Three million HIV positive injecting drug users

New research suggests there could be three million injecting drug users (IDUs) worldwide who are HIV positive; and that the number of countries reporting injecting drug use has increased over the last decade.

The proportions of IDUs who are HIV positive is over 40% in nine countries with data. In an article published early online and in an upcoming edition of The Lancet, Dr Bradley Mathers, from the National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia, and colleagues from the 2007 Reference Group to the UN on HIV and Injecting Drug Use call for better data from around the world in view of the increasing importance of injecting drug use as a mode of HIV transmission in many regions.

This systematic review showed huge discrepancies worldwide. For example, in the UK, 0.39% of 15-64 year-olds are IDUs, of which 2.3% are thought to be HIV positive. In Spain, this proportion of IDUs is lower (0.31%), but the proportion of IDUs with HIV is many times higher (39.7%). Other examples of country figures, with proportion of 15-64 year old IDUs first and proportion of those who are HIV positive second are USA (0.96% / 15.6%), Australia (1.09% / 1.5%), Argentina (0.29%, 49.7%), China (0.25%, 12.3%), Ukraine (1.16%, 41.8%), Russia (1.78%, 37.2%), and Estonia (1.51%, 72.1%). In Europe, the highest proportions of IDUs among 15-64 year-olds were in Italy (0.83%) and Switzerland (0.65%); while the highest figures for proportions of IDUs that are HIV positive were Spain, mentioned above, and Portugal (15.6%). The authors estimate that there may be 15.9 million people worldwide who inject drugs.

The authors note a dearth of information from Africa, and express their concerns that in Africa a 'constellation of risk factors exists for the development of injecting drug use, as has occurred elsewhere'. For regions with data, the authors say: "Areas of particular concern are countries in southeast Asia, eastern Europe, and Latin America, where the prevalence of HIV infection among some subpopulations of people who inject drugs has been reported to be over 40%." A review in 1998 identified 129 countries with IDU, of which 103 reported HIV among IDUs. This latest research increases these numbers to 148 countries with IDU and 120 of those reporting HIV among IDUs. The authors say: "There is a pressing need to understand injecting drug use in all countries."

They conclude: "Injecting drug use occurs in most countries and HIV infection is prevalent among many populations of IDUs, representing a major challenge to global public health. People who inject drugs have the right to enjoy the highest standard of health attainable. There is a clear mandate to invest in HIV prevention activities such as needle and syringe programmes and opioid substitution treatments and to provide treatment and care for those living with HIV/AIDS. The magnitude of this risk has not been met with an equally concerted investment in research to accurately quantify the problem."

In an accompanying Comment, Dr Kamyar Arasteh and Dr Don C Des Jarlais, Beth Israel Medical Center, Baron Edmond de Rothschild Chemical Dependency Institute, New York, USA, discuss how various factors that could be contributing to increases in injecting drug use and conclude: "The one optimistic aspect of this rather gloomy situation is that, if HIV-prevention efforts are implemented on a large scale when prevalence is low in injecting drug users, it is possible to avert HIV epidemics in users. Thus it should be an imperative - for both resource-constrained countries and international donors - to implement large-scale evidence-based programmes for HIV-prevention whenever there is an indication of a developing injecting-drug-use problem."

Dr Bradley Mathers, National Drug and Alcohol Research Centre, University of New South Wales, Sydney T) +61 2 93850133 / +61 414411270