Risk for Hepatitis C Virus High Among PWID and Share Needles

People who inject drugs (PWID) and participate in receptive needle sharing (RNS) are vulnerable to higher infectivity rates for hepatitis C virus infection, according to a paper published in Open Forum Infectious Diseases.

Investigators from University of New Mexico Health Sciences Center recruited 344 young PWID volunteers who participate in RNS in order to estimate per-event hepatitis C virus infectivity in this population. Injection drug use is the most common route of hepatitis C virus infection, the study authors added. Rates have been increasing, especially among young PWID, and RNS is associated with almost a 2-fold higher relative hazard of incident hepatitis C virus.

The participants, who were negative for hepatitis C virus at baseline, underwent at least 2 follow-up visits throughout the study period, which lasted from 2003-14. The investigators included the first hepatitis C negative through the first hepatitis C positive visit in their analysis. They also used RNA tests to determine infection status.

About 3 in 5 of the patients were male and the median age at first injection was 18 years. The participants reported injecting mostly heroin (71%). In the previous 3 months, about a third of the participants reported using borrowed needles from another, and a third also reported engaging in receptive ancillary equipment (such as cookers or cottons) sharing, the study authors learned. Among those, were 35 participants who became hepatitis C positive without reporting any needle or RNS exposures.

There were 118 participants with incident hepatitis C, including primary infection (101) and reinfections (17) over the obstruction period, the study authors said. Additionally, 10% of those with primary infection cleared their infection at some point during the observation period.

There were 440 study participants who did not meet the criteria and were therefore excluded due to not having the appropriate follow-up data. However, the study authors said these participants were also more likely to be male, report younger age at first injection, fewer days injecting meth/amphetamine in the past month, and a higher proportion reported injecting heroin and speedballs in the previous 3 months. More of these participants reported engaging in RNS and receptive ancillary equipment sharing in the last 3 months. There were no differences between the groups in terms of race, receptive backloading, age at enrollment, education, number of injection days in the past month, injections per day in the past month, or number of times in the last month engaged in RNS with the 3 people with whom they injected most frequently.

“It is well accepted that hepatitis C prevention should include strategies to reduce the number and frequency of high-risk exposures to hepatitis C through RNS, and that widespread availability of unused injecting paraphernalia via syringe service programs can reduce hepatitis C incidence,” the study authors concluded. “Treatment for opioid dependence can reduce incidence through reductions in injection frequency… These estimates should help to inform policies to increase availability of clean and sterile injecting equipment to reduce RNS and hepatitis C infection rates.”