The Maine Center for Disease Control and Prevention is reporting that new hepatitis B virus (HBV) cases across the state have more than doubled in recent years. Health authorities say an ongoing heroin crisis in the region is likely to blame, the Portland Press Herald reports.

Thus far this year, Maine’s CDC has reported 29 acute cases of hepatitis B in its state surveillance registry, more than twice as many as in 2014. The New England state also has a hepatitis B rate of 2.2 cases per 100,000 people, more than twice the national average.

State health authorities say sharing needles is a major risk factor for those recently diagnosed with HBV in the region. In fact, during its last update on hepatitis B, Maine reported that nearly 90 percent of those infected were injection drug users.

Maine also saw a major increase in new hepatitis C virus (HCV) cases between 2014 and 2015, but health officials say the spread of that viral liver disease seems to be slowing, with only 11 new HCV cases emerging in the state so far this year. Maine also experienced a record 272 drug overdose deaths in 2015, most of which were caused by heroin or prescription opioid use.

To help combat the addiction crisis, Maine health authorities say they will be accelerating public health education programs about hepatitis B and encouraging those at risk to be vaccinated against the virus. Currently, 13 locations across the state offer free HBV vaccinations. In addition, harm reduction advocates are now pushing Maine legislators to expand the state’s needle exchange programs with additional funding and more locations to help mitigate the spread of blood-borne illnesses.