Australia's free and legal syringe exchange programs have led to an extremely low incidence of new HIV infections among injection drug users (IDUs), aidsmap reports. Publishing their findings in the journal AIDS, researchers conducted a retrospective study in which they examined the incidence of infection among IDUs who participated in the Australian Needle Syringe Program Survey and underwent multiple HIV tests between 1995 and 2012.

The investigators included in their analysis IDUs who were HIV negative at the baseline and who had at least two HIV tests that were separated by a minimum of a year during the period of the study. After combing 34,000 records, the researchers drew a cohort of 3,490 people who between them accounted for 8,763 records. The median time between HIV tests was two years.

During the study, 17 out of this group tested positive for HIV, resulting in an incidence rate of 0.11 per person-years. Twelve of those seroconversions, or 71 percent, were among gay men, indicating an increased likelihood of that sex was the source of their transmissions. There were no other characteristics associated with acquiring the virus.

To read the aidsmap story, click here.

To read the study abstract, click here.