The Centers for Disease Control and Prevention (CDC) cited a “disturbingly high” rise in the number of reported cases of hepatitis C virus (HCV) and blamed the trend on an increase in injection drug use.

“The shadow of the opioid crisis puts our nation’s progress at risk,” says Jonathan Mermin, MD, director of the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention. “Tackling hepatitis C requires diagnosing and curing people living with the virus and cutting off new infections at the source.”

Many people who became addicted to prescription painkillers transitioned to heroin or other cheaper injectable opioids. This prompted folks to share needles, which upped infection rates. “Effective treatment for hepatitis C has become even more relevant today in light of the recent surge in new cases due to rising opioid use,” writes Anna Suk-Fong Lok, MD, an assistant dean for clinical research at the University of Michigan Medical School, in an article published by the online journal The Conversation.

According to Lok, a preventive vaccine for hep C would be key in helping to eliminate this blood-borne illness.