Prevention in Focus

Spring 2011 

HIV prevention for people who inject drugs: Time for a global change

Carol Strike and Adrian Guta

The controversy over drug policies reached a new height last summer at the 2010 International AIDS Conference, held in Vienna, Austria. For decades, most countries have criminalized illicit drug use while many healthcare professionals, researchers and community members have advocated a harm reduction approach, one that minimizes the harmful consequences of illicit drug use. The AIDS 2010 Conference marked the launch of the Vienna Declaration, which calls for a full re-orientation of drug policies. The Vienna Declaration points to the failure of the international “War on Drugs” to achieve its stated objectives and calls for drug policies based on scientific evidence. So, what does the evidence tell us about the links between illicit drug use and the prevention of HIV? What does it tell us about the effectiveness of drug prohibition vs. harm reduction?


Coinciding with the release of the Vienna Declaration, The Lancet—one of the top scientific journals in the world—published an issue on “HIV in people who use drugs.” In a series of articles, scientists describe the extent of the global health problems associated with injection drug use and present the most recent evidence about effective interventions. We summarize some of the key issues addressed in these articles. When you get a chance, read the articles!

The backdrop

  • As of 2007, an estimated 15.9 million people around the world injected drugs and approximately 18% of injection drug users were infected with HIV.
  • In some parts of the world, such as Eastern Europe and Central Asia, 70% to 85% of injection drug users are HIV-positive.
  • Outside of sub-Saharan Africa, injection drug use accounts for approximately one in three new cases of HIV.1

Using a combination of strategies (including sterile needles or syringes, opioid substitution treatment and antiretroviral medications, among others) and treating illicit drug use as a public health issue rather than a criminal justice issue could significantly reduce the risks of HIV infection.

Comprehensive HIV prevention programs can reduce HIV transmission

Front-line workers know, and Louisa Degenhardt and her colleagues concur in one of the Lancet articles, that a combination of strategies is needed to effectively prevent HIV transmission among injection drug users and that those strategies need to reach as many people as possible.2 The long list of strategies include HIV testing and counselling, counselling to reduce the risk behaviours of individuals and couples, peers promoting changes in risk behaviours among their social networks, needle exchange programs, condom distribution, opioid substitution therapy, cognitive behavioural therapy, treatment of sexually transmitted infections (STIs) and antiretroviral treatment. Current evidence shows that each of these interventions reduces the number of injections, the riskiness of injection, sexual risk behaviours and/or the infectiousness of people living with HIV. Three of these interventions have proven to be especially beneficial—namely, opioid substitution treatment, needle and syringe programs and antiretroviral treatment (for HIV-positive people with CD4 counts lower than 350 cells).

Moreover, studies have shown that when a combination of these three interventions are provided to as many injection drug users as possible, HIV transmission may be reduced by more than 50%. For us to see this kind of impact, these programs must be readily available and accessible to as many drug users as possible.

Although providing drug users with opioid substitution treatment, clean needles and syringes, and antiretroviral treatment can cut HIV transmission in half, it is estimated that worldwide only 5% of drug injections involve a sterile needle or syringe; 8% of injection drug users have access to opioid substitution treatment; and 4% of HIV-positive injection drug users take antiretroviral medications.

Addressing risk environments important for HIV prevention

Most research on HIV and drug use focuses on the unsafe drug practices of individuals, such as sharing injecting equipment, which increase their risk of infection and early death. But people working on the front lines know that this captures only one side of a more complex story: HIV prevention among people who inject drugs is often influenced by social, political, economic and environmental factors that can influence a person’s ability to reduce their risk of HIV. Unfortunately, much of the research evidence we have about people who use drugs is framed in terms of the risk behaviours of individuals and does not take into account factors beyond a person’s control that may influence their ability to reduce their risk of HIV infection. (These include barriers such as lack of access to clean needles or syringes, condoms and antiretroviral medications; homelessness; incarceration; discrimination; unaffordable healthcare costs; lack of user-friendly health and social services; drug laws and policing practices that prevent drug users from accessing social services and healthcare; as well as other social and legal barriers.)

Recently, researchers have been trying to address this knowledge gap. The evidence we have suggests that reducing the social and environmental risk factors that impact people’s behaviours is key to preventing HIV. In a Lancet article entitled “HIV and risk environment for injecting drug users,” Steffanie Strathdee and her colleagues (2010) point to the need to look beyond the risk behaviours of individuals and examine the “risk environments” that help shape drug use practices, increase drug users’ vulnerability and produce harmful outcomes.11 They show how addressing “risk environments” could significantly alter the dynamics of HIV epidemics:

  • In Nairobi, Kenya, needle and syringe programs are illegal and opioid substitution therapy is a rarity. It is estimated that in Nairobi, between 2010 and 2015, 4000 new HIV infections will be caused by exposure to contaminated injection equipment. The social and political environment in the city and the rapid pace of its HIV epidemic are a challenge and implementing a single intervention is likely to fail. However, it is estimated that providing 80% of injectors with both opioid substitution treatment and needle and syringe programs could avert 26% of new HIV infections.
  • In Odessa, Ukraine, fear of police beatings for the possession and use of illicit drugs can lead to risky injection practices (for example, sharing syringes and the use of syringes pre-loaded with drugs). The elimination of police beatings could potentially reduce 2% to 9% of all new infections in Odessa.

Similar to the examples given by Strathdee et al in The Lancet, the experience of Vancouver’s safe injection site shows how addressing the “risk environment” of drug users in the city’s Downtown Eastside neighbourhood has altered the dynamics of its HIV epidemic. Insite—the first legal supervised injection site in North America—opened in 2003. Since that time, Insite has provided a clean, safe environment where users can inject their own drugs under the supervision of staff. Nurses and counsellors provide onsite access and referrals to drug treatment services and healthcare providers; as well as first aid and wound care. Insite has been the subject of much research and dozens of papers in peer-reviewed journals. The research has shown an array of benefits. These include a reduction in public injecting and needle/syringe sharing, increases in the use of treatment services and social programs, fewer injection-related infections and the saving of one life each year from overdose. At the same time, there has been no increase in crime. In 2008, a cost-effectiveness study estimated that over a 10-year period, 1191 cases of HIV infection and 54 cases of hepatitis C virus infection could be averted due to Insite.12,13,14,15,16,17,18,19,20,21,22,23,24,25

Use of the criminal justice system to solve drug problems can cause more problems

In most countries in the world (including Canada), the bulk of public resources dedicated to reducing illicit drug problems are used for enforcing punitive drug laws and incarceration. In one of the Lancet articles, Ralf Jürgens et al point out that there is no evidence that these measures have led to less drug use or diminished access to illicit drugs. Prohibiting drug use stigmatizes people who use drugs and can keep drug users away from HIV prevention services. The threat of being targeted by police can lead people to inject drugs more hurriedly, dispose of syringes in unsafe ways, and displace drug users away from health and social services.

In prison, many drug users continue to use drugs, where they are more likely to share injecting equipment. (A reported 56% to 90% of injection drug users worldwide have been incarcerated or spent time in detention centres.) In most countries, access to clean needles and syringes, opioid substitution, antiretroviral drugs and healthcare while incarcerated tend to be poor. Hence, there are reports of extensive HIV, hepatitis B and hepatitis C infection among injection drug users in prison.

By contrast, Argentina, Chile, Paraguay and Uruguay have decriminalized (abolished criminal penalties for) the possession of small amounts of drugs for personal use. And, in 2001, Portugal decriminalized the purchase and possession of all illicit drugs for personal use. Since Portugal changed its laws, there has been no increase in drug use, a dramatic decline in the number of new cases of HIV and drug overdoses, and modest declines in the numbers of new cases of hepatitis B and C. One of the concerns some have expressed about a harm reduction approach is the fear that such policies could lead to more widespread drug use. But, as Chris Beyrer et al highlight in the Lancet, the evidence suggests otherwise: Since Portugal shifted away from incarcerating drug users to emphasizing prevention and treatment, not only has there been no increase in drug use but the numbers of new HIV infections and overdoses have dropped.

Human rights—a foundation for HIV prevention

The harm reduction movement advocates drug policies that are based on scientifically sound evidence and respect for human rights. Ralf Jürgens et al (2010) remind us that many people around the world are not able to benefit from harm reduction initiatives and that human rights laws must apply to everyone, including people who use drugs.26 In the Lancet article “People who use drugs, HIV, and human rights,” the authors argue that “if the wider public health community is to apply human-rights-based approaches to HIV in people who use drugs, there has to be a greater understanding of rights violations.” They explain that widespread human rights abuses against people who inject drugs are core features of risk environments, act as barriers to testing, care, and prevention programs, and are social determinants of poor health.

The experiences of the drug users quoted in the article illustrate this point:

  • One injection drug user from the Ukraine explained: “Police are around this needle exchange point frequently. They have stopped me a few times. They look in my shopping bag… They ask me, ‘Where are you going? Why?’ They gave me warnings: ‘Don’t come around here. We don’t want to see you around here.’”
  • In an interview with Human Rights Watch, an injection drug user from Unnan, China said: “I’m afraid to take the first step and go to the [methadone] clinic because I don’t want to be put into detention. The police wait near the clinics.”
  • In another interview with Human Rights Watch, a drug user from Guangxi, China said: “Sometimes I’m afraid I might be sick with AIDS but I’d rather be sick and free than go to get tested, get arrested, and be sick in detox or re-education through labour.”
  • Similarly, a drug user in Thailand described how discrimination against drug users can prevent users from accessing treatment: “The doctor said if I use drugs, I can’t have ART.”

In short, human rights laws need to be in place and need to be respected for harm reduction programs to work. Finally, the authors of this article recommend that people who use drugs be more involved in developing and implementing drug policies, interventions, and related research and evaluation.

HIV prevention is achievable

The transmission of HIV and hepatitis C among people who inject drugs and to the larger community is highly preventable. We know how HIV is transmitted and we have a core set of interventions that have proven to be effective. However, in most countries, the threat and reality of criminal consequences prevents drug users from accessing these interventions.

Although many organizations and some municipalities in Canada have signed the Vienna Declaration, the federal government has refused to sign on, saying that the Vienna Declaration does not fit with the government’s drug policy.

In 2007, the Canadian government unveiled its National Anti-Drug Strategy. This strategy is based on three pillars: prevention (preventing drug use before it happens), treatment (treating drug users) and enforcement (tougher laws and the prosecution of drug producers and dealers). The Strategy has been criticized for the missing pillar: harm reduction. Harm reduction has proven to be a significant tool for reaching populations that use drugs, improving their health and stemming the spread of HIV, hepatitis C and other infectious diseases. Moreover, harm reduction programs build the trust necessary for users to engage in addiction treatment and recovery programs. Whereas Canada’s previous drug strategy included harm reduction policies and programs, the new Strategy’s missing pillar represents a shift in political ideology to a more conservative approach to many social issues, including drug use.

The Vienna Declaration urges governments and international bodies to replace drug prohibition laws with policies that reduce the harms of drugs and are based on scientifically proven approaches. Moving forward, we can change our policies, our research and our advocacy efforts to prevent HIV infections.


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About the author(s)

Carol Strike, PhD is an associate professor at the University of Toronto’s Dalla Lana School of Public Health, with 10 years of experience in harm reduction, addiction treatment and health services research.

Adrian Guta holds a Master of Social Work (specializing in diversity and social justice) and is currently undertaking doctoral studies at the Dalla Lana School of Public Health and the Joint Centre for Bioethics, at the University of Toronto. His dissertation research explores the Canadian HIV community-based research movement, with the aim of better understanding and supporting ethical decision-making in transgressive research practices. Mr. Guta has co-authored several articles on ethical issues in community-based research and emphasizes the importance of ethical and methodological reflexivity in his teaching. Mr. Guta is supported by an Ontario HIV Treatment Network student award.