AIDS risk reduction and reduced HIV seroconversion among injection drug users in Bangkok

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

HIV among drug users at Beth Israel Medical Center, New York City, the first 25 years

New York City experienced the first and largest HIV epidemic among injecting drug users (IDUs). Using data collected from IDUs entering the Beth Israel drug detoxification program, we trace the history of this epidemic from the mid-1970s through the early 2000s. The epidemic can best be described in terms of successive stages: (1) introduction and rapid transmission of HIV in the IDU population; (2) stabilization of HIV prevalence at a high level (over 50%); (3) a decline in incidence and prevalence, following large-scale implementation of syringe exchange programs; and (4) a sexual transmission phase, in which HIV prevalence is approximately equal among injecting and noninjecting heroin and cocaine users, and sexual transmission is more important than injecting-related transmission among IDUs. Given the current spread of HIV among IDUs in many places in the world, New York City provides a very strong example for implementation of large-scale comprehensive syringe exchange programs as early as possible in HIV epidemics among IDUs.

Behavioral mechanisms in HIV epidemiology and prevention: past, present, and future roles

In the 1980s, behavioral variations across geographically and socially defined populations were the central focus of AIDS research, and behavior change was seen as the primary means of controlling HIV epidemics. Today, biological mechanisms--especially other sexually transmitted infections, antiretroviral therapy, and male circumcision--predominate in HIV epidemiology and prevention. We describe several reasons for this shift in emphasis. Although the shift is understandable, we argue for a sustained focus on behavioral mechanisms in HIV research in order to realize the theoretical promise of interventions targeting the biological aspects of HIV risk. We also provide evidence to suggest that large reductions in HIV prevalence may be accomplished by small changes in behavior. Moreover, we contend that behavioral mechanisms will find their proper place in HIV epidemiology and prevention only when investigators adopt a conceptual model that treats prevalence as a determinant as well as an outcome of behavior and that explicitly recognizes the dynamic interdependence between behavior and other epidemiological and demographic parameters.

Reflections on 25 Years of HIV and AIDS Research among Drug Abusers

Booth: Since early in the HIV epidemic, street outreach workers, often indigenous to the target population, have served both to recruit drug injectors for interventions and to conduct interventions. The typically unstructured nature of outreach interventions present challenges in determining the nature of services actually delivered. It is recommended that both qualitative and quantitative methods be utilized to monitor intervention service delivery. Des Jarlais: The threat of AIDS has led to profound behavioral changes among drug users. These changes need to be seen primarily not as responses to public health interventions, but in terms of the competencies of drug users themselves. A Drug User Competency Model of HIV Prevention would include: 1. Competency in understanding HIV transmission, 2. Competency in reducing HIV risk behavior, and 3. The competency of altruism. Friedman: Twenty years of work on HIV among drug users highlight that we need to incorporate large-scale social dynamics in research and interventions, understand drug users' sexual behavior and networks, and view drug users as multifaceted human beings, not just “walking addictions.” Crucially, drug users can be highly competent at many things, so non-users can learn from their ideas and their practices. Drug users can be partners and sometimes leaders, not just “disabled addicts.”

HIV prevention for injecting drug users: the first 25 years and counting

During the last three decades, both the injection of illicit psychoactive drugs and HIV infection among injecting drug users (IDUs) have spread throughout industrialized and developing countries. Extremely rapid transmission of HIV has occurred in IDU populations with incidence rates of 10 to 50/100 person-years. In sharp contrast, there are many examples of very effective HIV risk reduction for IDUs, both in preventing initial epidemics and in bringing existing epidemics under control. IDUs are capable of learning basic information about HIV/AIDS and modifying their behavior to protect both themselves and their peers. Effective HIV prevention for IDUs requires programs that treat IDUs with dignity and respect, provide accurate information and the means for behavior change-access to sterile injection equipment, condoms, and drug abuse treatment. Programs that provide these services need to be implemented on a public health scale for IDU populations at risk for HIV infection.

The Thai HIV/AIDS epidemic at 15 years: sustained needle sharing among southern Thai drug injectors

To explore perceptions and attitudes towards needle sharing among clinic-based injecting drug abusers (IDUs) at a drug-treatment clinic in Hat Yai City, Songkla Province, Southern Thailand. Qualitative methods were used to gather data, including: in-depth interviews with 17 active IDUs and with three nurses, participant observation, review of the IDUs' files, and validation after interview completion to ensure data triangulation. A form of comparative content analysis, including thematic analysis, was used for data analysis. After 15 years of the Thai HIV/AIDS epidemic, most southern Thai IDUs still occasionally engaged in needle sharing although they reported reductions in sharing frequency. Withdrawal symptoms and craving were most commonly cited as compelling reasons to share. Misconceptions about how to determine "healthy" from the "sick" was another key factor underlying sharing. Pooling money for drugs (with subsequent cost-savings) was given priority over purchasing new needles/syringes among disadvantaged IDUs. Receiving HIV voluntary counseling and testing (VCT), however, promotes reduced sharing. Our findings suggest that southern Thai IDUs remain at high risk of acquiring HIV infection, primarily through needle sharing. Harm reduction strategies, such as, providing VCT to all IDUs and promoting needle exchange programs might be beneficial approaches to curbing the rapid spread of HIV.

Interaction of cognitive performance and knowing someone who has died from AIDS on HIV risk behaviors

This study examined the association among knowledge of someone who has died from AIDS, cognitive functioning, and performance of protective health behaviors to reduce the risk of contracting HIV. Baseline data were analyzed from a sample of 229 injection drug users (IDUs) of heroin, a subset of the respondents from the Baltimore site of the International Neurobehavioral HIV Study. Multivariate logistic regression equations were fitted to predict risky injection drug use practices and sexual behavior based on cognitive performance scores and knowledge of someone who had died from AIDS. Among IDUs with lower cognitive reserves, knowing someone who had died from AIDS was associated with increased risk. This finding indicates that more intensive efforts may be required to reduce the risky behaviors among those IDUs with lower cognitive scores in higher risk social groups. Among IDUs with greater cognitive reserves, knowing someone who had died from AIDS was associated with decreased risk. This suggests that cognitive performance can provide protection to individuals in riskier social environments. These findings can aid in targeting HIV prevention efforts toward higher risk individuals within the IDU population.

Reduction in injection-related HIV risk after 6 months in a low-threshold methadone treatment program

This study assessed injection-related HIV risk behavioral changes among opioid users 6 months after enrollment in low-threshold (harm reduction based) metha-done maintenance treatment (MMT) programs within needle exchange services in Kingston and Toronto, Ontario, Canada. Changes were assessed for all participants (whole cohort), participants who continued to use illicit drugs by any route (drug-using subcohort); and those who continued to inject drugs (injecting subcohort). In this prospective observational cohort study, an interviewer-administered questionnaire examining injection-related HIV risk behaviors was administered to 183 study participants at entry to treatment and 6 months later. Changes in risk behaviors were analyzed using conditional logistic regression which took into account the paired nature of the data. We found that the proportion of participants injecting drugs, sharing needles, sharing drug equipment, indirectly sharing and using shooting galleries declined with follow-up for the whole cohort. Within the drug-using subcohort, there was a decrease in the proportion of individuals who injected drugs, while within the injecting subcohort the sharing of injection equipment and the use of shooting galleries declined. Our findings suggest that low-threshold MMT programs can reduce the risk of HIV without the enforcement of abstinence-based policies.

Background demographics and risk behaviors of injecting drug users in Karachi, Pakistan

OBJECTIVE

To find the prevalence of HIV infection and risk behaviors among injecting drug users (IDUs) in Karachi, Pakistan.

DESIGN

A cross-sectional study of IDUs conducted in Karachi, Pakistan from February through June 1996.

RESULTS

Of the 242 IDUs, 11 (4%) refused HIV testing. One (0.4%; 95% confidence interval (CI) = 0.37-0.48%) was HIV positive. All subjects were male. Over the past 6 months 47% had engaged in receptive needle sharing, 38% had perceived a change in their social network, 22% had had sexual intercourse, of whom only 7% always used condoms, and none had washed their needles with bleach. Younger age (28 vs. 31 years; p = 0.01), younger age at first injection (25 vs. 28 years; p = 0.001), fewer years of schooling (3 vs. 5 years; p = 0.001), lower monthly income (70 dollars vs. 80 dollars; p = 0.03), inhaling fumes of heroin from a foil in the year before injecting (OR = 4.8; CI = 2.2-10.3), injecting first time with heroin (OR = 3.6; CI = 1.2-12.6), having a temporary job (OR = 2.5; CI = 1.2-5.2), and a perceived change in one's social network (OR = 4.4; CI = 2.4-7.9) were all associated with receptive needle sharing. IDUs who knew about HIV spread through contaminated needles were less likely to share (OR = 0.4; CI 0.2-0.8). In the final logistic regression model receptive needle sharing was associated with inhaling of fumes of heroin on a foil in the year prior to injecting (adjusted OR = 5.6; CI = 2.6-12.0), a perceived change in one's social network (adjusted OR = 4.0; CI = 2.2-7.4), and inversely associated with age at first time of injection (beta = -0.07; p = 0.002).

CONCLUSION

Background HIV prevalence was low among IDUs in Karachi despite high-risk behavior in 1996. In order to control HIV transmission among IDUs in Pakistan, continual HIV surveillance with well-coordinated and effective HIV risk reduction, and drug demand reduction programs need to be implemented among drug users.

Prevalence of HIV, hepatitis C and syphilis among injecting drug users in Russia: a multi-city study

OBJECTIVES

To estimate the prevalence of HIV, hepatitis C virus (HCV) and syphilis in injecting drug users (IDUs) in Russia.

METHODS

Unlinked anonymous cross-sectional survey of 1473 IDUs recruited from non-treatment settings in Moscow, Volgograd and Barnaul (Siberia), with oral fluid sample collection for HIV, HCV antibody (anti-HIV, anti-HCV) and syphilis testing.

RESULTS

Prevalence of antibody to HIV was 14% in Moscow, 3% in Volgograd and 9% in Barnaul. HCV prevalence was 67% in Moscow, 70% in Volgograd and 54% in Barnaul. Prevalence of positive syphilis serology was 8% in Moscow, 20% in Volgograd and 6% in Barnaul. Half of those HIV positive and a third of those HCV positive were unaware of their positive status. Common risk factors associated with HIV and HCV infection across the cities included both direct and indirect sharing of injecting equipment and injection of home-produced drugs. Among environmental risk factors, we found increased odds of anti-HIV associated with being in prison in Moscow, and some association between official registration as a drug user and anti-HIV and anti-HCV. No associations were found between sexual risk behaviours and anti-HIV in any city.

CONCLUSIONS

HIV prevalence among IDUs was markedly higher than city routine surveillance data suggests and at potentially critical levels in terms of HIV prevention in two cities. HCV prevalence was high in all cities. Syphilis prevalence highlights the potential for sexual risk and sexual HIV transmission. Despite large-scale testing programmes, knowledge of positive status was poor. The scaling-up of harm reduction for IDUs in Russia, including sexual risk reduction, is an urgent priority.

HIV/AIDS epidemics in Vietnam: evolution and responses

The goal of this study was to describe the evolution of the HIV epidemic in Vietnam and its responses. Surveillance was conducted in 8 provinces in 1994, expanded to 12 in 1995, 20 in 1996, and 30 in 2001. Sentinel populations were sexually transmitted disease (STD) patients, female sex workers (FSWs), injection drug users (IDUs), tuberculosis (TB) patients, antenatal women, and military conscripts. Vietnam is in the concentrated epidemic stage. HIV prevalence had increased significantly in all surveillance population groups in the 1990s. HIV prevalence in the south is higher than in other regions of the country. The national HIV prevalence increased from 10.1% in 1996 to 32% in 2002 among IDUs, from 0.6% in 1994 to 6.6% in 2002 among FSWs, from 0.4% in 1994 to 2.4% in 2002 among STD patients, from 0.03% in 1994 to 0.34% in 2002 among pregnant women, from 0% in 1994 to 0.7% in 2002 among army military recruits, and from 0.5% in 1994 to 3.6% in 2002 among TB patients. The government has a strong commitment to control the epidemic and has implemented many activities for HIV prevention and control. Vietnam's HIV epidemic is predominantly among IDUs. Current intervention activities have not been sufficient to reduce HIV transmission. Vietnam needs to strengthen responses by scaling up the best practices in the most affected population groups by implementing internationally recognised effective interventions appropriately.

Needle sharing among southern Thai drug injectors

AIM

To examine factors associated with needle sharing among injecting drug users (IDU) in southern Thailand.

DESIGN

Using a cross-sectional survey, 272 active IDU were interviewed about their socio-economic background, needle sharing and drug use patterns at six drug-treatment clinics in southern Thailand.

FINDINGS

Ninety-one per cent of IDU gave a past history of ever sharing injecting equipment: of these, 23% currently injected but did not share and 68% still shared. Only 5% of participants knew that bleaching needles could reduce HIV transmission risks. Recent needle sharing was correlated with number of IDU friends (OR 12.23; CI, 5.24-28.51), engaging in illegal jobs (OR 2.74; CI, 1.13-6.67), being unable to use new needles at all times (OR 2.89; CI, 1.17-7.14) and believing that cleaning contaminated shared needles with at least plain water could reduce HIV transmission (OR 3.32; CI, 1.16-6.68).

CONCLUSIONS

Our data suggest that AIDS prevention efforts should focus on approaches to reduce needle sharing. Needle exchange programs, HIV counseling and testing and bleach distribution may reduce levels of needle-sharing risks.

Explosive spread and high prevalence of HIV infection among injecting drug users in Togliatti City, Russia

OBJECTIVE

To establish the prevalence of antibodies to HIV (anti-HIV) and associated risk factors among injecting drug users (IDU) in Togliatti City, Samara Oblast, Russian Federation.

DESIGN

An unlinked anonymous cross-sectional community recruited survey with oral fluid sample collection.

METHODS

Between September and October 2001, 426 IDU were recruited by trained fieldworkers. Participants completed an interviewer administered questionnaire, and oral fluid samples were tested for anti-HIV. Univariate and multivariate analyses compared potential risk factors for anti-HIV.

RESULTS

Anti-HIV prevalence was 56% (234/418). Three-quarters of anti-HIV-positive IDU (74%) were unaware of their positive status. In an adjusted model, the odds of HIV infection were higher among IDU who had ever injected home-produced drugs, who reported injecting with used needles and syringes in the past 4 weeks, and who were living in one particular district of the city (Komsomolksii).

CONCLUSION

The high prevalence of HIV, and a recent increase in HIV detected through routine screening tests since 2000, suggests that an explosive epidemic has occurred among IDU in Togliatti City. In the face of currently inadequate HIV prevention coverage among IDU, this has urgent implications for maximizing the distribution of sterile injecting equipment as well as for enhancing sexual risk reduction. Recognizing that it is likely that similar explosive epidemics are taking place in other Russian cities, we recommend community-wide HIV prevention coverage supported by city and state policies oriented to harm reduction.

The impact of a partially effective HIV vaccine on a population of intravenous drug users in Bangkok, Thailand: a dynamic model

Because of the variability of HIV, the first AIDS vaccine is likely to be only partially effective. There is some concern among scientists that a low-efficacy vaccine could worsen the HIV epidemic if vaccinated individuals increase their risk behavior under the false assumption of immunity. To address this concern, we constructed a dynamic compartmental model that simulated the course of the HIV/AIDS epidemic in a population of injection drug users in Bangkok, Thailand. The model calculated long-term HIV prevalence, number of AIDS cases, and total population size for two scenarios: vaccination program versus no vaccination program. We used sensitivity analyses to evaluate the impact of postvaccination risk behavior change on HIV prevalence. A 75% effective vaccine led to a 40-year HIV prevalence of 37% with vaccination and 50% without vaccination. Postvaccination behavior change had only a limited effect on the results with a 75% effective vaccine but a significant effect with a 30% effective vaccine. If 90% of low-risk individuals responded to a 30% effective vaccine with increased high-risk behavior, the benefit of vaccination disappeared. These results agree with analyses of the epidemic among gay men. If injection drug behavior is indeed modifiable, our findings have significant policy and planning implications.

Risk factors of HIV infection and needle sharing among injecting drug users in Ho Chi Minh City, Vietnam

OBJECTIVE

We sought to identify risk factors for needle sharing and HIV infection among injecting drug users (IDUs) in Ho Chi Minh City (HCMC), Vietnam.

METHODS

Three cross-sectional surveys among IDUs, both on the street (in 11 urban districts) and in the rehabilitation center for IDUs in HCMC, were carried out in April of 1995, 1997, and 1998. Outreach workers interviewed IDUs about socio-demographic characteristics, drug use and sexual practices, and HIV knowledge and perceptions. The IDUs were also tested for seropositivity to HIV. Independent predictors for HIV positivity and needle sharing were determined by univariate and multivariate logistic regression for the study sample within the rehabilitation center in 1997 and for that on the street in 1998.

RESULTS

The HIV prevalence in 1998 among IDUs was 44% for those on the street and 38.5% for those in the rehabilitation center. Independent predictors for HIV infection in IDUs were being injected by drug dealers (for the 1997 sample), injecting on the street, and sharing the drug pots (for the 1998 sample). The reported rate of needle sharing was low and decreased significantly from 20% in 1995 to 12% in 1998 for the sample of IDUs at the street. In the multivariate analysis, predictors for needle sharing for both study samples were injecting on the street, injecting at shooting galleries, and having shared needles in the past. Adequate and easy access to sterile needles and syringes, and a supportive environment of behavior change, especially in street and shooting gallery could reduce risks of virus transmission in the Vietnamese IDU community.

Continued high HIV-1 incidence in a vaccine trial preparatory cohort of injection drug users in Bangkok, Thailand

BACKGROUND

A large epidemic of HIV-1 subtype B began among injection drug users (IDUs) in Bangkok in 1988. Despite ongoing prevention efforts, HIV-1 prevalence among IDUs remained at 30-50% through the 1990s.

OBJECTIVES

To measure the incidence of HIV-1 infection and related risk factors to guide prevention efforts and to evaluate the feasibility of conducting an HIV vaccine efficacy trial.

DESIGN AND METHODS

A prospective cohort study in which IDUs attending methadone treatment programs in Bangkok were screened during 1995-1996 for enrollment into the study. IDUs found to be HIV-seronegative on two occasions were offered enrollment with follow-up visits every 4 months. On each visit participants were evaluated with a questionnaire and serologic testing.

RESULTS

A total of 1209 HIV-negative IDUs were enrolled. Through the end of 1998, the overall HIV-1 incidence rate was 5.8 (95% confidence interval, 4.8-6.8) per 100 person-years of follow-up. HIV-1 subtypes E and B accounted for 79 and 21% of infections, respectively. On multivariate analysis, HIV-1 seroconversion was primarily associated with the frequency of heroin injection, the sharing of injection equipment, and incarceration, especially with drug injection. Sexual behavior was not associated with increased risk for HIV-1. Risk factors for infection with HIV-1 subtypes E and B were similar.

CONCLUSION

HIV-1 transmission risk remains high among Bangkok IDUs despite methadone treatment and other current prevention strategies. There is an urgent need to address this ongoing epidemic, especially in jails and prisons. This study led to the initiation in 1999 of a phase III HIV-1 vaccine efficacy trial in this population.

Syringe availability as HIV prevention: a review of modalities

This review examines recent research into modalities for improving access to sterile syringes for injection drug users (IDUs) as a means to reduce human immunodeficiency virus (HIV) transmission. English language studies with empirical data were collected through Uncover reports and MedLine searches from 1998 to 2000. Although syringe-exchange programs are the most established and well-evaluated means of improving access to sterile syringes, research on alternative modalities-such as pharmacy sale, injector-specific packs, mass distribution, and vending machines-and on coverage of special populations suggests the need to pursue multiple avenues of increasing syringe availability simultaneously and, in particular, to explore modalities other than syringe-exchange programs when HIV incidence is under control. The impacts on HIV transmission of cocaine injection and sex with IDUs need to be explored further. Finally, any evidence of declining hepatitis C incidence among young IDUs might serve as a surrogate for a sharp drop in injection-related HIV risk behaviors in that population.

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.

AIDSVAX (MN) in Bangkok injecting drug users: a report on safety and immunogenicity, including macrophage-tropic virus neutralization

A randomized, double-blind, placebo-controlled phase I/II study of AIDSVAX (MN) was conducted among injecting drug users in Bangkok, Thailand. Four doses of vaccine (300 microg of MN-rgp120 in alum) or placebo (alum) were given at study entry and at 1, 6, and 12 months. The objectives of the study were to evaluate (1) the feasibility of conducting vaccine trials in this population; (2) the safety of this candidate AIDS vaccine; and (3) the immunogenicity of this vaccine. Thirty-three volunteers (22 vaccine and 11 placebo recipients) were recruited. None were lost to follow-up during the 18-month study. Mild reactogenicity was noted, which was similar in both vaccine and placebo recipients. The vaccine induced anti-HIV-1 antibody in all vaccine recipients. Maximal titers of binding antibodies of MN-rgp120 and the V3 domain of MN-rgp120 were induced after the third (6 month) dose while maximal neutralizing antibodies followed the fourth (12 month) dose. The vaccine-induced antibodies from several volunteers were capable of neutralizing macrophage-tropic, subtype B viruses (301660 and JRCSF) detected in a PBMC-based assay. Binding and neutralizing antibodies declined about 10-fold in the 6 months after the last boost. Two vaccinees became infected during the trial, both with subtype E viruses. A phase III efficacy trial, using a bivalent gp120 vaccine containing antigens from a subtype B virus (MN) and a subtype E virus (A244), was initiated in March 1999 in injecting drug users in Bangkok.

HIV monitoring in Vietnam: system, methodology, and results of sentinel surveillance

OBJECTIVE

To measure the prevalence of and trends in HIV infections in populations defined by sentinel surveillance in Vietnam.

METHODS

Surveillance was conducted in eight provinces in 1994, expanded to 12 in 1995 and to 20 in 1996. Sentinel populations were sexually transmitted disease (STD) patients, female sex workers (FSW), injecting drug users (IDU), tuberculosis (TB) patients, pregnant women, and military conscripts. Samples were collected twice yearly for high-risk populations and once yearly for low-risk populations.

RESULTS

The overall HIV epidemic in Vietnam comprises several different smaller epidemics. It is primarily associated with injecting drug use, but its extent varies widely throughout the country. In 1998, HIV prevalence rates ranged from 0 to 85% (median, 13.1%), with an aggregate prevalence rate (APR; i.e., the sum of HIV-positive study subjects divided by the sum of all study subjects tested in sentinel provinces) of 17% among IDUs; this ranged from 0 to 14.7% (median, 0.8%), with the APR of 2.4% among FSWs; and from 0 to 6% (median, 0%), with the APR of 0.9% among STD patients. The APRs among antenatal women and army conscripts were less than 0.15%. APRs increased significantly from 1994 to 1998 among STD patients (p < .001), FSWs (p < .001), TB patients (p < .001), and pregnant women (p < .05) in original sentinel provinces. HIV prevalence also increased significantly among younger age groups of IDUs and FSWs.

CONCLUSION

Vietnam's HIV epidemic is increasing predominantly and most rapidly among IDUs. However, prevalence rates among FSWs and STD patients are rising but are still low among pregnant women and army conscripts. Vietnam, at present, is still in the early phase of the HIV epidemic and has time to take effective and appropriate actions.

Audio-computer interviewing to measure risk behaviour for HIV among injecting drug users: a quasi-randomised trial

BACKGROUND

We aimed to assess audio-computer-assisted self-interviewing (audio-CASI) as a method of reducing under-reporting of HIV risk behaviour among injecting drug users.

METHODS

Injecting drug users were interviewed at syringe-exchange programmes in four US cities. Potential respondents were randomly selected from participants in the syringe exchanges, with weekly alternate assignment to either traditional face-to-face interviews or audio-CASI. The questionnaire included items on sociodemographic characteristics, drug use, and HIV risk behaviours for 30 days preceding the interview. We calculated odds ratios for the difference in reporting of HIV risk behaviours between interview methods.

FINDINGS

757 respondents were interviewed face-to-face, and 724 were interviewed by audio-CASI. More respondents reported HIV risk behaviours and other sensitive behaviours in audio-CASI than in face-to-face interviews (odds ratios for reporting of rented or bought used injection equipment in audio-CASI vs face-to-face interview 2.1 [95% CI 1.4-3.3] p=0.001; for injection with borrowed used injection equipment 1.5 [1.1-2.2] p=0.02; for renting or selling used equipment 2.3 [1.3-4.0] p=0.003).

INTERPRETATION

Although validation of these self-reported behaviours was not possible, we propose that audio-CASI enables substantially more complete reporting of HIV risk behaviour. More complete reporting might increase understanding of the dynamics of HIV transmission and make the assessment of HIV-prevention efforts easier.

Doing a shotgun: a drug use practice and its relationship to sexual behaviors and infection risk

There has been a rise in the frequency with which inhalational routes such as smoking are used for illicit drug use. A growing population of new inhalational drug users augments the pool of individuals at risk for transition to injection drug use. Further, illicit drug smoking has been implicated in the transmission of a variety of pathogens by the respiratory route, and crack smoking has been associated with an increased risk of HIV infection, particularly through the exchange of high-risk sex for drugs. Shotguns are an illicit drug smoking practice in which smoked drugs are exhaled or blown by one user into the mouth of another user. We conducted a series of ethnographic observations to attempt to characterize more fully the practice of shotgunning, the range of associated behaviors, and the settings and contexts in which this practice occurs. Shotguns may be seen as a form of drug use which has close ties to sexual behaviors, and which has both pragmatic and interpersonal motivations, combining in a single phenomenon the potential direct and indirect risk of disease transmission by sexual, blood borne and respiratory routes. These data support the need to develop and evaluate comprehensive risk reduction interventions, which take into consideration the relationships between interpersonal and sexual behaviors and specific forms of drug use.

The social ecology of syphilis

Factors affecting the transmission of syphilis can be categorized into those acting at the level of individuals (e.g., number of sex partners) and others at the level of the sociophysical environment (e.g., availability of treatment services for curable infections). In a prior study, we identified several sociophysical factors correlated with the ten-year mean syphilis rate in a regression analysis of United States counties. In the present study we used qualitative methods to investigate additional aspects of some factors in the regression, as well as to identify entirely new factors. Twelve counties with populations less than 100,000 and ten-year mean syphilis rates that were greater or less than expected by the regression model were selected for a three to five day visit. The case study protocol included observations, unstructured interviews with care providers and county residents, and a standardized questionnaire completed by state and local sexually transmitted disease control personnel pertaining to characteristics and practices of the local health department. Comparisons of the field notes and questionnaires revealed patterns of factors of the sociophysical environment that potentially affect county syphilis rates. These included access to the health department STD clinic, race relations, employment opportunities for minorities, interagency coordination, STD outreach activities, the social acceptability of discussing STDs, and intercommunity dynamics. In addition we noted the disproportionate influence of particular individuals on these factors. Some of the factors identified are readily quantifiable and could enhance the predictive power of multivariable models of county syphilis rates. The hypotheses generated by this study may also lead to a better measurement and understanding of potentially important environmental determinants of community syphilis rates, and the development of new or enhanced prevention strategies.

Infection with HIV-1 subtypes B and E in injecting drug users screened for enrollment into a prospective cohort in Bangkok, Thailand

From May through August 1995, a cross-sectional survey was conducted among injecting drug users (IDUs) drawn from 15 drug treatment clinics in Bangkok and who were not known to be HIV-seropositive, to determine the prevalence of HIV-1 subtypes B and E and related risk behaviors, and to offer enrollment in a prospective cohort study. IDUs who voluntarily consented were interviewed, and blood specimens were tested for the presence of HIV antibodies. HIV-1-seropositive specimens were tested for subtypes B' (Thai B) and E by using V3 loop peptide enzyme immunoassays specific for these HIV-1 genetic subtypes. Of 1674 IDUs studied, the mean age was 31.2 years (interquartile range, 25-37 years), 94.8% were men, and 29.3% were HIV-1-seropositive. On multiple logistic regression analysis, HIV-1 seropositivity was associated with older age, not being married, less education, needle sharing, and incarceration. HIV-1 subtype B' accounted for 65% of prevalent infections and subtype E, 35%. Infection with subtype E was associated with younger age and did not seem to be associated with sexual risk behaviors, which were uncommon in general. Bangkok IDUs continue to be at high risk for HIV-1 infection related to needle sharing and incarceration. Although HIV-1 subtype B' accounts for most prevalent infections, subtype E seems to be more prevalent among younger IDUs, and most infections seem likely to result from parenteral transmission.

Needle sharing and high-risk sexual behaviors among IV drug users in Southern Thailand

This study sought to determine the prevalence of needle sharing and high HIV risk sexual behaviors and to identify characteristics associated with these practices in southern Thailand. Data were obtained using a structured questionnaire from 298 male intravenous drug users (IVDUs) seen in a methadone clinic during the previous year. The prevalence of HIV was 37%, and that of needle-sharing in the preceding months was 45%, although only 10% claimed to have had unsafe sex with a casual partner or prostitute in the same period. Determinants for needle sharing included shorter duration of drug injection, diminished knowledge of HIV prevention, a carefree attitude toward risk of HIV infection, and lower levels of income. Young single IVDUs with a low knowledge of HIV prevention were most likely not to use a condom. In conclusion, needle sharing among the study subjects was still a common practice, whereas high HIV risk sexual behavior was not. Attitudinal change may be necessary to reduce needle-sharing behavior and not just information on disease transmission.

Harm reduction in the hills of northern Thailand

The human immunodeficiency virus (HIV) pandemic has swept through injecting drug user (IDU) communities around the world. Once HIV is present in an IDU community, seroprevalence rates escalate rapidly unless immediate and comprehensive prevention methods are put in place. Such measures often include providing IDUs with sterile injecting equipment and dispensing methadone or other opiate substitution formulas. These measures fall under the rubric of harm reduction-an attempt to reduce the harm to drug users, their families, and communities, including preventing or limiting the transmission of HIV and other blood-borne viruses. In Thailand, HIV-1 spread rapidly among IDUs with seroprevalence rates jumping from 1 to 40% in the space of a year. Current incidence rates are estimated at 11 per 100 person years. This paper describes the establishment and implementation of needle and syringe exchanges among injecting drug users in nine Hilltribe communities in Northern Thailand. The exchanges have been operating for between 1 and 3 years and have been effective in limiting the transmission of HIV within these small communities. The needle and syringe exchanges are run by indigenous staff with the cooperation of the community and provide a good example of the feasibility of establishing locally-run, community-based harm reduction programs.

Risk factors for HIV seropositivity in a sample of drug users in drug treatment in Ho Chi Minh City, Vietnam

The article describes drug use behaviors, AIDS knowledge, risks for HIV infection, and HIV seroprevalence in drug users entering rehabilitation in Ho Chi Minh City, Vietnam. A cross-sectional, descriptive survey of all new entrants to a residential drug treatment center was conducted with linked HIV serology between July 1 and July 14, 1995. A total of 105 subjects participated: 101 men and 4 women. HIV serostatus was available for 88 subjects. Forty-seven percent (41 of 88 subjects) were HIV-positive. Median age of the subjects was 38 years. Mean length of injection drug use was 13.2 years (range, 1-27 years). The primary drug of injection was opium (96%), although 59% of subjects also injected "Western" drugs such as sedatives or tranquilizers. Eighty-two percent (86 of 105 subjects) correctly answered at least 7 of 10 AIDS knowledge questions, and only 28% (27 of 97 subjects) reported any needle sharing in the last 5 years. Seropositivity was associated with a history of previous treatment for drug abuse (p = 0.002), longer history of injecting drugs (p = 0.003), use of Western drugs (p = 0.03), and higher educational level (p = 0.05). Multivariate analysis found that the independent predictors of HIV seropositivity were history of previous treatment for drug abuse (p = 0.06) and longer history of injecting drugs (p = 0.05). Despite low levels of self-reported needle sharing and high levels of AIDS knowledge, HIV seroprevalence was high in this sample. The potential for epidemic spread of HIV in Vietnamese drug users is substantial. Risk-reduction programs and intense AIDS education projects targeting the population of drug users are necessary to control the AIDS epidemic in Vietnam.

Impact of a longitudinal community HIV intervention targeting injecting drug users' stage of change for condom and bleach use

PURPOSE

To evaluate the impact of the Long Beach AIDS Community Demonstration Project, a community-based HIV-prevention intervention incorporating principles from the Transtheoretical model in its design and evaluation.

DESIGN

Repeated cross-sectional sampling with matched intervention and comparison communities.

SETTING

Neighborhoods in Long Beach, California, having a high prevalence of drug abuse and prostitution.

SUBJECTS

3081 injecting drug users who were sexually active and/or shared injection equipment.

INTERVENTION

Trained peer volunteers distributed fliers featuring role model stories targeted to the population's stage of change. Fliers were packaged with bleaching kits and/or condoms.

MEASURES

Primary outcome measures were exposure to the intervention, condom carrying, and stage of change for disinfecting injection equipment with bleach and for using condoms with main and other partners.

RESULTS

Toward the end of the study, 77% of injection drug users in the intervention area reported being exposed to the intervention. In the intervention area, rates of condom carrying increased from 10 to 27% (p < .001), and there was an increase from 2.32 to 3.11 in mean stage of change for using condoms with other partners, while stage of change decreased in the comparison area (p < .01). Mean stage of change for using condoms with a main partner also increased in the intervention area, but the difference was not significant after controlling for change in the comparison area. Subjects with recent project exposure had higher stage-of-change scores for using condoms with a main partner (p < .05) and other partners (p < .01) and for cleaning injection equipment with bleach (p < .05).

CONCLUSIONS

The results demonstrate the effectiveness of the AIDS Community Demonstration Project intervention for reaching injecting drug users in the community and for motivating the adoption of risk-reducing practices.

HIV infection risks, behaviors and methadone treatment: client-reported HIV infection in a follow-up study of injecting drug users in New England

There is wide variation in reported risk factors for HIV incidence among injecting drug users by community. Available HIV seroprevalence and incidence data indicate that nearly 60% of HIV infection is associated with injecting drug use in Connecticut and 48% in Massachusetts. Using 12-month follow-up data on 354 initially HIV-negative New England (Massachusetts and Connecticut) methadone treatment clients, we assessed the association between baseline drug use practices, sexual behavior, partner behaviors, and client-reported HIV infection during follow-up. Variables that predicted client-reported positive HIV antibody test results were modeled by Cox proportional hazards regression. HIV infection among those tested was 14.2 per 100 person years (PY) [95% Confidence interval (CI) = 9.5 to 21.3]. For each injection the relative risk (RR) was 1.1 (95% CI = 1.1 to 1.2), for males 3.0 (95% CI = 1.2 to 7.3), for blacks 5.0 (95% CI = 1.6 to 15.5), for Hispanics 3.6 (95% CI = 1.2 to 10.5). Men who used more than one unclean needle per day and had an HIV-infected steady partner had an RR of 28.4 (95% CI = 4.4 to 176.4). For women, using speedball (RR = 6.1, 95% CI = 1.2 to 38.8) and being black (RR = 4.4, 95% CI = 1.0 to 19.8) predicted self-reported HIV infection; having a steady partner who ever injected increased this risk substantially (RR = 65.3, 95% CI = 4.0 to 1046.5). These findings for IDUs in Massachusetts and Connecticut indicate that risk factors for HIV infection for men are consistent with expected transmission by unclean needles with an HIV-infected partner, but a preference for using speedball predicted HIV infection among women IDUs.

Changes in HIV/AIDS Risk Behaviors in Drug Users in St. Louis: Applications of Random Regression Models

A National Institute on Drug Abuse demonstration project in AIDS prevention among drug users was conducted in St. Louis during the years 1990 through 1994. The main objective was to reduce the spread of HIV by counseling drug users and by improving drug-treatment programs in the area. A second objective was to examine the correlates of risk behavior. A structured interview was administered six times over an 18-month period. Of those persons assessed at baseline (n = 475), 95.0% (n = 451) were also reinterviewed in the last interview at 18 months. Both group and individual level changes in risk behavior were assessed using random regression models. We report on three potential risk behaviors for HIV/AIDS: (1) number of sexual partners, (2) frequency of condom use, and (3) injection drug use. For each risk behavior a separate statistical model was estimated. The results of the random regression models showed significant reductions in number of sexual partners and injection drug use. Additionally, a number of variables, such as perceived risk for AIDS and knowledge of HIV/AIDS, were statistically significant covariates of risk behavior.

High HIV Seroprevalence Epidemics among Injecting Drug Users; New York City and Bangkok

New York City, U.S.A., and Bangkok, Thailand, experienced two of the most important HIV epidemics among injecting drug users (IDUs) in the world. The epidemic in New York was the first, and by far the largest, HIV epidemic among IDUs. The Bangkok epidemic was notable both for the rapidity of HIV transmission among IDUs and for demonstrating that HIV transmission could occur among IDUs in developing countries. Rapid HIV transmission among IDUs in both cities was followed by large-scale behavior change and stabilization of HIV seroprevalence at high levels. The stabilization of seroprevalence includes unacceptably high rates of continued HIV seroconversions—estimated to be 4 per 100 person-years at risk or greater in both cities. Recent additional HIV prevention efforts in both cities—long-term methadone maintenance treatment in Bangkok and legal access to sterile injection equipment in New York—indicate possibilities for father reducing HIV transmission among IDUs in the two cities.

The protective effect of AIDS-related behavioral change among injection drug users: a cross-national study. WHO Multi-Centre Study of AIDS and Injecting Drug Use

OBJECTIVE

This study assessed the relationship between self-reported acquired immunodeficiency syndrome (AIDS) behavioral change and human immunodeficiency virus (HIV) serostatus among injection drug users.

METHODS

The study sample involved 4419 injection drug users recruited from drug abuse treatment and nontreatment settings in 11 cities in North America, South America, Europe, Asia, and Australia. The World Health Organization multisite risk behavior questionnaire was used, and either blood or saliva samples for HIV testing were obtained. Subjects were asked, "Since you first heard about AIDS, have you done anything to avoid getting AIDS?"

RESULTS

The protective odds ratio for behavioral change against being infected with HIV was 0.50 (95% confidence interval = 0.42, 0.59). While there was important variation across sites, the relationship remained consistent across both demographic and drug use history subgroups.

CONCLUSIONS

Injection drug users are capable of modifying their HIV risk behaviors and reporting accurately on behavioral changes. These behavioral changes are associated with their avoidance of HIV infection.

Alcohol use and T-lymphocyte subsets among injection drug users with HIV-1 infection: a prospective analysis

OBJECTIVES

Alcohol use is known to alter immune function and has immunosuppressive effects that may modify T-lymphocyte subpopulations. However, there is no clear evidence regarding the relationship of alcohol use with the progression of immunodeficiency in human immunodeficiency virus-type 1 (HIV-1)-seropositive individuals, particularly injection drug users (IDUs).

METHODS

Using prospective data from a cohort of IDUs in a study of the natural history of HIV infection, we examined the relationship of alcohol use and changes in T-lymphocyte subsets. Among the 2921 IDUs followed semiannually in outpatient clinics, 188 were documented HIV-1 seroconverters with known time of seroconversion. At each visit, all study participants were interviewed, underwent physical examinations, and had blood drawn for laboratory studies. Alcohol use was measured by reported frequency and quantity of alcoholic beverages. Longitudinal analyses included data for up to 5 years postseroconversion. To formally test the association of alcohol use with change in levels of CD4+ and CD8+ cells subsequent to HIV seroconversion, regression models incorporating autocorrelation structure were applied.

RESULTS

Alcohol use was not appreciably related to age, gender, marital status, income, education, or the duration of intravenous drug use. CD4% decreased for all IDUs within the first 5 years after seroconversion, with no significant differences between alcohol categories. CD8% increased for all IDUs, with no significant differences by alcohol category within the first 2 years after seroconversion. However, between 2 to 5 years postseroconversion, there was a statistically significant increase among the heaviest drinkers: CD8% increased 6.9%/year [95% confidence interval (CI): 4.7, 8.0] for the IDUs who reported > 21 drinks/week, 2.4%/year (95% CI: 0.8, 4.0) for IDUs who drank 21 drinks/week or less, and 0.4% (95% CI: -2.1, 2.9) for abstainers. Similar results were obtained for CD4 and CD8 absolute counts.

CONCLUSIONS

In this study population of IDUs, CD8% (but not CD4%) is associated with alcohol consumption early after HIV seroconversion. This is the first prospective study to date to assess the relationship of alcohol use with HIV progression from the time of HIV seroconversion among a cohort of IDUs. If confirmed in future investigations, the findings may have significant implications for prevention and early intervention programs aimed at inhibiting disease progression among HIV-positive IDUs.

Validity of intravenous drug abusers' self-reported changes in HIV high-risk drug use behaviors

The HIV-1 high-risk drug use behavior of intravenous drug abusers was assessed both retrospectively (for 6 months) and prospectively (for 6 months) via structured interview and urinalysis testing. Subjects were 281 intravenous drug abusers, 146 enrolled in outpatient methadone treatment (Treatment group) and 135 not in treatment (Community group). The Treatment group reported fewer drug injections and less needle sharing and had fewer positive urinalyses for opiates and cocaine than did the Community group. Reported drug injection and needle sharing declined over time, and an increasing proportion of subjects reported abstinence from these behaviors. In contrast to the behavioral reports of subjects, positive urinalyses indicating opiate and/or cocaine use did not decline over time. Almost half (45.8%) of the reported increase in injection abstinence from intake to month six was disconfirmed by urinalysis. In contrast to this large discrepancy regarding reported behavior change, there was good agreement between reported injection abstinence and urinalysis results at single points in time. These data indicate that the validity of the reported HIV-1 risk behavior change of drug abusers may be less than that of reported risk behavior occurrence. The data raise important questions about the validity of reported reductions in high-risk drug use behaviors, and indicate the importance of using biological indicators of HIV-1 risk behavior (such as urinalysis) whenever possible.

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.

The 1993 Okey Memorial Lecture. Cross-national studies of AIDS among injecting drug users

HIV infection among injecting drug users has become a world-wide public health problem. This raises fundamental questions about the modifiability of drug-using behavior and of the influence of different national settings upon the modification of drug use behavior. Data from the World Health Organization Multi-site Study of HIV and Injecting Drug Use and studies of HIV among drug injectors in New York City (the US component of the WHO study) are used to address these questions. There is no clear relationship between HIV seroprevalence and current levels of risk behavior in the WHO cities, and the range in seroprevalence is much greater than the range in current risk behavior. Nonetheless, historical trend data enable us to discern at least two broad patterns in different cities. HIV epidemics appear to have been successfully prevented among IDUs in some cities, in that seroprevalence has remained low and stable over several years. These cities are characterized by community outreach programs and good access to sterile injection equipment. On the other hand, high seroprevalence epidemics have also occurred in many different cities. Stabilization of seroprevalence has eventually also occurred in these cities, but this still includes moderate rates of new HIV infections. How to reverse high-seroprevalence situations remains one of the more difficult questions in HIV epidemiology. The epidemiology of HIV infection among injecting drug users also needs to include analyses of the impacts of decisions by political and public health leaders. A three-category scheme for classifying political decisions is offered: data-free decisions, data-based decisions, and data-proof decisions.