Watch How the Drug Overdose Epidemic Spread in America

The epidemic of drug overdoses in the U.S. has reached crisis levels, according to newly published data from the County Health Rankings & Roadmaps project. The following map shows the spread in per-capita drug overdoses from 2002 to 2014, the most recent year for which data is available from the Centers for Disease Control and Prevention (CDC).

Because it’s difficult to determine the number of overdoses in small-population counties, the figures in this map represent the CDC’s statistical estimates for lethal overdoses in every county. In some cases, this undercounts fatalities, since the model tops out at “over 20 deaths per 100,000 people” when, in fact, a handful of outlying counties have figures much higher than this. But even though the estimates are flawed in some places, there’s enough hard data to show that regional epidemics, like that in the Appalachia region, for instance, began at an epicenter and spread rapidly to neighboring counties and states.

Most of the media coverage of this crisis has focused on spiking levels of heroin addiction, particularly in the Northeast. Several presidential hopefuls have also tackled the subject, and last month President Obama included over $1 billion in his budget proposal for combating heroin and opioid abuse.

A deeper dive into the figures, however, suggests that opioid abuse does not alone account for the dramatic increase in overdoses. While accidental deaths from recreational drug use are unquestionably on the rise, the topline figures encompass a wide variety of substances, from antidepressants and stimulants to street drugs to hormones and antibiotics.

CountyHealthRankings.org, which is a joint venture between the University of Wisconsin Population Health Institute and the Robert Wood Johnson Foundation, reports figures that include accidental overdoses as well as suicide through intentional drug poisoning and cases where the intent of the victim was unclear. Bridget Catlin, the co-director of the project, says this is the industry standard for measuring fatal overdoses.

Catherine O’Leary, managing director for the professional services firm KPMG, notes that not all drug overdoses fit the common image of junkies who went too far. “If a grandmother takes her prescribed heart medication incorrectly and dies, it gets lumped together with a drug overdose,” she says. Unfortunately, there is no obvious distinction in the way these deaths are reported, so it is not easy to tease out the difference between accidental misuse of legitimate prescriptions versus recreational use of drugs like heroin or cocaine that end tragically.

Of course, those ambiguities cannot fully account for the rise in drug-related deaths in the U.S. Figures that TIME pulled directly from the CDC for only the most unambiguous cases of unintended ODs from recreational drugs—”Accidental poisoning by and exposure to narcotics and psychodysleptics [hallucinogens],” which bears the code X42—reveal that the number of cases nationwide rose from 6,009 in 1999 to 16,822 in 2014, an increase of 140% after accounting for the growth in population size.

There are some simple ways to curb these deaths, Catlin says—including to make sure emergency personnel are trained in the administration of Naloxone, which can reverse the effects of an opioid overdose before the patient dies—but an epidemic with this many faces will require just as many solutions.