People who inject drugs (PWID) are one of the groups most affected by HIV and are 22 times more likely to have HIV than the general population. Injection drug use now accounts for an ever-growing proportion of people with HIV. On average 1 in 10 new HIV infections are caused by the sharing of needles. Moreover, it is estimated that 25% of new infections outside of sub-Saharan Africa are among PWID.

Globally, around 11 million people inject drugs, around 1 in 8 (or 1.4 million) have HIV, and about 39% have hepatitis C virus (HCV) infection. Three countries account for nearly half of all PWID globally–China, Russia, and the U.S.

Despite the increased risk of HIV for PWID, they are among those with the least access to HIV prevention, treatment, and healthcare. This is because drug use is often criminalized and stigmatized. In many settings, harm reduction programs are simply not available or are extremely limited due to restrictive and ineffective policies and laws.


PWID often share common factors, regardless of their background, that can make them vulnerable to HIV transmission. The following factors contribute to the global burden of HIV among PWID:

Sharing needles, syringes, and other injection equipment: PWID are at high risk for HIV if they use needles, syringes, or other drug injection equipment–such as cookers, cottons, or water–that someone with HIV has used. If equipment has been used by someone with HIV, infected blood left on or in the equipment can be injected into the next person who uses it.

Unfortunately, sterile equipment is not always readily available, especially in countries with no/low roll-out of syringe service programs (SSPs). A lack of awareness or education about safe injecting is another major reason for sharing needles and other equipment. This highlights the need for strengthened HIV prevention efforts for PWID, such as expanding coverage and support for comprehensive SSPs.

Criminalization and marginalization: Legislation that criminalizes possession and use of drugs for personal consumption leads to more risky forms of drug use. Along with other punitive policies and practices which discriminate against people with a history of drug use, criminalization reinforces the marginalization of PWID while also discouraging them from accessing harm reduction and other healthcare services. This hugely increases vulnerability to HIV infection and has a negative effect on HIV prevention and treatment outcomes.

Drug paraphernalia laws in some countries make it illegal to distribute or possess syringes for non-medical purposes. People can be arrested for carrying syringes which forces them to use shared ones instead. Despite overwhelming evidence that it has little or no impact on the number of people using drugs, the “war on drugs” approach continues to prevail in many countries. This discourages PWID from accessing targeted healthcare and harm reduction services and contributes to the spread of HIV.

Poverty: Poverty and drug use are linked in a complex and mutually reinforcing manner which contributes to the spread of HIV. Poverty may mean people must use cheaper ways of taking drugs such as sharing needles with others. Economic marginalization may lead to behavior associated with increased risk of HIV such as sex work.

Sex work: There is overlap between drug addiction and those involved in sex work. People who fall into both categories are particularly vulnerable to HIV. Sex work and drug use are illegal in most countries, so PWID who are sex workers are more vulnerable to frequent arrest, bribes, extortion, and physical and sexual abuse. In turn, this discourages many PWID who are sex workers from seeking harm reduction services or HIV prevention and treatment. Read more about HIV among sex workers.

Women who inject drugs: Women are more susceptible to HIV infection because of gender-based violence (GBV). Women may be pressured to share needles and engage in high-risk sexual activities. Women are also more likely to conceal their drug-taking behavior because of societal discrimination and the threat of losing custody of their children. This discourages them from accessing medical care and HIV services. Other studies have shown that women who inject drugs are more likely to experience sexual violence from police and law enforcement agencies. Read more about HIV among cisgender women and girls.

Incarceration: Estimates vary, but around 60-90% of PWID are incarcerated at some point in their life. The predominantly punitive global response to drug use also means that around 1 in 5 incarcerated people worldwide are being held on drug-related charges. In many countries, prisons remain environments with high levels of drug use and high prevalence of HIV. In this context, incarceration of PWID fuels HIV transmission, especially in overcrowded prisons where syringe sharing and unprotected sex is more common. There are significant gaps in prevention, treatment, and harm reduction services in many prisons around the world. Read more about HIV among people in jails and prisons.



Legalizing drug use, ensuring adequate harm reduction services, engaging PWID in the HIV response, and investing adequate funding in services for PWID are essential to addressing the HIV epidemic among PWID.

HIV counseling and testing

It is important for PWID to get tested for HIV regularly and to know their status. Knowing one’s status helps determine the best prevention or treatment options. The World Health Organization (WHO) recommends at least annual HIV testing for PWID. Find an HIV testing site near you.

Pre-exposure prophylaxis (PrEP)

PrEP is the daily use of antiretroviral drugs (ARVs) to prevent HIV infection. In 2015, the WHO recommended the use of PrEP for PWID.

It is important that other forms of combination prevention are offered alongside PrEP, such as SSPs and opioid replacement therapy (ORT), as these are the most effective ways of preventing HIV infection from injecting drugs.

Harm reduction programs

Harm reduction programs include SSPs and ORT. These are effective in preventing HIV because they provide clean needles and other injection equipment to PWID and offer substitution medicines such as methadone as an alternative to injecting drugs. Despite their resounding success in various settings worldwide, of the 140 countries that reported data on PWID to UNAIDS in 2018, only 86 have SSPs and 44 have ORT available. These programs need to be scaled up everywhere in order to have a preventative effect for PWID and the wider population.

Law enforcement practices, human rights, and legal education

The criminalization of drug use and possession can hinder attempts to engage PWID with available HIV services. Decriminalization would be a more effective approach because PWID would not be forced underground to conceal their habit and escape arrest, but rather be free to engage in the HIV response and be active in protecting their own health.

PWID-led, community-based services that address legal and social barriers can have a real and lasting impact on the lives of PWID, including reducing their vulnerability to HIV.

Addressing stigma and discrimination

Although substance use disorder is a health issue that requires treatment, it is often viewed as a criminal activity. Stigma and mistrust of the healthcare system may prevent PWID from seeking HIV testing, care, and treatment. PWID face serious discrimination from a multitude of sectors of society, including a lack of inclusion in medical trials. Including PWID in research is important in the global HIV response. Much of society is indifferent to the rights of PWID; they must be shown the same human rights as others.


Access to antiretroviral therapy (ART) among PWID is plagued by controversy and stigma in many parts of the world, despite the fact that people who are virally suppressed on treatment are much less likely to transmit HIV to others. In many countries, however, PWID with HIV are less likely to access ART than the general population.

Many governments have policies that require absolute abstinence from illegal drug use before ART is provided. This deters PWID from seeking ART if they are forced to abstain from their drug addiction. Supporting PWID to adhere to their treatment (taking ARVs at the same time every day at least 95% of the time) is an essential part of ensuring treatment is successful.

In the U.S., assigned male at birth PWID have lower viral suppression rates, assigned female at birth PWID have about the same viral suppression rates, and assigned male at birth gay and bisexual PWID have higher viral suppression rates compared to all people with HIV.

Received some care Retained in care Achieved viral suppression
Assigned male at birth PWID with HIV 60% 47% 50%
Assigned female at birth PWID with HIV 69% 54% 57%
Assigned male at birth gay and bisexual PWID with HIV 73% 57% 60%
All people with HIV 65% 50% 56%


Taking HIV medicine every day can make the viral load undetectable. People who get and keep an undetectable viral load (or remain virally suppressed) can stay healthy for many years and have effectively no risk of transmitting HIV to their sex partners.

WHO has produced comprehensive guidance on HIV services for PWID and recommends that adherence can be increased significantly by addressing HIV stigma and discrimination.


People who inject drugs (PWID) are one of the groups most affected by HIV and are 22 times more likely to have HIV than the general population. A combination of accessible HIV prevention approaches are needed to reduce HIV transmission among PWID. Better monitoring of this key affected population would also help inform effective HIV prevention responses.

Harm reduction measures, including syringe service programs and opioid replacement therapy, should be implemented more widely and scaled up where they do exist.

Stigma and discrimination against PWID needs to be tackled so they can access treatment freely without fear and reduce the risk of being exposed to HIV. This would also lessen the chance of HIV transmission to other population groups through sex work and unprotected sex in general.

The “war on drugs” and criminalization of PWID is pushing them away from services that could improve their health. Countries need to reconsider punitive laws and measures, such as incarceration and drug registers, that are very prominent barriers to addressing HIV among PWID.


CDC: HIV and People Who Inject Drugs

Avert: People Who Inject Drugs, HIV And AIDS

WHO: People who inject drugs

Reviewed May 2021

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