different from those of heroin users and about how such differences are associated with injection risk behaviours. Therefore, the objective of this study was to compare drug-injecting network characteristics of cocaine and heroin injectors believed to be associated with a risk of bloodborne infections. METHODS: Active injection drug users (IDUs) were recruited between April 2004 and January 2005 from three syringe exchange and two methadone treatment programs in Montreal, Canada. Characteristics of each participant and of up to 10 social network members (IDU and non-IDU) with whom frequent contact had occurred in the past month were elicited using a structured, interviewer-administered questionnaire. The current analysis focussed on the drug-injecting network members. Logistic regression was used to examine network characteristics in relation to cocaine and heroin injection. RESULTS: Of 282 study subjects, 81% used cocaine and 19% used heroin as their primary injected drug in the past 6 months. Compared to heroin injectors, participants who injected cocaine had lower odds of knowing their network members for a longer time (OR=0.92, 0.85-0.99), were more likely to report a larger IDU network (OR=1.64, 1.18-2.29) and have IDU partners who had a history of attending shooting galleries (OR=2.42, 1.05-5.56). INTERPRETATION: This study identified high-risk network-related factors associated with bloodborne infections in cocaine injectors. Prevention efforts may benefit from tailoring interventions according to type of drug used, with particular attention to the drug injecting-network of IDUs.     

云南省部分静脉吸毒者使用别人用过的注射器的情况及影响因素的累积比数模型分析

[目的]探讨静脉吸毒人员使用别人用过的注射器情况及影响因素，为有关部门控制艾滋病提供理论依据。[方法]2003--2004年，在云南省4个县（市）随机抽取968名吸毒人员进行调查，并进行多因素累积比数模型分析。[结果]968名静脉吸毒人员中，最近1个月使用别人用过的注射器的占37．5％，8．3％的经常使用。累积比数模型分析结果，文化程度高、静脉吸毒的时间长、年龄大、认为“看上去健康的人不会是HIV感染者”的吸毒者。经常使用别人用过的注射器的OR值分别为1．030、0．996，0．395、1．467；上述选人变量与偶尔使用和没有使用无统计学意义。[结论]部分静脉吸毒人员倬用别人用1寸的注射器，年龄小、文化程度高、吸毒时间短和缺乏艾滋病知识者经常使用别人用过的注射器。     

Prevalence and Characteristics of Femoral Injection among Seattle-Area Injection Drug Users

Injection drug use (IDU) into central veins, most common among long-term IDUs with no other options, can lead to severe infectious, vascular, and traumatic medical consequences. To follow-up on anecdotal reports of femoral vein injection and related medical problems in Seattle, we analyzed data from the annual survey of a community-based syringe exchange program. A total of 276 (81%) of 343 program attendees completed the survey in August 2010. Among 248 IDUs, 66% were male, 78% white, and 86% primarily injected opiates. One hundred respondents (40%) had injected into the femoral vein, 55% of whom were actively doing so, and 58% of whom reported medical complications that they attributed to the practice. Most (66%) used the femoral vein due to difficulty accessing other veins, although 61% reported other veins they could access and 67% reporting using other sites since initiating femoral injection. While injecting into muscle was more frequent among older IDUs with longer injection careers, the prevalence of femoral injection was highest among respondents in their late twenties with 2.5–6 years of injecting drugs. Multivariate analysis demonstrated an increased risk of initiating femoral injection each calendar year after 2007. Injecting into the femoral vein was also associated with white versus other race (odds ratio [OR] 2.7, 95% CI 1.3–5.4) and injection of primarily opiates versus other drugs (OR 6.3, 95% CI 1.2–32.9) and not associated with age, length of IDU career, or a history of injecting into muscle. These findings suggest a secular trend of increasing femoral injection among Seattle-area IDUs with a high rate of related medical problems. Interventions, such as education regarding the hazards of central venous injection and guidance on safe injection into peripheral veins, are needed to minimize the health consequences of femoral injection.     

Modelling the impact of prison vaccination on hepatitis B transmission within the injecting drug user population of England and Wales

A vaccination programme offering hepatitis B (HBV) vaccine at reception into prison has been introduced into selected prisons in England and Wales. The work here considers the impact of prison vaccination on the incidence and prevalence of hepatitis B virus (HBV) in the injecting drug user (IDU) population of England and Wales. A dynamic model of the transmission of HBV in IDUs is developed with key model assumptions and parameters being subject to sensitivity analyses. The base case model (that assumes that the vaccination coverage on prison reception is 5% in 2002, 10% in 2003 and then increases linearly up to 50% of prison receptions being vaccinated by 2006) predicts that the incidence of HBV in IDUs might be reduced by almost 80% in 12 years, and the HBV prevalence (IDUs ever infected by HBV) may be reduced from approximately 18% in 2002 to 7% in 2015. The model presented here demonstrates that HBV vaccination on prison reception can have a significant impact on the prevalence and incidence of HBV in the IDU population over time.     

HIV prevalence and risk behaviours among injecting drug users in six indonesian cities implications for future HIV prevention programs

ABSTRACT: BACKGROUND: The HIV prevalence among injecting drug users (IDUs) in Indonesia reached 50% in 2005. While drug use remains illegal in Indonesia, a needle and syringe program (NSP) was implemented in 2006. METHODS: In 2007, an integrated behavioural and biological surveillance survey was conducted among IDUs in six cities. IDUs were selected via time-location sampling and respondent-driven sampling. A questionnaire was administered face-to-face. IDUs from four cities were tested for HIV, syphilis, gonorrhoea and chlamydia. Factors associated with HIV were assessed using generalized estimating equations. Risk for sexual transmission of HIV was assessed among HIV-positive IDUs. RESULTS: Among 1,404 IDUs, 70% were daily injectors and 31% reported sharing needles in the past week. Most (76%) IDUs received injecting equipment from NSP in the prior week; 26% always carried a needle and those who didn't, feared police arrest. STI prevalence was low (8%). HIV prevalence was 52%; 27% among IDUs injecting less than 1 year, 35% among those injecting for 1-3 years compared to 61% in long term injectors (p < 0.001). IDUs injecting for less than 3 years were more likely to have used clean needles in the past week compared to long term injectors (p < 0.001). HIV-positive status was associated with duration of injecting, ever been imprisoned and injecting in public parks. Among HIV-infected IDUs, consistent condom use last week with steady, casual and commercial sex partners was reported by 13%, 24% and 32%, respectively. CONCLUSIONS: Although NSP uptake has possibly reduced HIV transmission among injectors with shorter injection history, the prevalence of HIV among IDUs in Indonesia remains unacceptably high. Condom use is insufficient, which advocates for strengthening prevention of sexual transmission alongside harm reduction programs.     

Developing an HIV behavioral surveillance system for injecting drug users: the National HIV Behavioral Surveillance System

While disease surveillance for HIV/AIDS is now widely conducted in the United States, effective HIV prevention programs rely primarily on changing behavior; therefore, behavioral data are needed to inform these programs. To achieve the goal of reducing HIV infections in the U.S., the Centers for Disease Control and Prevention, in cooperation with state and local health departments, implemented the National HIV Behavioral Surveillance System (NHBS) for injecting drug users (IDUs) in 25 selected metropolitan statistical areas (MSAs) throughout the United States in 2005. The surveillance system used respondent-driven sampling (RDS), a modified chain-referral method, to recruit IDUs for a survey measuring HIV-associated drug use and sexual risk behavior. RDS can produce population estimates for specific risk behaviors and demographic characteristics. Formative assessment activities-primarily the collection of qualitative data-provided information to better understand the IDU population and implement the surveillance activities in each city. This is the first behavioral surveillance system of its kind in the U.S. that will provide local and national data on risk for HIV and other blood-borne and sexually transmitted infections among IDUs for monitoring changes in the epidemic and prevention programs.