The threat of an impending HIV epidemic in many countries now facing the contributing injection drug use epidemic is clear. The need to implement effective and cost-effective programs is also clear. The challenges for policymakers are to, informed by evidence, choose options for action, and tailor these interventions to a country’s unique economic, political, cultural, legal, and public health context.
Chapters 2 and 3 presented evidence on the effectiveness of HIV prevention interventions for injecting drug users, to inform such policymaking. This chapter summarizes the Committee’s findings regarding the effectiveness of those interventions, knowledge gaps, and future research needs. The chapter also presents considerations for policymakers in high-risk countries in shaping their HIV prevention programs for IDUs. Based on these considerations, the Committee offers recommendations for countries implementing such programs.
SUMMARY OF THE EVIDENCE
Eastern Europe, the Commonwealth of Independent States, and significant parts of Asia are experiencing explosive growth in new HIV infections, driven largely by injecting drug use (UNAIDS, 2006). While the primary route of transmission in most of these areas is sharing of contaminated injecting equipment, sexual and perinatal transmission among IDUs and their partners also plays an important and growing role. In many highly affected countries, rapid growth in the number of IDUs infected with HIV
has already created a public health crisis. Countries where the level of HIV infection is still relatively low have the chance—if they act now—to slow the spread of HIV.
A variety of HIV prevention programs targeting IDUs have been shown to be effective in reducing HIV-related risks.1 For injecting opioid users seeking treatment, opioid agonist maintenance treatment is the only consistently effective treatment for opioid dependence. Studies show that methadone and buprenorphine reduce illicit opioid use, injection-related HIV risk behavior, and risk of HIV seroconversion among people with opioid dependence. Opioid antagonist medication is another pharmacological treatment option for opioid-dependent individuals who will not accept or cannot gain access to opioid agonist maintenance therapy. Despite strong pharmacological evidence and theoretical potential for naltrexone, evidence regarding its efficacy in controlled clinical trials is inconclusive. Naltrexone is likely to be most successful for patients whose adherence to medication and retention in treatment can be closely monitored and facilitated. Psychosocial interventions alone have not been shown to be consistently effective in treating opioid dependence.
For injecting non-opioid users seeking treatment, no pharmacotherapies have been found to be consistently efficacious in treating stimulant dependence. Contingency management, a behavioral intervention, is an efficacious treatment for stimulant dependence, but additional research is needed on the feasibility of its application outside of research settings. There is modest evidence of efficacy of several other behavioral or psychotherapeutic approaches in addressing stimulant abuse, including individual drug counseling and intensive group drug counseling, cognitive behavioral therapy, and community reinforcement combined with contingency management. While there is weak evidence regarding the effectiveness of therapeutic communities, drug anonymous groups, and abstinence-based outpatient treatments, these are important treatment options for opioid-dependent individuals who will not accept or cannot gain access to opioid agonist maintenance treatment, or for individuals dependent on other classes of drugs. Those seeking effective interventions for non-opioid users should consider these behavioral or psychosocial interventions, but funders and policymakers are urged to collect rigorous evaluation data if they are selected.
For injecting drug users who cannot gain access to treatment or are not ready to consider it, multi-component HIV prevention programs that include sterile needle and syringe access reduce drug-related HIV risk behav-
ior, including self-reported sharing of needles and syringes, unsafe injecting and disposal practices, and frequency of injection. Sterile needle and syringe access may include needle and syringe exchange (NSE) or the legal, accessible, and economical sale of needles and syringes through pharmacies, voucher schemes, and physician prescription programs. Other components of multi-component HIV prevention programs may include outreach, education in risk reduction, HIV voluntary counseling and testing, condom distribution, distribution of bleach and education on needle disinfection, and referrals to substance abuse treatment and other health and social services. If sterile needle and syringe access is not available, IDUs can prevent HIV transmission if they properly use bleach to disinfect injecting equipment. Finally, outreach and education reduces self-reported drug-related risk behavior, and is an important and effective strategy for encouraging behavioral change, providing education on preventing HIV transmission, and referring IDUs to other health and social services.
Yet knowledge gaps remain regarding the effectiveness of some HIV prevention programs among IDUs. More research is needed to identify the additional benefits and cost-effectiveness of adding psychosocial interventions to opioid agonist maintenance treatment for opioid-dependent people in high-risk countries, and to determine the relative effectiveness of those interventions in particular cultural contexts and patient subgroups. Research is also needed on the relative effectiveness of various psychosocial interventions in treating opioid dependence in situations where opioid agonist maintenance therapy is not available or accessible. Finally, research is needed on the effectiveness of naltrexone for different patient populations and in different settings.
For non-opioid dependence, research is needed regarding effective pharmacotherapies for stimulant abuse, particularly amphetamine-type stimulants, which have emerged as a major problem in many parts of the world. In addition, there is a need to develop cost-effective and feasible alternatives to voucher-based contingency management approaches for treating stimulant dependence.
Related to sterile needle and syringe access, several areas deserve future research. For example, information on unintended consequences from needle and syringe exchange—such as the possibility of recruitment of new drug users and expansion of drug networks—is scarce. Although the few studies that have examined unintended consequences have not found them, future evaluations should look specifically for unintended outcomes, and—if found—develop strategies for addressing them.
In addition, while laboratory studies have shown that undiluted bleach is an effective disinfection agent, field studies show that, in practice, drug users do not correctly follow disinfection procedures, and that they fail to effectively disinfect syringes. More research is therefore needed on alterna-
tive bleach disinfection techniques that are both simple and acceptable, and on the best methods to educate IDUs on those techniques. The Committee is also aware that in some countries, bleach is not available or acceptable for use. While alternative disinfectants (such as water, alcohol, hydrogen peroxide, and detergent) have been examined in laboratory settings, the Committee did not identify any studies of the effectiveness of those options in field settings, and calls for more research in this area.
Furthermore, in light of persistently high incidence of hepatitis C virus (HCV) among needle and syringe exchange participants, more research is also needed on the impact of NSE and related prevention services on the incidence of HCV among IDUs. And while multi-component prevention programs that include needle and syringe exchange have been shown to reduce drug-related HIV risks, questions remain about the specific contribution of individual elements to reductions in risk behavior and HIV incidence. Elements of these multi-component prevention programs can be resource intensive. Further research is needed to identify the most effective and cost-effective combination of programs that are feasible to implement in high-risk countries.
As noted, we would not expect interventions that target drug-related risk behavior—such as sterile needle and syringe access and pharmacotherapy for opioid addiction—to decrease sex-related HIV risk behavior, unless they are combined with additional risk reduction efforts targeting sexual behavior. Because of the strong correlation between drug use and high-risk sexual behavior, prevention programs and evaluations should devote more attention to reducing sexual risk behavior. More research is needed to identify the most effective sexual risk reduction strategies for IDUs, and on how to successfully integrate these strategies into existing programs, such as drug dependence treatment, multi-component programs that include sterile needle and syringe access, and outreach and education.
While such knowledge gaps require further research, they should not deter developing and transitional countries from implementing HIV prevention programs, particularly those with strong evidence of effectiveness. Failing to act will lead to further spread of HIV—not only among IDUs but also in the general population through sexual and perinatal transmission.
CONSIDERATIONS FOR POLICYMAKERS
The design of approaches to control HIV epidemics among injecting drug users depends on many factors. Scientific evidence should provide the foundation for the policymaking process. However, each country and community will also consider its own economic, cultural, legal, religious, and ethical climate. The choice of programmatic strategy must factor in the local context, and local programs must be tailored to fit that context.
Economics in resource-constrained countries is a key contextual factor that can influence the choice of programs and the strategy and pace with which they are implemented. The state of the medical and public health infrastructure may also impose practical constraints on the ability to implement programs in the short-term. Policymakers must also consider the balance between criminal justice and disease prevention. The nature, extent, strengths, and infrastructure of any broader population-based efforts to intervene in drug use and HIV epidemics in general can form the basis for efforts focusing specifically on preventing HIV among IDUs. Rather than offering a formulaic approach to step-by-step implementation, the Committee provides considerations for program building and decisionmaking based on national context. Whatever criteria policymakers use to decide which programs to implement and how, they must make provisions to learn from incremental implementation—especially to address the information gaps identified in this report.
Many high-risk countries face severe resource constraints. In these circumstances, HIV prevention programs for IDUs will run up against competing demands from other compelling interventions, both within the health sector and outside it. External donor funds can help ameliorate these constraints, but such resources may not be sufficient for large-scale program implementation.
Under such circumstances, financial decisionmakers may need to understand the economic advantages of pursuing HIV interventions among IDUs. Cost-effectiveness analyses (CEA) and cost-benefit analyses are standard methods used by economists to assess the potential gains from specific health and other interventions. CEA assesses the cost of achieving a one-unit gain of some outcome, such as an HIV case prevented or a death averted. Because the outcome measure is usually an indicator of health, this method is probably most useful for comparing health interventions, and therefore in allocating budgets of the Ministry of Health or donor funds allocated to health. Cost-benefit analysis is better equipped to make comparisons across various sectors, as outcomes are also evaluated in terms of money.
The bulk of existing research on the cost-effectiveness of HIV prevention programs for IDUs comes primarily from the United States and other relatively resource-rich countries. Models and empirical data from these countries indicate that methadone maintenance treatment is associated with reductions in expenditures for injection-related events such as comorbidity, crime, and transmission of HIV infection to others (Gerstein et al., 1997; Pollack and Heimer, 2004). Available literature suggests that methadone
maintenance treatment (MMT) yields monetary benefits that are several times the costs of the intervention, particularly if accompanied by incentives for drug users (Gerstein et al., 1994; Doran et al., 2003; Hartz et al., 1999). Another study—an analysis based on a randomized controlled trial—suggests that buprenorphine and methadone are equally cost-effective in the treatment of opioid dependence (Doran et al., 2003). Some mathematical models also suggest that programs that include needle and syringe exchange are cost-effective in controlling HIV transmission (Laufer, 2001; Cabases and Sanchez, 2003).
While evidence shows that both NSE and MMT are quite cost-effective in resource-rich countries, these studies are not themselves strong evidence for cost-effectiveness in high-risk countries, which are often resource-constrained. Simulation models can provide a useful platform for examining potential cost-effectiveness in populations with characteristics different from those on which existing studies are based. Thus, while developing countries can anticipate overall savings from combating HIV among IDUs, both program costs and the magnitude of the savings will vary by country, establishing the question of cost-effectiveness as an important research topic.
Cost-effectiveness can also guide implementation for countries that cannot afford a comprehensive and generally available approach—or do not have enough trained workers to implement it. These countries may find that a less efficacious yet more cost-effective program works best. For example, although research suggests that agonist maintenance therapy can be more effective if provided with psychosocial services, some countries may not be able to afford to offer counseling with such therapy, or may not have enough trained counselors. Those countries may decide initially to make agonist treatment alone widely available, to maximize the overall benefit. Other countries may choose to place initial emphasis on training medical personnel. Rigorous approaches to documenting the cost-effectiveness of different approaches, with attention to unique settings—such as the impact of large-scale programs with limited services versus smaller, more comprehensive programs, or compared with training for health counselors—are critical.
As discussed in Chapter 1, for effective HIV prevention efforts to exert a public health impact, they must be scaled up to provide adequate coverage of the target populations. Scaling up prevention programs, particularly opioid agonist maintenance treatment, imposes certain infrastructure requirements. These include the availability of a sufficient pool of trained treatment providers, pharmacists, outreach workers, drug and alcohol counselors, infectious disease specialists, and other professionals to carry out the
chosen programs, as well as the physical infrastructure, commodities, and funding to enable them to do so. In some places, broad scale-up of interventions will require a parallel scale-up of training and accreditation programs for health care workers. Similarly, for pharmacotherapy programs for opioid dependence, clinical guidelines (regarding patient eligibility criteria, dosage levels, and contraindications with other drugs, for example) may need to be adopted or enhanced. Information systems may also be needed to track and ensure consistent supply of commodities such as medications and needles (WHO et al., 2004; IOM, 2005).
Some high-risk countries may have limited public health, drug treatment, and overall medical infrastructure and operating capacity. These countries will have to make pragmatic decisions regarding which approaches they can pursue. Some scientifically sound and ethically acceptable approaches may not be immediately feasible in particular locations because facilities, supplies, or human capacity are inadequate. Programs with strong evidence of effectiveness may be less effective when scaled up if enough human and technical capacity is not available. Some communities may therefore have to choose between covering relatively few people with programs likely to have beneficial effects, and reaching a large number of those in need with potentially less effective programs.
The recent scale-up of antiretroviral treatment of HIV/AIDS in developing countries has highlighted some of the infrastructural challenges that may occur when expanding HIV prevention programs for IDUs (IOM, 2005). Trained physicians can provide only a small fraction of the care for HIV/AIDS, and this shortage of human resources will only worsen in many countries over the short term (IOM, 2005). Both HIV care and the care of IDUs will require a steady influx of trained professionals.
As with the scale-up of antiretroviral treatment, injecting drug users in need of care may live in densely populated urban settings, or in more disbursed rural communities with less access to services. Some policymakers consider geographic disparity in access to care unacceptable, and have quickly established widely dispersed programs (IOM, 2005). This strategy, of course, creates its own challenges, in that broadly distributed but ineffectively implemented programs may reduce the overall public health impact.
Some needs for managing HIV prevention and care in high-prevalence countries and for addressing the health needs of injecting drug users are so intertwined that close integration of programs may be advantageous by allowing the efficient sharing of physical facilities, supply chains, administrative systems, treatment providers, counselors, and other types of personnel. Efforts to combat HIV and tuberculosis have driven the development of innovative programs for ensuring that patients receive their daily dose of medication. Research also shows that providing directly administered antiretroviral therapy (DAART) at methadone clinics or as part of a com-
munity-based delivery program can lead to substantial clinical benefits for IDUs (Lucas et al., 2006). Community-based partners that support directly observed antiretroviral therapy have improved compliance in some places (Farmer et al., 2001). The global response to HIV/AIDS is also showing that reliable systems for ensuring an unbroken supply line for antiretroviral drugs are critical. The care of injecting drug users in hard-to-reach areas may benefit from some of the systems for providing outreach and acquiring and transporting commodities created for the global scale-up of HIV/AIDS.
Public perception also helps shape the choice of strategies to prevent HIV transmission and reduce illicit drug use. Some view public health interventions that provide access to sterile injecting equipment or opioid agonist treatment negatively because these interventions aim to reduce the harms related to drug use rather than prevent drug use itself (NRC and IOM, 1995; Gostin, 1991). These groups may see such harm reduction efforts as condoning rather than condemning illegal drug use. Local communities may also object to programs that include needle and syringe exchange and opioid agonist maintenance treatment because they fear that these programs will attract drug users who may commit crimes and discard needles and other drug paraphernalia in their neighborhoods (NRC and IOM, 1995). Public attitudes have affected the number and location of clinics providing opioid agonist treatment, as efforts to open such clinics sometimes elicit intense local opposition (IOM, 1995).
Stigma and discrimination can also affect whether drug users seek HIV prevention services. Public attitudes toward drug dependence are overwhelmingly negative (NRC and IOM, 1995). Medical professionals sometimes share these attitudes, and may be antagonistic to treatment. These attitudes of health care professionals can discourage IDUs from seeking treatment (Ritson, 1999), as can negative attitudes of pharmacists toward IDUs seeking to purchase clean injecting equipment (Taussig et al., 2002). Furthermore, drug treatment professionals are often divided about providing opioid agonist maintenance treatment, with some viewing it as conflicting with abstinence-based treatment (IOM, 1995).
Some national policies reflect these concerns (see the case studies in Appendix C) (NRC and IOM, 1995; Burris et al., 2003). For example, in Russia, methadone and other opioid agonist treatment programs are illegal because of the widespread view that these programs condone addiction (Personal communication, V.N. Krasnov, Russian Society of Psychiatrists, June 16, 2006). The U.S. Congress, reflecting similar concerns, banned federal funding for needle and syringe programs in 1988—and this ban remains in effect. Nonetheless, some U.S. cities allow NSE under exceptions
for public health emergencies and through other legal actions, but these programs are often funded by private donors and nongovernmental organizations, and less often by states (Burris et al., 2003).
Gostin (1991) illustrates the inherent tension—in this case in the United States but which may also occur in other countries—surrounding certain interventions: “Needle exchange programs cannot proceed without the co-operation of the very groups that traditionally oppose them-law enforcers and community leaders. The conflict between public health and criminal justice is illustrated by the dilemmas inherent in needle exchange: public health officials in some of the highest seroprevalence cities cannot establish exchange programs without first obtaining authorization from the state under needle prescription laws; the police must agree not to arrest, and the district attorney not to prosecute, people using drug paraphernalia distributed under the public health program; and community leaders must agree to the location of needle distribution centers which, if they are to be effective, need to be situated in poor urban areas.” (p. 297)
Several studies suggest that the involvement and education of key stakeholders, such as community members, government agencies, nongovernmental groups, public health officials, and law enforcement are critical to the success of HIV prevention programs for IDUs. For example, a study of needle and syringe exchange in Northern Thailand found that the success of the program depended on cooperation of key parties in the community (Gray, 1995, 1998). This study recommended that mechanisms to ensure cooperation, education and training, and evaluation coincide with the introduction of needle-exchange programs (Gray, 1995). Similarly, before launching a pilot needle and syringe exchange in Vietnam, staff members conducted workshops to help build community awareness and acceptance of the program (Quan et al., 1998). Such communication often reveals that disagreements over priorities and strategies often stem from a lack of information on the focus, methods, and evidence base of the competing factions.
The Committee recommends that public health and criminal justice officials, key community leaders (religious, educational), and community members work together at international, national, regional, and local levels to develop interventions that balance their respective missions in fighting both HIV/AIDS and drug epidemics.
Sustainability and Evaluation
Concerted national efforts to limit the transmission of HIV among IDUs must begin now. Nations must approach these efforts with both immediacy, to break the cycle of HIV transmission, but also with a longer-term view, to sustain progress.
Although reviewing the evidence on primary programs for preventing
drug use was beyond the scope of its charge, the Committee believes that programs to prevent the initiation of injecting drug use—and drug use in general—can and should be part of a comprehensive, sustained approach to preventing HIV transmission among IDUs. Broader population-based efforts at HIV awareness and prevention can provide a foundation for sustaining such efforts for IDUs.
Similarly, investments in the infrastructure to deliver clinical and supportive services to the general population will be needed and will have benefits beyond the IDU population. Maintaining infrastructure and sustaining funding is central to ensuring continuous services. Programs that do not have sustainable funding are at risk of interruption. Service interruptions could have serious implications for individuals receiving medication for opioid dependence and other IDUs receiving treatment or preventive services.
As part of a sustained effort, the Committee repeats its recommendation that such approaches be monitored and evaluated, and modified based on such evaluations. Scale-up of prevention efforts should include staggered program designs or other approaches that permit the evaluation of effectiveness, alongside more rigorous efforts to experiment with different implementation choices to see which ones work best.
In making decisions regarding implementation, policymakers and other stakeholders should consider several recommendations:
Recommendation 4-1: Because a variety of interventions have been shown to be effective, high-risk countries should act now to prevent the growing problem of HIV among IDUs, their partners, and children.
Recommendation 4-2: To increase their acceptability and likelihood of success, HIV prevention interventions for IDUs should be:
Tailored to local circumstances and implemented in a culturally appropriate manner;
Coupled with cost-effectiveness evaluations to improve resource-allocation decisions;
Scaled-up to provide adequate coverage of the interventions to the target populations in order for programs to have a public health impact;
Integrated with strategies to combat stigma and discrimination among drug users and HIV-infected people;
Coordinated among national, regional, and local public health, criminal justice, and community leaders to develop a framework for interventions that balance their respective missions;
Complementary to broader interventions in drug use and HIV, including primary prevention;
Built upon plans for fiscal and infrastructure sustainability;
Coupled with monitoring and evaluation.
Nations where the HIV pandemic is newly emerging can and should take effective action now to stem the tide of this tragic and preventable illness. In countries where injecting drug use is the primary source of HIV infection, national programs must address the challenges of both drug use and HIV. The Committee has reviewed the evidence regarding interventions for injecting drug use and HIV among IDUs, and hopes it has provided policymakers a knowledge base regarding what works. The Committee recognizes though that each country will pursue a different combination of interventions, reflecting its economic circumstances and legal, ethical, and cultural traditions. However, these policy decisions should not be based on erroneous understanding if scientific truth is available. The Committee believes that the evidence-based conclusions and recommendations in this report can provide an important foundation for governments and communities engaging in economic, legal, and ethical debates about these issues.
Evidence on effective interventions provides a solid basis for action now. The experiences of other nations with extensive HIV epidemics underscore the urgent need for an immediate response. As policy unfolds into programmatic action, nations should also evaluate their implementation, to inform the next generation of responses to drug dependence and HIV.
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