Needle exchange programs, along with opiate replacements like methadone, can significantly reduce the risk of hepatitis C transmission through sharing injection drug use equipment, according to a study published in the journal Addiction and reported by Reuters.

There have been numerous studies demonstrating that needle exchange programs-community-based efforts that allow injection drug users to swap old hypodermic needles and other paraphernalia for clean works-and methadone programs curb users risk of contracting HIV, the virus that causes AIDS. Surprisingly, few studies have documented whether these programs also reduce the risk of transmitting hepatitis C virus (HCV).  In an effort to address this fundamental questions, researchers at the United Kingdom’s University of Bristol compiled results from six previous observational studies involving 919 injection drug users, 40 of whom contracted hepatitis C.

The researchers found that while seven percent of drug users who didn’t regularly use clean needles were infected with the hepatitis C virus, less than four percent of those who employed clean needles in all of their injections contracted hepatitis C.

Similarly, seven percent of those not on opioid replacement therapy contracted hepatitis C, as opposed to a mere three percent of those who received such treatment.

“The implication is that hepatitis C transmission can be reduced by opiate substitution therapy and needle and syringe programs, especially their combination,” said study co-author Matthew Hickman, BSc, MSc, PhD, Professor in Public Health and Epidemiology at the University of Bristol.