This vial contains 2 mg of fentanyl, which will kill a human. (Cliff Owen/AP)

Fatal drug overdoses increased 38 percent in Virginia between 2015 and 2016, an alarming jump that state health officials attribute to abuse of synthetic opioids, heroin and prescription fentanyl.

A new report from the state medical examiner found an even bigger increase — 175 percent — in deaths from several varieties of fentanyl, a pain medication significantly more potent than morphine.

At least 1,420 people died in Virginia last year of drug overdoses, the fourth year that drugs have outpaced motor vehicle accidents and gun-related incidents as the leading cause of unnatural death in the state. The state Health Department warned that the figure may be understating the reality, because the cause of death has not yet been certified for 60 cases from 2016.

The situation will probably get worse before it gets better, said State Health Commissioner Marissa Levine, who in November classified opioid addiction as an epidemic and declared a public health emergency .

“I don’t know when we’ll see a peak in deaths,” Levine said Thursday. “It’s not just heroin causing people to die. It’s fentanyl and synthetic fentanyl with different potencies. We’re now seeing carfentanil [a drug 100 times more potent than fentanyl, used to tranquilize elephants]. Someone who’s getting heroin laced with carfentanil could die easily.”

One of the most dramatic increases in the cause of overdose deaths came from a change in a drug. Before 2013, most fentanyl-related deaths were caused by illicit use of the prescription medication produced by pharmaceutical companies, the state report said.

But in the past several years, toxicology tests showed an increase in illicitly produced fentanyl and fentanyl “analogues” — drugs that resemble another and have a similar function but a different chemical structure.

But the most deadly combination in 2016 was a mixture of fentanyl and heroin. Kathrin “Rosie” Hobron, Virginia’s forensic epidemiologist, said dealers spiked heroin with cheaper fentanyl and fentanyl analogues, or in some cases sold heroin users fentanyl but described it as heroin. The combination of fentanyl mixed with heroin has been the biggest contributor to the spike in the number of fatal opioid over­doses in Virginia, state health officials said.

“That’s what’s really causing our problems now,” Hobron said. “A lot of drug users don’t know what they’re using.”

From 2007 to 2010, about 700 people died in Virginia each year from drug overdoses, mostly from prescription opioids. By 2011, heroin began turning up more often in toxicology reports, bringing the annual death toll from drug overdoses to about 800. Illicit fentanyl use and fentanyl analogues arrived in 2013 or so, Hobron said, and total drug overdose deaths rose to 1,028 by 2015.

Virginia is not alone in this crisis; in 2014, more than 28,000 people died of opioid overdoses across the country. Heroin deaths have tripled since 2010, with 10,500 deaths in 2014, according to the U.S. Department of Health and Human Services.

This crisis is not restricted to rural Virginia, where some who injured themselves doing heavy physical labor took prescription opioids for pain and became addicted. In urban areas of the state, fentanyl knockoffs and heroin are the major problem, both health officials said.

(Drug Enforcement Administration)

Levine, the state’s health commissioner, issued a standing prescription in November that allows any Virginia resident to get the drug Naloxone, which is used to treat overdoses, from a pharmacy.

This year, the Virginia General Assembly passed bills that legalize needle-exchange programs, because intravenous drug users are fueling a rise in hepatitis C and HIV infections; introduce initiatives to increase access to naloxone; change opioid prescription policies; and provide services to infants exposed to opioids in utero.

That’s a good start, but it’s going to take years of partnerships between law enforcement, the medical community and the public to address the underlying causes of the epidemic, Levine said.