Ramping up programs for injection drug users is a key part in preventing transmission of hepatitis C.
A recent global review is the first of its kind to quantify the impact of needle syringe programs (NSPs) and opioid substitution treatment (OST) in reducing the risk of hepatitis C virus (HCV) infection.
Evidence shows providing injection drug users with sterile needles through NSPs or providing OST reduces injecting risk behavior and even HIV transmission; however, there has been little evidence of its impact on HCV transmission.
In a study published in Addiction, investigators sought to examine whether NSP and OST, solely or combined, effectively reduced the risk of HCV among injection drug users.
The scientists identified 28 research studies across Europe, Australia, North America, and China. They found the rate of new HCV infections per year was on average 19.0 for every 100 individuals.
Data from 11,070 injection drug users who were HCV-negative at baseline were combined in the analysis. Overall, 32% of subjects were female, 50% injected opioids, 51% injected daily, and 40% had been homeless.
The results of the study showed the use of OST reduced the risk of HCV infection by 50%, and was further reduced by 74% when combined with high coverage NSP. The authors noted that the evidence was both consistent and strong.
For the efficacy of NSP alone, the findings proved uncertain. In European studies, which tend to measure high coverage in terms of people who receive 100% sterile syringes per injection, the investigators found a more than 50% reduction.
In North America, coverage is often measured in terms of frequency of NSP attendance. Little effect was found, according to the study. Additionally, there were no randomized controlled trials (RCT) of OST or NSP on HCV.
“This is the first global systematic review of the quantitative studies on the effectiveness of OST and NSP on reducing hepatitis C,” said lead author Dr Lucy Platt. “Our findings provide strong evidence that OST especially in combination with high coverage of NSP can reduce HCV transmission. Up to half of people who inject drugs have hepatitis C: there is an urgent need to scale up these interventions to prevent on-going transmission, unnecessary deaths, and illness.”
More than 70 million individuals are living with HCV, and 3 to 4 million are newly infected each year.
“Globally, access to OST and NSP is poor and in some countries (such as Russian Federation) OST is unavailable,” said author Matthew Hickman. “Our evidence underpins European and global recommendations that OST and NSP should be expanded to prevent transmission of hepatitis C.
“Policies that make the cessation of injecting a requirement to qualify for OST and prevent the distribution of needles/syringe while using OST need to be removed to maximize reduction in HCV transmission. Scaling up OST and NSP is an essential part of comprehensive strategies to prevent HCV transmission and disease.”
Hickman added, “It is important also that the evidence base is strengthened. RCT are no longer ethical­­—–so better observational studies are needed with consistent measures of NSP and OST as part of the scaling up of these interventions or PWID.”