Fentanyl, a powerful synthetic opioid up to 50 times more powerful than heroin, is now the No. 1 cause of overdose deaths in Virginia, according to the state’s latest estimate on its ongoing opioid crisis. Virginia health officials also report that needle sharing and hepatitis C virus (HCV) rates are on the rise, raising the risk for injection drug users, Richmond.com reports.

Law enforcement officials in Virginia say fentanyl is increasingly being laced with heroin and that many of those who overdose do not know what they’re injecting until it’s too late. The powerful drug contributed to 618 of the state’s total 1,133 opioid-related deaths last year, outranking both heroin and prescription painkillers in its deadly potential.

Because it can be developed in a lab, fentanyl is cheaper and more efficient to produce than heroin. Originally manufactured as a pharmaceutical painkiller, it is now being produced illegally in the United States with precursor chemicals shipped in from China through either Mexico or the Southwest United States.

In conjunction with the opioid epidemic, state health officials say they have noticed a major increase in the number of new hepatitis C cases in Virginia over recent years owing to injection drug users sharing needles. In 2016, the Virginia Department of Health recorded more than 10,600 chronic cases of hep C in the state, compared with just 6,675 two years prior. What’s more, the Centers for Disease Control and Prevention (CDC) currently considers eight counties in Virginia to be at a high risk for an HIV outbreak — further endangering injection drug users across the state.

In response, on July 1, the Department of Health will launch several syringe exchange programs to educate drug users about the risks of injecting and to distribute clean needles. Virginia recently passed a law legalizing syringe services programs and will be implementing the initiatives only in counties where the need is high, rather than making it a statewide program.