Sexual behaviour of drug injectors in London: implications for HIV transmission and HIV prevention

History of intimate partner violence is associated with sex work but not sexually transmitted infection among HIV-positive female drinkers in Russia

This paper assesses the associations between intimate partner violence (IPV) and sexually transmitted infections (STIs) and sexual risks among HIV-positive female drinkers in St Petersburg, Russia. Survey and STI data were analysed from 285 women in HERMITAGE, a secondary prevention study of HIV-positive heavy drinkers. Logistic and Poisson regression analyses assessed associations of IPV with STI and risky sex. Most women (78%) experienced IPV and 19% were STI positive; 15% sold sex. IPV was not significantly associated with STI, but was with selling sex (adjusted odds ratio = 3.56, 95% confidence interval = 1.02-12.43). In conclusion, IPV is common and associated with sex trade involvement among Russian HIV-positive female drinkers.

'Where sex ends and emotions begin': love and HIV risk among female sex workers and their intimate, non-commercial partners along the Mexico-US border

This study explores the affective dimensions of female sex workers' relationships with their intimate, non-commercial partners and assesses how emotions shape each partner's sexual and drug-related risk within their relationship. We draw on qualitative data from a study of HIV, sexually transmitted infections and high-risk behaviours among female sex workers and their non-commercial partners in Tijuana and Ciudad Juárez, Mexico, to illustrate that these couples share relationships based on love, trust, respect and emotional and material support. These relationships range in emotional intensity, which shapes partners' decisions not to use condoms with each other. Drugs were important in most couples' relationships. Among injectors, syringe sharing was common and represented both a sign of care and a pragmatic reaction to conditions of material scarcity. Our findings suggest that couple-based HIV interventions to address dual sexual and drug-related risks should be tailored to the emotional dynamics of sex workers' intimate relationships.

Analysis of duration of risk behaviour for key populations: a literature review

Background

The objective of this paper is to review literature in order to calculate regional estimates of the average duration of time individuals maintain a specific high-risk behaviour.

Methods

The review targeted the key populations of female sex workers (FSW), male clients of female sex workers (MCFSW), people who inject drugs (injecting drug users (IDU)) and high-risk men who have sex with men (MSM). To be included in the review the study had to provide information on (1) the time a person spent at risk until death or cessation of the risk behaviour, (2) the percentage of the sample who initiated the risk behaviour in less than a year or (3) the mean or median duration of the behaviour from a representative sample.

Results

49 papers were found for the FSW population describing the period of time FSW stay in sex work to be between 2.9 years (Asia) and 12 years (Latin America). Eight papers were found for MCFSW showing the duration of the risk behaviour in this category varying from 4.6 years in Africa to 32 years in Asia. 86 papers were reviewed for the population of IDU showing that the average time a person injects illegal drugs varies from 5.6 years (Africa) to 21 years (South America). No information was found for duration of high-risk behaviour among MSM; instead, the definitions found in the literature for high- and low-risk behaviour among MSM were described.

Conclusions

There is high variability of estimates of duration of high-risk behaviours at regional level. More research is needed to inform models and prevention programmes on the average duration of time individuals maintain a specific high-risk behaviour.

Exploring the impact of underage sex work among female sex workers in two Mexico-US border cities

Although sex work and younger age increase HIV vulnerability, empirical data regarding the impacts of underage sex work are lacking. We explored associations between features of the risk environment, sex work, and drug use history, and underage sex work entry among 624 female sex workers (FSWs) in Tijuana and Ciudad Juarez, Mexico. Forty-one percent (n = 253) of women began sex work as minors, among whom HIV and any STI/HIV prevalence were 5.2 and 60.7%. Factors independently associated with increased odds of underage sex work were inhalants as the first drug used, forced first injection, number of drug treatment attempts, and recent receptive syringe sharing. Number of recent condom negotiation attempts with steady partners and depression as a reason for first injecting were negatively associated with underage entry. These results underscore the importance of efforts to prevent underage sex work and the wider factors contributing to HIV risk among vulnerable youth and underage FSWs.

The prevalence and incidence of sexually transmitted infections in a prospective cohort of injection drug users in Vancouver, British Columbia

BACKGROUND

While several studies have reported on sexual risk behaviours and the prevalence of sexually transmitted infections (STIs) among injection drug users (IDUs), there are fewer prospective studies that have been able to examine populations of IDUs with no history of STIs. Therefore, the authors examined prevalence, correlates and factors associated with time to first STI infection in a prospective cohort of IDUs in Vancouver, British Columbia.

METHODS

The authors examined the prevalence and correlates of STIs among IDUs at the time of recruitment into a prospective cohort study. The authors also evaluated the cumulative rate of time to first STI among IDUs with no history of STIs at baseline using the Kaplan-Meier method, and modelled factors independently associated with first STI using Cox regression.

RESULTS

Between May 1996 and November 2003, 1560 individuals were recruited into the cohort; of these individuals, 745 reported a history of STI at baseline. Among the 815 who did not report an STI at baseline, 671 (82%) had at least one follow-up visit and were eligible for the analysis of time to first STI. After 36 months of follow-up, the cumulative rate of first STI was 8.2% for men and 15.9% for women (log-rank P<0.001), whereas the cumulative rate of first STI was 8.0% for IDUs who did not report sex trade involvement versus 19.8% for IDUs who reported sex trade involvement (log-rank P<0.001). In multivariate analyses, the risk of first STI remained independently associated with unprotected sex with regular partners (relative hazard=2.04, 95% CI 1.29 to 3.23; P=0.001) and unprotected sex with sex trade clients (relative hazard=2.36, 95% CI 1.46 to 3.82; P=0.005).

CONCLUSIONS

In the present study, the authors found that STIs were associated with both regular sex partnerships and sex trade involvement. These findings are of particular concern because both unprotected sex with regular partners and sex trade involvement is common among IDUs. Interventions to encourage condom use among IDUs, particularly those with regular sex partners and those involved in the sex trade, should be further developed.

Hepatitis C virus among non-injecting cocaine users (NICUs) in South America: can injectors be a bridge?

AIM

To investigate the factors associated with hepatitis C virus (HCV) infection among non-injecting cocaine users (NICUs) and to compare practices associated with HCV and HIV infection.

DESIGN

An intercountry cross-sectional study. Setting  Buenos Aires and Montevideo metropolitan areas.

PARTICIPANTS

A total of 871 NICUs.

MEASUREMENTS

NICUs were interviewed and their blood was drawn and used for HCV, HIV, HBV surface antigen (HbsAg), HB-anticore and Venereal Disease Research Laboratory (VRDL) antibody assays. Bivariate and multivariate logistic regression analyses included comparisons of HCV and HIV mono-infected participants with HCV-HIV seronegatives.

FINDINGS

Prevalence rates were 8.8 [95% confidence interval (CI): 6.9-10.8) for HCV and 7.9 (95% CI: 6.1-9.7) for HIV. HCV-infected NICUs were twice as likely as HCV-HIV seronegatives to have shared straws for cocaine snorting or sniffing, even when adjusted for other variables. HCV prevalence rates ranged from 3.6% among NICUs who denied sharing straws and having had an injection drug user (IDU) or an HIV-positive sexual partner to 12.6% among participants who reported ever having shared straws or having had either an IDU- or HIV-positive sexual partner (χ(2) (trend)  = 6.56, P = 0.01).

CONCLUSIONS

Non-injecting cocaine users from South America are vulnerable to multiple infections and HCV infection appears to occur through the sharing of straws. HCV infection is associated with intimate relationships with IDUs or HIV-seropositive partners, supporting the hypothesis that HCV risk may be due primarily to risk-taking behaviour associated with drugs in this population.

Development of the Treatment Outcomes Profile

AIM

To develop the Treatment Outcomes Profile (TOP), a new instrument for monitoring substance misuse treatment.

DESIGN

Prospective cohort, psychometric evaluation with 7-day retest and 1-month follow-up to assess inter-rater reliability, concurrent, discriminant and construct validity, and change sensitivity.

PARTICIPANTS

A sample of 1021 service users, aged 16-62 years. Recruitment from 63 treatment agencies in England, collectively providing opioid substitution treatment, psychosocial interventions, in-patient detoxification and residential rehabilitation.

MEASUREMENTS

Thirty-eight frequency, rating scale and period prevalence measures, with 28-day recall, across substance use, health, crime and social functioning domains, administered as personal interview by 163 treatment keyworkers.

FINDINGS

Twenty outcome measures met inter-rater reliability criteria: days used alcohol, opioids, crack cocaine, cocaine powder, amphetamines, cannabis and one other named substance; days injected and period prevalence of direct or indirect needle/syringe sharing; subjective rating of physical and psychological health; days committed shop theft and drug selling, period prevalence of vehicle, property, fraud/forgery and assault/violence offences; rating of quality of life; days worked and attended for education/training; and period prevalence of acute housing problems and risk of eviction. Intraclass correlation coefficients for scale measures and Cohen's kappa for dichotomous measures reached or exceeded 0.75 and 0.61, respectively. There were satisfactory validity assessments and change sensitivity of scale items judged by effect size and smallest detectable difference. The TOP clinical tool contains an additional 10 items for individual treatment planning and review.

CONCLUSIONS

The TOP is a reliable and valid 20-item instrument for treatment outcomes monitoring.

Trends in hepatitis B virus, hepatitis C virus, and human immunodeficiency virus prevalence, risk behaviors, and preventive measures among Seattle injection drug users aged 18-30 years, 1994-2004

Injection drug users (IDUs) are at risk for infection with hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Information on time trends in prevalence of these viruses among IDUs and in behaviors influencing their transmission can help define the status of these epidemics and of public health efforts to control them. We conducted a secondary data analysis combining cross-sectional data from IDUs aged 18-30 years enrolled in four Seattle-area studies from 1994 to 2004. Participants in all four studies were tested for antibody to HIV (anti-HIV), hepatitis B core antigen (anti-HBc), and HCV (anti-HCV), and completed behavioral risk assessments. Logistic regression was used to investigate trends in prevalence over time after controlling for sociodemographic, drug use, and sexual behavior variables. Between 1994 and 2004, anti-HBc prevalence declined from 43 to 15% (p < 0.001), anti-HCV prevalence fell from 68 to 32% (p < 0.001) and anti-HIV prevalence remained constant at 2-3%. Declines in anti-HBc and anti-HCV prevalence were observed within the individual studies, although not all these declines were statistically significant. The declines in anti-HBc and anti-HCV prevalence remained significant after control for confounding. Although we did not observe coincident declines in injection equipment sharing practices, there were increases in self-reported needle-exchange use, condom use, and hepatitis B vaccination. We conclude that there has been a substantial and sustained reduction in prevalence rates for HBV and HCV infection among young Seattle IDUs, while HIV rates have remained low and stable.

Health trends among drug users attending needle exchange programmes in Switzerland (1994–2000)

As a part of an assessment of the Swiss drug harm-reduction policy, cross-sectional surveys were conducted in 1994, 1996 and 2000 among attenders of all needle exchange programmes (NEP) in Switzerland to assess changes in specific aspects of their health related to drug use. Data were gathered in each NEP over one week, using a questionnaire completed partly with an interviewer and partly self administered. The questionnaire covered socio-demographic characteristics, drug consumption, risk, prevention behaviour and state of health. Over a 6-year period (1994-2000), the average age of NEP attenders rose by 4 years. The prevalence of reported HIV remained fairly stable at around 10%. Reported level of Hepatitis C prevalence was high (59%). Incidence of used injection equipment sharing during the last 6 months was low and stable (9% in 1994, 12% in 2000); however, other forms of risk behaviour linked to intravenous drug use, such as sharing spoons, cotton or water, were more frequently reported. The HIV epidemic among NEP attenders seems to be contained, but this is not the case with Hepatitis C, and more attention should be paid to its prevention.

Impact of Gender and Sex Work on Sexual and Injecting Risk Behaviors and Their Association With HIV Positivity Among Injecting Drug Users in an HIV Epidemic in Togliatti City, Russian Federation

OBJECTIVES

Togliatti City is witness to a large epidemic of human immunodeficiency virus (HIV) associated with injecting drug use (IDU).

GOAL

This study sought to examine whether risk behaviors and risk factors associated with HIV differed across a sample IDUs by gender and sex work.

STUDY

A sample of IDU (n = 423) comprising female sex workers (SWs) (n = 66), non-sex workers (nonSWs) (n = 89) and men (n = 268) were recruited by field workers in community settings. Behavioral and HIV prevalence data were collected.

RESULTS

HIV prevalence did not differ across the groups ( approximately 56%), but gender adversely affected some risk factors. A comparison of risk behaviors indicated that SWs were more likely to engage in risky injecting behaviors than either men or nonSWs. They were also more likely to report a history of sexually transmitted infections.

CONCLUSIONS

IDUs involved in sex work and IDU nonSWs require specific and targeted interventions to facilitate safer injecting and sexual behaviors.

Prevalence of and factors associated with HIV-1 infection among drug users visiting treatment centers in Tehran, Iran

OBJECTIVES

This study was conducted to identify the prevalence of and potential risk factors for HIV-1 infection among drug users visiting drug treatment centers in Tehran, Iran.

DESIGN

Cross-sectional quantitative study.

METHODS

Between October 2003 and May 2004, drug users who visited three public drug treatment centers in Tehran were interviewed and information about their sociodemographics, drug use characteristics, incarceration history, sexual history, and HIV/AIDS knowledge and risk perception were collected. Specimens of oral mucosal transudate were then collected from participants to be tested for HIV-1 antibodies. Logistic regression analysis was conducted on the association between the demographic and behavioral factors with HIV-1 infection.

RESULTS

Overall, 611 (588 male and 23 female) drug users participated in the study. Among male injectors with HIV-1 prevalence of 15.2%, a history of shared injection inside prison [adjusted odds ratio (OR), 12.37; 95% confidence interval (CI), 2.94-51.97] was the main factor associated with HIV-1 infection. Among those who reported no history of injecting drug use, HIV-1 prevalence was 5.4%, and lack of condom use during sex was significantly associated with the infection (adjusted OR, 3.42; 95% CI, 1.25-9.36).

CONCLUSIONS

HIV-1 infection is already prevalent among drug users in Tehran, Iran and shared injection inside prison has been revealed to be a particular risk factor for HIV-1 infection among injecting drug users. Harm reduction programs which have been started in Iran should be urgently expanded particularly in correctional settings and strengthened by condom use promotion to prevent sexual acquisition or transmission of HIV-1 among drug users.

"Friendships are a big part of it": social relationships, social distance, and HIV risks

Social distance, or how close or distant individuals consider others, is an important influence on drug injectors' HIV risk behavior. Qualitative in-depth interviews with a vignette were employed with a sample of drug injectors in England to explore the influence of social distance on HIV risk behavior. Analysis of these data distinguish between close and distant relationships in sexual behavior in the community and in drug-injecting behavior inside prison. These findings help to expose the constituents of social distance in relation to drug injectors' perceptions of HIV risk, which are discussed throughout this paper.

Changes in condom use after HIV diagnosis

We investigated changes in condom use after HIV diagnosis. The study population comprised 78 asymptomatic HIV-infected subjects recruited from a clinic in Oslo, Norway, during 1988-92. In total, 240 follow-up visits were carried out. The response variable was repeated measurements of whether or not condoms were always used during anal/vaginal intercourse at follow-up. The explanatory variables were: time from HIV diagnosis to follow-up, exposure group (heterosexually infected, homosexual men, or infected through injecting drug use), time of HIV diagnosis (before 1987 or later), and history of condom use before HIV diagnosis. Random effects logistic regression analysis was used to study incremental changes in condom use, accommodating an unbalanced repeated measurement design. The use of condoms increased monotonously over time after HIV diagnosis in all exposure groups. Condom use was least likely among injecting drug users, subjects diagnosed before 1987 and subjects without a history of frequent condom use before HIV diagnosis.

Development and testing of an HIV-risk screening instrument for use in health care settings

OBJECTIVE

To develop and test a brief, reliable, and valid HIV-risk screening instrument for use in primary health care settings.

DESIGN

A two-phase study: (1) developing a self-administered HIV-risk screening instrument, and (2) testing it with a primary care population, including testing the effect of confidentiality on disclosure of HIV-risk behaviors.

SETTING

Phase 1: 3 types of sites (a blood donor center, a methadone clinic, and 2 STD clinics) representing low and high HIV-seroprevalence rates. Phase 2: 4 primary care sites.

PARTICIPANTS

Phase 1: 293 consecutively recruited participants. Phase 2: 459 randomly recruited primary care patients.

MAIN OUTCOME MEASURE

Phase 1: comparison of the responses of participants from low and high HIV-seroprevalence sites. Phase 2: primary care patients' rates of disclosure of HIV-risk behaviors and ratings of acceptability.

RESULTS

Phase 1: through examining item-confirmation rates, item-total correlations, and comparison of responses from low and high HIV-seroprevalence sites, we developed a final 10-item HIV-risk Screening Instrument (HSI) with an internal consistency coefficient of .73. Phase 2: 76% of primary care patients disclosed at least 1 risky behavior and 52% disclosed 2 or more risky behaviors. Patients were willing to disclose HIV-risk behaviors even knowing that their physician would see this information. Ninety-five percent of our patient participants were comfortable with the questions on the HSI, 78% felt it was important that their doctor know their answers, and 52% wished to discuss their answers with their physician.

CONCLUSION

Our brief, self-administered HSI is a reliable and valid measure. The HSI can be used in health care settings to identify individuals at risk for HIV and to initiate HIV testing, early care, and risk-reduction counseling, necessary goals for effective HIV prevention efforts.

HIV risk behaviour in Irish intravenous drug users

The aim of the study was to measure HIV prevalence and risk behaviour in 185 Irish Intravenous Drug Misusers. Information was obtained by application of a standardised WHO questionnaire covering HIV risk behaviour in the preceding 6 months. HIV serostatus was obtained by saliva/blood sample testing. One hundred and 3 (55.7 per cent) shared and 114 (61.6 per cent) lent used injecting equipment in the previous 6 months. 97 (94.2 per cent) of those who shared always cleaned the needles before use but only 48 (49.5 per cent) of these always cleaned in an efficient manner. One hundred and 14 (79.2 per cent) males and 28 (68.3 per cent) females reported heterosexual activity in the preceding 6 months. On examination sexual risk behaviour was found to be high. 50.5 per cent of males and 63 per cent of females never used condoms with regular partners. 32.6 per cent of males never used condoms with casual partners. The large majority of partners of male I.D.U'.s (both regular and casual) were non injectors. Therefore there is potential for sexual spread of HIV into the non-injecting heterosexual population. Conversely the vast majority of partners of female IDU's were injectors. This suggests that female IDU's are at higher risk of HIV infection than their male counterparts. HIV prevalence in the study group was 8.4 per cent. Implications of results for future intervention are discussed.

Prevalence of markers for hepatitis B virus and HIV-1 among drug injectors in London: injecting careers, positivity and risk behaviour

Concerns about the risks of HIV infection among drug injectors have eclipsed concerns about the prevalence and transmission of hepatitis, and in particular hepatitis B virus infection. Findings are reported from surveys undertaken with two separate community-recruited samples of drug injectors in London collected in 1992 (n = 505) and in 1993 (n = 507). Anonymized confirmed testing of saliva shows 51.5% of drug injectors in 1992 and 47.9% in 1993 to be antibody positive to the core antigen of hepatitis B virus (anti-HBc). Approximately half of the drug injectors confirmed as anti-HBc positive were unaware that they had been infected with hepatitis. Anti-HIV-1 prevalence was considerably lower at 7.0% in 1992 and 6.9% in 1993. Multivariate analyses showed anti-HBc positivity to be most likely among older injectors with longer injecting careers who had a history of having shared used needles and syringes. HIV-1 positivity was also associated with a history of having shared injecting equipment as well as with recent sharing (i.e. in the last 6 months). Unlike anti-HBc positivity, there were no associations between HIV-1 positivity and age or length of injecting career. Younger injectors with shorter injecting careers were more likely to report recent sharing of used injecting equipment than older injectors with longer injecting careers. We note the potential for continued transmission of HBV and HIV-1, particularly among younger injectors. We recommend an integrated strategy to maximize the health of drug injectors, of which HIV and HBV prevention is a part. There is a need to widen the availability of HBV vaccinations for HBV negative drug injectors and their sexual partners and for clear guidelines to drug injectors about the relative efficacy of bleach to disinfect injecting equipment of HBV and HIV.

Sex, drugs, intervention, and research: from the individual to the social

Epidemiological estimates of the sexual risk behavior of drug users have provided essential indicators to the current and future prevalence of HIV transmission. An overview of recent research shows the majority of drug injectors to be sexually active, low levels of reported condom use, a significant minority of female injectors to be involved in prostitution, relatively high levels of sexual mixing between drug injectors and noninjectors, and only scant indications of sexual behavior change. Epidemiological studies of risk, however, are unable to yield the data required to understand the interaction between individual risk behavior and social relationships. This is required if obstacles to safer sex compliance and sexual behavior change are to be overcome, and demands recognition of the influence and importance of social context on the production of sexual risk behavior in future research and intervention designs. In response, the paper explores the future role of qualitative research in understanding the social relations of "risk" and in contributing toward theoretical advancements in explanations of risk perception and risk behavior. The paper concludes by discussing the implications of this analysis for developing interventions which aim to target social relationships as agents of social network and community change.

[Drug users outside medical treatment: methodological and practical aspects]

A legal context that classifies the consumption of heroin and cocaine as an illegal act, poses a considerable methodological challenge to research on users of these substances. This is in particular the case for research on those users who are not in treatment and, therefore, cannot be recruited through treatment settings. In a research project on heroin and/or cocaine users outside treatment settings, a sample of 917 individuals was recruited through "Privileged Access Interviewers" in the whole of Switzerland. In the first part of this article, we discuss matters of reliability as well as of validity concerning this method of data collection. In the second part of the article, we discuss the use of low threshold syringe exchange schemes by the user groups represented in the sample. Only intravenous drug users frequent those services - they are however a minority in the sample (n = 238). In several regions of Switzerland syringe exchange schemes do not exist. Where they do exist, they appear to correspond to a need which they are able to cover largely. In the regions without such services, intravenous drug users get their supply of syringes more frequently from pharmacies. However, pharmacies do not compensate the absence of specific syringe exchange schemes. In regions without such schemes, injections with used syringes are more frequent. Thus, regarding Aids-Prevention, there is an urgent need to develop syringe exchange schemes in all parts of the country.

A brief survey of the current sexual practices of a population admitted for inpatient treatment of drug dependence

We studied a population of high-risk drug users concerning their current sexual practices. They had a pattern of inconsistent or infrequent condom use. Only 11.5% reported always using condoms; 38.2% reported never using them; and 50.3% reported using them sometimes. Experimental educational programs have demonstrated the feasibility of changing sexual behaviors in illicit drug users by using innovative techniques targeted specifically at them. The application of sex and marital therapy techniques to changing high-risk behaviors is not widely discussed in the substance abuse literature. The hypothesis that the application of the techniques of sex and marital therapy in educational programs for drug users will improve outcomes of HIV prevention should be tested.

AIDS and injecting drug use in the United Kingdom, 1987-1993: the policy response and the prevention of the epidemic

This paper assesses policy development, service changes and trends in HIV infection and risk behavior among injecting drug users (IDUs) in the United Kingdom. In 1986, the U.K. was faced with the possible rapid spread of HIV infection among IDUs. The combination of an outbreak of HIV infection with prevalence levels of 50% or more in Edinburgh, the recent diffusion of drug injecting, and high levels of syringe-sharing risk behaviour, suggested that HIV infection might spread rapidly through IDU populations. HIV prevention activities commenced in 1986 and developed in 1987. The first report on AIDS and Drugs Misuse by the Advisory Council on the Misuse of Drugs in 1988 was a major catalyst for change. It supported and legitimized emergent views on new ways of working with drug users. Between 1988 and 1993 innovative public health projects increased the ability to target vulnerable populations through syringe distribution, expansion of methadone treatment and outreach to hard-to-reach populations. There were major changes in service philosophy and practices, as ideas of harm minimization, accessibility, flexibility and multiple and intermediate goals were developed. There is evidence that these public health projects encouraged extensive changes in the health behaviour of IDUs. There have been major reductions in syringe-sharing risk behaviour and sharing syringes is no longer the norm. Evaluation of specific interventions (e.g. syringe-exchange) shows their importance in encouraging reductions in risk behaviour. Levels of HIV infection in IDUs remain low by international standards. Outside of London rates of about 1% have been reported; London has a low and declining prevalence of infection to around 7% in 1993; previous high levels in Edinburgh (55%) have since declined to 20%. Britain has to date avoided the rapid increase in HIV infection among injectors that has occurred in many parts of the world. The same period saw the continuation of high prevalence levels in New York and many European cities, and the explosive spread of HIV in many countries in south-east Asia. This paper acknowledges the difficulties is proving links between social interventions and epidemic prevention. It argues that there is prima facie evidence for the success of public health prevention, that the collection of intervention approaches in the U.K. had a significant impact on IDUs behaviour, and that this has helped prevent an epidemic of HIV infection among IDUs. The U.K. experience adds to the growing evidence of the significance of early interventions in encouraging behaviour change and in limiting the spread of HIV infection.

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.