quality and those of lesser quality, and then to weigh the credibility of the findings according to their completeness and soundness. Using this approach, the panel based its conclusions on the pattern of evidence provided by a set of high-quality studies, rather than relying on the preponderance of evidence across less scientifically sound studies.
On the basis of its review of the scientific evidence, the panel concludes:
Needle exchange programs increase the availability of sterile injection equipment. For the participants in a needle exchange program, the fraction of needles in circulation that are contaminated is lowered by this increased availability. This amounts to a reduction in an important risk factor for HIV transmission.
The lower the fraction of needles in circulation that are contaminated, the lower the risk of new HIV infections.
The act of giving a needle to an injection drug user has a powerful symbolism that has sparked fears about the potential negative effects of needle exchange programs. However:
There is no credible evidence to date that drug use is increased among participants as a result of programs that provide legal access to sterile equipment.
The available scientific literature provides evidence based on self-reports that needle exchange programs do not increase the frequency of injection among program participants and do not increase the number of new initiates to injection drug use.
The available scientific literature provides evidence that needle exchange programs have public support, depending on locality, and that public support tends to increase over time.
Needle exchange programs should be regarded as an effective component of a comprehensive strategy to prevent infectious disease.
Although HIV has been shown to be susceptible to inactivation by bleach under idealized conditions in the laboratory, epidemiologic studies have not demonstrated a significant protective effect against HIV infection for injection drug users who report consistent use of bleach to decontaminate