HIV incidence among injection drug users in New York City, 1992-1997: evidence for a declining epidemic

OBJECTIVES: We assessed recent (1992-1997) HIV incidence in the large HIV epidemic among injection drug users in New York City. METHODS: Data were compiled from 10 separate studies (N = 4979), including 6 cohort studies, 2 "repeat service user" studies, and 2 analyses of voluntary HIV testing and counseling services within drug treatment programs. RESULTS: In the 10 studies, 52 seroconversions were found in 6344 person-years at risk. The observed incidence rates among the 10 studies were all within a narrow range, from 0 per 100 person-years at risk to 2.96 per 100 person-years at risk. In 9 of the 10 studies, the observed incidence rate was less than 2 per 100 person-years at risk. The weighted average incidence rate was 0.7 per 100 person-years at risk. CONCLUSIONS: The recent incidence rate in New York City is quite low for a high-seroprevalence population of injection drug users. The very large HIV epidemic among injection drug users in New York City appears to have entered a "declining phase," characterized by low incidence and declining prevalence. The data suggest that very large high-seroprevalence HIV epidemics may be "reversed."     

Behavioral risk reduction in a declining HIV epidemic: injection drug users in New York City, 1990-1997

OBJECTIVES: This study assessed trends in HIV risk behaviors among injection drug users in New York City from 1990 to 1997. METHODS: Injection drug users were recruited continuously from a large drug detoxification treatment program (N = 2588) and a research storefront located in a high-drug-use area (N = 2701). Informed consent was obtained, and a trained interviewer administered a structured interview covering sociodemographics, drug use history, HIV risk behavior, and participation in syringe exchange. RESULTS: Trends were assessed for 5 risk behaviors in the 6-month period before the interview. The 3 injection risk behaviors declined significantly over time at each site (all P < .01). When data were pooled across sites, all 5 risk behaviors declined significantly over time (all P < .01). Participation in syringe exchange programs and in HIV counseling and testing increased greatly from 1990 to 1997. CONCLUSIONS: The continuing risk reduction among injection drug users indicates a "declining phase" in the large HIV epidemic in New York City. HIV prevention programs appear to be making an important contribution to the declining phase.     

西昌市静脉吸毒人群HIV发病率分析

目的在四川省西昌市静脉吸毒人群中，利用数学模型研究人类免疫缺陷病毒（HIV）发病率。方法利用对西昌市静脉吸毒人群HIV感染横断面调查获得有关数据，进行HIV数学模型分析。结果建立静脉吸毒人群中的HIV数学模型，利用横断面调查资料计算HIV发病率。结论由模型及其分析得出HIV发病率为λ=3．5％。与由队列研究所获得的发病率比较接近。     

Tuberculosis knowledge among New York City injection drug users.

Structured interviews measuring tuberculosis knowledge were administered to 494 New York City injection drug users, 31% of whom reported a history of having a reactive tuberculin skin test. Medical records review of a subsample confirmed the validity of self-reported data. Most respondents understood the mechanisms of tuberculosis transmission. Three fourths of the subjects did not fully understand the distinction between a reactive skin test and active tuberculosis, but those who reported a history of skin test reactivity were twice as likely to understand this distinction. Forty percent of subjects did not understand the importance of medication adherence. Misunderstandings, based on a recent lack of tuberculosis education, may contribute to the fear and confusion that interfere with efforts to control tuberculosis.     

HIV prevention among injection drug users: The need for integrated models

Opportunistic infections (OIs) were first recognized among injection drug users (IDUs) in New York City in 1981. By the mid-1980s, OIs had become associated with HIV infection, and attention began to focus on efforts to prevent HIV transmission among IDUs. Since then, a range of prevention strategies has been implemented and evaluated in an attempt to reduce the spread of HIV infection among drug users. These prevention strategies include (1) HIV testing and counseling and educational and behavioural interventions delivered through community outreach; (2) condom, bleach, and needle distribution and syringe access and exchange programs: (3) substance abuse treatment; and, more recently, (4) prevention interventions targeting HIV-positive IDUs. Data from evaluations of these strategies over the past 20 years have provided substantial evidence of effectiveness and have helped to inform network-based and structural interventions. Despite the cumulative empirical evidence, however, research findings have yet to be widely, disseminated, adopted, and implemented in a sustained and integrated fashion. The reasons for this are unclear, but point to a need for improved communications with program developers and community planners to facilitate the implementation and evaluation of integrated intervention strategies, and for collaborative research to help understand policy, legal, economic, and local barriers to implementation.     

Hepatitis C incidence—a comparison between injection and noninjection drug users in New York City

Hepatitis C virus (HCV) burdens injection drug users (IDUs) with prevalence estimated from 60–100% compared to around 5% among noninjection drug users (non-IDUs). We present preliminary data comparing the risk for HCV among IDUs and non-IDUs to inform new avenues of HCV prevention and intervention planning. Two cohorts, new IDUs (injecting ≤3 years) and non-IDUs (smoke/sniff heroine, crack or cocaine ≤10 years) ages 15–40, were street-recruited in New York City. Participants underwent risk surveys and HCV serology at baseline and 6-month follow-up visits. Person-time analysis was used to estimate annual HCV incidence. Of 683 non-IDUs, 653 were HCV seronegative, 422 returned for at least 1 follow-up visit, and 1 became HCV seropositive. Non-IDUs contributed 246.3 person-years (PY) yielding an annual incident rate of 0.4/100 PY (95% Confidence Interval [CI]=0.0–1.2). Of 260 IDUs, 114 were HCV seronegative, 62 returned for at least 1 follow-up visit, and 13 became HCV seropositive. IDUs contributed 36.3 PY yielding an annual incidence rate of 35.9/100 PY (95% CI=19.1–61.2). Among IDUs, HCV seroconverters tended to be younger (median age 25 vs. 28, respectively), and inject more frequently (61.5% vs. 34.7%, respectively) than nonseroconverters. These interim data suggest that IDUs may have engaged in high-risk practices prior to being identified for prevention services. Preventing or at least delaying transition into injection could increase opportunity to intervene. Identifying risk factors for transition into injection could inform early prevention to reduce onset of injection and risk of HCV. All research was approved by the New York Academy of Medicine’s Institutional Review Board and conforms to the principles embodied in the Declaration of Helsinki.     

Changes in HIV seroprevalence and related behaviors among male injection drug users who do and do not have sex with men: New York City, 1990-1999

OBJECTIVES: This study examined HIV prevalence and risk behaviors among male injection drug users (IDUs) who have sex with men and among other male IDUs. METHODS: Male IDUs were interviewed and tested for HIV at a detoxification clinic during 1990 to 1994 and 1995 to 1999. Analyses compared male IDUs who do and do not have sex with men within and between periods. RESULTS: Initially, HIV seroprevalence and risk behaviors were higher among IDUs who have sex with men. Seroprevalence (initially 60.5% vs 48.3%) declined approximately 15% in both groups, remaining higher among those who have sex with men. Generally, injection prevalence, but not sexual risk behaviors, declined. CONCLUSIONS: Male IDUs who have sex with men are more likely to engage in higher-risk behaviors and to be HIV infected. Improved intervention approaches for male IDUs who have sex with men are needed.     

HIV risk-related behaviors among injection drug users in Rome: differences between 1990 and 1992.

Temporal differences in human immunodeficiency virus (HIV) risk-related behaviors among injection drug users in Rome, Italy, were analyzed in 487 drug users recruited in 1990 and 450 recruited in 1992. Sharing of syringes decreased among self-reported HIV-positive drug users between 1990 and 1992, but there was no change in their sexual behavior. Fewer HIV-seronegative drug users reported passing on used syringes in 1992 than in 1990; however, there was no change in the percentage of seronegative subjects using previously used syringes, and a reduction in condom use with primary partners. There still exists a great potential for transmission of HIV infection among injection drug users and from injection drug users to the general population.     

Trends in the AIDS epidemic among New York City’s injection drug users: Localized or citywide?

The New York City injection drug user acquired immunodeficiency syndrome (IDU AIDS)epidemic accounts for almost one quarter of AIDS cases in IDUs in the United States. Recent studies have reported declines in seroprevalence and risk behaviors among IDUs in New York City during the 1990s. These trends, however, are based on studies primarily conducted in the city’s central borough of Manhattan. This article analyzes data from all five boroughs of New York City to examine trends over phases of the epidemic and to determine the level of prevention services available; an exploratory qualitative study was also conducted to assess access to prevention services and injection practices in areas in the “outer boroughs”. Findings indicated that (1)borough differences in services and behaviors existed from early in the epidemic; (2)services have been concentrated in Manhattan; and (3)declines in seroprevalence were greatest among Manhattan-recruited IDUs. Enhancing access to services for IDUs in the boroughs outside Manhattan may be needed to continue the positive trends in all areas of New York City.     

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.     

CDC international HIV prevention research activities among injection drug users in Thailand and Russia

The Centers for Disease Control and Prevention (CDC) has participated in collaborative HIV prevention research activities in injection drug users (IDUs) with the Bangkok Metropolitan Administration (BMA) in Bangkok, Thailand, from 1995 to the present and with the Orel AIDS Center in Orel Oblast, Russia, from 2001 to 2003. Studies in Bangkok have included an HIV prevention trial preparatory cohort from 1995 to 1998, a seroconverter cohort from 1998 to the present, a phase III trial of the AIDSVAX B/E gp 120 HIV vaccine from 1999 to 2003, and a phase II/III HIV prophylaxis trial with tenofovir scheduled to begin in 2005. Activities in Orel included a review of HIV surveillance data in 2001, focus group discussions and a case-control study with HIV-infected and-uninfected IDUs in 2001, a cross-sectional study with the female sex partners of male IDUs in 2002, and a community outreach intervention in 2002–2003. In Bangkok, 1,209 IDUs were enrolled in the preparatory cohort which revealed an HIV incidence of 5.8% per 100 person-years; 133 HIV-infected IDUs have been followed in the seroconverter cohort with >85% follow-up and HIV and tuberculosis care provided; 2,546 IDUs were enrolled in the HIV vaccine efficacy trial which was successfully completed with a followup rate of >95%, although the vaccine was not shown to be effective at reducing HIV incidence; and 1,600 IDUs will be enrolled in the daily tenofovir HIV prophylaxis trial in 2005. In Orel, initial focus group discussions and epidemiologic studies revealed low HIV knowledge and high rates of unsafe injecting and sexual practices among IDUs and their female sex partners; and educational campaigns and the community outreach intervention were developed and implemented. A steady decline in new HIV infections in IDUs was then observed in Orel in 2002–2003. CDC has participated in the conduct of successful collaborative HIV prevention research activities in Thailand and Russia over the past decade. The establishment of long-term relationships with in-country public health and community partners has been instrumental in the success of these efforts.     

Prevalence of serologic markers of HBV, HDV, HCV and HIV in non-injection drug users compared to injection drug users in Gran Canaria, Spain

Injection drug use (IDU) is one of the most significant risk factors for viral hepatitis (B, D and C) and human immunodeficiency virus (HIV) infection. However, there is little information about the risk of infection among non-injection drug users (non-IDUs). The present study was designed to perform several objectives: (a) to evaluate the prevalence of serological markers of hepatitis B, D, C virus and HIV in IDU and non-IDU patients; (b) to compare the prevalence of these markers between both groups; (c) to identify risk factors for HCV and HIV in this population; and (d) to correlate the presence of HCV and liver function. A total of 385 consecutive patients (122 IDUs and 263 non-IDUs), admitted to the Drug Dependency Treatment Unit at the Hospital Insular of Gran Canaria between 1993 to 1994, were included in the study. The serological markers of HBV, HDV, HCV and HIV were determined by ELISA and immunoblot methods. In all cases we also measured syphilis tests (RPR and FTAabs), serum aminotransferases and serum gammaglutamiltranspeptidase. Compared to the non-IDU, the IDU group presents a higher prevalence of antiHBc (55.0% vs. 20.7%, p < 0.0001), antiHCV (87.6% vs. 35.3%, p < 0.0001) and antiHIV (21.8% vs. 2.7%, p < 0.0001). There was no significant difference in RPR positivity (0.9% vs. 4.9%, p = 0.06). Delta infection was only detected in injection drug users, and the prevalence was low. Using logistic regression, the only risk factors associated with antiHCV positivity were injection drug addiction (OR: 9.2, 95% CI: 4.9–17.0) and antiHBc positivity (OR: 5.5, 95% CI: 3.0–9.9). Similarly, the associated risk factors for HIV were injection drug addiction (OR: 5.9, 95% CI: 2.3–15.0) and antiHBc positivity (OR: 3.8, 95% CI: 1.5–9.2). However, no correlation was found between antiHCV positive and antiHIV or between these markers and RPR positivity. Patients positive for antiHCV showed significant elevations in aspartate aminotransferase and alanine aminotransferase levels, when compared with patients negative for antiHCV: 65.0 vs. 39.2 U.l (p < 0.001) and 88.4 vs. 40.3 U/l (p < 0.001), respectively. We conclude that drug users have an elevated prevalence of HCV, HBV and HIV infection, even if drug use is only inhalated. On the other hand, the main risk factors associated with HCV and HIV are injection drug addiction and exposure to hepatitis B virus. Finally, in the study population, liver dysfunction is closely related to HCV infection.     

Neighborhood differences in patterns of syringe access,use, and discard among injection drug users: Implications for HIV outreach and prevention education

The article presents results from the Syringe Access, Use, and Discard: Context in AIDS Risk research project comparing two neighborhoods by (1) socioeconomic and demographic characteristics; (2) patterns of syringe access, use, and discard; and (3) encounters with a local human immunodeficiency viruslacquired immunodeficiency syndrome (HIV/AIDS) outreach project targeted to injection drug users (IDUs). The results show that IDUs in more economically advantaged neighborhoods were more likely to acquire syringes from a single source (rather than multiple sources), more likely to inject alone in their own residence (rather than public injection locales), and more likely to dispose of syringes in private garbage cans rather alleys or dumpsters. These results are further associated with the likelihood of encountering street outreach workers, with IDUs in more affluent neighborboods much less likely to have any such contacts. Based on the different patterns of access, use, and discard evident in each neighborhood, the results indicate that different and more carefully tailored local outreach and prevention strategies are urgently needed. An earlier version of this article was presented at the Annual Meeting of the American Public Health Association, Atlanta, Georgia, October 21–25, 2001.     

HIV/AIDS risk behaviors and correlates of injection drug use among drug users in Pakistan

We studied prevalence and correlates of injection drug use, awareness of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), and risky behaviors among drug users serviced by a nongovernmental organization catering to drug users in three Pakistani cities (Quetta, Peshawar, and Rawalpindi). Logistic regression analysis was used to identify correlates of injection drug use. Of 608 drug users, 99.8% were male; median age was 32 years, and 44% were married. Most (79.8%) were Pakistani; 15.3% were Afghani. The majority used heroin (98.7%), mostly by inhalation; 15.2% injected drugs. Only 41% had heard of HIV/AIDS, and 30% had been paid for donating blood. Injection drug use and needle sharing were highest in Quetta. Injecting drug users (IDUs) were nearly twice as likely to have donated blood and to have heard about HIV/AIDS compared to other drug users. Interventions to discourage transitions to injection, increase HIV testing, and safeguard the blood supply in Pakistan are urgently needed.     

Laws prohibiting over-the-counter syringe sales to injection drug users: relations to population density, HIV prevalence, and HIV incidence

OBJECTIVES: This study sought to assess relations of laws prohibiting over-the-counter syringe sales (anti-OTC laws) to population prevalence of injection drug users and HIV prevalence or incidence among 96 US metropolitan areas. METHODS: A cross-sectional analysis was used. RESULTS: Metropolitan areas with anti-OTC laws had a higher mean HIV prevalence (13.8% vs 6.7%) than other metropolitan areas (pseudo-P < .001). In 83 metropolitan areas with HIV prevalence of less than 20%, anti-OTC laws were associated with HIV incidence rates of 1% or greater (pseudo-P < .001). Population proportions of injection drug users did not vary by presence of anti-OTC laws. CONCLUSIONS: Anti-OTC laws are not associated with lower population proportions of injection drug users. Laws restricting syringe access are associated with HIV transmission and should be repealed.     

Evaluation of HIV incidence surveillance in New York City, 2006

In 2005, the New York City (NYC) Department of Health and Mental Hygiene implemented a standardized human immunodeficiency virus (HIV) incidence surveillance protocol based on the serologic testing algorithm for recent HIV seroconversion deployed nationwide by the Centers for Disease Control and Prevention (CDC). We evaluated four key attributes of NYC's HIV incidence surveillance system-simplicity, data quality, timeliness, and acceptability--using CDC's guidelines for surveillance system evaluation. The evaluation revealed that the system could potentially provide HIV incidence estimates stratified by borough and major demographic groups at about nine months after the period of interest. The system strengths include its relative simplicity and integration with routine HIV/acquired immunodeficiency syndrome surveillance. Weaknesses include lack of completeness of testing history information, a critical component of incidence estimation. Continued improvements in data completeness and timeliness will improve the currently available information to inform personnel who develop HIV-prevention programs and policy initiatives in NYC and nationally.     

Declining seroprevalence in a very large HIV epidemic: injecting drug users in New York City, 1991 to 1996.

OBJECTIVES: This study assessed recent trends in HIV seroprevalence among injecting drug users in New York City. METHODS: We analyzed temporal trends in HIV seroprevalence from 1991 through 1996 in 5 studies of injecting drug users recruited from a detoxification program, a methadone maintenance program, research storefronts in the Lower East Side and Harlem areas, and a citywide network of sexually transmitted disease clinics. A total of 11,334 serum samples were tested. RESULTS: From 1991 through 1996, HIV seroprevalence declined substantially among subjects in all 5 studies: from 53% to 36% in the detoxification program, from 45% to 29% in the methadone program, from 44% to 22% at the Lower East Side storefront, from 48% to 21% at the Harlem storefront, and from 30% to 21% in the sexually transmitted disease clinics (all P < .002 by chi 2 tests for trend). CONCLUSIONS: The reductions in HIV seroprevalence seen among injecting drug users in New York City from 1991 through 1996 indicate a new phase in this large HIV epidemic. Potential explanatory factors include the loss of HIV-seropositive individuals through disability and death and lower rates of risk behavior leading to low HIV incidence.