After prison, people who inject drugs (PWID) have a substantially increased risk of contracting HIV and hepatitis C virus (HCV), according to a new study published in the Lancet. The study found that recent incarceration was associated with an 81 percent increase in HIV risk and a 62 percent increase in the risk for HCV, aidsmap reports.

For the study, researchers identified 41 studies (21 of which were unpublished) addressing this question between 2000 and 2017. Study locations monitored injection drug users in Australia, Canada, the Czech Republic, France, Greece, India, Ireland, Mexico, Spain, Thailand, the U.K. and the United States. Recent incarceration was defined as release from jail within the past three, six, or 12 months or since last follow-up.

In addition, researchers found that the effect of recent or past incarceration on HIV risk did not differ by geographical region or country income level. The effect of incarceration on HIV risk was found to be much higher among younger participants compared with older ones.

For HCV, location and income level also did not have a significant impact on risk post-incarceration. However, the effect was greater in countries with higher rates of incarceration.

Study authors say their findings have important policy implications, especially since it’s estimated that up to 58 percent of people who inject drugs will experience incarceration. In addition to pushing for the decriminalization of illicit drug use, the report states that new interventions are needed in prison systems in order to minimize HIV and HCV risk, including better linkage to care for people recently released from prison and easier access to syringe exchanges and opioid substitution services, for example.

“Our findings are consistent with studies that find that incarceration is associated with relapse to injecting drug use and that recently incarcerated PWID exhibit increased injecting risk behavior and reduced access to harm reduction interventions compared with PWID who do not report recent incarceration.”

To learn more about the study, click here.