People who inject drugs are at increased risk of HIV, tuberculosis (TB), and viral hepatitis B and C (HBV and HCV), in addition to overdose. Globally, around 11 million people inject drugs. Approximately 1 in 8 (or 1.4 million) of these people are living with HIV (UNODC World Drug Report, 2020), while 39.4% have viremic HCV infection (Grebely et al., Addiction, 2019).

Injecting drug use accounts for approximately 10% of new HIV infections globally (UNAIDS, 2020). And an estimated 23–39% of new HCV infections occur among people who inject drugs. Globally, 1 in 3 HCV deaths are attributable to injecting drug use. In some regions, such as Eastern Europe and Central Asia, prevalence rates for both HIV and HCV are particularly high. Furthermore, there are approximately 2.3 million HIV–HCV co-infections worldwide, of which more than half (1.3 million) occur in people who inject drugs (WHO, 2016).

WHO recommends a package of harm reduction interventions to reduce transmission of HIV, HCV and HBV, as well as deaths due to overdose, among people who inject drugs. These interventions also allow people who inject drugs to access the health-care system and engage with TB care and mental health services. Harm reduction – including needle/syringe programmes, opioid substitution therapy and community distribution of naloxone – is an evidence-based approach to HIV and HCV prevention, treatment and care for people who inject drugs. It is strongly supported by other United Nations agencies. Harm reduction interventions are essential to achieve the global targets for viral hepatitis elimination and control of HIV/AIDS epidemics.

However, criminalization of drug use and stigma and discrimination against people who inject drugs contribute to ongoing epidemics of HIV, viral hepatitis and TB. This is because people who inject drugs fail to access harm reduction and other health services. In many settings, harm reduction programmes are simply not available, or are extremely limited in accessibility and availability due to restrictive and ineffective policies and laws. Global coverage of harm reduction interventions is extremely low – less than 1% of people who inject drugs live in settings with sufficient, combined and high-coverage services.

A comprehensive package of services is recommended to address these infectious diseases in people who inject drugs.