HIV-positive Injection Drug Users Research Articles

Predictors of Sharing Injection Equipment by HIV-Seropositive Injection Drug Users

Among HIV-positive injection drug users (IDUs), we examined baseline predictors of lending needles and syringes and sharing cookers, cotton, and rinse water in the prior 3 months at follow-up. Participants were enrolled in Intervention for Seropositive Injectors-Research and Evaluation, a secondary prevention intervention for sexually active HIV-positive IDUs in 4 US cities during 2001-2005. The analyses involved 357 participants who reported injecting drugs in the prior 6 months at either the 6- or 12-month follow-up visit. About half (49%) reported at least 1 sharing episode. In adjusted analyses, peer norms supporting safer injection practices and having primary HIV medical care visits in the prior 6 months were associated with reporting no sharing of injection equipment. Higher levels of psychological distress were associated with a greater likelihood of reporting drug paraphernalia sharing. These findings suggest that intervention approaches for reducing HIV-seropositive IDUs' transmission of blood-borne infections should include peer-focused interventions to alter norms of drug paraphernalia sharing and promoting primary HIV care and mental health services.

Efecto de diferentes variables sociodemográficas en la progresión de la infección por el virus de la inmunodeficiencia humana en una cohorte de usuarios de drogas

ObjectiveTo analyze whether the effectiveness of combined antiretroviral therapy in delaying progression to AIDS and death is affected by social inequities in a cohort of HIV-positive injecting drug users (IDUs). MethodsA cohort of 3,122 HIV-positive IDUs identified in the AIDS Information and Prevention Centers of the autonomous region of Valencia was analyzed, with further follow-up in 1,876. Progression to AIDS and death after seroconversion were calculated by Kaplan-Meier estimation according to sociodemographic variables (age, sex, education, marital status, length of addiction). Cox regression models were also fitted. ResultsNo significant differences were observed according to the variables considered when analyzing time to AIDS development. Evaluation of survival time revealed that individuals with further follow-up showed an excess of mortality (HR = 1.35; 95%CI: 0.20-1.54). For individuals without follow-up, mortality risk was reduced in those with secondary school education (HR = 0.51; 95%CI: 0.35-0.74) and with university education (HR = 0.41; 95%CI: 0.18-0.93) compared with those with no education. When individuals with follow-up were analyzed, the differences lost significance for those with secondary school education (HR = 0.92; 95%CI: 0.72-1.19) and university education (HR = 0.62; 95%CI: 0.35-1.11). ConclusionsThe mortality excess found in IDUs with lower educational levels, especially among those not seeking healthcare in the initial period after being identified as HIV-positive, highlights the need for interventions aimed at facilitating access to health systems, especially among the socially disadvantaged.

The effects of low literacy and cognitive impairment on medication adherence in HIV-positive injecting drug users

Low literacy and cognitive impairment have each been separately identified as risks for non-adherence in HIV infection. However, no studies to date have evaluated these skill deficits in combination. We therefore characterized the nature of literacy and cognitive skills in a sample of HIV-positive injecting drug users and assessed their combined effects on adherence. A community-recruited sample of 57 HIV-positive injecting drug users completed the study. Participants were classified into one of four groups based on their performance on a reading test and a brief neuropsychological battery: high literacy/high cognition, low literacy/high cognition, high literacy/low cognition and low literacy/low cognition. Chi-square and bivariate analyses were used to characterize the literacy and cognitive skills of the overall sample and logistic regression analysis was used to test the relation of the four groups to non-adherence (< 95%). In general, performance on measures of literacy and cognitive functioning were below average, with severe deficits noted in psychomotor functioning. Additionally, after adjusting for recent cocaine use, those classified as low literate/low cognition were over nine times more likely to be non-adherent than the referent high literate/high cognition group. Low literacy and cognitive impairment placed HIV-positive drug users at high risk for non-adherence, even after adjusting for recent cocaine use. The findings suggest that targeted interventions to improve these skill deficits in this population may help to improve adherence to HIV medications.

High Prevalence of HIV, HIV/Hepatitis C Virus Coinfection, and Risk Behaviors Among Injection Drug Users in Chennai, India: A Cause for Concern

To estimate the prevalence of HIV and hepatitis C virus (HCV) and hepatitis B virus (HBV) coinfections and current risk behaviors among HIV-positive and -negative injection drug users (IDUs) in Chennai, India. Cross-sectional analysis of a convenience sample of 912 IDUs recruited between March 2004 and April 2005. Specimens were tested for HIV, HBV, and HCV. Adjusted prevalence ratios (PRs) were estimated using Poisson regression with robust variance estimates. The prevalence of HIV, hepatitis B surface antigen, and anti-HCV were 29.8%, 11.1%, and 62.1%, respectively. Among HIV-infected IDUs, prevalence of coinfection with anti-HCV and hepatitis B surface antigen/anti-HCV were 86% and 9.2%, respectively. In multivariate analysis, injecting at a dealer's place (PR: 1.57) and duration of injection drug use >or=11 years (PR: 3.02) were positively associated with prevalent HIV infection. Contrastingly, alcohol consumption >or=1 per week (PR: 0.55) was negatively associated with HIV. HIV-positive IDUs were as or more likely compared with HIV-negative IDUs to report recent high-risk injection-related behaviors. There is a high burden of HIV, HCV, and HBV among IDUs that needs to be addressed by improving access to therapies for these infections; furthermore, preventive measures are urgently needed to prevent further spread of HIV, HBV, and HCV in this vulnerable population.

Bangladesh Moves from Being a Low-Prevalence Nation for Hiv to One with a Concentrated Epidemic in Injecting Drug Users

Bangladesh has been conducting annual serological surveillance for HIV and syphilis since 1998 among most at-risk populations including sex workers, males having sex with males, injecting drug users (IDUs) and heroin smokers. During the seventh round conducted between January and June 2006, 10,368 people were sampled and the overall HIV prevalence was 0.9%. The highest HIV rate was recorded in male IDUs from the capital city Dhaka (7%), and the rates have risen significantly over the rounds (P < 0.001). In Dhaka, most of the HIV-positive IDUs (10.5%) were localized in one neighbourhood, while in the remaining neighbourhoods 1% were positive (P < 0.001). In all other groups, HIV prevalence was <1%. Active syphilis rates were highest in female IDUs (9.9%) followed by female street-based sex workers (8.6%). However, rates in female sex workers in Dhaka declined significantly over the years (P < 0.001). Bangladesh has to act urgently to prevent escalation of the epidemic.

Attitudes toward needle-sharing and HIV transmission risk behavior among HIV+ injection drug users in clinical care

Risky behavior related to injection drug use accounts for a considerable proportion of incident HIV infection in the United States. Large numbers of injection drug users (IDUs) currently receive antiretroviral therapy in clinical settings and are accessible for risk-reduction interventions to reduce transmission of drug-resistant HIV and spread of HIV to uninfected others. The current study examined attitudes toward needle- or equipment-sharing among 123 HIV-positive IDUs in clinical care in an effort to understand the dynamics of such behavior and to create a basis for clinic-based risk-reduction interventions. Results indicate that at baseline, participants who reported extremely negative attitudes toward needle-sharing were less likely to have shared during the past month than those with less-extreme negative attitudes. Demographic, behavioral, and attitudinal variables were entered into a logistic regression model to examine needle-sharing group membership among HIV-positive IDUs. Being female and having less-extreme negative attitudes toward sharing were independent and significant correlates of sharing behavior. Interventions targeting needle-sharing attitudes deployed within the clinical care setting may be well-positioned to reduce HIV transmission among HIV-positive IDUs.

Healthcare and antiretroviral treatment in HIV-infected detained persons at the penitentiary units

Summary There has been an increase rate of HIV prevalence among prison population in Poland. The prevalence of HIV infection in Polish prisons is 1,54 percent out of detained population. Total number of HIV/AIDS was 1145 prisoners in 2007, and 81 new cases was detected during imprisoning. HIV-positive injection drug users (IDU's) are a special category of patients whose access to treatment is limited by economic and addiction barriers, out of the prison walls. Recent studies in Central and Eastern Europe show that even with the wide availability of antiretroviral (ARV) medications, only 40 percent of IDU's received HAART. The situation is more alarming in Russia and other fSU, where less than 1 percent of HIV-positive drug users receiving ARV treatment. In Poland HIV-infected prisoners have been regularly monitored on the specialist visits, and they could voluntarily opt out of HIV tested, as well as HCV, HBV, syphilis, etc. Design of antiretroviral regimen in prison can be arrange precisely for long-term period. Directly administrated antiretroviral therapy is the best method for non-adherent patients, especially for IDU's in prison.

Are Feelings of Responsibility to Limit the Sexual Transmission of HIV Associated With Safer Sex Among HIV-Positive Injection Drug Users?

We developed a scale among HIV-positive injection drug users (IDUs) to measure self-perceived responsibility to limit HIV transmission during sex. We describe the characteristics of HIV-positive IDUs (n=1114, 62% male, HIV-positive for 9 years on average) who felt responsible for protecting their sexual partners from HIV and evaluated whether such feelings were associated with safer sexual practices. Using this scale (Cronbach alpha=0.83) and audio computer-assisted self-interviewing technology, 75% of this sample felt responsible for protecting their sexual partners from HIV. In cross-sectional multivariate analysis, HIV-positive IDUs who felt responsible were those with greater HIV knowledge (adjusted odds ratio [95% confidence interval]: 1.74 [1.26 to 2.40]), perceived social support (1.77 [1.28 to 2.44]), self-efficacy for safely injecting (1.41 [1.02 to 1.94]), and self-efficacy for using condoms (1.92 [1.38 to 2.68]). Feeling responsible was associated with having relatively fewer sex partners (<10 vs. >or=10, 0.57 [0.34 to 0.96]) and a lower odds of unprotected sex (0.63 [0.45 to 0.89]) but was not associated with safer injection practices. Feelings of responsibility did not vary by demographic characteristics, suggesting that prevention messages that encourage HIV-positive people to play a role in curbing HIV transmission may be acceptable to many HIV-positive IDUs. Working with HIV-positive IDUs to increase or reinforce feelings of responsibility may reduce the sexual transmission of HIV.

Correlates of Depression Among HIV-Positive Women and Men Who Inject Drugs

Although depression is common among HIV-positive injection drug users (IDUs), little is known about differences between male and female HIV-positive IDUs. We used baseline data for 1126 HIV-positive IDUs from a behavioral intervention trial from 2001 through 2005 in 4 US cities. Using the Brief Symptom Inventory-18, scores indicating high risk for depression were calculated separately for men and women based on raw scores of 9 for women and 7 for men. We did separate logistic regressions for men and women to evaluate correlates of depression in 4 domains: sociodemographic, psychosocial, substance use, and sexual behaviors/attitudes. Approximately one third of women and men met the criteria for being at high risk of depression. Women reported significantly more depressive symptoms than men. Correlates linked with depression for both genders included perceived functional limitation, greater negative feelings regarding condom use, lower social support, and lower sense of empowerment. Being physically abused as adults and being Hispanic were correlates specific to men. No unique correlate was identified for women. Because of the high prevalence of depression among HIV-positive IDUs, caregivers should screen HIV-positive IDUs for depression and consider treatment for depression. Because of the similarities in correlates of depression among men and women, case finding and interventions for depression are likely to be similar for male and female HIV-positive IDUs.

Correlates of Lending Needles/Syringes Among HIV-Seropositive Injection Drug Users

Among HIV-positive injection drug users (IDUs), we examined the correlates of lending needles/syringes with HIV-negative and unknown status injection partners. HIV-positive IDUs (N=738) from 4 cities in the United States who reported injection drug use with other IDUs in the past 3 months participated in an audio computer-assisted self-administered interview. Eighteen percent of study participants self-reported having lent their needles to HIV-negative or unknown status injection partners. Multivariate analyses showed that 6 variables were significantly associated with this high-risk injecting practice. Older IDUs, high school graduates, and those reporting more supportive peer norms for safer drug use were less likely to lend needles/syringes. Admission to a hospital for drug treatment in the past 6 months, having injected with >1 person in the past 3 months, and having more psychiatric symptoms were all associated with more risk. These findings underscore the need for a continued prevention focus on HIV-positive IDUs that recognizes the combination of drug use, mental health factors, and social factors that might affect this high-risk injecting practice, which could be associated with HIV and hepatitis C transmission.

Intimate Partner Violence Perpetration Against Main Female Partners Among HIV-Positive Male Injection Drug Users

Intimate partner violence (IPV) against women is a serious public health and social problem and is associated with a host of adverse health outcomes and behaviors, HIV risk behaviors included, among women who are victimized. Historically, research has focused on correlates of IPV victimization among women; thus, there is less information on the role of men in perpetrating IPV, particularly among men at risk for transmitting HIV to their female partners. We assessed the self-reported prevalence and correlates of perpetration and threat of perpetration of physical and/or sexual IPV against a main female partner among 317 HIV-positive men who were current injection drug users (IDUs). More than 40% of men reported perpetrating physical (39%) and/or sexual (4%) violence against their main female partners in the past year. Multivariate analyses revealed that low education, homelessness, psychologic distress, and unprotected sex with main and nonmain HIV-negative female partners were positively associated with IPV perpetration against main female partners. These findings reveal that IPV perpetration is prevalent among HIV-positive male IDUs and associated with sexual HIV transmission risk behaviors. IPV assessment and treatment among HIV-positive men in HIV care is recommended as a way to prevent IPV perpetration and victimization and to reduce potential HIV transmission.

Participants' Descriptions of Social Support Within a Multisite Intervention for HIV-Seropositive Injection Drug Users (INSPIRE)

HIV-positive injection drug users (IDUs) are at risk for transmitting HIV to their sex and injection partners, and compared with non-IDUs, they have poorer access to medical care and adherence to antiretroviral therapies. Social support has been linked with decreased injection and sexual risk behaviors and slower disease progression. In this qualitative process evaluation, we explored emotional support (ie, caring, empathy), informational support (ie, information, guidance, feedback), and appraisal support (ie, information for self-evaluation or understanding) received by participants in the Interventions for Seropositive Injectors-Research and Evaluation (INSPIRE) project, a multisite secondary prevention intervention for HIV-positive IDUs. Participants in the intervention and control conditions (N=40) described similar experiences in terms of type, source, and perceived benefits of social support received from the program. Emotional support was received from program staff, other participants, and elements of the intervention. Participants also mentioned social support received from the INSPIRE project in relation to changes they had made in their lives during and after their involvement in the intervention, such as changes in their drug use, sexual practices, and health care utilization.

Results From a Randomized Controlled Trial of a Peer-Mentoring Intervention to Reduce HIV Transmission and Increase Access to Care and Adherence to HIV Medications Among HIV-Seropositive Injection Drug Users

There is a lack of effective behavioral interventions for HIV-positive injection drug users (IDUs). We sought to evaluate the efficacy of an intervention to reduce sexual and injection transmission risk behaviors and to increase utilization of medical care and adherence to HIV medications among this population. HIV-positive IDUs (n=966) recruited in 4 US cities were randomly assigned to a 10-session peer mentoring intervention or to an 8-session video discussion intervention (control condition). Participants completed audio computer-assisted self-interviews and had their blood drawn to measure CD4 cell count and viral load at baseline and at 3-month (no blood), 6-month, and 12-month follow-ups. Overall retention rates for randomized participants were 87%, 83%, and 85% at 3, 6, and 12 months, respectively. Participants in both conditions reported significant reductions from baseline in injection and sexual transmission risk behaviors, but there were no significant differences between conditions. Participants in both conditions reported no change in medical care and adherence, and there were no significant differences between conditions. Both interventions led to decreases in risk behaviors but no changes in medical outcomes. The characteristics of the trial that may have contributed to these results are examined, and directions for future research are identified.

Sexual Transmission Risk Behavior Reported Among Behaviorally Bisexual HIV-Positive Injection Drug-Using Men

Few research studies have examined the HIV transmission risk behaviors of HIV-positive injection drug users (IDUs) who are men who have sex with men and women (MSMW). We compared unprotected vaginal or anal sex with an HIV-negative or unknown (UNK) status sexual partner of MSMW (n=118) with men who have sex exclusively with women (MSW; n=469) and men who have sex exclusively with men (MSM; n=90) using baseline information from the Intervention for Seropositive Injectors-Research and Evaluation (INSPIRE) study, a 4-city randomized controlled trial. MSMW were twice as likely to report unprotected vaginal sex (P<0.001) and 3 times as likely to report unprotected anal sex with an HIV-negative/UNK status female partner (P<0.001) as MSW. MSMW did not differ in their report of unprotected insertive anal sex and were half as likely to report unprotected receptive anal sex with HIV-negative/UNK status men (P=0.02) as MSM. MSMW were 2 times as likely to report engaging in transactional sex (buying or selling sex in exchange for money, drugs, or housing) than MSM or MSW (81%, 43%, and 36%, respectively; P<0.001). Further research is needed to understand the contexts of unprotected sex among HIV-positive injection drug-using MSMW. Prevention programs should target the unique prevention needs of this population, particularly their risk with female partners.

Recognition of Hepatitis C Virus Coinfection in HIV-Positive Injecting Drug Users in Asia

HIV and hepatitis C (HCV) are readily transmitted by the sharing of injecting equipment. It has been estimated that there are 2 to 9 million injecting drug users (IDUs) in the Asia Pacific region of whom approximately 750000 are living with HIV. Injecting drug use is a major mode of HIV transmission in many Asian countries accounting for more than 30% of infections in Myanmar; 40% in China; and most infections in Vietnam Indonesia and Malaysia. This is superimposed on a geographically varied high population prevalence of HCV. Prevalence across Asia can be explained by unsterile medical injections contaminated transfusions traditional cultural practices6 and more recently injecting drug use. There are few studies on the prevalence of HCV and HIV coinfection in Asia although all demonstrate almost universal HCV infection in HIV-infected IDUs. Increasing coinfection as a proportion of HIV infections in some countries indicates that although sexual transmission of HIV may be reducing transmission through sharing injecting equipment continues. A Thai study found that although the prevalence of HIV in military recruits (a marker of population HIV prevalence) decreased from 2.4% to 1.1% between 1995 and 2000 the proportion coinfected increased from 20.8% to 49.5% during the same period. (excerpt)

Beliefs that Condoms Reduce Sexual Pleasure—Gender Differences in Correlates Among Heterosexual HIV-Positive Injection Drug Users (IDUs)

Studies consistently find that negative condom beliefs or attitudes are significantly associated with less condom use in various populations, including HIV-positive injection drug users (IDUs). As part of efforts to reduce sexual risk among HIV-positive IDUs, one of the goals of HIV interventions should be the promotion of positive condom beliefs. In this paper we sought to identify the correlates of negative condom beliefs and examined whether such correlates varied by gender, using a subsample (those with an opposite-sex main partner; n = 348) of baseline data collected as part of a randomized controlled study of HIV-positive IDUs. In multivariate analyses, we found more significant correlates for women than for men. With men, perception that their sex partner is not supportive of condom use (negative partner norm) was the only significant correlate (Beta = -0.30; p < 0.01; R (2) = 0.18). Among women, negative partner norm (Beta = -0.18; p < 0.05); having less knowledge about HIV, STD, and hepatitis (Beta = -0.16; p < 0.05); lower self-efficacy for using a condom (Beta = -0.40; p < 0.01); and more episodes of partner violence (Beta = 0.15; p < 0.05) were significantly associated with negative condom beliefs (R (2) = 0.36). These findings suggest important gender-specific factors to consider in interventions that seek to promote positive condom beliefs among HIV-positive IDUs.

Sexually Transmitted Infections and Sexual Practices in Injection Drug Users and Their Regular Sex Partners in Chennai, India

Measuring sexually transmitted infections (STIs) and sexual practices in injection drug users (IDUs) and their regular sex partners. Informing HIV intervention programs. Cross-sectional. One percent IDUs and 2% of their regular female sex partners were syphilis infected; 40% (84/211) and 38% respectively (81/211) were infected with HSV-2. 30% IDUs and 5% of their female regular sex partners were HIV positive. Serodiscordant results for syphilis and HSV-2 were noticed. Women having first sex at age<or=17 years and those who had HIV-positive IDUs as their male sexual partner had two times the odds of having any non-HIV-STI (OR 2.04; 95% CI 1.1-3.8; P=0.02 and OR 2.38; 95% CI 1.1-5.1; P=0.02 respectively) in a multivariate model. Women>or=38 years had seven times the odds of having any non-HIV-STI. Reaching out to IDUs and their female regular sex partners with modified STI management guideline and promoting women-controlled safer sex measures are needed harm-reduction measures.

HIV outbreak among injecting drug users in the Helsinki region: social and geographical pockets

Incidence of newly diagnosed HIV infections among injecting drug users (IDUs) in Helsinki rose from 0 per 100,000 inhabitants in 1997 to 2.9 in 1998 and to 11.1 in 1999. Thereafter incidence declined to 2.1 in 2003. Data were collected from interviews with HIV-positive IDUs who attended the University Hospital in Helsinki from 1998 until 2003. We studied the sociodemographic profile and spatial distribution of IDUs who were diagnosed in the beginning of the outbreak and those diagnosed later. The indicator for the spatial differentiation within the metropolitan area is % employed males aged 25-64. The outbreak occurred among a marginalized population of IDUs characterized by a long history of injecting drug use (10.7 years), mean age 32 years, homelessness (66.3%), history of imprisonment (74.7%) and psychiatric hospital care (40.6%). Compared with 98 early cases diagnosed during the first 2 years until 2000, 47 recent cases diagnosed after 2001 were 4 years older, and as marginalized. Except for the city centre, both early and recent cases had been living or using drugs in the same deprived neighbourhoods with the highest unemployment rates. Up to 40% of cases in the two big geographical clusters did not have contact with the city centre, where the needle exchange services were available. The Finnish HIV outbreak is restricted socially to a very marginalized IDU population, and spatially to local pockets of poverty. In low prevalence countries, prevention programs should be targeted early at high-risk areas and populations.

First Molecular Surveillance Report of HIV Type 1 in Injecting Drug Users And Female Sex Workers along The U.S.–Mexico Border

HIV prevalence is increasing among high-risk populations in the Mexican-U.S. border cities of Tijuana and Ciudad Juarez. In 2005, the molecular epidemiology of HIV-1 was studied among injecting drug users (IDU) and female sex workers (FSW) in these cities, which are corridors for over two-thirds of the migrant flow between Mexico and the United States. Eleven samples (eight IDU and three FSW) were successfully amplified, sequenced, and analyzed. The results revealed that all 11 samples were subtype B. There was no phylogenetic clustering or separation of the strains between IDU and FSW or between Tijuana and Ciudad Juarez nor was the Mexican strain phylogenetically distinct from other subtype B strains. Two of three drug naive FSWs had low-level HIV-1 resistance mutations. This community-based study demonstrated that HIV-positive IDUs and FSWs in Ciudad Juarez and Tijuana were predominantly infected with subtype B. Further prevalence studies on HIV-1 resistance mutations among FSWs in these border cities are warranted.

RESPONSE TO AMUNDSEN

Evidence of the effectiveness of AIDS prevention efforts has been constrained by the use of poor study designs, small sample sizes, short evaluation periods and a lack of control groups [1]. However, ‘These same flaws are common to a surprisingly high percentage of research in all areas of medicine, and are not necessarily more problematic in the AIDS area’[1]. These flaws are evident and have been acknowledged widely in the literature on the effectiveness of needle and syringe programmes (NSPs) [2,3]. In a recent editorial, Amundsen [4] relies on these limitations to question the status of NSPs as a ‘superior tool’ for HIV prevention and suggests that more emphasis be placed on testing and counselling to reduce risk behaviour in injecting drug users (IDUs). However, the evidence base for voluntary testing and counselling (VTC) is relatively weak compared to that supporting NSPs. VTC is most effective in reducing risk behaviours among serodiscordant heterosexual couples and those testing HIV positive [5]. While some studies show reductions in risk behaviour following a positive diagnosis [6], many indicate ongoing risk behaviour [7,8]. At best the effects of VTC are variable, with some [8–10], but not all [11], randomized controlled trials reporting a dose–response relationship, with greater reductions in risk associated with more intensive counselling. Evidence of beneficial effects in particular populations is especially weak [12], and many IDUs continue to engage in risk behaviours despite knowledge of their positive serostatus [13,14]. While some studies indicate that HIV-positive IDUs report less risk behaviour than those not tested or infected [15], a randomized trial [16] and a prospective study [17] found that VTC was not associated with a reduction in injection risk behaviour. To date, no trials have evaluated the impact of testing and counselling on HIV transmission, compared with no testing and counselling. However, prevention research is increasingly shifting its focus towards group and structural interventions that address the social and environmental contexts of risk [18] and the role of social networks and group dynamics [19]. The evidence to date suggests that VTC is clearly necessary, but not sufficient, in preventing the transmission of HIV and other blood-borne pathogens. As in other areas of medicine, evidence of the effectiveness of public health interventions is rarely clear-cut and policy makers have traditionally rejected putting all the eggs into a particular basket in favour of a range of interventions which, in turn, have different costs and varying levels of effectiveness. A recent study which examined the allocation of resources to NSP, methadone maintenance and condom distribution programmes targeting different population groups found that best allocations varied by epidemic scenario. In a setting characterized by 40% HIV seroprevalence among IDUs, allocating approximately 75% of the budget to NSP and 25% to a condom availability programme maximized the number of HIV infections averted. In a lower prevalence setting (5%), the best allocation expended almost all funds on methadone maintenance for HIV-positive IDUs [20]. NSPs are clearly a critical component of an effective harm reduction response. Unfortunately, questioning the efficacy of this vital public health tool on the basis of a lack of gold standard evidence may serve to undermine current attempts to scale up NSPs in settings where they are needed most.